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.”

“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.”

“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.”

“Something dreadful happens to students between first and twelfth grades, and it's not just puberty.”

“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.”

“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?”

“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.”

“I think people in power have a vested interest to oppose critical thinking.”

“Now, there has been the view that ... if there is nothing special about us in space then maybe there is something special about us in time. ... To me, the principal trouble with this idea is that 99.998% of the lifetime of the universe, from its beginning to now, was over before humans appeared on the scene.”

“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.”

“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.”

“Absence of evidence is not evidence of absence.”

“Those at too great a distance may, I am well aware, mistake ignorance for perspective.”

“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.”

“It is important to distinguish between the amount of information and the quality of that information.”

“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.”

“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.”

“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.”

“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.”

“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.”

“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.”

“Anatomy is not destiny, but it is not irrelevant either.”

“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.)”

“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.”

“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.”

“Once intelligent beings achieve technology and the capacity for self-destruction of their species, the selective advantage of intelligence becomes more uncertain.”

“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.”

“Broca was quoted as saying, “I would rather be a transformed ape than a degenerate son of Adam.””

“People are rarely grateful for a demonstration of their credulity.”

“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.”