Ninety percent of all human wisdom is the ability to mind your own business.

And suddenly I knew I was people and could not stop laughing.

Reason is poor propaganda when opposed by the yammering, unceasing lies of shrewd and evil and self-serving men.

Progress isn't made by early risers. It's made by lazy men trying to find easier ways to do something.

It is better to copulate than never.

Remember this: once the human race is established on more than one planet and especially, in more than one solar system, there is no way now imaginable to kill off the human race.

Money problems can always be solved by a man not frightened by them.