Carl Sagan Quotes

Carl Edward Sagan (November 9, 1934 – December 20, 1996) was an  American astronomer, cosmologist, astrophysicist, astrobiologist, author, science popularizer, and science communicator in astronomy and other natural sciences. He is best known as a science popularizer and communicator. His best known scientific contribution is research on extraterrestrial life, including experimental demonstration of the production of amino acids from basic chemicals by radiation. Sagan assembled the first physical messages sent into space: the Pioneer plaque and the Voyager Golden Record, universal messages that could potentially be understood by any extraterrestrial intelligence that might find them. Sagan argued the now accepted hypothesis that the high surface temperatures of Venus can be attributed to and calculated using the greenhouse effect.

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Carl Sagan Quotes

A book is made from a tree. It is an assemblage of flat, flexible parts (still called “leaves”) imprinted with dark pigmented squiggles. One glance at it and you hear the voice of another person, perhaps someone dead for thousands of years. Across the millennia, the author is speaking, clearly and silently, inside your head, directly to you. Writing is perhaps the greatest of human inventions, binding together people, citizens of distant epochs, who never knew one another. Books break the shackles of time ― proof that humans can work magic. – Carl Sagan

A book is proof that humans are capable of working magic. – Carl Sagan

A central lesson of science is that to understand complex issues (or even simple ones), we must try to free our minds of dogma and to guarantee the freedom to publish, to contradict, and to experiment. Arguments from authority are unacceptable. – Carl Sagan

A galaxy is composed of gas and dust and stars – billions upon billions of stars. Every star may be a sun to someone. – Carl Sagan

A googleplex is precisely as far from infinity as is the number 1 … No matter what number you have in mind, infinity is larger. – Carl Sagan

A millennium before Europeans were willing to divest themselves of the Biblical idea that the world was a few thousand years old, the Mayans were thinking of millions and the Hindus billions. – Carl Sagan

A multitude of aspects of the natural world that were considered miraculous only a few generations ago are now thoroughly understood in terms of physics and chemistry. – Carl Sagan

A proclivity for science is embedded deeply within us, in all times, places, and cultures. It has been the means for our survival. It is our birthright. When, through indifference, inattention, incompetence, or fear of skepticism, we discourage children from science, we are disenfranchising them, taking from them the tools needed to manage their future. – Carl Sagan

A stars rich in europium; of distant galaxies analyzed through the collective light of a hundred billion constituent stars. Astronomical spectroscopy is an almost magical technique. It amazes me still. Auguste Comte picked a particularly unfortunate example. – Carl Sagan

A still more glorious dawn awaits / not a sunrise, but a galaxy-rise / a morning filled with 400 billion suns / the rising of the milky way – Carl Sagan

Absence of evidence is not evidence of absence. – Carl Sagan

Absolute certainty will always elude us. We will always be mired in error. The most each generation can hope for is to reduce the error. . . . – Carl Sagan

Across the sea of space, the stars are other suns. – Carl Sagan

Advances in medicine and agriculture have saved vastly more lives than have been lost in all the wars in history. – Carl Sagan

After I give lectures-on almost any subject-I am often asked, “Do you believe in UFOs?” I’m always struck by how the question is phrased, the suggestion that this is a matter of belief and not evidence. I’m almost never asked, “How good is the evidence that UFOs are alien spaceships?” – Carl Sagan

All colours are arbitrary. – Carl Sagan

All inquires carry with them some element of risk. There is no guarantee that the universe will conform to our predispositions. – Carl Sagan

All inquiries carry with them some element of risk. – Carl Sagan

All of the books in the world contain no more information than is broadcast as video in a single large American city in a single year. Not all bits have equal value. – Carl Sagan

All of the rocky and metallic material we stand on, the iron in our blood, the calcium in our teeth, the carbon in our genes were produced billions of years ago in the interior of a red giant star. We are made of star stuff. – Carl Sagan

All over the world there are enormous numbers of smart, even gifted, people who harbor a passion for science. But that passion is unrequited. Surveys suggest that some 95% of Americans are “scientifically illiterate.” That’s…the same fraction…of slaves who were illiterate before the Civil War… – Carl Sagan

An extraterrestrial being, newly arrived on Earth – scrutinizing what we mainly present to our children in television, radio, movies, newspapers, magazines, the comics, and many books – might easily conclude that we are intent on teaching them murder, rape, cruelty, superstition, credulity, and consumerism. We keep at it, and through constant repetition many of them finally get it. – Carl Sagan

An extraterrestrial being, newly arrived on Earth – scrutinizing what we mainly present to our children in television, radio, movies, newspapers, magazines, the comics, and many books – might easily conclude that we are intent on teaching them murder, rape, cruelty, superstition, credulity and consumerism. – Carl Sagan

An organism at war with itself is doomed. – Carl Sagan

And after we returned to the savannahs and abandoned the trees, did we long for those great graceful leaps and ecstatic moments of weightlessness in the shafts of sunlight of the forest roof? – Carl Sagan

And you are made of a hundred trillion cells. We are, each of us, a multitude. – Carl Sagan

Any civilization that doesn’t develop space travel dies. – Carl Sagan

Any sufficiently crisp question can be answered by a single binary digit-0 or 1, yes or no. – Carl Sagan

Anything else you’re interested in is not going to happen if you can’t breathe the air and drink the water. Don’t sit this one out. Do something. You are by accident of fate alive at an absolutely critical moment in the history of our planet. – Carl Sagan

Arguments from authority carry little weight – authorities have made mistakes in the past. They will do so again in the future. Perhaps a better way to say it is that in science there are no authorities; at most, there are experts. – Carl Sagan

As agonizing a disease as cancer is, I do not think it can be said that our civilization is threatened by it. … But a very plausible case can be made that our civilization is fundamentally threatened by the lack of adequate fertility control. Exponential increases of population will dominate any arithmetic increases, even those brought about by heroic technological initiatives, in the availability of food and resources, as Malthus long ago realized. – Carl Sagan

As the ancient myth makers knew, we are children equally of the earth and the sky – Carl Sagan

Ask courageous questions. Do not be satisfied with superficial answers. Be open to wonder and at the same time subject all claims to knowledge, without exception, to intense skeptical scrutiny. Be aware of human fallibility. Cherish your species and your planet. – Carl Sagan

Ask courageous questions. Do not be satisfied with superficial answers. – Carl Sagan

At a few hundred kilometers altitude, the Earth fills half your sky, and the band of blue that stretches from Mindanao to Bombay, which your eye encompasses in a single glance, can break your heart with its beauty. Home you think. Home. This is my world. This is where I come from. Everyone I know, everyone I ever heard of, grew up down there, under that relentless and exquisite blue. – Carl Sagan

At the heart of science is an essential balance between two seemingly contradictory attitudes—an openness to new ideas, no matter how bizarre or counterintuitive they may be, and the most ruthless skeptical scrutiny of all ideas, old and new. This is how deep truths are winnowed from deep nonsense. – Carl Sagan

Atoms are mainly empty space. Matter is composed chiefly of nothing. – Carl Sagan

Avoidable human misery is more often caused not so much by stupidity as by ignorance, particularly our ignorance about ourselves. – Carl Sagan

Be grateful everyday for the brief but magnificent opportunity that life provides. – Carl Sagan

Because men, compared to male chimps, have such relatively small testicles (large testicles indicate a species where many males mate, one after the other, with the same female), we might guess that promiscuous societies were uncommon in the immediate human past. – Carl Sagan

Before we invented civilization our ancestors lived mainly in the open out under the sky. Before we devised artificial lights and atmospheric pollution and modern forms of nocturnal entertainment we watched the stars. There were practical calendar reasons of course but there was more to it than that. Even today the most jaded city dweller can be unexpectedly moved upon encountering a clear night sky studded with thousands of twinkling stars. When it happens to me after all these years it still takes my breath away. – Carl Sagan

Better by far to embrace the hard truth than a reassuring fable. If we crave some cosmic purpose, then let us find ourselves a worthy goal. – Carl Sagan

Better the hard truth, I say, than the comforting fantasy. – Carl Sagan

Better the hard truth, I say, than the comforting fantasy. And in the final tolling it often turns out that the facts are more comforting than the fantasy. – Carl Sagan

Billions and billions. – Carl Sagan

Books are key to understanding the world and participating in a democratic society. – Carl Sagan

Books are like seeds. They can lie dormant for centuries and then flower in the most unpromising soil. – Carl Sagan

Books break the shackles of time, proof that humans can work magic. – Carl Sagan

Books permit us to voyage through time, to tap the wisdom of our ancestors. – Carl Sagan

Books tap the wisdom of our species — the greatest minds, the best teachers — from all over the world and from all our history. And they’re patient. – Carl Sagan

Both the Freudian and the Platonic metaphors emphasize the considerable independence of and tension among the constituent parts of the psyche, a point that characterizes the human condition. – Carl Sagan

But amid much elegance and precision, the details of life and the Universe also exhibit haphazard, jury-rigged arrangements and much poor planning. What shall we make of this: an edifice abandoned early in construction by the architect? – Carl Sagan

But down deep, at the molecular heart of life we’re essentially identical to trees. – Carl Sagan

But I could be wrong. – Carl Sagan

But I try not to think with my gut. If I’m serious about understanding the world, thinking with anything besides my brain, as tempting as that might be, is likely to get me into trouble. – Carl Sagan

But nature is always more subtle, more intricate, more elegant than what we are able to imagine. – Carl Sagan

But our preferences do not determine what’s true. – Carl Sagan

But the fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown. – Carl Sagan

But, Jefferson worried that the people – and the argument goes back to Thucydides and Aristotle – are easily misled. He also stressed, passionately and repeatedly, that it was essential for the people to understand the risks and benefits of government, to educate themselves, and to involve themselves in the political process. Without that, he said, the wolves will take over. – Carl Sagan

By looking far out into space we are also looking far back into time, back toward the horizon of the universe, back toward the epoch of the Big Bang. – Carl Sagan

Centuries hence, when current social and political problems may seem as remote as the problems of the Thirty Years’ War are to us, our age may be remembered chiefly for one fact: It was the time when the inhabitants of the earth first made contact with the vast cosmos in which their small planet is embedded. – Carl Sagan

Children [are] born with a zest for knowledge, aware that they must live in a future molded by science, but so often convinced by their culture that science is not for them. – Carl Sagan

Chlorine is a deadly poison gas employed on European battlefields in World War I. Sodium is a corrosive metal which burns upon contact with water. Together they make a placid and unpoisonous material, table salt. Why each of these substances has the properties it does is a subject called chemistry. – Carl Sagan

Cleverly designed experiments are the key. – Carl Sagan

Clutching our crystals and religiously consulting our horoscopes, our critical faculties in steep decline, unable to distinguish between what’s true and what feels good, we slide, almost without noticing, into superstition and darkness. – Carl Sagan

Comets giveth and comets taketh away. – Carl Sagan

Cosmos is a Greek word for the order of the universe. It is, in a way, the opposite of Chaos. It implies the deep interconnectedness of all things. It conveys awe for the intricate and subtle way in which the universe is put together. – Carl Sagan

Curiosity and the urge to solve problems are the emotional hallmarks of our species … – Carl Sagan

Cutting off fundamental, curiosity-driven science is like eating the seed corn. We may have a little more to eat next winter but what will we plant so we and our children will have enough to get through the winters to come? – Carl Sagan

Demon mean knowledge in Greek, especially about the material world. Science means knowledge in Latin. A jurisdictional dispute is exposed, even if we look no further – Carl Sagan

Discussing the possibilities of extraterrestrial life: I would love it even if they were short, sullen, grumpy and sexually obsessed. But there just isn’t any good evidence. – Carl Sagan

Don’t judge everyone else by your own limited experience. – Carl Sagan

Each of us is a tiny being, permitted to ride on the outermost skin of one of the smaller planets for a few dozen trips around the local star. – Carl Sagan

Eratosthenes’s only tools were sticks, eyes, feet, and brains; plus a zest for experiment. With those tools he correctly deduced the circumference of the Earth, to high precision, with an error of only a few percent. That’s pretty good figuring for 2200 years ago. – Carl Sagan

Even Johannes Kepler, Isaac Newton, Charles Darwin, Gregor Mendel, and Albert Einstein made serious mistakes. But the scientific enterprise arranges things so that teamwork prevails: What one of us, even the most brilliant among us, misses, another of us, even someone much less celebrated and capable, may detect and rectify. – Carl Sagan

Even these stars, which seem so numerous, are as sand, as dust – or less than dust – in the enormity of the space in which there is nothing. – Carl Sagan

Even through your hardest days, remember we are all made of stardust. – Carl Sagan

Even today the most jaded city dweller can be unexpectedly moved upon encountering a clear night sky studded with thousands of twinkling stars. When it happens to me after all these years it still takes my breath away. – Carl Sagan

Every aspect of Nature reveals a deep mystery and touches our sense of wonder and awe. Those afraid of the universe as it really is, those who pretend to nonexistent knowledge and envision a Cosmos centered on human beings will prefer the fleeting comforts of superstition. They avoid rather than confront the world. But those with the courage to explore the weave and structure of the Cosmos, even where it differs profoundly from their wishes and prejudices, will penetrate its deepest mysteries.

Every cell is a triumph of natural selection, and we’re made of trillions of cells. Within us, is a little universe. – Carl Sagan

Every kid starts out as a natural-born scientist, and then we beat it out of them. A few trickle through the system with their wonder and enthusiasm for science intact. – Carl Sagan

Every one of us is, in the cosmic perspective, precious. If a human disagrees with you, let him live. In a hundred billion galaxies, you will not find another. – Carl Sagan

Every star may be a sun to someone. – Carl Sagan

Every thinking person fears nuclear war, and every technological state plans for it. Everyone knows it is madness, and every nation has an excuse – Carl Sagan

Every time you look up at the sky, every one of those points of light is a reminder that fusion power is extractable from hydrogen and other light elements, and it is an everyday reality throughout the Milky Way Galaxy. – Carl Sagan

Except for children (who don’t know enough not to ask the important questions), few of us spend time wondering why nature is the way it is . . . – Carl Sagan

Except for fools and madmen, everyone knows that nuclear war would he an unprecedented human catastrophe. – Carl Sagan

Except in pure mathematics, nothing is known for certain (although much is certainly false). – Carl Sagan

Exploration is in our nature. We began as wanderers, and we are wanderers still. We have lingered long enough on the shores of the cosmic ocean. We are ready at last to set sail for the stars. – Carl Sagan

Extinction is the rule. Survival is the exception. – Carl Sagan

Extraordinary claim requires extraordinary proof. – Carl Sagan

Extraordinary claims require extraordinary evidence. – Carl Sagan

Extraordinary observations require extraordinary evidence to make them believable. – Carl Sagan

Fanatical ethnic or religious or national chauvinisms are a little difficult to maintain when we see our planet as a fragile blue crescent fading to become an inconspicuous point of light against a bastion and citadel of the stars. – Carl Sagan

Few scientists now dispute that today’s soaring levels of carbon dioxide and other gases in the atmosphere will cause global temperature averages to rise by as much as nine degrees Fahrenheit sometime after the year 2000. – Carl Sagan

Finding out the way the world really works requires a mix of hunches, intuition and brilliant creativity; it also requires skeptical scrutiny of every step. – Carl Sagan

Finding the occasional straw of truth awash in a great ocean of confusion and bamboozle requires intelligence, vigilance, dedication and courage. But if we don’t practice these tough habits of thought, we cannot hope to solve the truly serious problems that face us – and we risk becoming a nation of suckers, up for grabs by the next charlatan who comes along. – Carl Sagan

First rule in government spending: Why build one, when you can have two at twice the price? – Carl Sagan

Football is a thinly disguised re-enactment of hunting; we played it before we were human. – Carl Sagan

For a long time the human instinct to understand was thwarted by facile religious explanations. – Carl Sagan

For all I know we may be visited by a different extraterrestrial civilization every second Tuesday, but there’s no support for this appealing idea. The extraordinary claims are not supported by extraordinary evidence. – Carl Sagan

For all its material advantages, the sedentary life has left us edgy, unfulfilled, even after 400 generations in villages and cities, we haven’t forgotten: The open road still softly calls like a nearly forgotten song of childhood. – Carl Sagan

For all our conceits about being the center of the universe, we live in a routine planet of a humdrum star stuck away in an obscure corner … on an unexceptional galaxy which is one of about 100 billion galaxies. … That is the fundamental fact of the universe we inhabit, and it is very good for us to understand that. – Carl Sagan

For all our failings, despite our limitations and fallibilities, we humans are capable of greatness. – Carl Sagan

For me, it is far better to grasp the Universe as it really is than to persist in delusion, however satisfying and reassuring. – Carl Sagan

For myself, I like a universe that, includes much that is unknown and, at the same time, much that is knowable. A universe in which everything is known would be static and dull, as boring as the heaven of some weak-minded theologians. A universe that is unknowable is no fit place for a thinking being. The ideal universe for us is one very much like the universe we inhabit. And I would guess that this is not really much of a coincidence. – Carl Sagan

For years I’ve been stressing with regard to UFOs that extraordinary claims require extraordinary evidence. – Carl Sagan

Frederick Douglass taught that literacy is the path from slavery to freedom. There are many kinds of slavery and many kinds of freedom, but reading is still the path. – Carl Sagan

Frequently seen attributed to Sagan, but always without any citation. Webmaster has found no proof that Sagan ever said, wrote or originated this. Also seen as, Science is a way of trying not to fool yourself.” Contact webmaster if you know a primary verbatim source for either of these attributed quotes. Likely a paraphrase from a known quote by Richard Feynman, that begins, The first principle is that you must not fool yourself…”, on the Richard Feynman Quotes page of this website. – Carl Sagan

Goddard represented a unique combination of visionary dedication and technological brilliance. He studied physics because he needed physics to get to Mars. In reading the notebooks of Robert Goddard, I am struck by how powerful his exploratory and scientific motivations were – and how influental speculative ideas, even erroneous ones, can be on the shaping of the future. – Carl Sagan

He didn’t want to believe. He wanted to know. – Carl Sagan

He sought a way to preserve the past. John Hershel was one of the founders of a new form of time travel…. a means to capture light and memories. He actually coined a word for it… photography. When you think about it, photography is a form of time travel. This man is staring at us from across the centuries, a ghost preserved by light. – Carl Sagan

History is full of people who out of fear, or ignorance, or lust for power has destroyed knowledge of immeasurable value which truly belongs to us all. We must not let it happen again. – Carl Sagan

How lucky we are to live in this time / the first moment in human history / when we are in fact visiting other worlds – Carl Sagan

How smart does a chimp have to be before killing him constitutes murder? – Carl Sagan

I also wish that the Pledge of Allegiance were directed at the Constitution and the Bill of Rights, as it is when the President takes his oath of office, rather than to the flag and the nation – Carl Sagan

I am not an atheist. An atheist is someone who has compelling evidence that there is no Judeo-Christian-Islamic God. I am not that wise, but neither do I consider there to be anything approaching adequate evidence for such a god. Why are you in such a hurry to make up your mind? Why not simply wait until there is compelling evidence? – Carl Sagan

I am tormented with an everlasting itch for things remote. I love to sail forbidden seas … – Carl Sagan

I believe our future depends powerfully on how well we understand this cosmos in which we float, like a mote of dust in the morning sky. – Carl Sagan

I believe that in every person is a kind of circuit which resonates to intellectual discovery—and the idea is to make that resonance work – Carl Sagan

I believe that the extraordinary should be pursued. But extraordinary claims require extraordinary evidence. – Carl Sagan

I believe that the extraordinary should certainly be pursued. But extraordinary claims require extraordinary evidence. – Carl Sagan

I can find in my undergraduate classes, bright students who do not know that the stars rise and set at night, or even that the Sun is a star. – Carl Sagan

I consider it an extremely dangerous doctrine, because the more likely we are to assume that the solution comes from the outside, the less likely we are to solve our problems ourselves. – Carl Sagan

I don’t feel rejected by the sky. I’m a part of it- tiny, to be sure, but everything is tiny compared to that overwhelming immensity. – Carl Sagan

I don’t know the answer. Maybe no one knows. Maybe when you grow up, you’ll be the first to find out. – Carl Sagan

I don’t know why you’re on Mars. Maybe you’re there because we recognize we have to carefully move small asteroids around to avert the possibility of one impacting the Earth with catastrophic consequences, and while we’re up in near-Earth space, it’s only a hop, skip, and a jump to Mars. Or maybe we’re on Mars because we recognize that if there are human communities on many different worlds, the chances of us being rendered extinct by some catastrophe on one world is much less. Or maybe we’re on Mars because of the magnificent science that can be done there, that the gates of the wonder world are opening in our time. Or maybe we’re on Mars because we have to be, because there’s a deep nomadic impulse built into us by the evolutionary process. We come, after all, from hunter-gatherers, and for 99.9% of our tenure on Earth we’ve been wanderers. And, the next place to wander to is Mars. But whatever the reason you’re on Mars is, I’m glad you’re there. And I wish I was with you. – Carl Sagan

I grew up in Brooklyn, New York … a city neighborhood that included houses, lampposts, walls, and bushes. But with an early bedtime in the winter, I could look out my window and see the stars, and the stars were not like anything else in my neighborhood. [At age 5] I didn’t know what they were.
[At age 9] my mother … said to me, “You have a library card now, and you know how to read. Take the streetcar to the library and get a book on stars.” … I stepped up to the big librarian and asked for a book on stars. … I sat down and found out the answer, which was something really stunning.
I found out that the stars are glowing balls of gas. I also found out that the Sun is a star but really close and that the stars are all suns except really far away I didn’t know any physics or mathematics at that time, but I could imagine how far you’d have to move the Sun away from us till it was only as bright as a star. It was in that library, reading that book, that the scale of the universe opened up to me. There was something beautiful about it.
At that young age, I already knew that I’d be very happy if I could devote my life to finding out more about the stars and the planets that go around them. And it’s been my great good fortune to do just that. – Carl Sagan

I have a foreboding of an America in my children’s or grandchildren’s time … when awesome technological powers are in the hands of a very few, and no one representing the public interest can even grasp the issues; when the people have lost the ability to set their own agendas or knowledgeably question those in authority; when clutching our crystals and nervously consulting our horoscopes, our critical faculties in decline, unable to distinguish between what feels good and what’s true, we slide, almost without noticing, back into superstitions and darkness. – Carl Sagan

I never said it. Honest. Oh, I said there are maybe 100 billion galaxies and 10 billion trillion stars. It’s hard to talk about the Cosmos without using big numbers. I said “billion” many times on the Cosmos television series, which was seen by a great many people. But I never said “billions and billions.” For one thing, it’s too imprecise. How many billions are “billions and billions”? A few billion? Twenty billion. A hundred billion? “Billions and billions” is pretty vague. When we reconfigured and updated the series, I checked-and sure enough, I never said it. – Carl Sagan

I promise to question everything my leaders tell me. I promise to use my critical faculties. I promise to develop my independence of thought. I promise to educate myself so I can make my own judgments. – Carl Sagan

I set before you two ways: You can use your technology to destroy yourselves or to carry you to the planets and the stars. It’s up to you. – Carl Sagan

I think if we ever reach the point where we think we thoroughly understand who we are and where we came from, we will have failed. – Carl Sagan

I think the discomfort that some people feel in going to the monkey cages at the zoo is a warning sign. – Carl Sagan

I think the health of our civilization, the depth of our awareness about the underpinnings of our culture, and our concern for the future, can all be tested by how well we support our libraries. – Carl Sagan

I wanted to be a scientist from my earliest school days. The crystallizing moment came when I first caught on that stars are mighty suns, and how staggeringly far away they must be to appear to us as mere points of light. I’m not sure I even knew the word science then, but I was gripped by the prospect of understanding how things work, of helping to uncover deep mysteries, of exploring new worlds. – Carl Sagan

I went to the librarian and asked for a book about stars…. And the answer was stunning. It was that the Sun was a star but really close. The stars were suns, but so far away they were just little points of light…. The scale of the universe suddenly opened up to me. It was a kind of religious experience. There was a magnificence to it, a grandeur, a scale which has never left me. Never ever left me. – Carl Sagan

I would be very ashamed of my civilization if we did not try to find out if there is life in outer space. – Carl Sagan

I would love to believe that when I die I will live again, that some thinking, feeling, remembering part of me will continue. But as much as I want to believe that, and despite the ancient and worldwide cultural traditions that assert an afterlife, I know of nothing to suggest that it is more than wishful thinking. – Carl Sagan

I would rather be a transformed ape than a degenerate son of Adam. – Carl Sagan

I’d like the [Cosmos] series to be so visually stimulating that somebody who isn’t even interested in the concepts will just watch for the effects. And I’d like people who are prepared to do some thinking to be really stimulated. – Carl Sagan

I’m struck again by the irony that spaceflight-conceived in the cauldron of nationalist rivalries and hatreds-brings with it a stunning transnational vision. You spend even a little time contemplating the Earth from orbit and the most deeply engrained nationalisms begin to erode. They seem the squabbles of mites on a plum. – Carl Sagan

I’d like the [Cosmos] series to be so visually stimulating that somebody who isn’t even interested in the concepts will just watch for the effects. And I’d like people who are prepared to do some thinking to be really stimulated. – Carl Sagan

If all the suns but ours collapsed tonight, how many lifetimes would it take us to realize that we were alone? – Carl Sagan

If chimpanzees have consciousness, if they are capable of abstractions, do they not have what until now has been described as ‘human rights’? How smart does a chimp have to be before killing him constitutes murder? – Carl Sagan

If constellations had been named in the 20th century, I suppose we would see bicycles. – Carl Sagan

If God is omnipotent and omniscient, why didn’t he start the universe out in the first place so it would come out the way he wants? Why’s he constantly repairing and complaining? No, there’s one thing the Bible makes clear: The biblical God is a sloppy manufacturer. He’s not good at design, he’s not good at execution. He’d be out of business, if there was any competition. – Carl Sagan

If I finish a book a week, I will read only a few thousand books in my lifetime, about a tenth of a percent of the contents of the greatest libraries of our time. The trick is to know which books to read. – Carl Sagan

If intelligence is our only edge, we must learn to use it better, to shape it, to understand its limitations and deficiencies — to use it as cats use stealth, as katydids use camouflage — to make it the tool of our survival. – Carl Sagan

If it can be destroyed by the truth, it deserves to be destroyed by the truth. – Carl Sagan

If our long-term survival is at stake, we have a basic responsibility to our species to venture to other worlds. Sailors on a becalmed sea, we sense the stirring of a breeze. – Carl Sagan

If the greenhouse effect is a blanket in which we wrap ourselves to keep warm, nuclear winter kicks the blanket off. – Carl Sagan

If the press descended, the science would surely suffer. – Carl Sagan

If the world is to be understood, if we are to avoid such logical paradoxes when traveling at high speeds, there are some rules, commandments of Nature, that must be obeyed. Einstein codified these rules in the special theory of relativity. Light (reflected or emitted) from an object travels at the same velocity whether the object is moving or stationary: Thou shalt not add thy speed to the speed of light. Also, no material object may move faster than light: Thou shalt not travel at or beyond the speed of light. Nothing in physics prevents you from traveling as close to the speed of light as you like; 99.9 percent of the speed of light would be just fine. But no matter how hard you try, you can never gain that last decimal point. For the world to be logically consistent there must be a cosmic speed limit. Otherwise, you could get to any speed you wanted by adding velocities on a moving platform. – Carl Sagan

If there is life, then I believe we should do nothing to disturb that life. Mars then, belongs to the Martians, even if they are microbes. – Carl Sagan

If we are merely matter intricately assembled, is this really demeaning? If there’s nothing here but atoms, does that make us less or does that make matter more? – Carl Sagan

If we are not able to ask skeptical questions, to interrogate those who tell us that something is true, to be skeptical of those in authority, then, we are up for grabs for the next charlatan (political or religious) who comes rambling along. – Carl Sagan

If we can’t think for ourselves, if we’re unwilling to question authority, then we’re just putty in the hands of those in power. But if the citizens are educated and form their own opinions, then those in power work for us. In every country, we should be teaching our children the scientific method and the reasons for a Bill of Rights. With it comes a certain decency, humility and community spirit. In the demon-haunted world that we inhabit by virtue of being human, this may be all that stands between us and the enveloping darkness. – Carl Sagan

If we continue to accumulate only power and not wisdom, we will surely destroy ourselves. – Carl Sagan

If we could travel into the past, it’s mind-boggling what would be possible. For one thing, history would become an experimental science, which it certainly isn’t today. The possible insights into our own past and nature and origins would be dazzling. For another, we would be facing the deep paradoxes of interfering with the scheme of causality that has led to our own time and ourselves. I have no idea whether it’s possible, but it’s certainly worth exploring. – Carl Sagan

If we do not speak for Earth, who will? If we are not committed to our own survival, who will be? – Carl Sagan

If we like them, they’re freedom fighters . . . If we don’t like them, they’re terrorists. In the unlikely case we can’t make up our minds, they’re temporarily only guerrillas. – Carl Sagan

