I'm quite fond of the writer who told a beginning author, "If you've got a message, use Western Union."

I have encountered a few "creationists" and because they were usually nice, intelligent people, I have been unable to decide whether they were really mad or only pretending to be mad. If I was a religious person, I would consider creationism nothing less than blasphemy. Do its adherents imagine that God is a cosmic hoaxer who has created the whole vast fossil record for the sole purpose of misleading humankind?

I don't believe in astrology; I'm a Sagittarius and we're skeptical.

Deep beneath the surface of the Sun, enormous forces were gathering. At any moment, the energies of a million hydrogen bombs might burst forth in the awesome explosion.... Climbing at millions of miles per hour, an invisible fireball many times the size of Earth would leap from the Sun and head out across space.

The best measure of a man's honesty isn't his income tax return. It's the zero adjust on his bathroom scale.

Isaac Asimov is, in reality, based on something I had invented a few years previously.

In all the universe there is nothing more precious than mind.