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Carl Sagan

284 quotes

“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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...”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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 hierarchies of power. The children of the privileged grow up expecting that, through no particular effort of their own, they will retain a privileged position.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“Evolving before our eyes has been a God of the Gaps; that is, whatever it is we cannot explain lately is attributed to God.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“We find a set of data that strongly implies the presence of complex organic molecules in the outer solar system.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“Carbonaceous meteorites that fall to the Earth... have several percent to as much as 10 percent of complex organic matter in them.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“This is Phobos... Its mean density is known, and it is consistent with organic matter. Deimos... same story.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“If there's nothing in here but atoms, does that make us less or does that make matter more?”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“The hope that if they had intervened many times in human history, surely in the present time, a time of great crisis recognized in the 1960s and '70s and manifestly clear today in the age of fifty-five thousand nuclear weapons, that the extraterrestrials would come and prevent us from doing the worst to ourselves. And in that sense 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 (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“Now, it is sometimes said that people who take a skeptical approach to UFOs or ancient astronauts or indeed some varieties of revealed religion are engaging in prejudice. I maintain that this is not prejudice. It is postjudice. That is, not a judgement made before examining the evidence but a judgement made after examining the evidence.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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...”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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 (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
Recorded in: Cited in Tim Flannery, Atmosphere of Hope. Solutions to the Climate Crisis, Penguin Books, 2015, pages 162 .
“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, and 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 (1934–1996) first seen 1977 wikiquote, CC BY-SA 4.0 source
Recorded in: 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 (1934–1996) first seen 1994 wikiquote, CC BY-SA 4.0 source
Recorded in: Carl Sagan on Literacy & Nutrition - Cornell University - 1994
“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 (1934–1996) first seen 1970 wikiquote, CC BY-SA 4.0 source
Recorded in: Planetary Exploration (University of Oregon Books, Eugene, Oregon, 1970), page 15
“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 (1934–1996) first seen 1995 wikiquote, CC BY-SA 4.0 source
Recorded in: In Wonder and Skepticism, Skeptical Inquirer (Jan-Feb 1995), 19, No. 1.
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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 (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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 (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
Recorded in: Conversations with Carl Sagan (2006), edited by Tom Head, p. 70
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source
“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.”
Carl Sagan (1934–1996) said by 1996 at the latest wikiquote, CC BY-SA 4.0 source