The goal of the future is full unemployment, so we can play. That's why we have to destroy the present politico-economic system.

One theory which can no longer be taken very seriously is that UFOs are interstellar spaceships.

Humor was the enemy of desire.

As our own species is in the process of proving, one cannot have superior science and inferior morals. The combination is unstable and self-destroying.

Only feeble minds are paralyzed by facts.

Attempting to define science fiction is an undertaking almost as difficult, though not so popular, as trying to define pornography... In both pornography and SF, the problem lies in knowing exactly where to draw the line.

I can never look now at the Milky Way without wondering from which of those banked clouds of stars the emissaries are coming. If you will pardon so commonplace a simile, we have set off the fire alarm and have nothing to do but to wait. I do not think we will have to wait for long.