Cats have no sense of humor, they have terribly inflated egos, and they are very touchy.

Analogy is even slipperier than logic.

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.

Any group is weaker than a man alone unless they are perfectly trained to work together.

Of all the nonsense that twists the world, the concept of 'altruism' is the worst. People do what they want to, every time. If it pains them to make a choice - if the choice looks like a 'sacrifice' - you can be sure that it is no nobler than the discomfort caused by greediness... the necessity of deciding between two things you want when you can't have both.

Library Science is the key to all science, just as mathematics is its language - and civilization will rise or fall, depending on how well librarians do their jobs.

Most gods have the manners and morals of a spoiled child.