“Though the man-apes often fought and wrestled one another, their disputes very seldom resulted in serious injuries. Having no claws or fighting canine teeth, and being well protected by hair, they could not inflict much harm on one another. In any event, they had little surplus energy for such unproductive behavior; snarling and threatening was a much more efficient way of asserting their points of view.”

“Imagine that you're an intelligent extraterrestrial, concerned only with verifiable truths. You discover a species that has divided itself into thousands - no, by now millions - of tribal groups holding an incredible variety of beliefs about the origin of the universe and the way to behave in it. Although many of them have ideas in common, even when there's 99% overlap, the remaining one percent's enough to set them killing and torturing each other, over trivial points of doctrine, utterly meaningless to outsiders. "How to account for such irrational behavior? (...) religion was the by-product of fear - a reaction to a mysterious and often hostile universe. For much of human prehistory, it may have been a necessary evil - but why was it so much more evil than necessary - and why did it survive when it was no longer necessary?”

“A man who grows that much hair,' critics were fond of saying, 'must have a lot to hide.”

“This is the first age that's ever paid much attention to the future, which is a little ironic since we may not have one.”

“It is a good principle in science not to believe any 'fact'---however well attested---until it fits into some accepted frame of reference. Occasionally, of course, an observation can shatter the frame and force the construction of a new one, but that is extremely rare. Galileos and Einsteins seldom appear more than once per century, which is just as well for the equanimity of mankind.”

“Much blood has also been spilled on the carpet in attempts to distinguish between science fiction and fantasy. I have suggested an operational definition: science fiction is something that COULD happen - but usually you wouldn't want it to. Fantasy is something that COULDN'T happen - though often you only wish that it could.”

“But he knew well enough that any man in the right circumstances could be dehumanised by panic.”