If we lived on a planet where nothing ever changed, there would be little to do. There would be nothing to figure out. There would be no impetus for science. And if we lived in an unpredictable world, where things changed in random or very complex ways, we would not be able to figure things out. But we live in an in-between universe, where things change, but according to patterns, rules, or as we call them, laws of nature. If I throw a stick up in the air, it always falls down. If the sun sets in the west, it always rises again the next morning in the east. And so it becomes possible to figure things out. We can do science, and with it we can improve our lives. – Carl Sagan

If we long for our planet to be important, there is something we can do about it. We make our world significant by the courage of our questions and by the depth of our answers. – Carl Sagan

If we long to believe that the stars rise and set for us, that we are the reason there is a Universe, does science do us a disservice in deflating our conceits? – Carl Sagan

If we offer too much silent assent about mysticism and superstition – even when it seems to be doing a little good – we abet a general climate in which scepticism is considered impolite, science tiresome, and rigorous thinking somehow stuffy and inappropriate. – Carl Sagan

If we say that God has always been, why not save a step and conclude that the universe has always been? – Carl Sagan

If we teach only the findings and products of science – no matter how useful and even inspiring they may be – without communicating its critical method, how can the average person possibly distinguish science from pseudoscience? – Carl Sagan

If we’re capable of conjuring up terrifying monsters in childhood, why shouldn’t some of us, at least on occasion, be able to fantasize something similar, something truly horrifying, a shared delusion, as adults? – Carl Sagan

If you are only skeptical, then no new ideas make it through to you. You become a crotchety old person convinced that nonsense is ruling the world. (There is, of course, much data to support you.) But every now and then, a new idea turns out to be on the mark, valid and wonderful. If you are too much in the habit of being skeptical about everything, you are going to miss or resent it, and either way you will be standing in the way of understanding and progress. – Carl Sagan

If you are only skeptical, then no new ideas make it through to you. – Carl Sagan

If you want to make a [rhubarb] pie from scratch, first you have to create the universe. – Carl Sagan

If you want to make an apple pie from scratch, you must first create the universe. – Carl Sagan

If you want to save your child from polio, you can pray or you can inoculate….Try science. – Carl Sagan

If you want to save your child from polio, you can pray or you can inoculate. … Choose science. – Carl Sagan

If you wish to make an apple pie from scratch, you must first invent the universe. – Carl Sagan

I’m only a four-dimensional creature. Haven’t got a clue how to visualise infinity. Even Einstein hadn’t. I know because I asked him – Carl Sagan

Imagination will often carry us to worlds that never were, but without it we go nowhere. – Carl Sagan

Imagine a room awash in gasoline, and there are two implacable enemies in that room. One of them has nine thousand matches. The other has seven thousand matches. Each of them is concerned about who’s ahead, who’s stronger. Well that’s the kind of situation we are actually in. The amount of weapons that are available to the United States and the Soviet Union are so bloated, so grossly in excess of what’s needed to dissuade the other, that if it weren’t so tragic, it would be laughable. What is necessary is to reduce the matches and to clean up the gasoline. – Carl Sagan

Imagine that I am riding a bicycle toward you. As I approach an intersection I nearly collide, so it seems to me, with a horse drawn cart. I swerve and barely avoid being run over. Now think of the event again, and imagine that the cart and the bicycle are both traveling close to the speed of light. If you are standing down the road, the cart is traveling at right angles to your light of sight. You see me, by reflected sunlight, traveling toward you. Would not my speed be added to the speed of light so that my image would get to you considerably before the image of the cart? Should you not see me swerve before you see the cart arrive? Can the cart and I approach the intersection simultaneously from my point of view, but not from yours? Could I experience a near collision with the cart while you perhaps see me swerve around nothing and pedal cheerfully on toward the town of Vinci? These are curious and subtle questions. They challenge the obvious. There is a reason that no one thought of them before Einstein. From such elementary questions, Einstein produced a fundamental rethinking of the world, a revolution in physics. – Carl Sagan

Imagine we could accelerate continuously at 1 g — what we’re comfortable with on good old terra firma — to the midpoint of our voyage, and decelerate continuously at 1 g until we arrive at our destination. It would take a day to get to Mars, a week and a half to Pluto, a year to the Oort Cloud, and a few years to the nearest stars. – Carl Sagan

Imagine you want to know the sex of your unborn child. There are several approaches. You could, for example, do what the late film star … Cary Grant did before he was an actor: In a carnival or fair or consulting room, you suspend a watch or a plumb bob above the abdomen of the expectant mother; if it swings left-right it’s a boy, and if it swings forward-back it’s a girl. The method works one time in two. Of course he was out of there before the baby was born, so he never heard from customers who complained he got it wrong. … But if you really want to know, then you go to amniocentesis, or to sonograms; and there your chance of being right is 99 out of 100. … If you really want to know, you go to science. – Carl Sagan

In a complex universe, in a society undergoing unprecedented change, how can we find the truth if we are not willing to question everything and to give a fair hearing to everything? – Carl Sagan

In a lot of scientists, the ratio of wonder to skepticism declines in time. That may be connected with the fact that in some fields—mathematics, physics, some others—the great discoveries are almost entirely made by youngsters. – Carl Sagan

In all our searching, the only thing we’ve found that makes the emptiness bearable is each other. – Carl Sagan

In college, in the early 1950s, I began to learn a little about how science works, the secrets of its great success, how rigorous the standards of evidence must be if we are really to know something is true, how many false starts and dead ends have plagued human thinking, how our biases can colour our interpretation of evidence, and how often belief systems widely held and supported by the political, religious and academic hierarchies turn out to be not just slightly in error, but grotesquely wrong. – Carl Sagan

In exchange for freedom of inquiry, scientists are obliged to explain their work. – Carl Sagan

‘In his celebrated book, ‘On Liberty’, the English philosopher John Stuart Mill argued that silencing an opinion is “a peculiar evil.” If the opinion is right, we are robbed of the “opportunity of exchanging error for truth”; and if it’s wrong, we are deprived of a deeper understanding of the truth in its “collision with error.” If we know only our own side of the argument, we hardly know even that: it becomes stale, soon learned by rote, untested, a pallid and lifeless truth.’ – Carl Sagan

In Italy, the Inquisition was condemning people to death until the end of the eighteenth century, and inquisitional torture was not abolished in the Catholic Church until 1816. The last bastion of support for the reality of witchcraft and the necessity of punishment has been the Christian churches. – Carl Sagan

In many cultures it is customary to answer that God created the universe out of nothing. But this is mere temporizing. If we wish courageously to pursue the question, we must, of course ask next where God comes from? And if we decide this to be unanswerable, why not save a step and conclude that the universe has always existed? – Carl Sagan

In more than one respect, the exploring of the Solar System and homesteading other worlds constitutes the beginning, much more than the end, of history. – Carl Sagan

In Mozambique, the story goes, monkeys do not talk, because they know if they utter even a single word some man will come and put them to work. – Carl Sagan

In order to make an apple pie from scratch, you must first invent the universe. – Carl Sagan

In our obscurity – in all this vastness – there is no hint that help will come from elsewhere to save us from ourselves. It is up to us. – Carl Sagan

In our time, we have sifted the sands of Mars, we have established a presence there, we have fulfilled a century of dreams! – Carl Sagan

In science it often happens that scientists say, ‘You know that’s a really good argument; my position is mistaken,’ and then they would actually change their minds and you never hear that old view from them again. They really do it. – Carl Sagan

In the 1920s, there was a dinner at which the physicist Robert W. Wood was asked to respond to a toast … To physics and metaphysics.” Now by metaphysics was meant something like philosophy—truths that you could get to just by thinking about them. Wood took a second, glanced about him, and answered along these lines: The physicist has an idea, he said. The more he thinks it through, the more sense it makes to him. He goes to the scientific literature, and the more he reads, the more promising the idea seems. Thus prepared, he devises an experiment to test the idea. The experiment is painstaking. Many possibilities are eliminated or taken into account; the accuracy of the measurement is refined. At the end of all this work, the experiment is completed and … the idea is shown to be worthless. The physicist then discards the idea, frees his mind (as I was saying a moment ago) from the clutter of error, and moves on to something else. The difference between physics and metaphysics, Wood concluded, is that the metaphysicist has no laboratory. – Carl Sagan

In the deepest sense the search for extraterrestrial intelligence is a search for ourselves. – Carl Sagan

In the fabric of space and in the nature of matter, as in a great work of art, there is, written small, the artist’s signature. – Carl Sagan

In the long run, the aggressive civilizations destroy themselves, almost always. It’s their nature . They can’t help it. – Carl Sagan

In the middle 1970s an astronomer I admire put together a modest manifesto called “Objections to Astrology” and asked me to endorse it. I struggled with his wording, and in the end found myself unable to sign, not because I thought astrology has any validity whatever, but because I felt (and still feel) that the tone of the statement was authoritarian. – Carl Sagan

In the vastness of the Cosmos there must be other civilizations far older and more advanced than ours. – Carl Sagan

In the way that scepticism is sometimes applied to issues of public concern, there is a tendency to belittle, to condescend, to ignore the fact that, deluded or not, supporters of superstition and pseudoscience are human beings with real feelings, who, like the sceptics, are trying to figure out how the world works and what our role in it might be. Their motives are in many cases consonant with science. If their culture has not given them all the tools they need to pursue this great quest, let us temper our criticism with kindness. None of us comes fully equipped. – Carl Sagan

Intellectual capacity is no guarantee against being dead wrong. – Carl Sagan

Is it fair to be suspicious of an entire profession because of a few bad apples? There are at least two important differences, it seems to me. First, no one doubts that science actually works, whatever mistaken and fraudulent claim may from time to time be offered. But whether there are any miraculous cures from faith-healing, beyond the body’s own ability to cure itself, is very much at issue. Secondly, the expose’ of fraud and error in science is made almost exclusively by science. But the exposure of fraud and error in faith-healing is almost never done by other faith-healers. – Carl Sagan

Is mankind alone in the universe? Or are there somewhere other intelligent beings looking up into their night sky from very different worlds and asking the same kind of question? – Carl Sagan

It does no harm to the romance of the sunset to know a little bit about it. – Carl Sagan

It doesn’t happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion. – Carl Sagan

It goes with a courageous intent to greet the universe as it really is, not to foist our emotional predispositions on it but to courageously accept what our explorations tell us. – Carl Sagan

It has been said that astronomy is a humbling and character building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we’ve ever known. – Carl Sagan

It is all a matter of time scale. An event that would be unthinkable in a hundred years may be inevitable in a hundred million. – Carl Sagan

It is clear from the fossil record that almost every species that has ever existed is extinct; extinction is the rule, survival is the exception. And no species is guaranteed its tenure on this planet. – Carl Sagan

It is clear that the nations of the world now can only rise and fall together. It is not a question of one nation winning at the expense of another. We must all help one another or all perish together. – Carl Sagan

It is easy to create an interstellar radio message which can be recognized as emanating unambiguously from intelligent beings. A modulated signal (‘beep,’ ‘beep-beep,’…) comprising the numbers 1, 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, for example, consists exclusively of the first 12 prime numbers…. A signal of this kind, based on a simple mathematical concept, could only have a biological origin. … But by far the most promising method is to send pictures. – Carl Sagan

It is far better to grasp the universe as it really is than to persist in delusion, however satisfying and reassuring. – Carl Sagan

It is of interest to note that while some dolphins are reported to have learned English—up to fifty words used in correct context—no human being has been reported to have learned delphinese. – Carl Sagan

It is sometimes said that scientists are unromantic, that their passion to figure out robs the world of beauty and mystery. But is it not stirring to understand how the world actually works—that white light is made of colors, that color is the way we perceive the wavelengths of light, that transparent air reflects light, that in so doing it discriminates among the waves, and that the sky is blue for the same reason that the sunset is red? It does no harm to the romance of the sunset to know a little bit about it. – Carl Sagan

It is the responsibility of scientists never to suppress knowledge, no matter how awkward that knowledge is, no matter how it may bother those in power; we are not smart enough to decide which pieces of knowledge are permissible, and which are not. … – Carl Sagan

It means nothing to be open to a proposition we don’t understand. – Carl Sagan

It pays to keep an open mind, but not so open your brains fall out. – Carl Sagan

It seems madness to say, ‘We’re worried that they’re going to become addicted to marijuana’ — there’s no evidence whatever that it’s an addictive drug, but even if it were, these people are dying, what are we saving them from? – Carl Sagan

It seems to me what is called for is an exquisite balance between two conflicting needs: the most skeptical scrutiny of all hypotheses that are served up to us and at the same time a great openness to ideas. If you are only skeptical, then no new ideas make it through to you. You become a crotchety old person convinced that nonsense is ruling the world. (There is, of course, much data to support you.) But every now and then, a new idea turns out to be on the mark, valid and wonderful. If you are too much in the habit of being skeptical about everything, you are going to miss or resent it, and either way you will be standing in the way of understanding and progress. On the other hand, if you are open to the point of gullibility and have not an ounce of skeptical sense in you, then you cannot distinguish useful ideas from the worthless ones. – Carl Sagan

It seems to me what is called for is an exquisite balance between two conflicting needs: the most skeptical scrutiny of all hypotheses that are served up to us and at the same time a great openness to new ideas … If you are only skeptical, then no new ideas make it through to you … On the other hand, if you are open to the point of gullibility and have not an ounce of skeptical sense in you, then you cannot distinguish the useful ideas from the worthless ones. – Carl Sagan

It took the Church until 1832 to remove Galileo ‘s work from its list of books which Catholics were forbidden to read at the risk of dire punishment of their immortal souls. – Carl Sagan

It will not be we who reach Alpha Centauri, and the other nearby stars. It will be a species very like us – but with more of our strengths and fewer of our weaknesses. – Carl Sagan

It would be wryly interesting if in human history the cultivation of marijuana led generally to the invention of agriculture, and thereby to civilization. – Carl Sagan

It’s better to light a candle then to curse the darkness. – Carl Sagan

Its [science’s] goal is to find out how the world works, to seek what regularities there may be, to penetrate to the connections of things—from subatomic particles, which may be the constituents of all matter, to living organisms, the human social community, and thence to the cosmos as a whole. – Carl Sagan

It’s a lazy Saturday afternoon, there’s a couple lying naked in bed reading Encyclopedia Britannica to each other, and arguing about whether the Andromeda Galaxy is more ‘numinous’ than the Resurrection. Do they know how to have a good time, or don’t they? – Carl Sagan

It’s been said that astronomy is a humbling and, I might add, a character-building experience. – Carl Sagan

It’s hard to kill a creature once it lets you see its consciousness. – Carl Sagan

It’s perilous and foolhardy for the average citizen to remain ignorant about global warming, say, or ozone depletion, air pollution, toxic and radioactive wastes, acid rain, topsoil erosion, tropical deforestation, exponential population growth. Jobs and wages depend on science and technology. – Carl Sagan

It’s sometimes easier to reject strong evidence than to admit that we’ve been wrong, this is information about ourselves worth having. – Carl Sagan

I’ve always thought an agnostic is an atheist without the courage of his convictions. – Carl Sagan

I’ve written a number of books that have to do with the evolution of humans, human intelligence, human emotions. – Carl Sagan

Kepler preferred the hard truth to his dearest illusions, and that is the heart of science. – Carl Sagan

Knowing a great deal is not the same as being smart; intelligence is not information alone but also judgement, the manner in which information is coordinated and used. – Carl Sagan

Looking at fires when high, by the way, especially through one of those prism kaleidoscopes which image their surroundings, is an extraordinarily moving and beautiful experience. – Carl Sagan

Man is a transitional animal. He is not the climax of creation – Carl Sagan

Man is the matter of the cosmos, contemplating itself. – Carl Sagan

Many religions have attempted to make statues of their gods very large, and the idea, I suppose, is to make us feel small. But if that’s their purpose, they can keep their paltry icons. We need only look up if we wish to feel small. – Carl Sagan

Maxwell’s Equations have had a greater impact on human history than any ten presidents. – Carl Sagan

Maybe it’s a little early. Maybe the time is not quite yet. But those other worlds – promising untold opportunities – beckon. Silently, they orbit the Sun, waiting. – Carl Sagan

Modern Darwinism makes it abundantly clear that many less ruthless traits, some not always admired by robber barons and Fuhrers – altruism, general intelligence, compassion – may be the key to survival. – Carl Sagan

Most of the people that I deal with are human. So I’ve had a lot of experience with that. – Carl Sagan

Much of human history can, I think, be described as a gradual and sometimes painful liberation from provincialism, the emerging awareness that there is more to the world than was generally believed by our ancestors. – Carl Sagan

My fundamental premise about the brain is that its workings – what we sometimes call “mind” – are a consequence of its anatomy and physiology, and nothing more. – Carl Sagan

My parents were not scientists. They knew almost nothing about science. But in introducing me simultaneously to skepticism and to wonder, they taught me the two uneasily cohabiting modes of thought that are central to the scientific method. – Carl Sagan

My view is that if there is no evidence for it, then forget about it. An agnostic is somebody who doesn’t believe in something until there is evidence for it, so I’m agnostic. – Carl Sagan

My wonder button is being pushed all the time. – Carl Sagan

National boundaries are not evident when we view the Earth from space. Fanatical ethnic or religious or national chauvinisms are a little difficult to maintain when we see our planet as a fragile blue crescent fading to become an inconspicuous point of light against the bastion and citadel of the stars. – Carl Sagan

Nature does not always conform to our predispositions and preferences, to what we deem comfortable and easy to understand. – Carl Sagan

Nevertheless, (Jefferson) believed that the habit of skepticism is an essential prerequisite for responsible citizenship. He argued that the cost of education is trivial compared to the cost of ignorance, of leaving government to the wolves. He taught that the country is safe only when the people rule. – Carl Sagan

No other planet in the solar system is a suitable home for human beings; it’s this world or nothing. That’s a very powerful perception. – Carl Sagan

No scientist likes to be criticized. … But you don’t reply to critics: Wait a minute, wait a minute; this is a really good idea. I’m very fond of it. It’s done you no harm. Please don’t attack it.” That’s not the way it goes. The hard but just rule is that if the ideas don’t work, you must throw them away. Don’t waste any neurons on what doesn’t work. Devote those neurons to new ideas that better explain the data. Valid criticism is doing you a favor. – Carl Sagan

Nobody listens to mathematicians. – Carl Sagan

Not all birds can fly. What separates the flyers from the walkers is the ability to take off. – Carl Sagan

Not all bits have equal value. – Carl Sagan

Nothing disturbs me more than the glorification of stupidity. – Carl Sagan

Observation: I can’t see a thing. Conclusion: Dinosaurs. – Carl Sagan

On the day that we do discover that we are not alone, our society may begin to evolve and transform in some incredible and wondrous new ways. – Carl Sagan

Once we overcome our fear of being tiny, we find ourselves on the threshold of a vast and awesome Universe that utterly dwarfs — in time, in space, and in potential — the tidy anthropocentric proscenium of our ancestors. – Carl Sagan

Once you give a charlatan power over you, you almost never get it back. – Carl Sagan

One glance at a book and you hear the voice of another person, perhaps someone dead for 1,000 years. To read is to voyage through time. – Carl Sagan

One of the great commandments of science is, ‘Mistrust arguments from authority’. (Scientists, being primates, and thus given to dominance hierarchies, of course do not always follow this commandment.) – Carl Sagan

One of the great commandments of science is: ‘Mistrust arguments from authority.’ – Carl Sagan

One of the greatest gifts adults can give – to their offspring and to their society – is to read to children.

One of the reasons for its success is that science has a built-in, error-correcting machinery at its very heart. Some may consider this an overboard characterization, but to me every time we exercise self-criticism, every time we test our ideas against the outside world, we are doing science. When we are self-indulgent and uncritical, when we confuse hopes and facts, we slide into pseudoscience and superstition. – Carl Sagan

One of the saddest lessons of history is this: If we’ve been bamboozled long enough, we tend to reject any evidence of the bamboozle. We’re no longer interested in finding out the truth. The bamboozle has captured us. It’s simply too painful to acknowledge, even to ourselves, that we’ve been taken. Once you give a charlatan power over you, you almost never get it back. – Carl Sagan

One of the saddest lessons of history is this: If we’ve been bamboozled long enough, we tend to reject any evidence of the bamboozle. We’re no longer interested in finding out the truth. The bamboozle has captured us. – Carl Sagan

One trend that bothers me is the glorification of stupidity, that the media is reassuring people it’s alright not to know anything. That to me is far more dangerous than a little pornography on the Internet. – Carl Sagan

One’s inability to invalidate your hypothesis is not at all the same thing as proving it true. – Carl Sagan

Organic as a dandelion seed, [the ship of our imagination] will carry us to worlds of dreams and worlds of facts – Carl Sagan

Other things being equal, if you can figure the world out, you have a better chance of survival. At least until the invention of nuclear weapons. – Carl Sagan

Other things being equal, it is better to be smart than to be stupid. – Carl Sagan

Otherwise we don’t run the government the government runs us – Carl Sagan

Our ancestors lived out of doors. They were as familiar with the night sky as most of us are with our favorite television programs. – Carl Sagan

Our ancestors worshipped the Sun, and they were not that foolish. It makes sense to revere the Sun and the stars, for we are their children. – Carl Sagan

Our ancestors worshipped the Sun, and they were not that foolish.
It makes sense to revere the Sun and the stars, for we are their children. – Carl Sagan

Our children long for realistic maps of the future that they can be proud of. Where are the cartographers of human purpose? – Carl Sagan

Our concern for the future can be tested by how well we support our libraries. – Carl Sagan

Our intelligence is imperfect, surely, and newly arisen; the ease with which it can be sweet-talked, overwhelmed, or subverted by other hardwired propensities – sometimes themselves disguised as the cool light of reason – is worrisome. – Carl Sagan

Our obligation to survive and flourish is owed not just to ourselves, but also to the cosmos, ancient and vast, from which we spring. – Carl Sagan

Our passion for learning … is our tool for survival. – Carl Sagan

Our perceptions are fallible. We sometimes see what isn’t there. We are prey to optical illusions. Occasionally we hallucinate. We are error-prone. – Carl Sagan

Our posturing, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves. – Carl Sagan

Our posturings, our imagined self-importance , the delusion that we have some privileged position in the universe are challenged by this point of pale light. – Carl Sagan

Our posturings, our imagined self-importance, the delusion that we have some privileged position in the universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. – Carl Sagan

Our species needs, and deserves, a citizenry with minds wide awake and a basic understanding of how the world works. – Carl Sagan

Ours is the first generation that has grown up with science-fiction ideas. – Carl Sagan

People are not stupid. They believe things for reasons. The last way for skeptics to get the attention of bright, curious, intelligent people is to belittle or condescend or to show arrogance toward their beliefs. – Carl Sagan

Perhaps, in retrospect, there would be little motivation even for malevolent extraterrestrials to attack the Earth; perhaps, after a preliminary survey, they might decide it is more expedient just to be patient for a little while and wait for us to self-destruct. – Carl Sagan

Present global culture is a kind of arrogant newcomer. It arrives on the planetary stage following four and a half billion years of other acts, and after looking about for a few thousand years declares itself in possession of eternal truths. But in a world that is changing as fast as ours, this is a prescription for disaster. No nation, no religion, no economic system, no body of knowledge, is likely to have all the answers for our survival. There must be many social systems that would work far better than any now in existence. In the scientific tradition, our task is to find them. – Carl Sagan

Preserve and cherish the pale blue dot, the only home we’ve ever known. – Carl Sagan

Probably a dozen times since their death I’ve heard my mother or father, in an ordinary conversational tone of voice, call my name. They had called my name often during my life with them … It doesn’t seem strange to me. – Carl Sagan

Quickly capping 363 oil well fires in a war zone is impossible. The fires would burn out of control until they put themselves out… The resulting soot might well stretch over all of South Asia… It could be carried around the world… [and] the consequences could be dire. Beneath such a pall sunlight would be dimmed, temperatures lowered and droughts more frequent. Spring and summer frosts may be expected… This endangerment of the food supplies… appears to be likely enough that it should affect the war plans… – Carl Sagan

Real patriots ask questions. – Carl Sagan

Recent research shows that many children who do not have enough to eat wind up with diminished capacity to understand and learn. Children don’t have to be starving for this to happen. Even mild undernutrition – the kind most common among poor people in America – can do it. – Carl Sagan

Sailors on a becalmed sea, we sense the stirring of a breeze. – Carl Sagan

Science is an ongoing process. It never ends. There is no single ultimate truth to be achieved, after which all the scientists can retire. – Carl Sagan

Science is more than a body of knowledge; it is a way of thinking. – Carl Sagan

Science is not perfect. It can be misused. It is only a tool. But it is by far the best tool we have, self-correcting, ongoing, applicable to everything. It has two rules. First: there are no sacred truths; all assumptions must be critically examined; arguments from authority are worthless. Second: whatever is inconsistent with the facts must be discarded or revised. … The obvious is sometimes false; the unexpected is sometimes true. – Carl Sagan

She had studied the universe all her life, but had overlooked its clearest message: For small creatures such as we the vastness is bearable only through love. – Carl Sagan

Since, in the long run, every planetary civilization will be endangered by impacts from space, every surviving civilization is obliged to become spacefaring–not because of exploratory or romantic zeal, but for the most practical reason imaginable: staying alive… If our long-term survival is at stake, we have a basic responsibility to our species to venture to other worlds. – Carl Sagan

So those who wished for some central cosmic purpose for us, or at least our world, or at least our solar system, or at least our galaxy, have been disappointed, progressively disappointed. The universe is not responsive to our ambitious expectations. – Carl Sagan

Societies will, of course, wish to exercise prudence in deciding which technologies that is, which applications of science are to be pursued and which not. But without funding basic research, without supporting the acquisition of knowledge for its own sake, our options become dangerously limited. – Carl Sagan

Some ideas are better than others. The machinery for distinguishing them is an essential tool in dealing with the world and especially in dealing with the future. And it is precisely the mix of these two modes of thought [skeptical scrutiny and openness to new ideas] that is central to the success of science. – Carl Sagan

Some racists still reject the plain testimony written in the DNA that all the races are not only human but nearly indistinguishable. . . .

