Analogy is even slipperier than logic.

When I don’t understand, I have an unbearable itch to know why.

I think that science fiction has a distinct therapeutic value because all of it has as its primary postulate that the world does change. I cannot overemphasize the importance of that idea.

Men are not potatoes!

A society that gets rid of all its troublemakers goes downhill.

Consider the black widow spider. It's a timid little beastie, useful and, for my taste, the prettiest of the arachnids, with its shiny, patent-leather finish and its red hourglass trademark. But the poor thing has the fatal misfortune of possessing enormously too much power for its size. So everybody kills it on sight.

Spacemen - men who work in space, pilots and jetmen and astrogators and such - are men who like a few million miles of elbow room.