If a conclusion is not poetically balanced, it cannot be scientifically true.

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.

And above all things, never think that you're not good enough yourself. A man should never think that. My belief is that in life people will take you at your own reckoning.

Whenever I have endured or accomplished some difficult task -- such as watching television, going out socially or sleeping -- I always look forward to rewarding myself with the small pleasure of getting back to my typewriter and writing something.

One might accept death reasoningly, with every aspect of the conscious mind, but the body was a brute beast that knew nothing of reason.

Modern science fiction is the only form of literature that consistently considers the nature of the changes that face us.

Old men tend to forget what thought was like in their youth; they forget the quickness of the mental jump, the daring of the youthful intuition, the agility of the fresh insight. They become accustomed to the more plodding varieties of reason, and because this is more than made up by the accumulation of experience, old men think themselves wiser than the young.