Somewhere, something incredible is waiting to be known. – Carl Sagan

Somewhere, there is something incredible waiting to be known. – Carl Sagan

Star stuff contemplating star stuff … – Carl Sagan

Stars are phoenixes, rising from their own ashes. – Carl Sagan

Teller contended, not implausibly, that hydrogen bombs keep the peace, or at least prevent thermonuclear war, because the consequences of warfare between nuclear powers are now too dangerous. We haven’t had a nuclear war yet, have we? But all such arguments assume that the nuclear-armed nations are and always will be, without exception, rational actors, and that bouts of anger and revenge and madness will never overtake their leaders (or military and secret police officers in charge of nuclear weapons). In the century of Hitler and Stalin, this seems ingenuous. – Carl Sagan

That kind of skeptical, questioning, “don’t accept what authority tells you” attitude of science – is also nearly identical to the attitude of mind necessary for a functioning democracy. Science and democracy have very consonant values and approaches, and I don’t think you can have one without the other. – Carl Sagan

That we can now think of no mechanism for astrology is relevant but unconvincing. No mechanism was known, for example, for continental drift when it was proposed by Wegener. Nevertheless, we see that Wegener was right, and those who objected on the grounds of unavailable mechanism were wrong. – Carl Sagan

The absence of evidence is not the evidence of absence. – Carl Sagan

The Apollo pictures of the whole Earth conveyed to multitudes something well known to astronomers: On the scale of the worlds – to say nothing of stars or galaxies – humans are inconsequential, a thin film of life on an obscure and solitary lump of rock and metal – Carl Sagan

The beginning of morality is to see the world as it is. – Carl Sagan

The Big Bang is our modern scientific creation myth. It comes from the same human need to solve the cosmological riddle [Where did the universe come from?] – Carl Sagan

The brain is like a muscle. When it is in use we feel very good. Understanding is joyous. – Carl Sagan

The candle flame gutters. Its little pool of light trembles. Darkness gathers. The demons begin to stir. – Carl Sagan

The cannabis experience has greatly improved my appreciation for art, a subject which I had never much appreciated before. – Carl Sagan

The chief deficiency I see in the skeptical movement is its polarization: Us vs. Them – the sense that we have a monopoly on the truth; that those other people who believe in all these stupid doctrines are morons; that if you’re sensible, you’ll listen to us; and if not, to hell with you. This is nonconstructive. It does not get our message across. It condemns us to permanent minority status. – Carl Sagan

The claim is also sometimes made that science is as arbitrary or irrational as all other claims to knowledge, or that reason itself is an illusion. As Ethan Allen said Those who invalidate reason ought seriously to consider whether they argue against reason with or without reason; if with reason, then they establish the principle that they are labouring to dethrone. If they argue without reason, which they must do, in order to be consistent with themselves, they are out of reach of rational conviction, nor do they deserve a rational argument. – Carl Sagan

The cosmic calendar compresses the local history of the universe into a single year. If the universe began on January 1st it was not until May that the Milky Way formed. Other planetary systems may have appeared in June, July and August, but our Sun and Earth not until mid-September. Life arose soon after. We humans appear on the cosmic calendar so recently that our recorded history occupies only the last few seconds of the last minute of December 31st – Carl Sagan

The Cosmos is all that is or was or ever will be. Our feeblest contemplations of the Cosmos stir us — there is a tingling in the spine, a catch in the voice, a faint sensation, as if a distant memory, of falling from a height. We know we are approaching the greatest of mysteries. – Carl Sagan

The cosmos is all that is, or ever was, or ever will be. – Carl Sagan

The cosmos is all there is, all there ever was, and all there ever will be. – Carl Sagan

The cosmos is full beyond measure of elegant truths / of exquisite interrelationships / of the awesome machinery of nature – Carl Sagan

The cosmos is within us. We are made of star stuff. – Carl Sagan

The cosmos is within us. We are made of star-stuff. We are a way for the universe to know itself. – Carl Sagan

The cure for a fallacious argument is a better argument, not the suppression of ideas. – Carl Sagan

The dangers of not thinking clearly are much greater now than ever before. It’s not that there’s something new in our way of thinking – it’s that credulous and confused thinking can be much more lethal in ways it was never before. – Carl Sagan

The deflation of some of our more common conceits is one of the practical applications of astronomy. – Carl Sagan

The desire to be connected with the cosmos reflects a profound reality, but we are connected; not in the trivial ways that astrology promises, but in the deepest ways. – Carl Sagan

The difference between physics and metaphysics is not that the practitioners of one are smarter than the practitioners of the other. The difference is that the metaphysicist has no laboratory. – Carl Sagan

The dumbing down of America is evident in the slow decay of substantive content, a kind of celebration of ignorance. – Carl Sagan

The dumbing down of American is most evident in the slow decay of substantive content in the enormously influential media, the 30 second sound bites (now down to 10 seconds or less), lowest common denominator programming, credulous presentations on pseudoscience and superstition, but especially a kind of celebration of ignorance. – Carl Sagan

The evidence, so far at least and laws of Nature aside, does not require a Designer. Maybe there is one hiding, maddeningly unwilling to be revealed. – Carl Sagan

The fact that so little of the findings of modern science is prefigured in Scripture to my mind casts further doubt on it divine inspiration. – Carl Sagan

The fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. – Carl Sagan

The fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown. – Carl Sagan

The fact that someone says something doesn’t mean it’s true. Doesn’t mean they’re lying, but it doesn’t mean it’s true. – Carl Sagan

The fossil record implies trial and error, the inability to anticipate the future, features inconsistent with a Great Designer (though not a Designer of a more remote and indirect temperament.) – Carl Sagan

The gears of poverty, ignorance, hopelessness and low self-esteem interact to create a kind of perpetual failure machine that grinds down dreams from generation to generation. We all bear the cost of keeping it running. Illiteracy is its linchpin. – Carl Sagan

The hole in the ozone layer is a kind of skywriting. At first it seemed to spell out our continuing complacency before a witch’s brew of deadly perils. But perhaps it really tells of a newfound talent to work together to protect the global environment. – Carl Sagan

The illegality of cannabis is outrageous, an impediment to full utilization of a drug which helps produce the serenity and insight, sensitivity and fellowship so desperately needed in this increasingly mad and dangerous world. – Carl Sagan

The illegality of cannabis is outrageous… – Carl Sagan

The immense distances to the stars and the galaxies mean that we see everything ins pace int he past, some as they were before the Earth came to be. Telescopes are time machines. – Carl Sagan

The impediment to scientific thinking is not, I think, the difficulty of the subject. Complex intellectual feats have been mainstays even of oppressed cultures. Shamans, magicians and theologians are highly skilled in their intricate and arcane arts. No, the impediment is political and hierarchical. – Carl Sagan

The library connects us with the insight and knowledge, painfully extracted from Nature, of the greatest minds that ever were, with the best teachers, drawn from the entire planet and from all our history, to instruct us without tiring, and to inspire us to make our own contribution to the collective knowledge of the human species. – Carl Sagan

The lifetime of a human being is measured by decades, the lifetime of the Sun is a hundred million times longer. Compared to a star, we are like mayflies, fleeting ephemeral creatures who live out their lives in the course of a single day. – Carl Sagan

The near side of a galaxy is tens of thousands of light-years closer to us than the far side; thus we see the front as it was tens of thousands of years before the back. But typical events in galactic dynamics occupy tens of millions of years, so the error in thinking of an image of a galaxy as frozen in one moment of time is small. – Carl Sagan

The neurochemistry of the brain is astonishingly busy, the circuitry of a machine more wonderful than any devised by humans. But there is no evidence that its functioning is due to anything more than the 10 14 neural connections that build an elegant architecture of consciousness. – Carl Sagan

The notion that science and spirituality are somehow mutually exclusive does a disservice to both. – Carl Sagan

The nuclear arms race is like two sworn enemies standing waist deep in gasoline, one with three matches, the other with five. – Carl Sagan

The old appeals to racial, sexual and religious chauvinism to rabid nationalist fervor, are beginning not to work. – Carl Sagan

The open road still softly calls, like a nearly forgotten song of childhood – Carl Sagan

The open road still softly calls… – Carl Sagan

The passion to explore is at the heart of being human. – Carl Sagan

The politicians and the religious leaders and the weapons scientists have been at it for a long time and they’ve made a thorough mess of it. I mean, we’re in deep trouble. – Carl Sagan

The prediction I can make with the highest confidence is that the most amazing discoveries will be the ones we are not today wise enough to foresee. – Carl Sagan

The prediction of nuclear winter is drawn not, of course, from any direct experience with the consequences of global nuclear war, but rather from an investigation of the governing physics. – Carl Sagan

The price we pay for anticipation of the future is anxiety about it – Carl Sagan

The professed function of the nuclear weapons on each side is to prevent the other side from using their nuclear weapons. If that’s all it is, then we’ve gotta as: how many nuclear weapons do you need to do that? – Carl Sagan

The reappearance of the crescent moon after the new moon; the return of the Sun after a total eclipse, the rising of the Sun in the morning after its troublesome absence at night were noted by people around the world; these phenomena spoke to our ancestors of the possibility of surviving death. Up there in the skies was also a metaphor of immortality. – Carl Sagan

The Romans called the Christians atheists. Why? Well, the Christians had a god of sorts, but it wasn’t a real god. They didn’t believe in the divinity of apotheosized emperors or Olympian gods. They had a peculiar, different kind of god. So it was very easy to call people who believed in a different kind of god atheists. And that general sense that an atheist is anybody who doesn’t believe exactly as I do prevails in our own time. – Carl Sagan

The sacred truth of science is that there are no sacred truths. – Carl Sagan

The scientific cast of mind examines the world critically, as if many alternative worlds might exist, as if other things might be here which are not. Then we are forced to ask why what we see is present and not something else. Why are the Sun and moon and the planets spheres? Why not pyramids, or cubes, or dodecahedra? Why not irregular, jumbly shapes? Why so symmetrical, worlds? If you spend any time spinning hypotheses, checking to see whether they make sense, whether they conform to what else we know. Thinking of tests you can pose to substantiate or deflate hypotheses, you will find yourself doing science. – Carl Sagan

The secrets of evolution are death and time—the deaths of enormous numbers of lifeforms that were imperfectly adapted to the environment; and time for a long succession of small mutations. – Carl Sagan

The simplest thought, like the concept of the number one, has an elaborate logical underpinning. – Carl Sagan

The size and age of the Cosmos are beyond ordinary human understanding. Lost somewhere between immensity and eternity is our tiny planetary home. – Carl Sagan

The sky calls to us. If we do not destroy ourselves, we will one day venture to the stars. – Carl Sagan

The surface of the Earth is the shore of the cosmic ocean. – Carl Sagan

The surface of the Earth is the shore of the cosmic ocean. On this shore, we’ve learned most of what we know. Recently, we’ve waded a little way out, maybe ankle-deep, and the water seems inviting. Some part of our being knows this is where we came from. We long to return, and we can, because the cosmos is also within us. We’re made of star stuff. We are a way for the cosmos to know itself. – Carl Sagan

The testimony of our common sense is suspect at high velocities. – Carl Sagan

The total number of stars in the Universe is larger than all the grains of sand on all the beaches of the planet Earth. – Carl Sagan

The truth may be puzzling. It may take some work to grapple with. It may be counterintuitive. It may contradict deeply held prejudices. It may not be consonant with what we desperately want to be true. But our preferences do not determine what’s true. We have a method, and that method helps us to reach not absolute truth, only asymptotic approaches to the truth—never there, just closer and closer, always finding vast new oceans of undiscovered possibilities. Cleverly designed experiments are the key. – Carl Sagan

The truth may be puzzling. It may take some work to grapple with. It may be counterintuitive. It may contradict deeply held prejudices. It may not be consonant with what we desperately want to be true. But our preferences do not determine what’s true. – Carl Sagan

The universe forces those who live in it to understand it. – Carl Sagan

The Universe forces those who live in it to understand it. Those creatures who find everyday experience a muddled jumble of events with no predictability, no regularity, are in grave peril. The Universe belongs to those who, at least to some degree, have figured it out. – Carl Sagan

The universe is a pretty big place. If it’s just us, seems like an awful waste of space. – Carl Sagan

The universe is not required to be in perfect harmony with human ambition. – Carl Sagan

The universe seems neither benign nor hostile, merely indifferent. – Carl Sagan

The universe was made on purpose, the circle said. In whatever galaxy you happen to find yourself, you take the circumference of a circle, divide it by its diameter, measure closely enough, and uncover a miracle — another circle, drawn kilometers downstream of the decimal point. There would be richer messages farther in. It doesn’t matter what you look like, or what you’re made of, or where you come from. As long as you live in this universe, and have a modest talent for mathematics, sooner or later you’ll find it. It’s already here. It’s inside everything. You don’t have to leave your planet to find it. In the fabric of space and in the nature of matter, as in a great work of art, there is, written small, the artist’s signature. Standing over humans, gods, and demons, subsuming Caretakers and Tunnel builders, there is an intelligence that antedates the universe. – Carl Sagan

The usual rejoinder to someone who says ‘They laughed at Columbus, they laughed at Galileo’ is to say ‘But they also laughed at Bozo the Clown’. – Carl Sagan

The vast distances that separate the stars are providential. Beings and worlds are quarantined from one another. The quarantine is lifted only for those with sufficient self-knowledge and judgment to have safely traveled from star to star. – Carl Sagan

The very act of understanding is a celebration of joining, merging, even if on a very modest scale, with the magnificence of the Cosmos. – Carl Sagan

The visions we offer our children shape the future. – Carl Sagan

The visions we offer our children shape the future. It _matters_ what those visions are. Often they become self-fulfilling prophecies. Dreams are maps. – Carl Sagan

The way to find out about our place in the universe is by examining the universe and by examining ourselves – without preconceptions, with as unbiased a mind as we can muster. – Carl Sagan

The well-meaning contention that all ideas have equal merit seems to me little different from the disastrous contention that no ideas have any merit. – Carl Sagan

The wind whips through the canyons of the American Southwest, and there is no one to hear it but us – a reminder of the 40,000 generations of thinking men and women who preceded us, about whom we know almost nothing, upon whom our civilization is based. – Carl Sagan

The words “question” and “quest” are cognates. Only through inquiry can we discover truth. – Carl Sagan

There are as many atoms in one molecule of DNA as there are stars in a typical galaxy. – Carl Sagan

There are huge advertising budgets only when there’s no difference between the products. If the products really were different, people would buy the one that’s better. Advertising teaches people not to trust their judgment. Advertising teaches people to be stupid. – Carl Sagan

There are in fact 100 billion galaxies, each of which contain something like a 100 billion stars. Think of how many stars, and planets, and kinds of life there may be in this vast and awesome universe. – Carl Sagan

There are lots of ways to communicate what we know, but few ways to communicate what we feel. Music is one way to communicate emotions. – Carl Sagan

There are many hypotheses in physics of almost comparable brilliance and elegance that have been rejected because they did not survive such a confrontation with experiment. In my view, the human condition would be greatly improved if such confrontations and willingness to reject hypotheses were a regular part of our social, political, economic, religious and cultural lives. – Carl Sagan

There are many hypotheses in science which are wrong. That’s perfectly all right: it’s the aperture to finding out what’s right. Science is a self-correcting process. – Carl Sagan

There are many other (besides testosterone) behaviour-eliciting hormones fundamental for human well-being, including estrogen and progesterone in females. The fact that complex behavioral patterns can be triggered by a tiny concentration of molecules coursing through the bloodstream, and that different animals of the same species generate different amounts of these hormones, is something worth thinking about when it’s time to judge such matters as free will, individual responsibility, and law and order. – Carl Sagan

There are more potential combinations of DNA [physical forms] than there are atoms in the universe. – Carl Sagan

There are naive questions, tedious questions, ill-phrased questions, questions put after inadequate self-criticism. But every question is a cry to understand the world. There is no such thing as a dumb question. – Carl Sagan

There are no forbidden questions in science, no matters too sensitive or delicate to be probed, no sacred truths. – Carl Sagan

There are wonders enough out there without our inventing any. – Carl Sagan

There is a lurking fear that some things are not meant to be known. – Carl Sagan

There is a lurking fear that some things are not meant” to be known, that some inquiries are too dangerous for human beings to make. – Carl Sagan

There is a place with four suns in the sky—red, white, blue, and yellow; two of them are so close together that they touch, and star-stuff flows between them. I know of a world with a million moons. I know of a sun the size of the Earth—and made of diamond. There are atomic nuclei a few miles across which rotate thirty times a second. There are tiny grains between the stars, with the size and atomic composition of bacteria. There are stars leaving the Milky Way, and immense gas clouds falling into it. There are turbulent plasmas writhing with X- and gamma-rays and mighty stellar explosions. There are, perhaps, places which are outside our universe. The universe is vast and awesome, and for the first time we are becoming a part of it. – Carl Sagan

There is a report that says that kids who watch violent TV programs tend to be more violent when they grow up. But did the TV cause the violence, or do violent children preferentially enjoy watching violent programs? – Carl Sagan

There is a reward structure in science that is very interesting: Our highest honors go to those who disprove the findings of the most revered among us. So Einstein is revered not just because he made so many fundamental contributions to science, but because he found an imperfection in the fundamental contribution of Isaac Newton. – Carl Sagan

There is a wide, yawning black infinity. In every direction, the extension is endless; the sensation of depth is overwhelming. And the darkness is immortal. Where light exists, it is pure, blazing, fierce; but light exists almost nowhere, and the blackness itself is also pure and blazing and fierce. – Carl Sagan

There is another approach to the extraterrestrial hypothesis of UFO origins. This assessment depends on a large number of factors about which we know little, and a few about which we know literally nothing. I want to make some crude numerical estimate of the probability that we are frequently visited by extraterrestrial beings.
Now, there is a range of hypotheses that can be examined in such a way. Let me give a simple example: Consider the Santa Claus hypothesis, which maintains that, in a period of eight hours or so on December 24-25 of each year, an outsized elf visits one hundred million homes in the United States. This is an interesting and widely discussed hypothesis. Some strong emotions ride on it, and it is argued that at least it does no harm.
We can do some calculations. Suppose that the elf in question spends one second per house. This isn’t quite the usual picture—“Ho, Ho, Ho,” and so on—but imagine that he is terribly efficient and very speedy; that would explain why nobody ever sees him very much-only one second per house, after all. With a hundred million houses he has to spend three years just filling stockings. I have assumed he spends no time at all in going from house to house. Even with relativistic reindeer, the time spent in a hundred million houses is three years and not eight hours. This is an example of hypothesis-testing independent of reindeer propulsion mechanisms or debates on the origins of elves. We examine the hypothesis itself, making very straightforward assumptions, and derive a result inconsistent with the hypothesis by many orders of magnitude. We would then suggest that the hypothesis is untenable.
We can make a similar examination, but with greater uncertainty, of the extraterrestrial hypothesis that holds that a wide range of UFOs viewed on the planet Earth are space vehicles from planets of other stars. – Carl Sagan

There is every reason to think that in the coming years Mars and its mysteries will become increasingly familiar to the inhabitants of the Planet Earth. – Carl Sagan

There is in this Universe much of what seems to be design. – Carl Sagan

There is much about which even experts are ignorant; this will probably always be the case. – Carl Sagan

There is much that science doesn’t understand, many mysteries still to be resolved. In a Universe tens of billions of light-years across and some ten or fifteen billion years old, this may be the case forever. We are constantly stumbling on new surprises – Carl Sagan

There is never only ONE of anything in nature. – Carl Sagan

There is no other species on Earth that does science. It is, so far, entirely a human invention, evolved by natural selection in the cerebral cortex for one simple reason: it works. It is not perfect. It can be misused. It is only a tool. But it is by far the best tool we have, self-correcting, ongoing, applicable to everything. – Carl Sagan

There is perhaps no better a demonstration of the folly of human conceits than this distant image of our tiny world. – Carl Sagan

These are all cases of proved or presumptive baloney. A deception arises, sometimes innocently but collaboratively, sometimes with cynical premeditation. Usually the victim is caught up in a powerful emotion — wonder, fear, greed, grief. Credulous acceptance of baloney can cost you money; that’s what P. T. Barnum meant when he said, ‘There’s a sucker born every minute.’ But it can be much more dangerous than that, and when governments and societies lose the capacity for critical thinking, the results can be catastrophic — however sympathetic we may be to those who have bought the baloney. – Carl Sagan

These days there seems to be nowhere left to explore, at least on the land area of the Earth. Victims of their very success, the explorers now pretty much stay home. – Carl Sagan

Think of the rivers of blood spilled by all those generals and emperors so that in glory and in triumph they could become the ‘Momentary’ masters of a ‘Fraction’ of a ‘Dot’. – Carl Sagan

This oak tree and me, we’re made of the same stuff. – Carl Sagan

Those afraid of the universe as it really is, those who pretend to nonexistent knowledge and envision a Cosmos centered on human beings will prefer the fleeting comforts of superstition. They avoid rather than confront the world. But those with the courage to explore the weave and structure of the Cosmos, even where it differs profoundly from their wishes and prejudices, will penetrate its deepest mysteries. – Carl Sagan

Those at too great a distance may, I am well are, mistake ignorance for perspective. – Carl Sagan

Those who seek power at any price detect a societal weakness, a fear that they can ride into office. – Carl Sagan

Those with the courage to explore the weave and structure of the Cosmos, even where it differs profoundly from their wishes and prejudices, will penetrate its deepest mysteries. – Carl Sagan

Thus the recent rapid evolution of human intelligence is not only the cause of but also the only conceivable solution to the many serious problems that beset us. – Carl Sagan

Time spent with children is time well spent. Their little minds are not constrained by ‘reality’ or focused upon goals. Anything and everything is possible. Imagination will often carry us to worlds that never were. But without it we go nowhere. – Carl Sagan

To live in the hearts of others is to never die in those we leave behind. – Carl Sagan

To read is to voyage through time. – Carl Sagan

Today, we’re still loaded down – and, to some extent, embarrassed – by ancient myths, but we respect them as part of the same impulse that has led to the modern, scientific kind of myth. But we now have the opportunity to discover, for the first time, the way the universe is in fact constructed as opposed to how we would wish it to be constructed. – Carl Sagan

Too much openness and you accept every notion, idea, and hypothesis—which is tantamount to knowing nothing. Too much skepticism—especially rejection of new ideas before they are adequately tested—and you’re not only unpleasantly grumpy, but also closed to the advance of science. A judicious mix is what we need. – Carl Sagan

Understanding is a kind of ecstasy. – Carl Sagan

Valid criticism does you a favor. – Carl Sagan

War is murder writ large. – Carl Sagan

We are a way for the cosmos to know itself. – Carl Sagan

We are all made up of star stuff. – Carl Sagan

We are all star stuff. – Carl Sagan

We are an intelligent species and the use of our intelligence quite properly gives us pleasure. In this respect the brain is like a muscle. When we think well, we feel good. Understanding is a kind of ecstasy. – Carl Sagan

We are at a crossroads in human history. Never before has there been a moment so simultaneously perilous and promising. We are the first species to have taken evolution into our own hands. – Carl Sagan

We are like butterflies who flutter for a day and think it is forever. – Carl Sagan

We are like the inhabitants of an isolated valley in New Guinea who communicate with societies in neighboring valleys (quite different societies, I might add) by runner and by drum. When asked how a very advanced society will communicate, they might guess by an extremely rapid runner or by an improbably large drum. They might not guess a technology beyond their ken. And yet, all the while, a vast international cable and radio traffic passes over them, around them, and through them… We will listen for the interstellar drums, but we will miss the interstellar cables. We are likely to receive our first messages from the drummers of the neighboring galactic valleys – from civilizations only somewhat in our future. The civilizations vastly more advanced than we, will be, for a long time, remote both in distance and in accessibility. At a future time of vigorous interstellar radio traffic, the very advanced civilizations may be, for us, still insubstantial legends. – Carl Sagan

We are made of star stuff. For the most part, atoms heavier than hydrogen were created in the interiors of stars and then expelled into space to be incorporated into later stars. The Sun is probably a third generation star. – Carl Sagan

We are made of star-stuff. Our bodies are made of star-stuff. There are pieces of star within us all. – Carl Sagan

We are made of stellar ash. Our origin and evolution have been tied to distant cosmic events. The exploration of the cosmos is a voyage of self-discovery. – Carl Sagan

We are not smart enough to decide which pieces of knowledge are permissible and which are not. – Carl Sagan

We are not without empathetic terror when we open Pascal’s ‘Pensees’ and read, ‘I am the great silent spaces between worlds.’ – Carl Sagan

We are one species. We are starstuff. – Carl Sagan

We are prodding, challenging, seeking contradictions or small, persistent residual errors, proposing alternative explanations, encouraging heresy. We give our highest rewards to those who convincingly disprove established beliefs. – Carl Sagan

We are rare and precious because we are alive, because we can think as well as we can. We are privileged to influence and perhaps control our future. I believe we have an obligation to fight for life on Earth – not just for ourselves, but for all those, humans and others, who came before us, and to whom we are beholden, and for all those who, if we are wise enough, will come after. – Carl Sagan

We are star stuff harvesting sunlight. – Carl Sagan

We are star stuff which has taken its destiny into its own hands. – Carl Sagan

We are star stuff which has taken its destiny into its own hands. The loom of time and space works the most astonishing transformations of matter. – Carl Sagan

We are the children equally of the Sky and the Earth. – Carl Sagan

We are the first species to have taken our evolution into our own hands. – Carl Sagan

We are the local embodiment of a Cosmos grown to self-awareness. We have begun to contemplate our origins: starstuff pondering the stars; organized assemblages of ten billion billion billion atoms considering the evolution of atoms; tracing the long journey by which, here at least, consciousness arose. Our loyalties are to the species and the planet. We speak for Earth. Our obligation to survive is owed not just to ourselves but also to that Cosmos, ancient and vast, from which we spring. – Carl Sagan

We are the only species on the planet, so far as we know, to have invented a communal memory stored neither in our genes nor in our brains. The warehouse of this memory is called the library – Carl Sagan

We are the product of 4.5 billion years of fortuitous, slow biological evolution. There is no reason to think that the evolutionary process has stopped. Man is a transitional animal. He is not the climax of creation. – Carl Sagan

We are the representatives of the cosmos; we are an example of what hydrogen atoms can do, given 15 billion years of cosmic evolution. – Carl Sagan

We are the universe experiencing itself. – Carl Sagan

We are, each of us, a multitude. Within us is a little universe. – Carl Sagan

We are, in the most profound sense, children of the Cosmos. – Carl Sagan

We began as wanderers, and we are wanderers still. – Carl Sagan

We can always take but never give. – Carl Sagan

We can judge our progress by the courage of our questions and the depth of our answers, our willingness to embrace what is true rather than what feels good. – Carl Sagan

We can make a similar examination, but with greater uncertainty, of the extraterrestrial hypothesis that holds that a wide range of UFOs viewed on the planet Earth are space vehicles from planets of other stars. – Carl Sagan

We go about our daily lives understanding almost nothing of the world. – Carl Sagan

We have begun to contemplate our origins: starstuff pondering the stars; organized assemblages of ten billion billion billion atoms considering the evolution of atoms; tracing the long journey by which, here at least, consciousness arose. – Carl Sagan

We have begun to contemplate our origins: starstuff pondering the stars; organized assemblages of ten billion billion billion atoms considering the evolution of atoms; tracing the long journey by which, here at least, consciousness arose. Our loyalties are to the species and the planet. We speak for Earth. Our obligation to survive is owed not just to ourselves but also to that Cosmos, ancient and vast, from which we spring. – Carl Sagan

We have entered, almost without noticing, an age of exploration and discovery unparalleled since the Renaissance. – Carl Sagan

We have heard the rationales offered by the nuclear superpowers. We know who speaks for the nations. But who speaks for the human species? Who speaks for Earth? – Carl Sagan

We humans appear on the cosmic calendar so recently that our recorded history occupies only the last few seconds of the last minute of December 31st. – Carl Sagan

We live at a moment when our relationships to each other, and to all other beings with whom we share this planet, are up for grabs. – Carl Sagan

We live in a society absolutely dependent on science and technology and yet have cleverly arranged things so that almost no one understands science and technology. That’s a clear prescription for disaster. – Carl Sagan

We live in an in-between universe where things change all right…but according to patterns, rules, or as we call them, laws of nature. – Carl Sagan

We live on a hunk of rock and metal that circles a humdrum star that is one of 400 billion other stars that make up the Milky Way Galaxy which is one of billions of other galaxies which make up a universe which may be one of a very large number, perhaps an infinite number, of other universes. That is a perspective on human life and our culture that is well worth pondering. – Carl Sagan

We live on a mote of dust suspended in a sunbeam. – Carl Sagan

We live on an obscure hunk of rock and metal circling a humdrum sun, which is on the outskirts of a perfectly ordinary galaxy comprised of 400 billion other suns, which, in turn, is one of some hundred billion galaxies that make up the universe, which, current thinking suggests, is one of a huge number—perhaps an infinite number—of other closed-off universes. From that perspective, the idea that we’re at the center, that we have some cosmic importance, is ludicrous. – Carl Sagan

We make our world significant by the courage of our questions and by the depth of our answers. – Carl Sagan

We must understand the Cosmos as it is and not confuse how it is with how we wish it to be. – Carl Sagan

We seem, these days, much more willing to recognize the perils before us than we were even a decade ago. The newly recognized dangers threaten all of us, equally. No one can say how it will turn out down here. But this is also, we may note, the first time that a species has become able to journey to the planets and the stars. Sailors on a becalmed sea, we sense a stirring of the breeze. – Carl Sagan

We should be teaching our children the scientific method and the reasons for a Bill of Rights. With it comes a certain decency, humility and community spirit. – Carl Sagan

We start out a million years ago in a small community on some grassy plain; we hunt animals, have children, and develop a rich social, sexual, and intellectual life, but we know almost nothing about our surroundings. – Carl Sagan

We tend not to be especially critical when presented with evidence that seems to confirm our prejudices. – Carl Sagan

We were wanderers from the beginning. – Carl Sagan

We wish to find the truth, no matter where it lies. But to find the truth we need imagination and skepticism both. We will not be afraid to speculate, but we will be careful to distinguish speculation from fact. – Carl Sagan

We’ve arranged a civilization in which most crucial elements profoundly depend on science and technology. – Carl Sagan

We’ve arranged a global civilization in which most critical elements profoundly depend on science and technology. We have also arranged things so that almost no one understands science and technology. This is a prescription for disaster. We might get away with it for a while, but sooner or later this combustible mixture of ignorance and power is going to blow up in our faces. – Carl Sagan

We’re in very bad trouble if we don’t understand the planet we’re trying to save. – Carl Sagan

We’ve arranged a civilization in which most crucial elements profoundly depend on science and technology. – Carl Sagan

We’ve begun at last to wonder about our origins, star stuff contemplating the stars, organized collections of ten billion billion billion atoms contemplating the evolution of matter, tracing that long path by which it arrived at consciousness here on the planet Earth and perhaps throughout the cosmos. Our obligation to survive and flourish is owed not just to ourselves but also to that cosmos, ancient and vast, from which we spring. – Carl Sagan

We’ve tended in our cosmologies to make things familiar. Despite all our best efforts, we’ve not been very inventive. In the West, Heaven is placid and fluffy, and Hell is like the inside of a volcano. In many stories, both realms are governed by dominance hierarchies headed by gods or devils. Monotheists talked about the king of kings. In every culture we imagined something like our own political system running the Universe. Few found the similarity suspicious. – Carl Sagan

What a marvelous cooperative arrangement – plants and animals each inhaling each other’s exhalations, a kind of planet-wide mutual mouth-to-stoma resuscitation, the entire elegant cycle powered by a star 150 million kilometers away. – Carl Sagan

What an astonishing thing a book is. – Carl Sagan

What an astonishing thing a book is. It’s a flat object made from a tree with flexible parts on which are imprinted lots of funny dark squiggles. But one glance at it and you’re inside the mind of another person, maybe somebody dead for thousands of years. … Books break the shackles of time. A book is proof that humans are capable of working magic – Carl Sagan

What began in deadly competition has helped us to see that global cooperation is the essential precondition for our survival. Travel is broadening. It’s time to hit the road again. – Carl Sagan

