Since emotions are few and reasons are many (said the robot Giscard) the behavior of a crowd can be more easily predicted than the behavior of one person.

Although the time of death is approaching me, I am not afraid of dying and going to Hell or (what would be considerably worse) going to the popularized version of Heaven. I expect death to be nothingness and, for removing me from all possible fears of death, I am thankful to atheism.

The dangers that face the world can, every one of them, be traced back to science. The salvations that may save the world will, every one of them, be traced back to science.

I have never written a book that didn't teach me far more than it taught my reader.

On Earth, we are unmanned by our longing for a pastoral past that never really existed; and that, if it had existed, could never exist again...on the Moon, there is no past to long for or dream about. There is no direction but forward.

I believe in evidence. I believe in observation, measurement, and reasoning, confirmed by independent observers. I'll believe anything, no matter how wild and ridiculous, if there is evidence for it. The wilder and more ridiculous something is, however, the firmer and more solid the evidence will have to be.

Life would be impossible on such a planet. It wouldn't get enough heat and light, and if it rotated there would be total darkness half of every day. There wouldn't be any native inhabitants. You couldn't expect life - which is fundamentally dependent on light - to develop under such extreme conditions of light deprivation. Half of every axial rotation spent in Darkness! No, nothing could exist under conditions like that.