Never appeal to a man's 'better nature.' He may not have one. Invoking his self-interest gives you more leverage.

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

Happiness consists in getting enough sleep. Just that, nothing more.

If a thing's worth doing, it's worth overdoing. (Lazarus Long)

The second best thing about space travel is that the distances involved make war very difficult, usually impractical, and almost always unnecessary. This is probably a loss for most people, since war is our race's most popular diversion, one which gives purpose and color to dull and stupid lives. But it is a great boon to the intelligent man who fights only when he must-never for sport.

Selfishness is the bedrock on which all moral behavior starts and it can be immoral only when it conflicts with a higher moral imperative.

Once a month, some women act like men act all the time.