What counts is not what sounds plausible, not what we would like to believe, not what one or two witnesses claim, but only what is supported by hard evidence rigorously and skeptically examined. Extraordinary claims require extraordinary evidence. – Carl Sagan

What distinguishes our species is thought. The cerebral cortex is in a way a liberation. We need no longer be trapped in the genetically inherited behavior patterns of lizards and baboons: territoriality and aggression and dominance hierarchies. We are each of us largely responsible for what gets put in to our brains. For what as adults we wind up caring for and knowing about. No longer at the mercy of the reptile brain we can change ourselves. Think of the possibilities. – Carl Sagan

What does it mean for a civilization to be a million years old? We have had radio telescopes and spaceships for a few decades; our technical civilization is a few hundred years old … an advanced civilization millions of years old is as much beyond us as we are beyond a bushbaby or a macaque – Carl Sagan

What is called for is an exquisite balance between two conflicting needs: the most skeptical scrutiny of all hypotheses that are served up to us and at the same time a great openness to new ideas. If you are only skeptical, then no new ideas make it through to you. On the other hand, if you are open to the point of gullibility and have not an ounce of skeptical sense in you, then you cannot distinguish useful ideas from the worthless ones. – Carl Sagan

Whatever the reason you’re on Mars, I’m glad you’re there, and I wish I was with you. – Carl Sagan

What’s the harm of a little mystification? It sure beats boring statistical analyses. – Carl Sagan

When a honeybee dies it releases a death pheromone, a characteristic odour that signals the survivors to remove it from the hive. The corpse is promptly pushed and tugged out of the hive. The death pheromone is oleic acid. What happens if a live bee is dabbed with a drop of oleic acid? Then no matter how strapping and vigourous it might be, it is carried kicking and screaming out of the hive. – Carl Sagan

(When asked merely if they accept evolution, 45 percent of Americans say yes. The figure is 70 percent in China.) When the movie Jurassic Park was shown in Israel, it was condemned by some Orthodox rabbis because it accepted evolution and because it taught that dinosaurs lived a hundred million years ago-when, as is plainly stated at every Rosh Hashanah and every Jewish wedding ceremony, the Universe is less than 6,000 years old. – Carl Sagan

When I was a child I grew up in Brooklyn, New York, and I was a street kid. … [T]here was one aspect of that environment that, for some reason, struck me as different, and that was the stars. … I could tell they were lights in the sky, but that wasn’t an explanation. I mean, what were they? Little electric bulbs on long black wires, so you couldn’t see what they were held up by? What were they? … My mother said to me, “Look, we’ve just got you a library card … get out a book and find the answer.” … It was in there. It was stunning. The answer was that the Sun was a star, except very far away. … The dazzling idea of a universe vast beyond imagining swept over me. … I sensed awe. – Carl Sagan

When Kepler found his long-cherished belief did not agree with the most precise observation, he accepted the uncomfortable fact. He preferred the hard truth to his dearest illusions, that is the heart of science. – Carl Sagan

When permitted to listen to alternative opinions and engage in substantive debate, people have been known to change their minds. It can happen. – Carl Sagan

When we look up at night and view the stars, everything we see is shinning because of distant nuclear fusion. – Carl Sagan

When you buy a used car, you kick the tires, you look at the odometer, you open up the hood. If you do not feel yourself an expert in automobile engines, you bring a friend who is. And you do this with something as unimportant as an automobile. But on the issues of the transcendent, of ethics, of morals, of the origins of the world, of the nature of human beings, on those issues should we not insist upon at least equally skeptical scrutiny? – Carl Sagan

When you realize that no one really knows what they are doing and that everyone is doing the best they can according to their own level of consciousness, life gets a lot easier. Skeptical scrutiny is the means, in both science and religion, by which deep thoughts can be winnowed from deep nonsense. – Carl Sagan

Whenever our ethnic or national prejudices are aroused, in times of scarcity, during challenges to national self esteem or nerve, when we agonize about our diminished cosmic place and purpose, or when fanaticism is bubbling up around us – then, habits of thought familiar from ages past reach for the controls. – Carl Sagan

Where we have strong emotions, we’re liable to fool ourselves. – Carl Sagan

Which aspects of our nature will prevail is uncertain, particularly when our visions and prospects are bound to one small part of the small planet Earth. But up there in the Cosmos an inescapable perspective awaits. – Carl Sagan

While our behavior is still significantly controlled by our genetic inheritance, we have, through our brains, a much richer opportunity to blaze new behavioral and cultural pathways on short timescales. – Carl Sagan

Who are we, if not measured by our impact on others? – Carl Sagan

Who are we, if not measured by our impact on others? That’s who we are! We’re not who we say we are, we’re not who we want to be – we are the sum of the influence and impact that we have, in our lives, on others. – Carl Sagan

Who are we? We find that we live on an insignificant planet of a humdrum star lost between two spiral arms in the outskirts of a galaxy, tucked away in some forgotten corner of a universe in which there are far more galaxies than people. – Carl Sagan

Who are we? We find that we live on an insignificant planet of a humdrum star lost in a galaxy tucked away in some forgotten corner of a universe in which there are far more galaxies than people. – Carl Sagan

Who is more humble? The scientist who looks at the universe with an open mind and accepts whatever the universe has to teach us, or somebody who says everything in this book must be considered the literal truth and never mind the fallibility of all the human beings involved? – Carl Sagan

Who is running the science and technology in a democracy if the people don’t know anything about it? – Carl Sagan

Widespread intellectual and moral docility may be convenient for leaders in the short term, but it is suicidal for nations in the long term. One of the criteria for national leadership should therefore be a talent for understanding, encouraging, and making constructive use of vigorous criticism. – Carl Sagan

Widespread intellectual and moral docility may be convenient for leaders in the short term, but it is suicidal for nations in the long term. One of the criteria for national leadership should therefore be a talent for understanding, encouraging, and making constructive use of vigorous criticism. – Carl Sagan

Wisdom lies in understanding our limitations. – Carl Sagan

With insufficient data it is easy to go wrong. – Carl Sagan

With our critical faculties in decline, unable to distinguish between what feels good and what’s true, we slide, almost without noticing, back into superstition. … We have also arranged things so that almost no one understands science and technology. We might get away with it for a while, but eventually this combustible mixture of ignorance and power is going to blow up in our faces. – Carl Sagan

Writing a novel is like trying to solve a very long mathematical equation. Changing anything can change everything else. – Carl Sagan

Writing is perhaps the greatest of human inventions. – Carl Sagan

You can get into a habit of thought in which you enjoy making fun of all those other people who don’t see things as clearly as you do. We have to guard carefully against it. – Carl Sagan

You can’t convince a believer of anything; for their belief is not based on evidence, it’s based on a deep seated need to believe – Carl Sagan

You could just as well say that an agnostic is a deeply religious person with at least a rudimentary knowledge of human fallibility. – Carl Sagan

You have to know the past to understand the present. – Carl Sagan

You mean am I for it or against it? You think this is a key question I’m going to be asked on Vega, and you want to make sure I give the right answer? Okay. Overpopulation is why I’m in favor of homosexuality and a celibate clergy. A celibate clergy is an especially good idea, because it tends to suppress any hereditary propensity toward fanaticism. – Carl Sagan

‘You mustn’t think of the Universe as a wilderness. It hasn’t been that for billions of years,’ he said. ‘Think of it more as… ..cultivated.’ – Carl Sagan

You’re an interesting species. An interesting mix. You’re capable of such beautiful dreams, and such horrible nightmares. You feel so lost, so cut off, so alone, only you’re not. See, in all our searching, the only thing we’ve found that makes the emptiness bearable, is each other. – Carl Sagan

You’re an interesting species. An interesting mix. You’re capable of such beautiful dreams, and such horrible nightmares. You feel so lost, so cut off, so alone, only you’re not. See, in all our searching, the only thing we’ve found that makes the emptiness bearable, is each other. – Carl Sagan

You’re capable of such beautiful dreams and such horrible nightmares… – Carl Sagan

Carl Sagan Quotes

On Earth

Who will speak for Planet Earth? – Carl Sagan

A new consciousness is developing which sees the earth as a single organism and recognizes that an organism at war with itself is doomed. We are one planet. One of the great revelations of the age of space exploration is the image of the earth finite and lonely, somehow vulnerable, bearing the entire human species through the oceans of space and time. – Carl Sagan

After the earth dies, some 5 billion years from now, after it’s burned to a crisp, or even swallowed by the Sun, there will be other worlds and stars and galaxies coming into being – and they will know nothing of a place once called Earth. – Carl Sagan

Coal, oil and gas are called fossil fuels, because they are mostly made of the fossil remains of beings from long ago. The chemical energy within them is a kind of stored sunlight originally accumulated by ancient plants. Our civilization runs by burning the remains of humble creatures who inhabited the Earth hundreds of millions of years before the first humans came on the scene. Like some ghastly cannibal cult, we subsist on the dead bodies of our ancestors and distant relatives. – Dr. Carl Sagan

If we ruin the earth, there is no place else to go – Carl Sagan

If you look at Earth from space you see a dot, that’s here. That’s home. That’s us. It underscores the responsibility to deal more kindly and compassionately with one another and to preserve and cherish that pale blue dot, the only home we’ve ever known. – Carl Sagan

In fact, the thickness of the Earth’s atmosphere, compared with the size of the Earth, is in about the same ratio as the thickness of a coat of shellac on a schoolroom globe is to the diameter of the globe. That’s the air that nurtures us and almost all other life on Earth, that protects us from deadly ultraviolet light from the sun, that through the greenhouse effect brings the surface temperature above the freezing point. (Without the greenhouse effect, the entire Earth would plunge below the freezing point of water and we’d all be dead.) Now that atmosphere, so thin and fragile, is under assault by our technology. We are pumping all kinds of stuff into it. You know about the concern that chlorofluorocarbons are depleting the ozone layer; and that carbon dioxide and methane and other greenhouse gases are producing global warming, a steady trend amidst fluctuations produced by volcanic eruptions and other sources. Who knows what other challenges we are posing to this vulnerable layer of air that we haven’t been wise enough to foresee? – Carl Sagan

Our loyalties are to the species and the planet. We speak for Earth. Our obligation to survive is owed not just to ourselves but also to that Cosmos, ancient and vast, from which we spring. – Carl Sagan

Our loyalties are to the species and the planet. We speak for Earth. – Carl Sagan

Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves. – Carl Sagan

Some 5 billion years from now, there will be a last perfect day on Earth… then the sun will begin to die, life will be extinguished, the oceans will boil and evaporate away. – Carl Sagan

The boundary between space and the earth is purely arbitrary. And I’ll probably always be interested in this planet – it’s my favorite. – Carl Sagan

The Earth is a place. It is by no means the only place. It is not even a typical place. – Carl Sagan

The Earth is a very small stage in a vast cosmic arena. – Carl Sagan

The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds. – Carl Sagan

The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors, so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds. – Carl Sagan

The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. – Carl Sagan

The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand. It has been said that astronomy is a humbling and character-building experience….. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we’ve ever known. – Carl Sagan

The nature of life on Earth and the search for life elsewhere are two sides of the same question—the search for who we are. – Carl Sagan

The Platonists and their Christian successors held the peculiar notion that the Earth was tainted and somehow nasty, while the heavens were perfect and divine. The fundamental idea that the Earth is a planet, that we are citizens of the Universe, was rejected and forgotten. – Carl Sagan

The surface of the Earth is the shore of the cosmic ocean. From it we have learned most of what we know. Recently, we have waded a little out to sea, enough to dampen our toes or, at most, wet our ankles. The water seems inviting. The ocean calls. – Carl Sagan

We are fortunate: we are alive; we are powerful; the welfare of our civilization and our species is in our hands. If we do not speak for Earth, who will? If we are not committed to our own survival, who will be? – Carl Sagan

We on Earth have just awakened to the great oceans of space and time from which we have emerged. – Carl Sagan

What a splendid perspective contact with a profoundly different civilization might provide! In a cosmic setting vast and old beyond ordinary human understanding we are a little lonely, and we ponder the ultimate significance, if any, of our tiny but exquisite blue planet, the Earth… In the deepest sense the search for extraterrestrial intelligence is a search for ourselves. – Carl Sagan

When you make the finding yourself – even if you’re the last person on Earth to see the light – you’ll never forget it. – Carl Sagan

Wherever possible, scientists experiment. Which experiments suggest themselves often depends on which theories currently prevail. Scientists are intent of testing those theories to the breaking point. They do not trust what is intuitively obvious. That the Earth is flat was once obvious. That heavy bodies fall faster than light ones was once obvious. That bloodsucking leeches cure most diseases was once obvious. That some people are naturally and by divine decree slaves was once obvious. That there is such a place as the center of the Universe, and that the Earth sits in that exalted spot was once obvious. That there is an absolute standard of rest was once obvious. The truth may be puzzling or counterintuitive. It may contradict deeply held beliefs. Experiment is how we get a handle on it. – Carl Sagan

You probably don’t need more weapons than what’s required to destroy every city on earth. There’s only 2,300 cities. So, the United States, by that criteria, only needs 2,300 nuclear weapons – well, we’ve got more than 25,000! – Carl Sagan

Carl Sagan Quotes

On Humanity

A blade of grass is a commonplace on Earth; it would be a miracle on Mars. Our descendants on Mars will know the value of a patch of green. And if a blade of grass is priceless, what is the value of a human being? – Carl Sagan

A single message from space will show that it is possible to live through technological adolescence. . . . It is possible that the future of human civilization depends on the receipt of interstellar messages. – Carl Sagan

A tiny blue dot set in a sunbeam. Here it is. That’s where we live. That’s home. We humans are one species and this is our world. It is our responsibility to cherish it. Of all the worlds in our solar system, the only one so far as we know, graced by life. – Carl Sagan

Accommodation to change, the thoughtful pursuit of alternative futures are keys to the survival of civilization and perhaps of the human species. – Carl Sagan

Across the millennia, the author is speaking, clearly and silently, inside your head, directly to you. Writing is perhaps the greatest of human inventions, binding together people, citizens of distant epochs, who never knew one another. Books break the shackles of time ― proof that humans can work magic. – Carl Sagan

Are we willing to tolerate ignorance and complacency in matters that affect the entire human family? – Carl Sagan

By exploring other worlds we safeguard this one. By itself, I think this fact more than justifies the money our species has spent in sending ships to other worlds. It is our fate to live during one of the most perilous and, at the same time, one of the most hopeful chapters in human history. – Carl Sagan

Eratosthenes was the director of the great library of Alexandria, the Centre of science and learning in the ancient world. Aristotle had argued that humanity was divided into Greeks and everybody else, whom he called barbarians and that the Greeks should keep themselves racially pure. He thought it was fitting for the Greeks to enslave other peoples. But Erathosthenes criticized Aristotle for his blind chauvinism, he believed there was good and bad in every nation. – Carl Sagan

For me, the most ironic token of [the first human moon landing] is the plaque signed by President Richard M. Nixon that Apollo 11 took to the moon. It reads, ‘We came in peace for all Mankind.’ As the United States was dropping seven and a half megatons of conventional explosives on small nations in Southeast Asia, we congratulated ourselves on our humanity. We would harm no one on a lifeless rock. – Carl Sagan

Human beings grew up in forests; we have a natural affinity for them. How lovely a tree is, straining toward the sky. – Carl Sagan

Human beings have a demonstrated talent for self-deception when their emotions are stirred. – Carl Sagan

Human history can be viewed as a slowly dawning awareness that we are members of a larger group. – Carl Sagan

Humans — who enslave, castrate, experiment on, and fillet other animals — have had an understandable penchant for pretending animals do not feel pain. A sharp distinction between humans and ‘animals’ is essential if we are to bend them to our will, make them work for us, wear them, eat them — without any disquieting tinges of guilt or regret. It is unseemly of us, who often behave so unfeelingly toward other animals, to contend that only humans can suffer. The behavior of other animals renders such pretensions specious. They are just too much like us. – Carl Sagan

Humans are very good at dreaming, although you’d never know it from your television. – Carl Sagan

Humans everywhere share the same goals when the context is large enough. And the study of the Cosmos provides the largest possible context … . If a human disagrees with you, let him live. In a hundred billion galaxies, you will not find another … . If we are to survive, our loyalties must be broadened further, to include the whole human community, the entire planet Earth. – Carl Sagan

If we are to survive, our loyalties must be broadened further, to include the whole human community, the entire planet Earth. – Carl Sagan

Philosophers and scientists confidently offer up traits said to be uniquely human, and the monkeys and apes casually knock them down — toppling the pretension that humans constitute some sort of biological aristocracy among the beings on Earth. – Carl Sagan

The understanding of the intent of the artist which I can achieve when high sometimes carries over to when I’m down. This is one of many human frontiers which cannabis has helped me traverse. – Carl Sagan

The uniqueness of humans has been claimed on many grounds, but most often because of our tool-making, culture, language, reason and morality. We have them, the other animals don’t, and — so the argument goes — that’s that. – Carl Sagan

There is today-in a time when old beliefs are withering-a kind of philosophical hunger, a need to know who we are and how we got here. It is an on-going search, often unconscious, for a cosmic perspective for humanity. – Carl Sagan

Those afraid of the universe as it really is, those who pretend to nonexistent knowledge and envision a Cosmos centered on human beings will prefer the fleeting comforts of superstition. – Carl Sagan

We all have a thirst for wonder. It’s a deeply human quality. Science and religion are both bound up with it. What I’m saying is, you don’t have to make stories up, you don’t have to exaggerate. There’s wonder and awe enough in the real world. Nature’s a lot better at inventing wonders than we are. – Carl Sagan

We are privileged to live in, and if we are lucky to influence, one of the most critical epochs in the history of the human species. – Carl Sagan

We are, in a way, temporary ambulatory repositories for our nucleic acids. This does not deny our humanity; it does not prevent us from pursuing the good, the true and the beautiful. But it would be a great mistake to ignore where we have come from in our attempt to determine where we are going. – Carl Sagan

We live in a vast and awesome universe in which, daily, suns are made and worlds destroyed, where humanity clings to an obscure clod of rock. – Carl Sagan

We need to reduce military budgets; raise living standards; engender respect for learning; support science, scholarship, invention, and industry; promote free inquiry; reduce domestic coercion; involve the workers more in managerial decisions; and promote genuine respect and understanding derived from an acknowledgement of our common humanity and our common jeopardy. – Carl Sagan

Writing is perhaps the greatest of human inventions, binding together people who never knew each other, citizens of distant epochs. Books break the shackles of time. A book is proof that humans are capable of magic. – Carl Sagan

On Love

But for us, it’s different. Look again at that dot. That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every superstar,” every supreme leader,” every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam. – Carl Sagan

Every one of us is, in the cosmic perspective, precious . . . In a hundred billion galaxies, you will not find another. – Carl Sagan

For small creatures such as we the vastness is bearable only through love. – Carl Sagan

In the vastness of space and the immensity of time, it is my joy to share a planet and an epoch with Annie. – Carl Sagan

Not explaining science seems to me perverse. When you’re in love, you want to tell the world. – Carl Sagan

Now, another way of looking at this is as a conflict within the human heart, as a conflict between the bureaucratic, hierarchical, aggressive parts of our nature, which in a neurophysiological sense we share with our reptilian ancestors, and the other parts of our nature, the generalized capacity for love, for compassion, for identification with others who may superficially not look or talk or act or dress exactly like us, the ability to figure the world out that is focused and concentrated in our cerebral cortex. Our survival is (how could we have imagined it to be anything else?) a reflection of our own nature and how we manage these contending tendencies within the human heart and mind. – Carl Sagan

Perhaps the depth of love can be calibrated by the number of different selves that are actively involved in a given relationship. – Carl Sagan

The beauty of a living thing is not the atoms that go into it, but the way those atoms are put together. – Carl Sagan

On Life

Life is but a momentary glimpse of the wonder of this astonishing universe, and it is sad to see so many dreaming it away on spiritual fantasy. – Carl Sagan

The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff. – Carl Sagan

The significance of our lives and our fragile planet is then determined only by our own wisdom and courage. We are the custodians of life’s meaning. We long for a Parent to care for us, to forgive us our errors, to save us from our childish mistakes. But knowledge is preferable to ignorance. Better by far to embrace the hard truth than a reassuring fable. If we crave some cosmic purpose, then let us find ourselves a worthy goal. – Carl Sagan

We are made of starstuff. – Carl Sagan

We are one species.
We are starstuff. – Carl Sagan

We are the custodians of life’s meaning. – Carl Sagan

We are…capable of using our compassion and our intelligence, our technology and our wealth, to make an abundant and meaningful life for every inhabitant of this planet. To enhance enormously our understanding of the Universe, and to carry us to the stars. – Carl Sagan

We can’t help it. Life looks for life. – Carl Sagan

We humans look rather different from a tree. Without a doubt we perceive the world differently than a tree does. But down deep, at the molecular heart of life, the trees and we are essentially identical. – Carl Sagan

We hunger to understand, so we invent myths about how we imagine the world is constructed – and they’re, of course, based upon what we know, which is ourselves and other animals. So we make up stories about how the world was hatched from a cosmic egg or created after the mating of cosmic deities or by some fiat of a powerful being. – Carl Sagan

We invest far off places with a certain romance… Long summers, mild winters, rich harvests, plentiful game; none of them lasts for ever. Your own life, or your bands, or even your species – might be owed to a restless few, drawn by a craving they can hardly articulate or understand, to undiscovered lands, and new worlds. – Carl Sagan

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. – Carl Sagan

We make our purpose. – Carl Sagan

When you look more generally at life on Earth, you find that it is all the same kind of life. There are not many different kinds; there’s only one kind. It uses about fifty fundamental biological building blocks, organic molecules. – Carl Sagan

You are worth about 3 dollars worth in chemicals. – Carl Sagan

Carl Sagan Quotes

On Science

Modern science has been a voyage into the unknown, with a lesson in humility waiting at every stop. Many passengers would rather have stayed home. – Carl Sagan

Science … looks skeptically at all claims to knowledge, old and new. It teaches not blind obedience to those in authority but to vigorous debate, and in many respects that’s the secret of its success. – Carl Sagan

Science and mathematics [are] much more compelling and exciting than the doctrines of pseudoscience, whose practitioners – Carl Sagan

Science and mathematics [are] much more compelling and exciting than the doctrines of pseudoscience, whose practitioners were condemned as early as the fifth century B.C. by the Ionian philosopher Heraclitus as night walkers, magicians, priests of Bacchus, priestesses of the wine-vat, mystery-mongers.” But science is more intricate and subtle, reveals a much richer universe, and powerfully evokes our sense of wonder. And it has the additional and important virtue—to whatever extent the word has any meaning—of being true.- Carl Sagan

Science arouses a soaring sense of wonder. But so does pseudoscience. Sparse and poor popularizations of science abandon ecological niches that pseudoscience promptly fills. If it were widely understood that claims to knowledge require adequate evidence before they can be accepted, there would be no room for pseudoscience.- Carl Sagan

Science confers power on anyone who takes the trouble to learn it.- Carl Sagan

Science cuts two ways, of course; its products can be used for both good and evil. But there’s no turning back from science. The early warnings about technological dangers also come from science. – Carl Sagan

Science has itself become a kind of religion. – Carl Sagan

Science is a collaborative enterprise, spanning the generations. When it permits us to see the far side of some new horizon, we remember those who prepared the way – seeing for them also. – Carl Sagan

Science is a way of thinking much more than it is a body of knowledge. Its goal is to find out how the world works, to seek what regularities there may be, to penetrate to the connections of things-from subatomic particles, which may be the constituents of all matter, to living organisms, the human social community, and thence to the cosmos as a whole. – Carl Sagan

Science is a way of thinking much more than it is a body of knowledge.- Carl Sagan

Science is a way of thinking that helps you not to fool yourself. – Carl Sagan

Science is a way to call the bluff of those who only pretend to knowledge. It is a bulwark against mysticism, against superstition, against religion misapplied to where it has no business being. – Carl Sagan

Science is a way to not fool ourselves.- Carl Sagan

Science is an attempt, largely successful, to understand the world, to get a grip on things, to get hold of ourselves, to steer a safe course. Microbiology and meteorology now explain what only a few centuries ago was considered sufficient cause to burn women to death. – Carl Sagan

Science is based on experiment, on a willingness to challenge old dogma, on an openness to see the universe as it really is. Accordingly, science sometimes requires courage – at the very least the courage to question the conventional wisdom. – Carl Sagan

Science is far from a perfect instrument of knowledge. It’s just the best one we have. In this respect, as in many others, it’s like democracy.- Carl Sagan

Science is far from a perfect instrument of knowledge. It’s just the best we have. – Carl Sagan

Science is merely an extremely powerful method of winnowing what’s true from what feels good. – Carl Sagan

Science is more than a body of knowledge. It’s a way of thinking: a way of skeptically interrogating the universe. – Carl Sagan

Science is much more than a body of knowledge. It is a way of thinking. This is central to its success. Science invites us to let the facts in, even when they don’t conform to our preconceptions. It counsels us to carry alternative hypotheses in our heads and see which ones best match the facts. It urges on us a fine balance between no-holds-barred openness to new ideas, however heretical, and the most rigorous skeptical scrutiny of everything – new ideas and established wisdom. – Carl Sagan

Science is not only compatible with spirituality; it is a profound source of spirituality. – Carl Sagan

Science is not only compatible with spirituality; it is a profound source of spirituality. When we recognize our place in an immensity of light-years and in the passage of ages, when we grasp the intricacy, beauty, and subtlety of life, then that soaring feeling, that sense of elation and humility combined, is surely spiritual … The notion that science and spirituality are somehow mutually exclusive does a disservice to both.- Carl Sagan

Science is not perfect. It’s often misused; it’s only a tool, but it’s the best tool we have. Self-correcting , ever changing, applicable to everything: with this tool, we vanquish the impossible. – Carl Sagan

Science is only a Latin word for knowledge. – Carl Sagan

Science is the golden road out of poverty and backwardness for emerging nations. The corollary, one that the United States sometimes fails to grasp, is that abandoning science is the road back into poverty and backwardness.- Carl Sagan

Scientists constantly get clobbered with the idea that we spent 27 billion dollars on the Apollo programs, and are asked What more do you want?” We didn’t spend it; it was done for political reasons. … Apollo was a response to the Bay of Pigs fiasco and to the successful orbital flight of Yuri Gagarin. President Kennedy’s objective was not to find out the origin of the moon by the end of the decade; rather it was to put a man on the moon and bring him back, and we did that.- Carl Sagan

Scientists make mistakes. Accordingly, it is the job of the scientist to recognize our weakness, to examine the widest range of opinions, to be ruthlessly self-critical. Science is a collective enterprise with the error-correction machinery often running smoothly. – Carl Sagan

I am often amazed at how much more capability and enthusiasm for science there is among elementary school youngsters than among college students. – Carl Sagan

I believe that part of what propels science is the thirst for wonder. It’s a very powerful emotion. All children feel it. In a first grade classroom everybody feels it; in a twelfth grade classroom almost nobody feels it, or at least acknowledges it. Something happens between first and twelfth grade, and it’s not just puberty. Not only do the schools and the media not teach much skepticism, there is also little encouragement of this stirring sense of wonder. Science and pseudoscience both arouse that feeling. Poor popularizations of science establish an ecological niche for pseudoscience. – Carl Sagan

I find science so much more fascinating than science fiction. It also has the advantage of being true. – Carl Sagan

I hold that popularization of science is successful if, at first, it does no more than spark the sense of wonder. – Carl Sagan

I know of no area of human endeavor in which science has not had at least one important thing to say. – Carl Sagan

I know that science and technology are not just cornucopias pouring good deeds out into the world. Scientists not only conceived nuclear weapons; they also took political leaders by the lapels, arguing that their nation — whichever it happened to be — had to have one first…. There’s a reason people are nervous about science and technology … the image of the mad scientist haunts our world–from Dr. Faust to Dr. Frankenstein to Dr. Strange love to the white-coated loonies of Saturday morning children’s television. (All this doesn’t inspire budding scientists.) But there’s no way back. We can’t just conclude that science puts too much power into the hands of morally feeble technologists or corrupt, power-crazed politicians and decide to get rid of it. Advances in medicine and agriculture have saved more lives than have been lost in all the wars in history. Advances in transportation, communication, and entertainment have transformed the world. The sword of science is double-edged. Rather, its awesome power forces on all of us, including politicians, a new responsibility — more attention to the long-term consequences of technology, a global and transgenerational perspective, an incentive to avoid easy appeals to nationalism and chauvinism. Mistakes are becoming too expensive. – Carl Sagan

I maintain there is much more wonder in science than in pseudoscience. And in addition, to whatever measure this term has any meaning, science has the additional virtue, and it is not an inconsiderable one, of being true. – Carl Sagan

I worry that, especially as the Millennium edges nearer, pseudo-science and superstition will seem year by year more tempting, the siren song of unreason more sonorous and attractive. – Carl Sagan

In science it often happens that scientists say, ‘You know that’s a really good argument; my position is mistaken,’ and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn’t happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion. – Carl Sagan

It is the tension between creativity and skepticism that has produced the stunning and unexpected findings of science. – Carl Sagan

Skeptical scrutiny is the means, in both science and religion, by which deep thoughts can be winnowed from deep nonsense. – Carl Sagan

The method of science is tried and true. It is not perfect, it’s just the best we have. And to abandon it, with its skeptical protocols, is the pathway to a dark age. – Carl Sagan

The method of science, as stodgy and grumpy as it may seem, is far more important than the findings of science. – Carl Sagan

The success of science, both its intellectual excitement and its practical application, depend upon the self-correcting character of science. There must be a way of testing any valid idea. It must be possible to reproduce any valid experiment. The character or beliefs of the scientists are irrelevant; all that matters is whether the evidence supports his contention. – Carl Sagan

The suppression of uncomfortable ideas may be common in religion or in politics, but it is not the path to knowledge, and there’s no place for it in the endeavor of science. We do not know beforehand where fundamental insights will arise from about our mysterious and lovely solar system. The history of our study of our solar system shows us clearly that accepted and conventional ideas are often wrong, and that fundamental insights can arise from the most unexpected sources. – Carl Sagan

The suppression of uncomfortable ideas may be common in religion or in politics, but it is not the path to knowledge; it has no in the endeavor of science. We do not know in advance who will discover fundamental insights. – Carl Sagan

The values of science and the values of democracy are concordant, in many cases indistinguishable. Science and democracy began – in their civilized incarnations – in the same time and place, Greece in the seventh and sixth centuries B.C. . . . Science thrives on, indeed requires, the free exchange of ideas; its values are antithetical to secrecy. Science holds to no special vantage points or privileged positions. Both science and democracy encourage unconventional opinions and vigorous debate. Both demand adequate reason, coherent argument, rigorous standards of evidence and honesty. – Carl Sagan

There are many hypotheses in science that are wrong. That’s perfectly alright; it’s the aperture to finding out what’s right. Science is a self-correcting process. To be accepted, new ideas must survive the most rigorous standards of evidence and scrutiny. – Carl Sagan

We have also arranged things so that almost no one understands science and technology. This is a prescription for disaster. We might get away with it for a while, but sooner or later this combustible mixture of ignorance and power is going to blow up in our faces. – Carl Sagan

We’ve arranged a civilization in which most crucial elements profoundly depend on science and technology. We have also arranged things so that almost no one understands science and technology. This is a prescription for disaster. We might get away with it for a while, but sooner or later this combustible mixture of ignorance and power is going to blow up in our faces. – Carl Sagan

Carl Sagan Quotes

On God

Your god is too small for my universe. – Carl Sagan

A general problem with much of Western theology in my view is that the god portrayed is too small. It is a god of a tiny world and not a god of a galaxy much less of a universe. – Carl Sagan

An atheist has to know more than I know. An atheist is someone who knows there is no God. – Carl Sagan

An atheist is someone who is certain that God does not exist, someone who has compelling evidence against the existence of God. I know of no such compelling evidence. Because God can be relegated to remote times and places and to ultimate causes, we would have to know a great deal more about the universe than we do now to be sure that no such God exists. To be certain of the existence of God and to be certain of the nonexistence of God seem to me to be the confident extremes in a subject so riddled with doubt and uncertainty as to inspire very little confidence indeed. – Carl Sagan

Anything you don’t understand, Mr. Rankin, you attribute to God. God for you is where you sweep away all the mysteries of the world, all the challenges to our intelligence. You simply turn your mind off and say God did it. – Carl Sagan, [Dr. Arroway in Carl Sagan’s Contact (New York: Pocket Books, 1985), p. 166.]

