The West needs to relearn what the rest of the world has never forgotten - that there is nothing sinful in leisure as long as it does not degenerate into mere sloth.

I want to be remembered most as a writer - one who entertained readers, and, hopefully, stretched their imagination as well.

The greatest tragedy in mankind's entire history may be the hijacking of morality by religion.

One can imagine a time when men who still inhabit organic bodies are regarded with pity by those who have passed on to an infinitely richer mode of existence, capable of throwing their consciousness or sphere of attention instantaneously to any point on land, sea, or sky where there is a suitable sensing organ. In adolescence we leave childhood behind; one day there may be a second and more portentous adolescence, when we bid farewell to the flesh.

Before the current decade ends, fee-paying passengers will be experiencing suborbital flights aboard privately funded vehicles. . . . It won't be too long before bright young men and women set their eyes on careers in Earth orbit and say: "I want to work 200 kilometers from home-straight up!"

When beauty is universal, it loses its power to move the heart, and only its absence can produce any emotional effect.

I sometimes think that the universe is a machine designed for the perpetual astonishment of astronomers.