At two-tenths the speed of light, dust and atoms might not do significant damage even in a voyage of 40 years, but the faster you go, the worse it is--space begins to become abrasive. When you begin to approach the speed of light, hydrogen atoms become cosmic-ray particles, and they will fry the crew. ...So 60,000 kilometers per second may be the practical speed limit for space travel.

University President: Why is it that you physicists always require so much expensive equipment? Now the Department of Mathematics requires nothing but money for paper, pencils, and erasers . . . and the Department of Philosophy is better still. It doesn't even ask for erasers.

Human beings sometimes find a kind of pleasure in nursing painful emotions, in blaming themselves without reason or even against reason.

Until I became a published writer, I remained completely ignorant of books on how to write and courses on the subject ... they would have spoiled my natural style; made me observe caution; would have hedged me with rules.

Fertility is hereditary. If your parents didn't have any children, neither will you. I do not fear computers. I fear the lack of them.

There is a single light of science, and to brighten it anywhere is to brighten it everywhere.

When I read about the way in which library funds are being cut and cut, I can only think that American society has found one more way to destroy itself.