At the extremes it is difficult to distinguish pseudoscience from rigid, doctrinaire religion. – Carl Sagan, [Carl Sagan, On God]

If God is omnipotent and omniscient, why didn’t he start the universe out in the first place so it would come out the way he wants? Why’s he constantly repairing and complaining? No, there’s one thing the Bible makes clear: The biblical God is a sloppy manufacturer. He’s not good at design, he’s not good at execution. He’d be out of business, if there was any competition. – Carl Sagan

In many cultures it is customary to answer that God created the universe out of nothing. But this is mere temporizing. If we wish courageously to pursue the question, we must, of course ask next where God comes from? And if we decide this to be unanswerable, why not save a step and conclude that the universe has always existed? – Carl Sagan, [Carl Sagan, Cosmos, p. 257]

In some respects, science has far surpassed religion in delivering awe. How is it that hardly any major religion has looked at science and concluded, This is better than we thought! The Universe is much bigger than our prophets said, grander, more subtle, more elegant. God must be even greater than we dreamed”? Instead they say, ‘No, no, no! My god is a little god, and I want him to stay that way.’ – Carl Sagan

Many statements about God are confidently made by theologians on grounds that today at least sound specious. Thomas Aquinas claimed to prove that God cannot make another God, or commit suicide, or make a man without a soul, or even make a triangle whose interior angles do not equal 180 degrees. But Bolyai and Lobachevsky were able to accomplish this last feat (on a curved surface) in the 19th century, and they were not even approximately gods. – Carl Sagan, [Carl Sagan, Scripture

My deeply held belief is that if a god of anything like the traditional sort exists, our curiosity and intelligence were provided by such a god…on the other hand if such a god does not exist then our curiosity and intelligence are the essential tools for survival. In either case the enterprise of knowledge is essential for the welfare of the human species. – Carl Sagan

The fact is that far more crime and child abuse has been committed by zealots in the name of God, Jesus and Mohammed than has ever been committed in the name of Satan. Many people don’t like that statement, but few can argue with it. – Carl Sagan

The idea that God is an oversized white male with a flowing beard who sits in the sky and tallies the fall of every sparrow is ludicrous. But if by God one means the set of physical laws that govern the universe, then clearly there is such a God. This God is emotionally unsatisfying… it does not make much sense to pray to the law of gravity. – Carl Sagan

Those who raise questions about the God hypothesis and the soul hypothesis are by no means all atheists. An atheist is someone who is certain that God does not exist, someone who has compelling evidence against the existence of God. I know of no such compelling evidence. Because God can be relegated to remote times and places and to ultimate causes, we would have to know a great deal more about the universe than we do to be sure that no such God exists. To be certain of the existence of God and to be certain of the nonexistence of God seem to me to be the confident extremes in a subject so riddled with doubt and uncertainty as to inspire very little confidence indeed. – Carl Sagan, Conversations with Carl Sagan (2006), edited by Tom Head, p. 70

What I’m saying is, if God wanted to send us a message, and ancient writings were the only way he could think of doing it, he could have done a better job. – Carl Sagan, [Dr. Arroway in Carl Sagan’s Contact (New York: Pocket Books, 1985), p. 164.]

Where did God come from? If we decide this is an unanswerable question why not save a step and conclude that the origin of the universe is an unanswerable question. – Carl Sagan

You see, the religious people — most of them — really think this planet is an experiment. That’s what their beliefs come down to. Some god or other is always fixing and poking, messing around with tradesmen’s wives, giving tablets on mountains, commanding you to mutilate your children, telling people what words they can say and what words they can’t say, making people feel guilty about enjoying themselves, and like that. Why can’t the gods leave well enough alone? All this intervention speaks of incompetence. If God didn’t want Lot’s wife to look back, why didn’t he make her obedient, so she’d do what her husband told her? Or if he hadn’t made Lot such a s–thead, maybe she would’ve listened to him more. If God is omnipotent and omniscient, why didn’t he start the universe out in the first place so it would come out the way he wants? Why’s he constantly repairing and complaining? No, there’s one thing the Bible makes clear: The biblical God is a sloppy manufacturer. He’s not good at design; he’s not good at execution. He’d be out of business if there was any competition. – Carl Sagan, [Sol Hadden in Carl Sagan’s Contact (New York: Pocket Books, 1985), p. 285.]

On Faith

All of us cherish our beliefs. They are, to a degree, self-defining. When someone comes along who challenges our belief system as insufficiently well-based – or who, like Socrates, merely asks embarrassing questions that we haven’t thought of, or demonstrates that we’ve swept key underlying assumptions under the rug – it becomes much more than a search for knowledge. It feels like a personal assault. – Carl Sagan

Any faith that admires truth, that strives to know God, must be brave enough to accommodate the universe. – Carl Sagan

Atheism is more than just the knowledge that gods do not exist, and that religion is either a mistake or a fraud. Atheism is an attitude, a frame of mind that looks at the world objectively, fearlessly, always trying to understand all things as a part of nature. – Carl Sagan

Atheism is very stupid. – Carl Sagan

Faith is clearly not enough for many people. They crave hard evidence, scientific proof. They long for the scientific seal of approval, but are unwilling to put up with the rigorous standards of evidence that impart credibility to that seal. – Carl Sagan

I don’t want to believe. I want to know. – Carl Sagan

I would suggest that science is, at least in my part, informed worship. – Carl Sagan

Indeed the reasoned criticism of a prevailing belief is a service to the proponents of that belief; if they are incapable of defending it, they are well advised to abandon it. This self-questioning and error-correcting aspect of the scientific method is its most striking property. – Carl Sagan

It is said that men may not be the dreams of the god, but rather that the gods are the dreams of men. – Carl Sagan

My deeply held belief is that if a god of anything like the traditional sort exists, our curiosity and intelligence are provided by such a god. We would be unappreciative of those gifts (as well as unable to take such a course of action) if we suppressed our passion to explore the universe and ourselves. On the other hand, if such a traditional god does not exist, our curiosity and our intelligence are the essential tools for managing our survival. In either case, the enterprise of knowledge is consistent with both science and religion, and is essential for the welfare of the human species. – Carl Sagan

My faith is strong I don’t need proofs, but every time a new fact comes along it simply confirms my faith. – Carl Sagan, [Palmer Joss in Carl Sagan’s Contact (New York: Pocket Books, 1985), p. 172.]

Skepticism enables us to distinguish fancy from fact, to test our speculations. – Carl Sagan

On Religion

Religions are often state-protected nurseries of pseudoscience, although there’s no reason why religions have to play that role. In a way, it’s an artifact from times long gone. – Carl Sagan

Religions are tough. Either they make no contentions which are subject to disproof or they quickly redesign doctrine after disproof. … near the core of the religious experience is something remarkably resistant to rational inquiry. – Carl Sagan

Religions contradict one another-on small matters, such as whether we should put on a hat or take one off on entering a house of worship, or whether we should eat beef and eschew pork or the other way around, all the way to the most central issues, such as whether there are no gods, one God, or many gods. – Carl Sagan

A celibate clergy is an especially good idea, because it tends to suppress any hereditary propensity toward fanaticism. – Carl Sagan

A religion, old or new, that stressed the magnificence of the universe as revealed by modern science might be able to draw forth reserves of reverence and awe hardly tapped by conventional faiths. Sooner or later such a religion will emerge. – Carl Sagan

Charlie Holloway (human): “What we hoped to achieve was to meet our makers. To get answers. Why they even made us in the first place.”
David (AI robot): “Why do you think your people made me?”
Charlie Holloway (human): “We made you because we could.”
David (AI robot): “Can you imagine how disappointing it would be for you to hear the same thing from your creator?”
Charlie Holloway (human): “I guess it’s good you can’t be disappointed.” – Carl Sagan

Has there ever been a religion with the prophetic accuracy and reliability of science? . . . No other human institution comes close. – Carl Sagan

How is it that hardly any major religion has looked at science and concluded, ‘This is better than we thought! The Universe is much bigger than our prophets said, grander, more subtle, more elegant?’ Instead they say, ‘No, no, no! My god is a little god, and I want him to stay that way.’ A religion, old or new, that stressed the magnificence of the Universe as revealed by modern science might be able to draw forth reserves of reverence and awe hardly tapped by the conventional faiths. – Carl Sagan

In science it often happens that scientists say, ‘You know that’s a really good argument; my position is mistaken,’ and then they actually change their minds and you never hear that old view from them again. They really do it. It doesn’t happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion. – Carl Sagan, [1987 CSICOP keynote address]

My long-time view about Christianity is that it represents an amalgam of two seemingly immiscible parts-the religion of Jesus and the religion of Paul. Thomas Jefferson attempted to excise the Pauline parts of the New Testament. There wasn’t much left when he was done, but it was an inspiring document. – Carl Sagan

Since World War II, Japan has spawned enormous numbers of new religions featuring the supernatural…. In Thailand, diseases are treated with pills manufactured from pulverized sacred Scripture. Witches are today being burned in South Africa…. The worldwide TM [Transcendental Meditation] organization has an estimated valuation of $3 billion. For a fee, they promise to make you invisible, to enable you to fly. – Carl Sagan

Skeptical scrutiny is the means, in both science and religion, by which deep insights can be winnowed from deep nonsense. – Carl Sagan

The Bill of Rights decoupled religion from the state, in part because so many religions were steeped in an absolutist frame of mind – each convinced that it alone had a monopoly on the truth and therefore eager for the state to impose this truth on others. – Carl Sagan

The Hindu religion is the only of the World’s great faiths dedicated to the idea that the Cosmos itself undergoes an immense, indeed an infinite, number of deaths and rebirths. – Carl Sagan

The Hindu religion is the only one of the world’s great faiths dedicated to the idea that the Cosmos itself undergoes an immense, indeed an infinite, number of deaths and rebirths. It is the only religion in which the time scales correspond to those of modern scientific cosmology. Its cycles run from our ordinary day and night to a day and night of Brahma, 8.64 billion years long. Longer than the age of the Earth or the Sun and about half the time since the Big Bang. – Carl Sagan

The major religions on the Earth contradict each other left and right. You can’t all be correct. And what if all of you are wrong? It’s a possibility, you know. You must care about the truth, right? Well, the way to winnow through all the differing contentions is to be skeptical. I’m not any more skeptical about your religious beliefs than I am about every new scientific idea I hear about. But in my line of work, they’re called hypotheses, not inspiration and not revelation. – Carl Sagan, [Dr. Arroway in Carl Sagan’s Contact (New York: Pocket Books, 1985), p. 162. ]

They (i. e., the Pythagoreans ) did not advocate the free confrontation of conflicting points of view. Instead, like all orthodox religions, they practised a rigidity that prevented them from correcting their errors. – Carl Sagan

You can’t convince a believer of anything; for their belief is not based on evidence, it’s based on a deep seated need to believe.” – Carl Sagan, [Dr. Arroway in Carl Sagan’s Contact (New York: Pocket Books, 1985]

Your religion assumes that people are children and need a boogeyman so they’ll behave. You want people to believe in God so they’ll obey the law. That’s the only means that occurs to you: a strict secular police force, and the threat of punishment by an all-seeing God for whatever the police overlook. You sell human beings short. – Carl Sagan

On Afterlife

I would love to believe that when I die I will live again, that some thinking, feeling, remembering part of me will continue. But much as I want to believe that, and despite the ancient and worldwide cultural traditions that assert an afterlife, I know of nothing to suggest that it is more than wishful thinking.
The world is so exquisite with so much love and moral depth, that there is no reason to deceive ourselves with pretty stories for which there’s little good evidence. Far better it seems to me, in our vulnerability, is to look death in the eye and to be grateful every day for the brief but magnificent opportunity that life provides. – Carl Sagan“In the Valley of the Shadow”, Parade, 10 March 1996

If some good evidence for life after death were announced, I’d be eager to examine it; but it would have to be real scientific data, not mere anecdote. As with the face on Mars and alien abductions, better the hard truth, I say, than the comforting fantasy. – Carl Sagan [Reason and Religion]

Personally, I would be delighted if there were a life after death, especially if it permitted me to continue to learn about this world and others, if it gave me a chance to discover how history turns out. – Carl Sagan

One prominent In a democracy, opinions that upset everyone are sometimes exactly what we need. We should be teaching our children the scientific method and the Bill of Rights. – Carl Sagan [Carl Sagan & Ann Druyan]

Think of how many religions attempt to validate themselves with prophecy. Think of how many people rely on these prophecies, however vague, however unfulfilled, to support or prop up their beliefs. Yet has there ever been a religion with the prophetic accuracy and reliability of science? … No other human institution comes close. – Carl Sagan, Ch. 2 : Science and Hope, p. 30

The idea of a spiritual part of our nature that survives death, the notion of an afterlife, ought to be easy for religions and nations to sell. This is not an issue of which we might anticipate widespread skepticism. People will want to believe it, even if the evidence is meager to nil… compelling testimony … provides that our personality, character, memory … resides in the matter of the brain, it is easy not to focus on it, to find ways to evade the weight of the evidence. – Carl Sagan

Carl Sagan Quotes

From Wikiquote

  • There is a place with four suns in the sky — red, white, blue, and yellow; two of them are so close together that they touch, and star-stuff flows between them. I know of a world with a million moons. I know of a sun the size of the Earth — and made of diamond. There are atomic nuclei a few miles across which rotate thirty times a second. There are tiny grains between the stars, with the size and atomic composition of bacteria. There are stars leaving the Milky Way, and immense gas clouds falling into it. There are turbulent plasmas writhing with X- and gamma-rays and mighty stellar explosions. There are, perhaps, places which are outside our universe. The universe is vast and awesome, and for the first time we are becoming a part of it.
    • Planetary Exploration (University of Oregon Books, Eugene, Oregon, 1970), page 15
  • It is easy to create an interstellar radio message which can be recognized as emanating unambiguously from intelligent beings. A modulated signal (‘beep,’ ‘beep-beep,’ . . . ) comprising the numbers 1, 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, for example, consists exclusively of the first 12 prime numbers—that is, numbers that can be divided only by 1, or by themselves. A signal of this kind, based on a simple mathematical concept, could only have a biological origin. . . . But by far the most promising method is to send pictures.
    • Smithsonian magazine, May 1978, pp. 43, 44. Quoted in Awake! magazine, 1978, 8/22.
  • Imagine, a room, awash in gasoline. And there are two implacable enemies in that room. One of them has 9,000 matches. The other has 7,000 matches. Each of them is concerned about who’s ahead, who’s stronger. Well, that’s the kind of situation we are actually in. The amount of weapons that are available to the United States and the Soviet Union are so bloated, so grossly in excess of what’s needed to dissuade the other that if it weren’t so tragic, it would be laughable.
    • Remarks on the nuclear arms race, on ABC News Viewpoint — “The Day After” (20 November 1983)
  • It seems to me what is called for is an exquisite balance between two conflicting needs: the most skeptical scrutiny of all hypotheses that are served up to us and at the same time a great openness to new ideas … If you are only skeptical, then no new ideas make it through to you … On the other hand, if you are open to the point of gullibility and have not an ounce of skeptical sense in you, then you cannot distinguish the useful ideas from the worthless ones.
    • “The Burden of Skepticism” in Skeptical Inquirer Vol. 12, Issue 1 (Fall 1987)
  • In science it often happens that scientists say, “You know that’s a really good argument; my position is mistaken,” and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn’t happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion.
    • Keynote address at CSICOP conference (1987), as quoted in Do Science and the Bible Conflict? (2003) by Judson Poling, p. 30
  • We live in a society absolutely dependent on science and technology and yet have cleverly arranged things so that almost no one understands science and technology. That’s a clear prescription for disaster.
    • Bringing Science Down to Earth (1994), co-authored with Anne Kalosh, in Hemispheres (October 1994), p. 99; this is similar to statements either mentioned in earlier interviews or published later in the book The Demon-Haunted World : Science as a Candle in the Dark (1995)
    • Variants:
    • We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology.
      • “Why We Need To Understand Science” in The Skeptical Inquirer Vol. 14, Issue 3 (Spring 1990)
    • Not explaining science seems to me perverse. When you’re in love, you want to tell the world.
      • “With Science on Our Side”, Washington Post (9 January 1994)
    • We’ve arranged a society based on science and technology, in which nobody understands anything about science and technology. And this combustible mixture of ignorance and power, sooner or later, is going to blow up in our faces. Who is running the science and technology in a democracy if the people don’t know anything about it?
      • Charlie Rose: An Interview with Carl Sagan, May 27, 1996.
    • I know that science and technology are not just cornucopias pouring good deeds out into the world. Scientists not only conceived nuclear weapons; they also took political leaders by the lapels, arguing that their nation — whichever it happened to be — had to have one first. … There’s a reason people are nervous about science and technology.
      And so the image of the mad scientist haunts our world—from Dr. Faust to Dr. Frankenstein to Dr. Strangelove to the white-coated loonies of Saturday morning children’s television. (All this doesn’t inspire budding scientists.) But there’s no way back. We can’t just conclude that science puts too much power into the hands of morally feeble technologists or corrupt, power-crazed politicians and decide to get rid of it. Advances in medicine and agriculture have saved more lives than have been lost in all the wars in history. Advances in transportation, communication, and entertainment have transformed the world. The sword of science is double-edged. Rather, its awesome power forces on all of us, including politicians, a new responsibility — more attention to the long-term consequences of technology, a global and transgenerational perspective, an incentive to avoid easy appeals to nationalism and chauvinism. Mistakes are becoming too expensive.

      • “Why We Need To Understand Science” in The Skeptical Inquirer Vol. 14, Issue 3 (Spring 1990)
    • Science is much more than a body of knowledge. It is a way of thinking. This is central to its success. Science invites us to let the facts in, even when they don’t conform to our preconceptions. It counsels us to carry alternative hypotheses in our heads and see which ones best match the facts. It urges on us a fine balance between no-holds-barred openness to new ideas, however heretical, and the most rigorous skeptical scrutiny of everything — new ideas and established wisdom. We need wide appreciation of this kind of thinking. It works. It’s an essential tool for a democracy in an age of change. Our task is not just to train more scientists but also to deepen public understanding of science.
      • “Why We Need To Understand Science” in The Skeptical Inquirer Vol. 14, Issue 3 (Spring 1990)
    • Science is […] a way of skeptically interrogating the universe with a fine understanding of human fallibility. If we are not able to ask skeptical questions, to interrogate those who tell us that something is true, to be skeptical of those in authority, then we’re up for grabs for the next charlatan, political or religious, who comes ambling along.
      • Charlie Rose: An Interview with Carl Sagan (27 May 1996)
  • The idea that God is an oversized white male with a flowing beard who sits in the sky and tallies the fall of every sparrow is ludicrous. But if by God one means the set of physical laws that govern the universe, then clearly there is such a God. This God is emotionally unsatisfying… it does not make much sense to pray to the law of gravity.
    • As quoted in “Scientists & Their Gods” in U.S. News & World Report Vol. 111 (1991)
  • Humans — who enslave, castrate, experiment on, and fillet other animals — have had an understandable penchant for pretending animals do not feel pain. A sharp distinction between humans and ‘animals’ is essential if we are to bend them to our will, make them work for us, wear them, eat them — without any disquieting tinges of guilt or regret. It is unseemly of us, who often behave so unfeelingly toward other animals, to contend that only humans can suffer. The behavior of other animals renders such pretensions specious. They are just too much like us.
    • “Shadows of Forgotten Ancestors” (1992) (co-written with Ann Druyan)
  • In fact, the thickness of the Earth’s atmosphere, compared with the size of the Earth, is in about the same ratio as the thickness of a coat of shellac on a schoolroom globe is to the diameter of the globe. That’s the air that nurtures us and almost all other life on Earth, that protects us from deadly ultraviolet light from the sun, that through the greenhouse effect brings the surface temperature above the freezing point. (Without the greenhouse effect, the entire Earth would plunge below the freezing point of water and we’d all be dead.) Now that atmosphere, so thin and fragile, is under assault by our technology. We are pumping all kinds of stuff into it. You know about the concern that chlorofluorocarbons are depleting the ozone layer; and that carbon dioxide and methane and other greenhouse gases are producing global warming, a steady trend amidst fluctuations produced by volcanic eruptions and other sources. Who knows what other challenges we are posing to this vulnerable layer of air that we haven’t been wise enough to foresee?
    • In Wonder and Skepticism, Skeptical Enquirer (Jan-Feb 1995), 19, No. 1.
  • The truth may be puzzling. It may take some work to grapple with. It may be counterintuitive. It may contradict deeply held prejudices. It may not be consonant with what we desperately want to be true. But our preferences do not determine what’s true. We have a method, and that method helps us to reach not absolute truth, only asymptotic approaches to the truth — never there, just closer and closer, always finding vast new oceans of undiscovered possibilities. Cleverly designed experiments are the key.
    • “Wonder and Skepticism”, Skeptical Inquirer19 (1), January-February 1995, ISSN0194-6730
  • If you take a look at science in its everyday function, of course you find that scientists run the gamut of human emotions and personalities and character and so on. But there’s one thing that is really striking to the outsider, and that is the gauntlet of criticism that is considered acceptable or even desirable. The poor graduate student at his or her Ph.D. oral exam is subjected to a withering crossfire of questions that sometimes seem hostile or contemptuous; this from the professors who have the candidate’s future in their grasp. The students naturally are nervous; who wouldn’t be? True, they’ve prepared for it for years. But they understand that at that critical moment they really have to be able to answer questions. So in preparing to defend their theses, they must anticipate questions; they have to think, “Where in my thesis is there a weakness that someone else might find — because I sure better find it before they do, because if they find it and I’m not prepared, I’m in deep trouble.”
    • “Wonder and Skepticism”, Skeptical Inquirer19 (1), January-February 1995, ISSN0194-6730
  • Every kid starts out as a natural-born scientist, and then we beat it out of them. A few trickle through the system with their wonder and enthusiasm for science intact.
    • PT Staff (01 January 1996), “Carl Sagan, author interview”, Psychology Today
  • Something dreadful happens to students between first and twelfth grades, and it’s not just puberty.
    • Carl Sagan: ‘Science Is a Way of Thinking’, Science Friday interview from May 1996, 27 December 2013
  • That kind of skeptical, questioning, “don’t accept what authority tells you” attitude of science — is also nearly identical to the attitude of mind necessary for a functioning democracy. Science and democracy have very consonant values and approaches, and I don’t think you can have one without the other.
    • Talk of the Nation (3 May 1996)
  • Who is more humble? The scientist who looks at the universe with an open mind and accepts whatever it has to teach us, or somebody who says everything in this book must be considered the literal truth and never mind the fallibility of all the human beings involved?
    • Charlie Rose: An Interview with Carl Sagan, May 27, 1996.
  • All of the books in the world contain no more information than is broadcast as video in a single large American city in a single year. Not all bits have equal value.
    • Carl Sagan (July 2011), Cosmos (2011 ebook edition), Random House;
  • I think people in power have a vested interest to oppose critical thinking.
    • Carl Sagan: ‘Science Is a Way of Thinking’, Science Friday interview from May 1996, 27 December 2013

Essay as “Mr. X” (1969)

  • I had become friendly with a group of people who occasionally smoked cannabis, irregularly, but with evident pleasure. Initially I was unwilling to partake, but the apparent euphoria that cannabis produced and the fact that there was no physiological addiction to the plant eventually persuaded me to try. My initial experiences were entirely disappointing; there was no effect at all, and I began to entertain a variety of hypotheses about cannabis being a placebo which worked by expectation and hyperventilation rather than by chemistry. After about five or six unsuccessful attempts, however, it happened.
  • There’s a part of me making, creating the perceptions which in everyday life would be bizarre; there’s another part of me which is a kind of observer. About half of the pleasure comes from the observer-part appreciating the work of the creator-part. I smile, or sometimes even laugh out loud at the pictures on the insides of my eyelids. In this sense, I suppose cannabis is psychotomimetic, but I find none of the panic or terror that accompanies some psychoses. Possibly this is because I know it’s my own trip, and that I can come down rapidly any time I want to.
  • The cannabis experience has greatly improved my appreciation for art, a subject which I had never much appreciated before. The understanding of the intent of the artist which I can achieve when high sometimes carries over to when I’m down. This is one of many human frontiers which cannabis has helped me traverse. There also have been some art-related insights — I don’t know whether they are true or false, but they were fun to formulate.
  • Cannabis also enhances the enjoyment of sex — on the one hand it gives an exquisite sensitivity, but on the other hand it postpones orgasm: in part by distracting me with the profusion of image passing before my eyes. The actual duration of orgasm seems to lengthen greatly, but this may be the usual experience of time expansion which comes with cannabis smoking.
  • I do not consider myself a religious person in the usual sense, but there is a religious aspect to some highs. The heightened sensitivity in all areas gives me a feeling of communion with my surroundings, both animate and inanimate. Sometimes a kind of existential perception of the absurd comes over me and I see with awful certainty the hypocrisies and posturing of myself and my fellow men. And at other times, there is a different sense of the absurd, a playful and whimsical awareness. Both of these senses of the absurd can be communicated, and some of the most rewarding highs I’ve had have been in sharing talk and perceptions and humor. Cannabis brings us an awareness that we spend a lifetime being trained to overlook and forget and put out of our minds. A sense of what the world is really like can be maddening; cannabis has brought me some feelings for what it is like to be crazy, and how we use that word “crazy” to avoid thinking about things that are too painful for us. In the Soviet Union political dissidents are routinely placed in insane asylums. The same kind of thing, a little more subtle perhaps, occurs here: “did you hear what Lenny Bruce said yesterday? He must be crazy.”
  • When I’m high I can penetrate into the past, recall childhood memories, friends, relatives, playthings, streets, smells, sounds, and tastes from a vanished era. I can reconstruct the actual occurrences in childhood events only half understood at the time. Many but not all my cannabis trips have somewhere in them a symbolism significant to me which I won’t attempt to describe here, a kind of mandala embossed on the high. Free-associating to this mandala, both visually and as plays on words, has produced a very rich array of insights.
    There is a myth about such highs: the user has an illusion of great insight, but it does not survive scrutiny in the morning. I am convinced that this is an error, and that the devastating insights achieved when high are real insights; the main problem is putting these insights in a form acceptable to the quite different self that we are when we’re down the next day.
  • Incidentally, I find that reasonably good insights can be remembered the next day, but only if some effort has been made to set them down another way. If I write the insight down or tell it to someone, then I can remember it with no assistance the following morning; but if I merely say to myself that I must make an effort to remember, I never do.
    I find that most of the insights I achieve when high are into social issues, an area of creative scholarship very different from the one I am generally known for.
  • I can remember the night that I suddenly realized what it was like to be crazy, or nights when my feelings and perceptions were of a religious nature. I had a very accurate sense that these feelings and perceptions, written down casually, would not stand the usual critical scrutiny that is my stock in trade as a scientist. If I find in the morning a message from myself the night before informing me that there is a world around us which we barely sense, or that we can become one with the universe, or even that certain politicians are desperately frightened men, I may tend to disbelieve; but when I’m high I know about this disbelief. And so I have a tape in which I exhort myself to take such remarks seriously. I say “Listen closely, you sonofabitch of the morning! This stuff is real!” I try to show that my mind is working clearly; I recall the name of a high school acquaintance I have not thought of in thirty years; I describe the color, typography, and format of a book in another room and these memories do pass critical scrutiny in the morning. I am convinced that there are genuine and valid levels of perception available with cannabis (and probably with other drugs) which are, through the defects of our society and our educational system, unavailable to us without such drugs. Such a remark applies not only to self-awareness and to intellectual pursuits, but also to perceptions of real people, a vastly enhanced sensitivity to facial expression, intonations, and choice of words which sometimes yields a rapport so close it’s as if two people are reading each other’s minds.
  • My high is always reflective, peaceable, intellectually exciting, and sociable, unlike most alcohol highs, and there is never a hangover. Through the years I find that slightly smaller amounts of cannabis suffice to produce the same degree of high, and in one movie theater recently I found I could get high just by inhaling the cannabis smoke which permeated the theater.
    There is a very nice self-titering aspect to cannabis. Each puff is a very small dose; the time lag between inhaling a puff and sensing its effect is small; and there is no desire for more after the high is there.
  • I think the ratio, R, of the time to sense the dose taken to the time required to take an excessive dose is an important quantity. R is very large for LSD (which I’ve never taken) and reasonably short for cannabis. Small values of R should be one measure of the safety of psychedelic drugs. When cannabis is legalized, I hope to see this ratio as one of the parameters printed on the pack. I hope that time isn’t too distant; the illegality of cannabis is outrageous, an impediment to full utilization of a drug which helps produce the serenity and insight, sensitivity and fellowship so desperately needed in this increasingly mad and dangerous world.

