As for AIDS, it's a plague. We are human, we get plagues. They come along every so often, kill off two thirds of the population; in the next generation it's a quarter; after that it's a childhood disease.

Intelligence is just a tool to be used toward a goal, and goals are not always chosen intelligently.

Everything starts as somebody's daydream.

Never fire a laser at a mirror.

In challenging a kzin, a simple scream of rage is sufficient. You scream and you leap.

Consider the true picture. Think of myriads of tiny bubbles, very sparsely scattered, rising through a vast black sea. We rule some of the bubbles. Of the waters we know nothing.

The Gods do not protect fools. Fools are protected by more capable fools.