Never worry about theory as long as the machinery does what it's supposed to do.

By cultivating the beautiful we scatter the seeds of heavenly flowers, as by doing good we cultivate those that belong to humanity.

To be matter-of-fact about the world is to blunder into fantasy - and dull fantasy at that, as the real world is strange and wonderful.

No statement should be believed because it is made by an authority.

It's an indulgence to sit in a room and discuss your beliefs as if they were a juicy piece of gossip.

You can have peace. Or you can have freedom. Don't ever count on having both at once.

Yield to temptation. It may not pass your way again.

Writing is not necessarily something to be ashamed of, but do it in private and wash your hands afterwards.

Women and cats will do as they please, and men and dogs should relax and get used to the idea.

When a place gets crowded enough to require ID's, social collapse is not far away. It is time to go elsewhere. The best thing about space travel is that it made it possible to go elsewhere.

They didn't want it good, they wanted it Wednesday.

There is no way that writers can be tamed and rendered civilized or even cured. The only solution known to science is to provide the patient with an isolation room, where he can endure the acute stages in private and where food can be poked in to him with a stick.

Theology is never any help; it is searching in a dark cellar at midnight for a black cat that isn't there. Theologians can persuade themselves of anything.

One man's theology is another man's belly laugh.

The supreme irony of life is that hardly anyone gets out of it alive.