The Dragons of Eden (1977)

All page numbers are from the mass market paperback edition published by Ballantine Books ISBN 0-345-29765-2 (12th U.S. printing, March 1983)
  • I proffer the following ideas with a substantial degree of trepidation; I know very well that many of them are speculative and can be proved or disproved on the anvil of experiment. Introduction (p. 5)
  • My fundamental premise about the brain is that its workings—what we sometimes call “mind”—are a consequence of its anatomy and physiology, and nothing more. Introduction (p. 7)
  • Absence of evidence is not evidence of absence. Introduction (p. 7)
  • The entire recent history of biology shows that we are, to a remarkable degree, the results of the interactions of an extremely complex array of molecules; and the aspect of biology that was once considered its holy of holies, the nature of the genetic material, has now been fundamentally understood in terms of the chemistry of its constituent nucleic acids, DNA and RNA, and their operational agents, the proteins. Introduction (p. 7)
  • Those at too great a distance may, I am well aware, mistake ignorance for perspective. Introduction (p. 7)
  • At any rate, both because of the clear trend in the recent history of biology and because there is not a shred of evidence to support it, I will not in these pages entertain any hypotheses on what used to be called the mind-body dualism, the idea that inhabiting the matter of the body is something made of quite different stuff, called mind. Introduction (p. 7)
  • It is important to distinguish between the amount of information and the quality of that information. Chapter 2, “Genes and Brains” (p. 21)
  • A mutation in a DNA molecule within a chromosome of a skin cell in my index finger has no influence on heredity. Fingers are not involved, at least directly, in the propagation of the species. Chapter 2, “Genes and Brains” (p. 27)
  • Note that in all this interaction between mutation and natural selection, no moth is making a conscious effort to adapt to a changed environment. The process is random and statistical. Chapter 2, “Genes and Brains” (p. 28)
  • There is a popular contention that half or more of the brain is unused. From an evolutionary point of view this would be quite extraordinary: why should it have evolved if it had no function? But actually the statement is made on very little evidence. 
    • Chapter 2, “Genes and Brains” (p. 31)
  • The price we pay for the anticipation of our future is anxiety about it. Foretelling disaster is probably not much fun; Pollyanna was much happier than Cassandra. But the Cassandric components of our nature are necessary for survival.
    • Chapter 3, “The Brain and the Chariot” (p. 74)
  • While ritual, emotion and reasoning are all significant aspects of human nature, the most nearly unique human characteristic is the ability to associate abstractly and to reason. Curiosity and the urge to solve problems are the emotional hallmarks of our species; and the most characteristically human activities are mathematics, science, technology, music and the arts–a somewhat broader range of subjects than is usually included under the “humanities.” Indeed, in its common usage this very word seems to reflect a peculiar narrowness of vision about what is human. Mathematics is as much a “humanity” as poetry.
    • Chapter 3, “The Brain and the Chariot” (pp. 81-82)
  • Evolution often uses this strategy. Indeed, the standard evolutionary practice of increasing the amount of genetic information as organisms increase in complexity is accomplished by doubling part of the genetic material and then allowing the slow specialization of function of the redundant set.
    • Chapter 7, “Lovers and Madmen” (p. 183)
  • There is no doubt that right-hemisphere intuitive thinking may perceive patterns and connections too difficult for the left hemisphere; but it may also detect patterns where none exist. Skeptical and critical thinking is not a hallmark of the right hemisphere. And unalloyed right-hemisphere doctrines, particularly when they are invented during new and trying circumstances, may be erroneous or paranoid.
    • Chapter 7, “Lovers and Madmen” (p. 189)
  • There is no way to tell whether the patterns extracted by the right hemisphere are real or imagined without subjecting them to left-hemisphere scrutiny. On the other hand, mere critical thinking, without creative and intuitive insights, without the search for new patterns, is sterile and doomed. To solve complex problems in changing circumstances requires the activity of both cerebral hemispheres: the path to the future lies through the corpus callosum.
    • Chapter 7, “Lovers and Madmen” (pp. 190-191)
  • The search for patterns without critical analysis, and rigid skepticism without a search for patterns, are the antipodes of incomplete science. The effective pursuit of knowledge requires both functions.
    • Chapter 7, “Lovers and Madmen” (p. 192)
  • Without these experimental tests, very few physicists would have accepted general relativity. There are many hypotheses in physics of almost comparable brilliance and elegance that have been rejected because they did not survive such a confrontation with experiment. In my view, the human condition would be greatly improved if such confrontations and willingness to reject hypotheses were a regular part of our social, political, economic, religious and cultural lives.
    • Chapter 7, “Lovers and Madmen” (p. 193)
  • Anatomy is not destiny, but it is not irrelevant either.
    • Chapter 8, “The Future Evolution of the Brain” (p. 199)
  • In general, human societies are not innovative. They are hierarchical and ritualistic. Suggestions for change are greeted with suspicion: they imply an unpleasant future variation in ritual and hierarchy: an exchange of one set of rituals for another, or perhaps for a less structured society with fewer rituals. And yet there are times when societies must change. “The dogmas of the quiet past are inadequate for the stormy present” was Abraham Lincoln’s description of this truth. Much of the difficulty in attempting to restructure American and other societies arises from this resistance by groups with vested interests in the status quo. Significant change might require those who are now high in the hierarchy to move downward many steps. This seems to them undesirable and is resisted.
    • Chapter 8, “The Future Evolution of the Brain” (p. 199)
  • The integrity of the experimenters in the face of this unexpected finding is breathtaking. (It is difficult to imagine any experiment that would convince leading practitioners of many political or religious philosophies of the superiority of a competing doctrine.)
    • Chapter 8, “The Future Evolution of the Brain” (p. 210)
  • To me it is not in the least demeaning that consciousness and intelligence are the result of “mere” matter sufficiently complexly arranged; on the contrary, it is an exalting tribute to the subtlety of matter and the laws of Nature.
    • Chapter 8, “The Future Evolution of the Brain” (p. 221)
  • That in nonarithmetic operations the small and slow human brain can still do so much better than the large and fast electronic computer is an impressive tribute to how cleverly the brain is packaged and programmed—features brought about, of course, by natural selection. Those who possessed poorly programmed brains eventually did not live long enough to reproduce.
    • Chapter 8, “The Future Evolution of the Brain” (p. 224)
  • The entire evolutionary record on our planet, particularly the record contained in fossil endocasts, illustrates a progressive tendency toward intelligence. There is nothing mysterious about this: smart organisms by and large survive better and leave more offspring than stupid ones.
    • Chapter 9, “Knowledge is Our Destiny: Terrestrial and Extraterrestrial Intelligence” (p. 240)
  • Once intelligent beings achieve technology and the capacity for self-destruction of their species, the selective advantage of intelligence becomes more uncertain.
    • Chapter 9, “Knowledge is Our Destiny: Terrestrial and Extraterrestrial Intelligence” (p. 240)
  • Natural selection has served as a kind of intellectual sieve, producing brains and intelligences increasingly competent to deal with the laws of nature. This resonance, extracted by natural selection, between our brains and the universe may help explain a quandary set by Einstein: The most incomprehensible property of the universe, he said, is that it is so comprehensible.
    • Chapter 9, “Knowledge is Our Destiny: Terrestrial and Extraterrestrial Intelligence” (pp. 242-243)

Broca’s Brain (1979)

All page numbers are from the October 1980 mass market paperback edition published by Ballantine Books ISBN 0-345-33689-5 (28th printing)
  • Both borderline science and many religions are motivated in part by a serious concern about the nature of the universe and our role in it, and for this reason merit our consideration and regard. In addition, I think it possible that many religions involve at their cores an attempt to come to grips with profound mysteries of our individual life histories, as described in the last chapter. But both in borderline science and in organized religion there is much that is specious or dangerous. While the practitioners of such doctrines often wish there were no criticisms to which they are expected to reply, skeptical scrutiny is the means, in both science and religion, by which deep insights can be winnowed from deep nonsense.
    • Introduction (p. xii)
  • The well-meaning contention that all ideas have equal merit seems to me little different from the disastrous contention that no ideas have any merit.
    • Introduction (p. xii)
  • Broca was quoted as saying, “I would rather be a transformed ape than a degenerate son of Adam.”
    • Chapter 1, “Broca’s Brain” (p. 7)
  • Society corrupts the best of us. It is a little unfair, I think, to criticize a person for not sharing the enlightenment of a later epoch, but it is also profoundly saddening that such prejudices were so extremely pervasive. The question raises nagging uncertainties about which of the conventional truths of our own age will be considered unforgivable bigotry by the next.
    • Chapter 1, “Broca’s Brain” (p. 11)
  • All inquiries carry with them some element of risk. There is no guarantee that the universe will conform to our predispositions. But I do not see how we can deal with the universe—both the outside and the inside universe—without studying it. The best way to avoid abuses is for the populace in general to be scientifically literate, to understand the implications of such investigations. In exchange for freedom of inquiry, scientists are obliged to explain their work. If science is considered a closed priesthood, too difficult and arcane for the average person to understand, the dangers of abuse are greater. But if science is a topic of general interest and concern—if both its delights and its social consequences are discussed regularly and competently in the schools, the press, and at the dinner table—we have greatly improved our prospects for learning how the world really is and for improving both it and us.
    • Chapter 1, “Broca’s Brain” (pp. 13-14)
  • Our perceptions may be distorted by training and prejudice or merely because of the limitations of our sense organs, which, of course, perceive directly but a small fraction of the phenomena of the world. Even so straightforward a question as whether in the absence of friction a pound of lead falls faster than a gram of fluff was answered incorrectly by Aristotle and almost everyone else before the time of Galileo. Science is based on experiment, on a willingness to challenge old dogma, on an openness to see the universe as it really is. Accordingly, science sometimes requires courage—at the very least the courage to question the conventional wisdom.
    • Chapter , “” (pp. 15-16)
  • Whether in some sense the universe is ultimately knowable depends not only on how many natural laws there are that encompass widely divergent phenomena, but also on whether we have the openness and the intellectual capacity to understand such laws. Our formulations of the regularities of nature are surely dependent on how the brain is built, but also, and to a significant degree, on how the universe is built.
    For myself, I like a universe that includes much that is unknown and, at the same time, much that is knowable. A universe in which everything is known would be static and dull, as boring as the heaven of some weak-minded theologians. A universe that is unknowable is no fit place for a thinking being. The ideal universe for us is one very much like the universe we inhabit. And I would guess that this is not really much of a coincidence.

    • Chapter 2, “Can We Know the Universe? Reflections on a Grain of Salt” (p. 21)
  • People are rarely grateful for a demonstration of their credulity.
    • Chapter 5, “Night Walkers and Mystery Mongers: Sense and Nonsense at the End of Science” (p. 58)
  • Both Barnum and H. L. Mencken are said to have made the depressing observation that no one ever lost money by underestimating the intelligence of the American public. The remark has worldwide application. But the lack is not in intelligence, which is in plentiful supply; rather, the scarce commodity is systematic training in critical thinking.
    • Chapter 5, “Night Walkers and Mystery Mongers: Sense and Nonsense at the End of Science” (pp. 58-59)
  • For many people, the shoddily thought out doctrines of borderline science are the closest approximation to comprehensible science readily available. The popularity of borderline science is a rebuke to the schools, the press and commercial television for their sparse, unimaginative and ineffective efforts at science education; and to us scientists, for doing so little to popularize our subject.
    • Chapter 5, “Night Walkers and Mystery Mongers: Sense and Nonsense at the End of Science” (p. 63)
  • But our openness to the dazzling possibilities presented by modern science must be tempered by some hard-nosed skepticism. Many interesting possibilities simply turn out to be wrong. An openness to new possibilities and a willingness to ask hard questions are both required to advance our knowledge. And the asking of tough questions has an ancillary benefit: political and religious life in America, especially in the last decade and a half, has been marked by an excessive public credulity, an unwillingness to ask difficult questions, which has produced a demonstrable impairment in our national health. Consumer skepticism makes quality products. This may be why governments and churches and school systems do not exhibit unseemly zeal in encouraging critical thought. They know they themselves are vulnerable.
    • Chapter 5, “Night Walkers and Mystery Mongers: Sense and Nonsense at the End of Science” (pp. 68-69)
  • Very few scientists actually plunge into the murky waters of testing or challenging borderline or pseudo-scientific beliefs. The chance of finding out something really interesting—except about human nature—seems small, and the amount of time required seems large. I believe that scientists should spend more time in discussing these issues, but the fact that a given contention lacks vigorous scientific opposition in no way implies that scientists think it is reasonable.
    • Chapter 5, “Night Walkers and Mystery Mongers: Sense and Nonsense at the End of Science” (p. 69)
  • I believe that the extraordinary should certainly be pursued. But extraordinary claims require extraordinary evidence.
    • Chapter 5, “Night Walkers and Mystery Mongers: Sense and Nonsense at the End of Science” (p. 73)
  • Where skeptical observation and discussion are suppressed, the truth is hidden. The proponents of such borderline beliefs, when criticized, often point to geniuses of the past who were ridiculed. But the fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown..
    • Chapter 5, “Night Walkers and Mystery Mongers: Sense and Nonsense at the End of Science” (p. 75)
  • The best antidote for pseudoscience, I firmly believe, is science.
    • Chapter 5, “Night Walkers and Mystery Mongers: Sense and Nonsense at the End of Science” (p. 75)
  • I believe that even a smattering of such findings in modern science and mathematics is far more compelling and exciting than most of the doctrines of pseudoscience, whose practitioners were condemned as early as the fifth century B.C. by the Ionian philosopher Heraclitus as “nightwalkers, magicians, priests of Bacchus, priestesses of the wine-vat, mystery-mongers.” But science is more intricate and subtle, reveals a much richer universe, and powerfully evokes our sense of wonder. And it has the additional and important virtue—to whatever extent the word has any meaning—of being true.
    • Chapter 5, “Night Walkers and Mystery Mongers: Sense and Nonsense at the End of Science” (p. 76)
  • Scientists, like other human beings, have their hopes and fears, their passions and despondencies—and their strong emotions may sometimes interrupt the course of clear thinking and sound practice. But science is also self-correcting. The most fundamental axioms and conclusions may be challenged. The prevailing hypotheses must survive confrontation with observation. Appeals to authority are impermissible. The steps in a reasoned argument must be set out for all to see. Experiments must be reproducible.
    The history of science is full of cases where previously accepted theories and hypotheses have been entirely overthrown, to be replaced by new ideas that more adequately explain the data. While there is an understandable psychological inertia—usually lasting about one generation—such revolutions in scientific thought are widely accepted as a necessary and desirable element of scientific progress. Indeed, the reasoned criticism of a prevailing belief is a service to the proponents of that belief; if they are incapable of defending it, they are well advised to abandon it. This self-questioning and error-correcting aspect of the scientific method is its most striking property, and sets it off from many other areas of human endeavor where credulity is the rule.

    • Chapter 7, “Venus and Dr. Velikovsky” (p. 96)
  • The idea of science as a method rather than as a body of knowledge is not widely appreciated outside of science, or indeed in some corridors inside of science.
    • Chapter 7, “Venus and Dr. Velikovsky” (p. 96)
  • Vigorous criticism is more constructive in science than in some other areas of human endeavor because in science there are adequate standards of validity that can be agreed upon by competent practitioners the world over. The objective of such criticism is not to suppress but rather to encourage the advance of new ideas: those that survive a firm skeptical scrutiny have a fighting chance of being right, or at least useful.
    • Chapter 7, “Venus and Dr. Velikovsky” (p. 98)
  • It is merely a coincidence. When enough fiction is written and enough scientific hypotheses are proposed, sooner or later there will be accidental concordances.
    • Chapter 7, “Venus and Dr. Velikovsky” (p. 148)
  • St. Anselm argued that since we can imagine a perfect being, he must exist—because he would not be perfect without the added perfection of existence. This so-called ontological argument was more or less promptly attacked on two grounds: (1) Can we imagine a completely perfect being? (2) Is it obvious that perfection is augmented by existence? To the modern ear such pious arguments seem to be about words and definitions rather than about external reality.
    • Chapter 8, “Norman Bloom, Messenger of God” (p. 152)
  • In the face of all this, many of the standard ideas of science fiction seem to me to pale by comparison. I see the relative absence of these things and the distortions of scientific thinking often encountered in science fiction as terrible wasted opportunities. Real science is as amenable to exciting and engrossing fiction as fake science, and I think it is important to exploit every opportunity to convey scientific ideas in a civilization which is both based upon science and does almost nothing to ensure that science is understood.
    • Chapter 9, “Science Fiction—A Personal View” (p. 166)
  • Many scientists deeply involved in the exploration of the solar system (myself among them) were first turned in that direction by science fiction. And the fact that some of that science fiction was not of the highest quality is irrelevant. Ten-year-olds do not read the scientific literature.
    • Chapter 9, “Science Fiction—A Personal View” (p. 172)
  • Every new set of discoveries raises a host of questions which we were never before wise enough even to ask.
    • Chapter 10, “The Sun’s Family” (p. 183)
  • Much of human history can, I think, be described as a gradual and sometimes painful liberation from provincialism, the emerging awareness that there is more to the world than was generally believed by our ancestors.
    • Chapter 16, “The Golden Age of Planetary Exploration” (p. 240)
  • The search for extraterrestrial intelligence is the search for a generally acceptable cosmic context for the human species. In the deepest sense, the search for extraterrestrial intelligence is a search for ourselves.
    • Chapter 22, “The Quest for Extraterrestrial Intelligence” (pp. 314-315)
  • Whether we believe in God depends very much on what we mean by God.
    • Chapter 23, “A Sunday Sermon” (p. 330)
  • A clear prediction in an area undergoing vigorous study permits doctrines to be subject to disproof. The last posture a bureaucratic religion wishes to find itself in is vulnerability to disproof, where an experiment can be performed on which the religion stands or falls.
    • Chapter 23, “A Sunday Sermon” (p. 332)
  • It is astonishing in the face of such transparent evasions that this religion has any adherents at all. But religions are tough. Either they make no contentions which are subject to disproof or they quickly redesign doctrine after disproof. The fact that religions can be so shamelessly dishonest, so contemptuous of the intelligence of their adherents, and still flourish does not speak very well for the tough-mindedness of the believers. But it does indicate, if a demonstration were needed, that near the core of the religious experience is something remarkably resistant to rational inquiry.
    • Chapter 23, “A Sunday Sermon” (pp. 332-333)
  • The idea that a God or gods is necessary to effect one or more of these origins has been under repeated attack over the last few thousand years. Because we know something about phototropism and plant hormones, we can understand the opening of the morning glory independent of divine microintervention. It is the same for the entire skein of causality back to the origin of the universe. As we learn more and more about the universe, there seems less and less for God to do.
    • Chapter 23, “A Sunday Sermon” (p. 335)
  • But there is a chance that the answers will discomfit a great many bureaucratic and doctrinal religions. The idea of religion as a body of belief, immune to criticism, fixed forever by some founder is, I think, a prescription for the long-term decay of the religion, especially lately.
    • Chapter 23, “A Sunday Sermon” (p. 338)
  • The First Amendment to the United States Constitution encourages a diversity of religions but does not prohibit criticism of religion. In fact it protects and encourages criticism of religion. Religions ought to be subject to at least the same degree of skepticism as, for example, contentions about UFO visitations or Velikovskian catastrophism. I think it is healthy for the religions themselves to foster skepticism about the fundamental underpinnings of their evidential bases. There is no question that religion provides a solace and support, a bulwark in time of emotional need, and can serve extremely useful social roles. But it by no means follows that religion should be immune from testing, from critical scrutiny, from skepticism. It is striking how little skeptical discussion of religion there is in the nation that Tom Paine, the author of The Age of Reason, helped to found. I hold that belief systems that cannot survive scrutiny are probably not worth having.
    • Chapter 23, “A Sunday Sermon” (p. 338)
  • The way to find out about our place in the universe is by examining the universe and by examining ourselves—without preconceptions, with as unbiased a mind as we can muster. We cannot begin with an entirely clean slate, since we arrive at this problem with predispositions of hereditary and environmental origin; but, after understanding such built-in biases, is it not possible to pry insights from nature?
    • Chapter 23, “A Sunday Sermon” (p. 339)
  • Proponents of doctrinal religions—ones in which a particular body of belief is prized and infidels scorned—will be threatened by the courageous pursuit of knowledge. We hear from such people that it may be dangerous to probe too deeply. Many people have inherited their religion like their eye color: they consider it not a thing to think very deeply about, and in any case beyond our control. But those with a set of beliefs they profess to feel deeply about, which they have selected without an unbiased sifting through the facts and the alternatives, will feel uncomfortably challenged by searching questions. Anger at queries about our beliefs is the body’s warning signal: here lies unexamined and probably dangerous doctrinal baggage.
    • Chapter 23, “A Sunday Sermon” (pp. 339-340)
  • Some ancient Asian cosmological views are close to the idea of an infinite regression of causes, as exemplified in the following apocryphal story: A Western traveler encountering an Oriental philosopher asks him to describe the nature of the world:
    “It is a great ball resting on the flat back of the world turtle.”
    “Ah yes, but what does the world turtle stand on?”
    “On the back of a still larger turtle.”
    “Yes, but what does he stand on?”
    “A very perceptive question. But it’s no use, mister; it’s turtles all the way down.”

    • Chapter 24, “Gott and the Turtles” , p. 343
  • It is a good idea not to make up our minds prematurely on this issue. It is probably best not to let our personal preferences influence the decision. Rather, in the long tradition of successful science, we should permit nature to reveal the truth to us.
    • Chapter 24, “Gott and the Turtles” (p. 351)
  • In any case, we do not advance the human cause by refusing to consider ideas that make us frightened.
    • Chapter 25, “The Amniotic Universe” (p. 364)
  • We are set irrevocably, I believe, on a path that will take us to the stars—unless in some monstrous capitulation to stupidity and greed, we destroy ourselves first.
    • Chapter 25, “The Amniotic Universe” (p. 368)

Cosmos (1980)

Cosmos. New York: Random House. 1980. LCCQB44.2.S235. ISBN 0394502949.
  • In the vastness of space and the immensity of time, it is my joy to share a planet and an epoch with Annie.
    • Dedication
  • The Cosmos is all that is or ever was or ever will be. Our feeblest contemplations of the Cosmos stir us — there is a tingling in the spine, a catch in the voice, a faint sensation as if a distant memory, of falling from a height. We know we are approaching the greatest of mysteries.
    • p. 4
  • The size and age of the Cosmos are beyond ordinary human understanding. Lost somewhere between immensity and eternity is our tiny planetary home. In a cosmic perspective, most human concerns seem insignificant, even petty. And yet our species is young and curious and brave and shows much promise. In the last few millennia we have made the most astonishing and unexpected discoveries about the Cosmos and our place within it, explorations that are exhilarating to consider. They remind us that humans have evolved to wonder, that understanding is a joy, that knowledge is prerequisite to survival. I believe our future depends powerfully on how well we understand this Cosmos in which we float like a mote of dust in the morning sky.
    • p. 4
  • Imagination will often carry us to worlds that never were. But without it we go nowhere.
    • p. 4
  • We are like butterflies who flutter for a day and think it’s forever.
    • p. 20 [1]
  • The fossil record implies trial and error, an inability to anticipate the future, features inconsistent with an efficient Great Designer.
    • p. 29
  • If a marker were to be erected today, it might read, in homage to his scientific courage: “He preferred the hard truth to his dearest illusions.”
    • On the character of Johannes Kepler, p. 67
  • It is all a matter of time scale. An event that would be unthinkable in a hundred years may be inevitable in a hundred million.
    • p. 73
  • The suppression of uncomfortable ideas may be common in religion and politics, but it is not the path to knowledge; it has no place in the endeavor of science.
    • p. 91
  • With insufficient data it is easy to go wrong.
    • p. 94
  • Our intelligence and our technology have given us the power to affect the climate. How will we use this power? Are we willing to tolerate ignorance and complacency in matters that affect the entire human family? Do we value short-term advantages above the welfare of the Earth? Or will we think on longer time scales, with concern for our children and our grandchildren, to understand and protect the complex life-support systems of our planet? The Earth is a tiny and fragile world. It needs to be cherished.
    • p. 103
  • Human beings have a demonstrated talent for self-deception when their emotions are stirred.
    • p. 135
  • For a long time the human instinct to understand was thwarted by facile religious explanations.
    • p. 173
  • They (i. e., the Pythagoreans) did not advocate the free confrontation of conflicting points of view. Instead, like all orthodox religions, they practised a rigidity that prevented them from correcting their errors.
    • p. 184
  • The Platonists and their Christian successors held the peculiar notion that the Earth was tainted and somehow nasty, while the heavens were perfect and divine. The fundamental idea that the Earth is a planet, that we are citizens of the Universe, was rejected and forgotten.
    • p. 188
  • For as long as there been humans we have searched for our place in the cosmos. Where are we? Who are we? We find that we live on an insignificant planet of a hum-drum star lost in a galaxy tucked away in some forgotten corner of a universe in which there are far more galaxies than people. This perspective is a courageous continuation of our penchant for constructing and testing mental models of the skies; the Sun as a red-hot stone, the stars as a celestial flame, the Galaxy as the backbone of night.
    • p. 193
  • If we long for our planet to be important, there is something we can do about it. We make our world significant by the courage of our questions and by the depth of our answers.
    • p. 193
  • We embarked on our journey to the stars with a question first framed in the childhood of our species and in each generation asked anew with undiminished wonder: What are the stars? Exploration is in our nature. We began as wanderers, and we are wanderers still. We have lingered long enough on the shores of the cosmic ocean. We are ready at last to set sail for the stars.
    • p. 193
  • Astronomically, the U. S. S. R. and the United States are the same place.
    • p. 196
  • Relativity does set limits on what humans can ultimately do. But the universe is not required to be in perfect harmony with human aspirations.
    • p. 201
  • I have…a terrible need…shall I say the word?…of religion. Then I go out at night and paint the stars.
    • Quoting Vincent van Gogh, p. 217
  • If you wish to make an apple pie from scratch, you must first invent the universe.
    • p. 218
  • Matter is composed chiefly of nothing.
    • p. 218
  • A googolplex is precisely as far from infinity as is the number 1… no matter what number you have in mind, infinity is larger still.
    • p. 220
  • The universe seems neither benign nor hostile, merely indifferent to the concerns of such puny creatures as we are.
    • p. 250
  • Nobody listens to mathematicians.
    • p. 262
  • The neurochemistry of the brain is astonishingly busy, the circuitry of a machine more wonderful than any devised by humans. But there is no evidence that its functioning is due to anything more than the 1014 neural connections that build an elegant architecture of consciousness.
    • p. 278
  • Books permit us to voyage through time, to tap the wisdom of our ancestors. The library connects us with the insights and knowledge, painfully extracted from Nature, of the greatest minds that ever were, with the best teachers, drawn from the entire planet and from all of our history, to instruct us without tiring, and to inspire us to make our own contribution to the collective knowledge of the human species. Public libraries depend on voluntary contributions. I think the health of our civilization, the depth of our awareness about the underpinnings of our culture and our concern for the future can all be tested by how well we support our libraries.
    • p. 282
  • Other things being equal, it is better to be smart than to be stupid.
    • p. 284
  • The choice is with us still, but the civilization now in jeopardy is all humanity. As the ancient myth makers knew, we are children equally of the earth and the sky. In our tenure on this planet we’ve accumulated dangerous evolutionary baggage — propensities for aggression and ritual, submission to leaders, hostility to outsiders — all of which puts our survival in some doubt. But we’ve also acquired compassion for others, love for our children and desire to learn from history and experience, and a great soaring passionate intelligence — the clear tools for our continued survival and prosperity. Which aspects of our nature will prevail is uncertain, particularly when our visions and prospects are bound to one small part of the small planet Earth. But up there in the immensity of the Cosmos, an inescapable perspective awaits us. There are not yet any obvious signs of extraterrestrial intelligence and this makes us wonder whether civilizations like ours always rush implacably, headlong, toward self-destruction. National boundaries are not evident when we view the Earth from space. Fanatical ethnic or religious or national chauvinisms are a little difficult to maintain when we see our planet as a fragile blue crescent fading to become an inconspicuous point of light against the bastion and citadel of the stars. Travel is broadening.
    • p. 318
  • War is murder writ large.
    • p. 326
  • We have heard the rationales offered by the nuclear superpowers. We know who speaks for the nations. But who speaks for the human species? Who speaks for Earth?
    • p. 329
  • Those afraid of the universe as it really is, those who pretend to nonexistent knowledge and envision a Cosmos centered on human beings will prefer the fleeting comforts of superstition. They avoid rather than confront the world. But those with the courage to explore the weave and structure of the Cosmos, even where it differs profoundly from their wishes and prejudices, will penetrate its deepest mysteries.
    • p. 332
  • There is no other species on the Earth that does science. It is, so far, entirely a human invention, evolved by natural selection in the cerebral cortex for one simple reason: it works. It is not perfect. It can be misused. It is only a tool. But it is by far the best tool we have, self-correcting, ongoing, applicable to everything. It has two rules. First: there are no sacred truths; all assumptions must be critically examined; arguments from authority are worthless. Second: whatever is inconsistent with the facts must be discarded or revised. We must understand the Cosmos as it is and not confuse how it is with how we wish it to be.
    • p. 333
  • Humanhistory can be viewed as a slowly dawning awareness that we are members of a larger group. Initially our loyalties were to ourselves and our immediate family, next, to bands of wandering hunter-gatherers, then to tribes, small settlements, city-states, nations. We have broadened the circle of those we love. We have now organized what are modestly described as super-powers, which include groups of people from divergent ethnic and cultural backgrounds working in some sense together — surely a humanizing and character building experience. If we are to survive, our loyalties must be broadened further, to include the whole human community, the entire planet Earth. Many of those who run the nations will find this idea unpleasant. They will fear the loss of power. We will hear much about treason and disloyalty. Rich nation-states will have to share their wealth with poor ones. But the choice, as H. G. Wells once said in a different context, is clearly the universe or nothing.
    • p. 339
  • Every one of us is, in the cosmic perspective, precious. If a human disagrees with you, let him live. In a hundred billion galaxies, you will not find another.
    • p. 339
  • We are the local embodiment of a Cosmos grown to selfawareness. We have begun to contemplate our origins: starstuff pondering the stars; organized assemblages of ten billion billion billion atoms considering the evolution of atoms; tracing the long journey by which, here at least, consciousness arose. Our loyalties are to the species and the planet. We speak for Earth. Our obligation to survive is owed not just to ourselves but also to that Cosmos, ancient and vast, from which we spring.

