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.

May you live as long as you wish and love as long as you live.

Sin is cruelty and injustice, all else is peccadillo. Oh, a sense of sin comes from violating the customs of your tribe. But breaking custom is not sin even when it feels so; sin is wronging another person.

Sense is never common.

Take big bites. Anything worth doing is worth overdoing.

Most people who sneer at technology would starve to death if the engineering infrastructure were removed.

Autobiography is usually honest but it is never truthful.