Contact (1985)

Contact : a novel. New York: Simon and Schuster. 1985. LCCPS3569.A287 C6 1985. ISBN 0671434004.
For quotes from the motion picture based on this novel, see: Contact (film)
All page numbers from the mass market paperback edition published by Pocket Books
  • I wish to propose a doctrine which may, I fear, appear wildly paradoxical and subversive. The doctrine in question is this: that it is undesirable to believe a proposition when there is no ground whatever for supposing it true. I must, of course, admit that if such an opinion became common it would completely transform our social life and our political system; since both are at present faultless, this must weigh against it.
    • Chapter 2 (p. 15, quoting Bertrand Russell)
  • Humans are good, she knew, at discerning subtle patterns that are really there, but equally so at imagining them when they are altogether absent.
    • Chapter 3 (p. 44)
  • We could not guess how different from us they (extraterrestrials) might be. It was hard enough to guess the intentions of our elected representatives in Washington.
    • Chapter 3 (p. 48)
  • If we like them, they’re freedom fighters, she thought. If we don’t like them, they’re terrorists. In the unlikely case we can’t make up our minds, they’re temporarily only guerrillas.
    • Chapter 3 (p. 55)
  • If the press descended, the science would surely suffer.
    • Chapter 5 (p. 75)
  • It’s hard to kill a creature once it lets you see its consciousness.
    • Chapter 9 (p. 147)
  • “Let’s see if I’ve got this straight,” he returned. It was a phrase of hers that he had adopted “It’s a lazy Saturday afternoon, and there’s this couple lying naked in bed reading the Encyclopaedia Britannica to each other, and arguing about whether the Andromeda Galaxy is more ‘numinous’ than the Resurrection. Do they know how to have a good time or don’t they?”
    • Chapter 9 (p. 154)
  • Do we, holding that the gods exist,
    deceive ourselves with insubstantial dreams
    and lies, while random careless chance and
    change alone control the world?

    • Chapter 10 (p. 157, quoting Euripides)
  • The major religions on the Earth contradict each other left and right. You can’t all be correct. And what if all of you are wrong? It’s a possibility, you know. You must care about the truth, right? Well, the way to winnow through all the differing contentions is to be skeptical. I’m not any more skeptical about your religious beliefs than I am about every new scientific idea I hear about. But in my line of work, they’re called hypotheses, not inspiration and not revelation.
    • Chapter 10 (p. 162)
  • What I’m saying is, if God wanted to send us a message, and ancient writings were the only way he could think of doing it, he could have done a better job.
    • Chapter 10 (p. 164)
  • Anything you don’t understand, Mr. Rankin, you attribute to God. God for you is where you sweep away all the mysteries of the world, all the challenges to our intelligence. You simply turn your mind off and say God did it.
    • Chapter 10 (p. 166)
  • Jingoistic rhetoric and puerile self-congratulatory nationalism.
    • Chapter 11 (p. 181)
  • Many harebrained interpretations were also widely available, especially in weekly newspapers.
    • Chapter 13 (p. 216)
  • Skepticism is the chastity of the intellect, and it is shameful to surrender it too soon or to the first comer; there is nobility in preserving it coolly and proudly through long youth, until at last, in the ripeness of instinct and discretion, it can be safely exchanged for fidelity and happiness.
    • Chapter 14 (p. 231, quoting George Santayana)
  • A celibate clergy is an especially good idea, because it tends to suppress any hereditary propensity toward fanaticism.
    • Chapter 14 (p. 244)
  • The chiliasts made an atheist out of me.
    • Chapter 15 (p. 258)
  • You see, the religious people — most of them — really think this planet is an experiment. That’s what their beliefs come down to. Some god or other is always fixing and poking, messing around with tradesmen’s wives, giving tablets on mountains, commanding you to mutilate your children, telling people what words they can say and what words they can’t say, making people feel guilty about enjoying themselves, and like that. Why can’t the gods leave well enough alone? All this intervention speaks of incompetence. If God didn’t want Lot’s wife to look back, why didn’t he make her obedient, so she’d do what her husband told her? Or if he hadn’t made Lot such a shithead, maybe she would’ve listened to him more. If God is omnipotent and omniscient, why didn’t he start the universe out in the first place so it would come out the way he wants? Why’s he constantly repairing and complaining? No, there’s one thing the Bible makes clear: The biblical God is a sloppy manufacturer. He’s not good at design, he’s not good at execution. He’d be out of business if there was any competition.
    • Chapter 16 (p. 285)
  • In Mozambique, the story goes, monkeys do not talk, because they know if they utter even a single word some man will come and put them to work.
    • Chapter 18 (p. 313)
  • “Do you understand what’s going on?”
    “Not at all,” he shouted back. “I can almost prove this can’t be happening.”

    • Chapter 19 (p. 330)
  • Humans are very good at dreaming, although you’d never know it from your television.
    • Chapter 20 (p. 359)
  • In the long run, the aggressive civilizations destroy themselves, almost always. It’s their nature. They can’t help it.
    • Chapter 20 (p. 359)
  • That it will never come again
    Is what makes life so sweet.

    • Chapter 22 (p. 393)
    • Quoting Emily Dickinson; The Poems of Emily Dickinson, 3:1171, no. 1741
  • This planet is run by crazy people. Remember what they have to do to get where they are. Their perspective is so narrow, so…brief. A few years. In the best of them a few decades. They care only about the time they are in power.
    • Chapter 23 (p. 403)
  • She too had found the experience transforming. How could she not? A demon had been exorcised. Several. And just when she felt more capable of love than she had ever been, she found herself alone.
    • Chapter 23 (p. 407)
  • For small creatures such as we the vastness is bearable only through love.
    • Chapter 24 (p. 430)
  • The universe was made on purpose, the circle said. In whatever galaxy you happen to find yourself, you take the circumference of a circle, divide it by its diameter, measure closely enough, and uncover a miracle — another circle, drawn kilometers downstream of the decimal point. There would be richer messages farther in. It doesn’t matter what you look like, or what you’re made of, or where you come from. As long as you live in this universe, and have a modest talent for mathematics, sooner or later you’ll find it. It’s already here. It’s inside everything. You don’t have to leave your planet to find it. In the fabric of space and in the nature of matter, as in a greatwork of art, there is, written small, the artist’s signature. Standing over humans, gods, and demons, subsuming Caretakers and Tunnel builders, there is an intelligence that antedates the universe.
    • Chapter 24 (p. 431)

Cosmos: A Personal Voyage (1990 Update)

The Shores of the Cosmic Ocean [Episode 1]

  • For the first time, we have the power to decide the fate of our planet and ourselves. This is a time of great danger, but our species is young, and curious, and brave. It shows much promise.
  • We wish to pursue the truth no matter where it leads — but to find the truth, we need imagination and skepticism both. We will not be afraid to speculate, but we will be careful to distinguish speculation from fact. The cosmos is full beyond measure of elegant truths; of exquisite interrelationships; of the awesome machinery of nature. The surface of the Earth is the shore of the cosmic ocean. On this shore we’ve learned most of what we know. Recently we’ve waded a little way out, maybe ankle deep, and the water seems inviting. Some part of our being knows this is where we came from. We long to return. And we can. Because the cosmos is also within us. We’re made of star-stuff. We are a way for the cosmos to know itself.
    • 5 min 15 sec
  • The cosmic calendar compresses the local history of the universe into a single year. If the universe began on January 1st it was not until May that the Milky Way formed. Other planetary systems may have appeared in June, July and August, but our Sun and Earth not until mid-September. Life arose soon after.
    • 56 min 20 sec
  • We humans appear on the cosmic calendar so recently that our recorded history occupies only the last few seconds of the last minute of December 31st.
    • 57 min 0 sec
  • We on Earth have just awakened to the great oceans of space and time from which we have emerged. We are the legacy of 15 billion years of cosmic evolution. We have a choice: We can enhance life and come to know the universe that made us, or we can squander our 15 billion-year heritage in meaningless self-destruction. What happens in the first second of the next cosmic year depends on what we do, here and now, with our intelligence and our knowledge of the cosmos.

One Voice in the Cosmic Fugue [Episode 2]

  • All my life, I’ve wondered about life beyond the earth. On those countless other planets that we think circle other suns, is there also life? Might the beings of other worlds resemble us, or would they be astonishingly different? What would they be made of? In the vast Milky Way galaxy, how common is what we call life? The nature of life on earth and the quest for life elsewhere are the two sides of the same question: the search for who we are.
    • 0 min 45 sec

The Harmony of the Worlds [Episode 3]

  • As a boy Kepler had been captured by a vision of cosmic splendour, a harmony of the worlds which he sought so tirelessly all his life. Harmony in this world eluded him. His three laws of planetary motion represent, we now know, a real harmony of the worlds, but to Kepler they were only incidental to his quest for a cosmic system based on the Perfect Solids, a system which, it turns out, existed only in his mind. Yet from his work, we have found that scientific laws pervade all of nature, that the same rules apply on Earth as in the skies, that we can find a resonance, a harmony, between the way we think and the way the world works.
    When he found that his long cherished beliefs did not agree with the most precise observations, he accepted the uncomfortable facts, he preferred the hard truth to his dearest illusions. That is the heart of science.

    • 55 min 0 sec

Heaven and Hell [Episode 4]

  • There are many hypotheses in science that are wrong. That’s perfectly alright; it’s the aperture to finding out what’s right. Science is a self-correcting process. To be accepted, new ideas must survive the most rigorous standards of evidence and scrutiny. The worst aspect of the Velikovsky affair is not that many of his ideas were wrong or silly or in gross contradiction to the facts; rather, the worst aspect is that some scientists attempted to suppress Velikovsky’s ideas. The suppression of uncomfortable ideas may be common in religion or in politics, but it is not the path to knowledge and there is no place for it in the endeavor of science. We do not know beforehand where fundamental insights will arise from about our mysterious and lovely solar system, and the history of our study of the solar system shows clearly that accepted and conventional ideas are often wrong and that fundamental insights can arise from the most unexpected sources.
    • 33 min 20 sec

Blues For a Red Planet [Episode 5]

  • The beauty of a living thing is not the atoms that go into it, but the way those atoms are put together. Information distilled over 4 billion years of biological evolution. Incidentally, all the organisms on the Earth are made essentially of that stuff. An eyedropper full of that liquid could be used to make a caterpillar or a petunia if only we knew how to put the components together.
    • 44 min 50 sec

Traveller’s Tales [Episode 6]

  • A tiny blue dot set in a sunbeam. Here it is. That’s where we live. That’s home. We humans are one species and this is our world. It is our responsibility to cherish it. Of all the worlds in our solar system, the only one so far as we know, graced by life.
    • 58 min 56 sec

The Backbone of Night [Episode 7]

  • The sky calls to us. If we do not destroy ourselves, we will one day venture to the stars.
    • 0 min 40 sec
  • There can be an infinite number of polygons, but only five regular solids. Four of the solids were associated with earth, fire, air and water. The cube for example represented earth. These four elements, they thought, make up terrestrial matter. So the fifth solid they mystically associated with the Cosmos. Perhaps it was the substance of the heavens. This fifth solid was called the dodecahedron. Its faces are pentagons, twelve of them. Knowledge of the dodecahedron was considered too dangerous for the public. Ordinary people were to be kept ignorant of the dodecahedron. In love with whole numbers, the Pythagoreans believed that all things could be derived from them. Certainly all other numbers.
    So a crisis in doctrine occurred when they discovered that the square root of two was irrational.
     That is: the square root of two could not be represented as the ratio of two whole numbers, no matter how big they were. “Irrational” originally meant only that. That you can’t express a number as a ratio. But for the Pythagoreans it came to mean something else, something threatening, a hint that their world view might not make sense, the other meaning of “irrational”.

    • 37 min 45 sec
  • Instead of wanting everyone to share and know of their discoveries the Pythagoreans suppressed the square root of two and the dodecahedron. The outside world was not to know. The Pythagoreans had discovered, in the mathematical underpinnings of nature, one of the two most powerful scientific tools, the other of course is experiment, but instead of using their insight to advance the collective voyage of human discovery they made of it little more than the hocus-pocus of a mystery cult. Science and mathematics were to be removed from the hands of the merchants and the artisans.
    • 38 min 10 sec
  • But why had science lost its way in the first place? What appeal could these teachings of Pythagoras and Plato have had for their contemporaries? They provided, I believe, an intellectually respectable justification for a corrupt social order. The mercantile tradition that had led to Ionian science also led to a slave economy. You could get richer if you owned a lot of slaves. Athens in the time of Plato and Aristotle had a vast slave population. All that brave Athenian talk about democracy applied only to a privileged few.
    • 40 min 35 sec

Journeys in Space and Time [Episode 8]

  • We are star stuff, which has taken its destiny into its own hands. The loom of time and space works the most astonishing transformations of matter. Our own planet is only a tiny part of the vast cosmic tapestry, a starry fabric of worlds yet untold. Those worlds in space are as countless as all the grains of sand on all the beaches of the earth. Each of those worlds is as real as ours. In every one of them there’s a succession of incidents, events, occurrences, which influence its future. Countless worlds, numberless moments, an immensity of space and time, and our small planet at this moment — here we face a critical branch point in history. What we do with our world, right now will propagate down through the centuries and powerfully affect the destiny of our descendants. It is well within our power to destroy our civilization and perhaps our species as well. If we capitulate a superstition or greed or stupidity, we can plunge our world into a darkness deeper than the time between the collapse of classical civilization and the Italian Renaissance. But we are also capable of using our compassion and our intelligence, our technology and our wealth, to make an abundant and meaningfullife for every inhabitant of this planet, to enhance enormously our understanding of the universe and to carry us to the stars.
    • 54 min 55 sec

“The Edge of Forever” [Episode 10]

  • But we don’t yet know whether the Universe is open or closed. More than that, there are a few astronomers who doubt that the redshift of distant galaxies is due to the doppler effect, who are skeptical of the expanding Universe and the Big Bang. Perhaps our descendants will regard our present ignorance with as much sympathy as we feel to the ancients for not knowing the Earth went around the Sun. If the general picture, however, of a Big Bang followed by an expanding Universe is correct, what happened before that? Was the Universe devoid of all matter and then the matter suddenly somehow created, how did that happen? In many cultures, the customary answer is that a God or Gods created the Universe out of nothing. But if we wish to pursue this question courageously, we must of course ask the next question: where did God come from? If we decide that this is an unanswerable question, why not save a step and conclude that the origin of the Universe is an unanswerable question? Or, if we say that God always existed, why not save a step, and conclude that the Universe always existed? That there’s no need for a creation, it was always here. These are not easy questions. Cosmology brings us face to face with the deepest mysteries, questions that were once treated only in religion and myth.

The Persistence of Memory [Episode 11]

  • What distinguishes our species is thought. The cerebral cortex is in a way a liberation. We need no longer be trapped in the genetically inherited behavior patterns of lizards and baboons: territoriality and aggression and dominance hierarchies. We are each of us largely responsible for what gets put in to our brains. For what as adults we wind up caring for and knowing about. No longer at the mercy of the reptile brain we can change ourselves. Think of the possibilities.
    • 34 min 00 sec
  • What an astonishing thing a book is. It’s a flat object made from a tree with flexible parts on which are imprinted lots of funny dark squiggles. But one glance at it and you’re inside the mind of another person, maybe somebody dead for thousands of years. Across the millennia, an author is speaking clearly and silently inside your head, directly to you. Writing is perhaps the greatest of human inventions, binding together people who never knew each other, citizens of distant epochs. Books break the shackles of time. A book is proof that humans are capable of working magic.
    • 42 min 33 sec

Encyclopedia Galactica [Episode 12]

  • In the vastness of the Cosmos there must be other civilizations far older and more advanced than ours.
    • 0 min 45 sec
  • What counts is not what sounds plausible, not what we would like to believe, not what one or two witnesses claim, but only what is supported by hard evidence rigorously and skeptically examined. Extraordinary claims require extraordinary evidence.
    • 1 min 10 sec
  • For all I know we may be visited by a different extraterrestrial civilization every second Tuesday, but there’s no support for this appealing idea. The extraordinary claims are not supported by extraordinary evidence.
    • 7 min 25 sec
    • Back reference to UFO abduction claims

Who Speaks for Earth? [Episode 13]

  • The old man made himself look hard at the Raven and saw that it was not a great bird from the sky but the work of men like himself. This first encounter turned out to be peaceful. The men of the La Pérouse expedition were under strict orders to treat with respect any people they might discover, an exceptional policy for its time and after.
    • 4 min 40 sec
  • Unlike the La Pérouse expedition the Conquistadors sought not knowledge but Gold. They used their superior weapons to loot and murder, in their madness they obliterated a civilisation. In the name of piety, in a mockery of their religion, the Spaniards utterly destroyed a society with an Art, Astronomy and Architecture the equal of anything in Europe. We revile the Conquistadors for their cruelty and shortsightedness, for choosing death. We admire La Pérouse and the Tlingit for their courage and wisdom, for choosing life. The choice is with us still, but the civilisation now in jeopardy is all humanity. As the ancient myth makers knew we’re children equally of the earth and the sky. In our tenure on this planet we’ve accumulated dangerous evolutionary baggage, propensities for aggression and ritual, submission to leaders, hostility to outsiders, all of which puts our survival in some doubt. But we’ve also acquired compassion for others, love for our children, a desire to learn from history and experience and a great soaring passionate intelligence, the clear tools for our continued survival and prosperity. Which aspects of our nature will prevail is uncertain, particularly when our visions and prospects are bound to one small part of the small planet Earth. But up there in the Cosmos an inescapable perspective awaits. National boundaries are not evident when we view the Earth from space. Fanatical ethnic or religious or national identifications are a little difficult to support when we see our Earth as a fragile blue crescent fading to become an inconspicuous point of light against the bastion and the citadel of the stars. There are not yet obvious signs of extraterrestrial intelligence and this makes us wonder whether civilisations like ours rush inevitably headlong into self-destruction.
    • 6 min 10 sec
  • Every thinking person fears nuclear war and every technological nation plans for it. Everyone knows it’s madness, and every country has an excuse.
    • 17 min 40 sec
  • Our global civilisation is clearly on the edge of failure and the most important task it faces, preserving the lives and well-being of its citizens and the future habitability of the planet. But if we’re willing to live with the growing likelihood of nuclear war shouldn’t we also been willing to explore vigorously every possible means to prevent nuclear war. Shouldn’t we consider in every nation major changes in the traditional ways of doing things, a fundamental restructuring of economic political social and religious institutions. We’ve reached a point where there can be no more special interests or special cases, nuclear arms threaten every person on the Earth. Fundamental changes in society are sometimes labelled impractical or contrary to human nature, as if nuclear war were practical or as if there’s only one human nature. But fundamental changes can clearly be made, we’re surrounded by them. In the last two centuries abject slavery which was with us for thousands of years has almost entirely been eliminated in a stirring worldwide revolution. Women, systematically mistreated for millennia are gradually gaining the political and economic power traditionally denied them and some wars of aggression have recently been stopped or curtailed because of a revulsion felt by the people in the aggressor nations. The old appeals to racial, sexual, and religious chauvinism and to rabid nationalist fervor are beginning not to work. A new consciousness is developing which sees the earth as a single organism and recognizes that an organism at war with itself is doomed. We are one planet. One of the great revelations of the age of space exploration is the image of the earth finite and lonely, somehow vulnerable, bearing the entire human species through the oceans of space and time.
    • 22 min 35 sec
  • Eratosthenes was the director of the great library of Alexandria, the Centre of science and learning in the ancient world. Aristotle had argued that humanity was divided into Greeks and everybody else, whom he called barbarians and that the Greeks should keep themselves racially pure. He thought it was fitting for the Greeks to enslave other peoples. But Eratosthenes criticized Aristotle for his blind chauvinism, he believed there was good and bad in every nation.
    • 25 Min 10 Sec
  • Imagine how different our world would be if those discoveries had been explained and used for the benefit of everyone, if the humane perspective of Eratosthenes had been widely adopted and applied. But this was not to be. Alexandria was the greatest city the Western world had ever seen. People from all nations came here to live to trade to learn, on a given day these harbours were thronged with merchants and scholars and tourists, it’s probably here that the word Cosmopolitan realised its true meaning of a citizen not just of a nation but of the Cosmos, to be a citizen of the Cosmos. Here were clearly the seeds of our modern world, but why didn’t they take root and flourish why instead did the Western world slumber through a 1000 years of darkness until Columbus and Copernicus and their contemporaries rediscovered the work done here? I cannot give you a simple answer but I do know this, there is no record in the entire history of the library that any of the illustrious scholars and scientists who worked here ever seriously challenged a single political or economic or religious assumption of the society in which they lived. The permanence of the stars was questioned, the justice of slavery was not.
    • 28 min 30 sec
  • History is full of people who out of fear or ignorance or the lust for power have destroyed treasures of immeasurable value which truly belong to all of us. We must not let it happen again.
    • 36 min 20 sec
  • And we who embody the local eyes and ears and thoughts and feelings of the cosmos we’ve begun, at last, to wonder about our origins. Star stuff, contemplating the stars organized collections of 10 billion-billion-billion atoms contemplating the evolution of matter tracing that long path by which it arrived at consciousness here on the planet Earth and perhaps, throughout the cosmos.
    • 53 min 54 sec
  • Our loyalties are to the species and the planet. We speak for Earth. Our obligation to survive and flourish is owed not just to ourselves, but also to that Cosmos, ancient and vast, from which we spring.
    • 54 min 25 sec
  • Since this series’ maiden voyage, the impossible has come to pass: Mighty walls that maintained insuperable ideological differences have come tumbling down; deadly enemies have embraced and begun to work together. The imperative to cherish the Earth and protect the global environment that sustains all of us has become widely accepted, and we’ve begun, finally, the process of reducing the obscene number of weapons of mass destruction. Perhaps we have, after all, decided to choose life. But we still have light years to go to ensure that choice. Even after the summits and the ceremonies and the treaties, there are still some 50,000 nuclear weapons in the world — and it would require the detonation of only a tiny fraction of them to produce a nuclear winter, the predicted global climatic catastrophe that would result from the smoke and the dust lifted into the atmosphere by burning cities and petroleum facilities.
    The world scientific community has begun to sound the alarm about the grave dangers posed by depleting the protective ozone shield and by greenhouse warming, and again we’re taking some mitigating steps, but again those steps are too small and too slow. The discovery that such a thing as nuclear winter was really possible evolved out of the studies of Martian dust storms. The surface of Mars, fried by ultraviolet light, is also a reminder of why it’s important to keep our ozone layer intact. The runaway greenhouse effect on Venus is a valuable reminder that we must take the increasing greenhouse effect on Earth seriously.
    Important lessons about our environment have come from spacecraft missions to the planets. By exploring other worlds we safeguard this one. By itself, I think this fact more than justifies the money our species has spent in sending ships to other worlds. It is our fate to live during one of the most perilous and, at the same time, one of the most hopeful chapters in human history.
    Our science and our technology have posed us a profound question. Will we learn to use these tools with wisdom and foresight before it’s too late?
     Will we see our species safely through this difficult passage so that our children and grandchildren will continue the great journey of discovery still deeper into the mysteries of the Cosmos? That same rocket and nuclear and computer technology that sends our ships past the farthest known planet can also be used to destroy our global civilization. Exactly the same technology can be used for good and for evil. It is as if there were a God who said to us, “I set before you two ways: You can use your technology to destroy yourselves or to carry you to the planets and the stars. It’s up to you.”

    • 55 min 20 sec

Pale Blue Dot: A Vision of the Human Future in Space (1994)

Pale blue dot : a vision of the human future in space. New York: Random House. 1994. LCCQB500.262.S24 1994. ISBN 0679438416.
  • For all its material advantages, the sedentary life has left us edgy, unfulfilled. Even after 400 generations in villages and cities, we haven’t forgotten. The open road still softly calls, like a nearly forgotten song of childhood. We invest far-off places with a certain romance. This appeal, I suspect, has been meticulously crafted by natural selection as an essential element in our survival. Long summers, mild winters, rich harvests, plentiful game—none of them lasts forever. It is beyond our powers to predict the future. Catastrophic events have a way of sneaking up on us, of catching us unaware. Your own life, or your band’s, or even your species’ might be owed to a restless few—drawn, by a craving they can hardly articulate or understand, to undiscovered lands and new worlds.
    Herman Melville, in Moby Dick, spoke for wanderers in all epochs and meridians: “I am tormented with an everlasting itch for things remote. I love to sail forbidden seas…”

    • p. 2
  • Consider again that dot. That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every “superstar”, every “supreme leader”, every saint and sinner in the history of our species lived there — on a mote of dust suspended in a sunbeam.
    The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds.
    Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.
    The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand.
    It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we’ve ever known.

    • p. 8, Supplemental image at randi.org
  • Ann Druyan suggests an experiment: Look back again at the pale blue dot of the preceding chapter. Take a good long look at it. Stare at the dot for any length of time and then try to convince yourself that God created the whole Universe for one of the 10 million or so species of life that inhabit that speck of dust. Now take it a step further: Imagine that everything was made just for a single shade of that species, or gender, or ethnic or religious subdivision. If this doesn’t strike you as unlikely, pick another dot. Imagine it to be inhabited by a different form of intelligent life. They, too, cherish the notion of a God who has created everything for their benefit. How seriously do you take their claim?
    • p. 11
  • It took the Church until 1832 to remove Galileo’s work from its list of books which Catholics were forbidden to read at the risk of dire punishment of their immortal souls.
    • p. 43
  • We’ve tended in our cosmologies to make things familiar. Despite all our best efforts, we’ve not been very inventive. In the West, Heaven is placid and fluffy, and Hell is like the inside of a volcano. In many stories, both realms are governed by dominance hierarchies headed by gods or devils. Monotheists talked about the king of kings. In every culture we imagined something like our own political system running the Universe. Few found the similarity suspicious.
    • p. 46
  • In some respects, science has far surpassed religion in delivering awe. How is it that hardly any major religion has looked at science and concluded, “This is better than we thought! The Universe is much bigger than our prophets said, grander, more subtle, more elegant. God must be even greater than we dreamed”? Instead they say, “No, no, no! My god is a little god, and I want him to stay that way.”
    • p. 50
  • Once we overcome our fear of being tiny, we find ourselves on the threshold of a vast and awesome Universe that utterly dwarfs — in time, in space, and in potential — the tidy anthropocentric proscenium of our ancestors. We gaze across billions of light-years of space to view the Universe shortly after the Big Bang, and plumb the fine structure of matter. We peer down into the core of our planet, and the blazing interior of our star. We read the genetic language in which is written the diverse skills and propensities of every being on Earth. We uncover hidden chapters in the record of our origins, and with some anguish better understand our nature and prospects. We invent and refine agriculture, without which almost all of us would starve to death. We create medicines and vaccines that save the lives of billions. We communicate at the speed of light, and whip around the Earth in an hour and a half. We have sent dozens of ships to more than seventy worlds, and four spacecraft to the stars. We are right to rejoice in our accomplishments, to be proud that our species has been able to see so far, and to judge our merit in part by the very science that has so deflated our pretensions.
    • p. 53
  • It is sometimes said that scientists are unromantic, that their passion to figure out robs the world of beauty and mystery. But is it not stirring to understand how the world actually works — that white light is made of colors, that color is the way we perceive the wavelengths of light, that transparent air reflects light, that in so doing it discriminates among the waves, and that the sky is blue for the same reason that the sunset is red? It does no harm to the romance of the sunset to know a little bit about it.
    • p. 159
  • Those who are skeptical about carbon dioxide greenhouse warming might profitably note the massive greenhouse effect on Venus. No one proposes that Venus’s greenhouse effect derives from imprudent Venusians who burned too much coal, drove fuel-inefficient autos, and cut down their forests. My point is different. The climatological history of our planetary neighbor, an otherwise Earthlike planet on which the surface became hot enough to melt tin or lead, is worth considering — especially by those who say that the increasing greenhouse effect on Earth will be self-correcting, that we don’t really have to worry about it, or (you can see this in the publications of some groups that call themselves conservative) that the greenhouse effect is a “hoax”.
    • p. 227
  • A scientific colleague tells me about a recent trip to the New Guinea highlands where she visited a stone age culture hardly contacted by Western civilization. They were ignorant of wristwatches, soft drinks, and frozen food. But they knew about Apollo 11. They knew that humans had walked on the Moon. They knew the names of Armstrong and Aldrin and Collins. They wanted to know who was visiting the Moon these days.
    • p. 281
  • Since, in the long run, every planetary society will be endangered by impacts from space, every surviving civilization is obliged to become spacefaring — not because of exploratory or romantic zeal, but for the most practical reason imaginable: staying alive.
    • p. 371
  • Imagine we could accelerate continuously at 1 g — what we’re comfortable with on good old terra firma — to the midpoint of our voyage, and decelerate continuously at 1 g until we arrive at our destination. It would take a day to get to Mars, a week and a half to Pluto, a year to the Oort Cloud, and a few years to the nearest stars.
    • p. 395
  • The vast distances that separate the stars are providential. Beings and worlds are quarantined from one another. The quarantine is lifted only for those with sufficient self-knowledge and judgement to have safely traveled from star to star.
    • p. 398
  • Modern science has been a voyage into the unknown, with a lesson in humility waiting at every stop. Many passengers would rather have stayed home.
  • If we crave some cosmic purpose, then let us find ourselves a worthy goal.

The Demon-Haunted World : Science as a Candle in the Dark (1995)

The demon-haunted world : science as a candle in the dark. New York: Random House. 1995. LCCQ175.S215 1995. ISBN 039453512X.
  • Advances in medicine and agriculture have saved vastly more lives than have been lost in all the wars in history.
    • Ch. 1 : The Most Precious Thing
  • If we long to believe that the stars rise and set for us, that we are the reason there is a Universe, does science do us a disservice in deflating our conceits?
    • Ch. 1 : The Most Precious Thing, p. 12
  • For me, it is far better to grasp the Universe as it really is than to persist in delusion, however satisfying and reassuring.
    • Ch. 1 : The Most Precious Thing, p. 12
  • I have a foreboding of an America in my children’s or grandchildren’s time — when the United States is a service and information economy; when nearly all the manufacturing industries have slipped away to other countries; when awesome technological powers are in the hands of a very few, and no one representing the public interest can even grasp the issues; when the people have lost the ability to set their own agendas or knowledgeably question those in authority; when, clutching our crystals and nervously consulting our horoscopes, our critical faculties in decline, unable to distinguish between what feels good and what’s true, we slide, almost without noticing, back into superstition and darkness.
    • Ch. 2 : Science and Hope, p. 25
  • We’ve arranged a global civilization in which the most crucial elements — transportation, communications, and all other industries; agriculture, medicine, education, entertainment, protecting the environment; and even the key democratic institution of voting, profoundly depend on science and technology. We have also arranged things so that almost no one understands science and technology. This is a prescription for disaster. We might get away with it for a while, but sooner or later this combustible mixture of ignorance and power is going to blow up in our faces.
    • Ch. 2 : Science and Hope, p. 26
  • Humans may crave absolute certainty; they may aspire to it; they may pretend, as partisans of certain religions do, to have attained it. But the history of science — by far the most successful claim to knowledge accessible to humans — teaches that the most we can hope for is successive improvement in our understanding, learning from our mistakes, an asymptotic approach to the Universe, but with the proviso that absolute certainty will always elude us.
    • Ch. 2 : Science and Hope, p. 28
  • I worry that, especially as the Millennium edges nearer, pseudo-science and superstition will seem year by year more tempting, the siren song of unreason more sonorous and attractive. Where have we heard it before? Whenever our ethnic or national prejudices are aroused, in times of scarcity, during challenges to national self-esteem or nerve, when we agonize about our diminished cosmic place and purpose, or when fanaticism is bubbling up around us-then, habits of thought familiar from ages past reach for the controls. The candle flame gutters. Its little pool of light trembles. Darkness gathers. The demons begin to stir.
    • Ch. 2 : Science and Hope
  • I try not to think with my gut. If I’m serious about understanding the world, thinking with anything besides my brain, as tempting as that might be, is likely to get me into trouble. Really, it’s okay to reserve judgment until the evidence is in.
    • Ch. 11 : The Dragon in My Garage, p. 180
  • Appeal to ignorance — the claim that whatever has not been proved false must be true, and vice versa (e.g. There is no compelling evidence that UFOs are not visiting the Earth; therefore UFOs exist — and there is intelligent life elsewhere in the universe. Or: There may be seventy kazillion other worlds, but not one is known to have the moral advancement of the Earth, so we’re still central to the Universe.) This impatience with ambiguity can be criticized in the phrase: absence of evidence is not evidence of absence.
    • Ch. 12 : The Fine Art of Baloney Detection, p. 221
    • Referring to an aphorism of Martin Rees. (see Misattributed below)
  • One of the saddest lessons of history is this: If we’ve been bamboozled long enough, we tend to reject any evidence of the bamboozle. We’re no longer interested in finding out the truth. The bamboozle has captured us. It’s simply too painful to acknowledge, even to ourselves, that we’ve been taken. Once you give a charlatan power over you, you almost never get it back.
    • Ch. 13 : Obsessed with Reality, p. 241
  • At the heart of science is an essential balance between two seemingly contradictory attitudes – an openness to new ideas, no matter how bizarre or counterintuitive, and the most ruthlessly skeptical scrutiny of all ideas, old and new. This is how deep truths are winnowed from deep nonsense. The collective enterprise of creative thinking and skeptical thinking, working together, keeps the field on track. Those two seemingly contradictory attitudes are, though, in some tension.
    • Ch. 17 : The Marriage of Skepticism and Wonder
  • Books, purchasable at low cost, permit us to interrogate the past with high accuracy; to tap the wisdom of our species; to understand the point of view of others, and not just those in power; to contemplate — with the best teachers — the insights, painfully extracted from Nature, of the greatest minds that ever were, drawn from the entire planet and from all of our history. They allow people long dead to talk inside our heads. Books can accompany us everywhere. Books are patient where we are slow to understand, allow us to go over the hard parts as many times as we wish, and are never critical of our lapses. Books are key to understanding the world and participating in a democratic society.
    • Ch. 21 : The Path to Freedom, p. 357
  • Education on the value of free speech and the other freedoms reserved by the Bill of Rights, about what happens when you don’t have them, and about how to exercise and protect them, should be an essential prerequisite for being an American citizen — or indeed a citizen of any nation, the more so to the degree that such rights remain unprotected. If we can’t think for ourselves, if we’re unwilling to question authority, then we’re just putty in the hands of those in power. But if the citizens are educated and form their own opinions, then those in power work for us. In every country, we should be teaching our children the scientific method and the reasons for a Bill of Rights. With it comes a certain decency, humility and community spirit. In the demon-haunted world that we inhabit by virtue of being human, this may be all that stands between us and the enveloping darkness.
    • Ch. 25 : Real Patriots Ask Questions
  • When we consider the founders of our nation: Jefferson, Washington, Samuel and John Adams, Madison and Monroe, Benjamin Franklin, Tom Paine and many others; we have before us a list of at least ten and maybe even dozens of great political leaders. They were well educated. Products of the European Enlightenment, they were students of history. They knew human fallibility and weakness and corruptibility. They were fluent in the English language. They wrote their own speeches. They were realistic and practical, and at the same time motivated by high principles. They were not checking the pollsters on what to think this week. They knew what to think. They were comfortable with long-term thinking, planning even further ahead than the next election. They were self-sufficient, not requiring careers as politicians or lobbyists to make a living. They were able to bring out the best in us. They were interested in and, at least two of them, fluent in science. They attempted to set a course for the United States into the far future — not so much by establishing laws as by setting limits on what kinds of laws could be passed. The Constitution and its Bill of Rights have done remarkably well, constituting, despite human weaknesses, a machine able, more often than not, to correct its own trajectory. At that time, there were only about two and a half million citizens of the United States. Today there are about a hundred times more. So if there were ten people of the caliber of Thomas Jefferson then, there ought to be 10 x 100 = 1,000 Thomas Jefferson’s today. Where are they?
    • Ch. 25 : Real Patriots Ask Questions

Billions and Billions: Thoughts on Life and Death at the Brink of the Millenium (1997)

Billions and billions : thoughts on life and death at the brink of the millennium. New York: Random House. 1997. LCCQ173.S24 1997. ISBN 0679411607.
  • I never said it. Honest. Oh, I said there are maybe 100 billion galaxies and 10 billion trillion stars. It’s hard to talk about the Cosmos without using big numbers. I said ‘billion’ many times on the Cosmos television series, which was seen by a great many people. But I never said ‘billions and billions.’ For one thing, it’s imprecise. How many billions are ‘billions and billions’? A few billion? Twenty billion? A hundred billion? ‘Billions and billions’ is pretty vague… For a while, out of childish pique, I wouldn’t utter the phrase, even when asked to. But I’ve gotten over that. So, for the record, here it goes: ‘Billions and billions.’
    • List of misquotations
  • If we keep on with business as usual, the Earth will be warmed more every year; drought and floods will be endemic; many more cities, provinces, and whole nations will be submerged beneath the waves — unless heroic worldwide engineering countermeasures are taken. In the longer run, still more dire consequences may follow, including the collapse of the West Antarctic ice sheet, and the inundation of almost all the coastal cities on the planet.
    • Chapter 11, “Ambush: The Warming of the World”
  • A central lesson of science is that to understand complex issues (or even simple ones), we must try to free our minds of dogma and to guarantee the freedom to publish, to contradict, and to experiment. Arguments from authority are unacceptable.
    • Chapter 14, “The Common Enemy”.
  • Widespread intellectual and moral docility may be convenient for leaders in the short term, but it is suicidal for nations in the long term. One of the criteria for national leadership should therefore be a talent for understanding, encouraging, and making constructive use of vigorous criticism.
    • Chapter 14, “The Common Enemy”

The Varieties of Scientific Experience: A Personal View of the Search for God (2006)

version of Carl Sagan’s Gifford Lectures, The Search for Who We Are (1985) edited by Ann Druyan
  • Superstition is marked not by its pretension to a body of knowledge but by its method of seeking truth.
  • I stress that the universe is made mostly of nothing, that something is the exception.
  • This vast number of worlds, the enormous scale of the universe… has not been taken into account, even superficially, in virtually no religion, and especially in no Western religions.
  • Many religions have attempted to make statues of their gods very large, and the idea, I suppose, is to make us feel small. But if that’s their purpose, they can keep their paltry icons. We need only look up if we wish to feel small.
  • In many myths, the one possibility the gods are most anxious about is that humans will discover some secret of immortality or even… attempt to stride the high heavens. …It’s a little bit like the rich imposing poverty on the poor and then asking to be loved because of it.
  • A general problem with much of Western theology… is that the God portrayed is too small. It is a god of a tiny world and not a god of a galaxy, much less a universe.
  • If we seek… nature, then love can be informed by truth instead of being based on ignorance or self-deception.
  • If a Creator God exists, would He or She or It… prefer a kind of sodden blockhead who worships while understanding nothing? Or would He prefer His votaries to admire the real universe in all its intracacy?
  • Science is, at least in part, informed worship.
  • The enterprise of knowledge is consistent surely with science; it should be with religion, and it is essential for the welfare of the human species.
  • The idea that as I walk in this direction my watch goes slightly slower and I am contracted in the direction of motion and my mass has increased slightly does not correspond to everyday experience. …the reason that it does not correspond to common sense is that we are not in the habit of traveling close to the speed of light. We may one day be in that habit, and then the Lorentz transformations will be natural, intuitive.
  • If I were to propose to you that my arm could be in this position or in that position but it would be forbidden by the laws of nature to be in some intermediate position, that would likely strike you as absurd, as contrary to experience. And yet on the subatomic level, there is a quantization of energy and position and momentum. The reason that it seems counterintuitive is that is that we are not ordinarily down at the level of the very small, where quantum effects dominate.
  • The history of science—especially physics—has in part been the tension between the natural tendency to project our everyday experience on the universe and the universe’s noncompliance
  • Projected upon the natural world… is the idea of privilege. …Ever since the invention of civilization, there have been privileged classes… some groups that oppress others and that work to maintain these heirarchies of power. The children of the privileged grow up expecting that, through no particular effort of their own, they will retain a privileged position.
  • At birth all of us imagine that we are the universe, and we don’t distinguish the boundaries between ourselves and those around us. …in some social situations, there is the sense that we are central, important. …there was a natural projection of those attitudes upon the universe.
  • Once upon a time, the best minds of the human species believed that the planets were attached to crystal spheres. …Both in classic and in medieval times, it was prominently speculated that gods or angels propelled them, gave them a twirl every now and then. The Newtonian gravitational superstructure replaced angels with GMm/r2… as science advances, there seems to be less and less for God to do.
  • Evolving before our eyes has been a God of the Gaps; that is, whatever it is we cannot explain lately is attributed to God.
  • Suppose your father… walked into this room at the ordinary human pace of walking. And suppose just behind him was his father. How long would we have to wait before the ancestor who enters the now-open door is a creature who normally walked on all fours? The answer is a week.
  • When you look more generally at life on Earth, you find that it is all the same kind of life. …It uses about fifty fundamental biological building blocks, organic molecules. …with trivial exceptions, all organisms on Earth use… an enzyme, to control the rate and direction of the chemistry of life. …a nucleic acid to encode the hereditary information …the identical code book for translating nucleic acid language into protein language. …At the molecular level, we are all virtually identical.
  • This image of four spectra is taken from one of Huggins’s publications. …You can see that the Comet Winnecke resembles olive oil more than it does Comet Brorsen.
  • Let’s go back to the solar nebula… with the temperature declining the farther we get from the Sun. …at different distances from the Sun, different materials will condense out, because they have different vapor pressures or different melting points. …water condenses out roughly at the vicinity of the Earth, whereas silicates condense out closer to the Sun… you have to go out to somewhere near the present distance of Saturn before methane condenses.
  • We find a set of data that strongly implies the presence of complex organic molecules in the outer solar system.
  • Carbonaceous meteorites that fall to the Earth… have several percent to as much as 10 percent of complex organic matter in them.
  • This is Phobos… Its mean density is known, and it is consistent with organic matter. Deimos… same story.
  • The organic molecules found in the gas phase in the atmosphere of Titan by Voyager 1 and 2 spacecraft include hydrogen cyanide, cyanoacetylene, butadiene. cyanogen, propylene, propane, acetylene, ethane, ethylene, Methane, likewise. And the principle constituent of the atmosphere, there as here, is molecular nitrogen. It is, I think, very interesting that we have a world in the outer solar system that is loaded with the stuff of life.
  • There is a very stunning range of studies… of interstellar organic matter… the cold, dark spaces between the stars are also loaded with organic matter. …complex organic materials are everywhere.
  • The amount of organic matter that could have been produced in the first few hundred million years of Earth history was sufficient to have produced in the present ocean a several-percent solution of organic matter. This is just about the dilution of Knorr’s chicken soup, and not that different from the composition either. And chicken soup is widely known to be good for life.
  • The origin of life happened in significantly less than 500 million years. …Six days was once a popular hypothesis. …A process that happens quickly is a process that is in some sense likely… this evidence suggests that the origin of life was in some sense easy, in some sense sitting in the laws of physics and chemistry.
  • If there’s nothing in here but atoms, does that make us less or does that make matter more?
  • Let’s say there’s a molecule that produces a religious experience… a natural molecule that the body produces whose function it is to produce religious experiences, at least on occasion? …So let’s call it “theophorin”…What could the selective advantage of theophorin be? …to suit us for the quest that was, according to Dostoyevsky, to strive for nothing so incessantly and so painfully as to find someone to worship and obey.
  • There is no question that religions have historically played the role of making people contented with their lot. …such a doctrine would be very appealing to the ruling classes of a society. …Many societies, for this reason alone, encourage the contentment with your lot that the religious premise of heaven affords.
  • Many religions lay out a set of precepts… and claim that these instructions were given by a god or gods. For example, the first code of law by Hammurabi of Babylon… was handed to him by the god Marduk… this is a bamboozle… a pious hoax. …if Hammurabi had merely said, “Here’s what I think everybody should do,” he would have been much less successful
  • There is in the lovely Martian landscape not a footprint, not an artifact, not even an old beer can, not a blade of grass, not a kangaroo rat, not even, so far as we can tell, a microbe. Mars and the Moon and Venus… the only planets that we’ve landed on—are utterly lifeless. …in our solar system we may discover that there is life only on this world. This says that life is not guaranteed, that life requires something special, something improbable.
  • Because it is clear from the fossil record that almost every species that has ever existed is extinct; extinction is the rule, survival is the exception.

Others

  • The prediction I can make with the highest confidence is that the most amazing discoveries will be the ones we are not today wise enough to foresee.
    • Cited in Tim Flannery, Atmosphere of Hope. Solutions to the Climate Crisis, Penguin Books, 2015, pages 162 ISBN 9780141981048.
  • We go about our daily lives understanding almost nothing of the world. We give little thought to the machinery that generates the sun light that makes life possible, to the gravity that glues us to an Earth that would otherwise sent us spinning off into space, or to the atoms of which we are made and on whose stability we fundamentally depend. Few of us spend much time wondering why nature is the way it is, where the cosmos came from, or whether it was always there, if time will one day flow backwards or whether there are ultimate limits to what humans can know. What is the smallest piece of matter, why we remember the past and not the future, and why there is the universe?
    • [citation needed]
  • The whole idea of what happens when you read a book, I find absolutely stunning. Here’s some product of a tree, little black squiggles on it, you open it up, an inside your head is the voice of someone speaking, who may have been dead 3000 years, and there he is talking directly to you, what a magical thing that is.
    • Carl Sagan on The Tonight Show with Johnny Carson (full interview, May 20th, 1977)
  • When there isn’t enough food, the body has to make a decision on how to invest the limited foodstuff available to it. Survival comes first, growth comes second. And in this kind of nutritional triage, the body seems obliged to rank learning, last. It sort of it’s better to be stupid and alive, than smart and dead.
    • Carl Sagan on Literacy & Nutrition – Cornell University – 1994

Misattributed

  • Somewhere, something incredible is waiting to be known.
    • This phrase was created by reporter Sharon Begley in the end of a 1977 Newsweek article with an extended profile of Carl Sagan. It was a final conclusion about Sagan’s work and the topic of hypotethical extra-terrestrial life forms. “Quote Investigator”
  • If we are alone in the Universe, it sure seems like an awful waste of space.
    • This is a paraphrase of Sagan quoting Thomas Carlyle: “A sad spectacle. If they be inhabited, what a scope for misery and folly. If they be not inhabited, what a waste of space.”
    • Sagan delivered this quote during the symposium on “Life Beyond Earth and the Mind of Man”, held at Boston University (20 November 1972), published in Life Beyond Earth and the Mind of Man (1973) edited by Richard Berendzen; Life Beyond Earth and the Mind of Man (1975) National Archives video
  • Atheism is more than just the knowledge that gods do not exist, and that religion is either a mistake or a fraud. Atheism is an attitude, a frame of mind that looks at the world objectively, fearlessly, always trying to understand all things as a part of nature.
    • Emmett F. Fields, in “Atheism : An Affirmative View” (1980)
  • Absence of evidence is not evidence of absence.
    • Martin Rees — Sagan refers to this quote in The Demon-Haunted World (1995) (see above)
  • If it can be destroyed by the truth, it deserves to be destroyed by the truth.
    • “That which can be destroyed by the truth, should be.” — P. C. Hodgell, in her 1994 novel Seeker’s Mask.
  • You can’t convince a believer of anything; for their belief is not based on evidence, it’s based on a deep seated need to believe.
    • Sometimes attributed to Contact (1985), but the quote does not appear in that book.
    • It appears attributed to Sagan in Judson Poling’s 2003 book “Do Science and the Bible Conflict?”[1], but without source.

Quotes about Sagan

  • “This is a deathwatch,” Carl told me calmly. “I’m going to die.” “No,” I protested. “You’re going to beat this, just as you have before when it looked hopeless.” He turned to me with that same look I had seen countless times in the debates and skirmishes of our twenty years of writing together and being wildly in love. With a mixture of knowing good humor and skepticism, but as ever, not a trace of self-pity, he said wryly, “Well, well see who’s right about this one.” Sam, now five years old, came to see his father for one last time. Although Carl was by now struggling for breath and finding it harder to speak, he managed to compose himself so as not to frighten his little son. “I love you, Sam,” was all he could say. “I love you, too, Daddy,” Sam said solemnly. Contrary to the fantasies of the fundamentalists, there was no deathbed conversion, no last minute refuge taken in a comforting vision of a heaven or an afterlife. For Carl, what mattered most was what was true, not merely what would make us feel better. Even at this moment when anyone would be forgiven for turning away from the reality of our situation, Carl was unflinching. As we looked deeply into each other’s eyes, it was with a shared conviction that our wondrous life together was ending forever.
    • Ann Druyan, Epilogue to Carl Sagan’s last book Billions and Billions (1997), p. 271
  • When my husband died, because he was so famous and known for not being a believer, many people would come up to me—it still sometimes happens—and ask me if Carl changed at the end and converted to a belief in an afterlife. They also frequently ask me if I think I will see him again. Carl faced his death with unflagging courage and never sought refuge in illusions. The tragedy was that we knew we would never see each other again. I don’t ever expect to be reunited with Carl. But, the great thing is that when we were together, for nearly twenty years, we lived with a vivid appreciation of how brief and precious life is. We never trivialized the meaning of death by pretending it was anything other than a final parting. Every single moment that we were alive and we were together was miraculous-not miraculous in the sense of inexplicable or supernatural. We knew we were beneficiaries of chance. … That pure chance could be so generous and so kind. … That we could find each other, as Carl wrote so beautifully in Cosmos, you know, in the vastness of space and the immensity of time. … That we could be together for twenty years. That is something which sustains me and it’s much more meaningful. … The way he treated me and the way I treated him, the way we took care of each other and our family, while he lived. That is so much more important than the idea I will see him someday. I don’t think I’ll ever see Carl again. But I saw him. We saw each other. We found each other in the cosmos, and that was wonderful.
    • Ann Druyan, “Ann Druyan Talks About Science, Religion, Wonder, Awe … and Carl Sagan”, The Skeptical Inquirer Vol. 27, no. 6 (November/December 2003), p. 30
  • The work of Carl Sagan has been a profound influence in my life, and the life of every individual who recognizes the importance of humanity’s ongoing commitment to the exploration of our universe.
    • Seth MacFarlane, as quoted in Seth MacFarlane donates Carl Sagan’s papers to Library of Congress, Los Angeles Times, 28 June 2012.
  • As astronomer Carl Sagan thought about what Fermi said [Fermi paradox], he began to be alarmed. …This could only mean that advanced civilizations destroy themselves before they get that far, a viewpoint Sagan published in 1966.
    • Stanley A. Rice, Life of Earth: Portrait of a Beautiful, Middle-aged Stressed-out World (2011) Referencing: Intelligent Life in the Universe by Iosif S. Shklovsky and Sagan
  • Sagan’s first wife, Lynn Margulis, was one of the principal architects of the Gaia Hypothesis. Put their viewpoints together, and the conclusion you would reach would be that nuclear war could have a significant enough effect that it could even kill Gaia.
    • Stanley A. Rice, Life of Earth: Portrait of a Beautiful, Middle-aged Stressed-out World (2011)
  • Carl Sagan… examined the cures from cancer that resulted from a visit to Lourdes… where people were healed by a simple contact with the holy waters, and found… that, of the total cancer patients who visited… the cure rate was, if anything, lower than the statistical one for spontaneous remissions. It was lower than the average for those who did not go to Lourdes. Should a statistician infer that… odds of survival deteriorate after a visit..?
    • Nassim Nicholas Taleb, Fooled by Randomness: The Hidden Role of Chance in Life and in the Markets (2001) Nine: It is Easier to Buy and Sell than to Fry an Egg | Comparative Luck | Cancer Cures
  • I was applying to colleges in high school and I already knew I wanted to study the universe at age seventeen because I knew at age nine. So my applications were dripping with the universe. I was accepted at Cornell, and it’s time to decide what school you go to, and a set of other schools as well. The admissions office, unknown to me, sent my application to Carl Sagan. He was already famous. He was already on Johnny Carson, Tonight Show. To get him to just comment on it. Carl Sagan then sent me a letter, hand signed, saying, ‘I understand you’re considering Cornell. If you come by and visit I’d be happy to show you the lab.’ And I said, ‘Is this Carl Sagan?’ I showed it to mom, dad, I said, ‘Could this be?’ And it was. I wrote back and I said, ‘Yeah, I’ll go up in two weekends.’ He met me on a Saturday morning in the snow, gave me a tour of his lab. I’m in his office, he reaches back, pulls out one of his books, signs it to me. It’s time for me to leave, he drives me to the bus station, snowing a little heavier. He writes his home phone on a sheet of paper, says, ‘If the bus can’t get through, call me, spend the night at our place.’ And I thought to myself, who am I? I’m just some high school kid. And to this day, to this day, I have this duty to respond to students who are inquiring about the universe as a career path, to respond to them in the way that Carl Sagan had responded to me.
    • Neil deGrasse Tyson, in a Horizon interview with Ted Simons (Youtube Video), 2009.
  • I do not regard the late Carl Sagan as any kind of authority. On the contrary, as this book will show, I regard him in many ways as a dubious publicity seeker and careerist, more concerned to maintain his reputation as the brilliant and sceptical representative of hard-headed science than to look squarely and honestly at the facts. In short, a bit of a crook.
    • Colin Wilson, in Alien Dawn (1998)
  • Global nuclear war could have a major impact on climate—manifested by significant surface darkening over many weeks, subfreezing land temperatures persisting for up to several months, large perturbations in global circulation patterns, and dramatic changes in local weather and precipitation rates—a harsh “nuclear winter” in any season. [Co-author with Carl Sagan] Richard P. Turco

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