Do not do to others what angers you if done to you by others.

It is never right to do wrong or to requite wrong with wrong, or when we suffer evil to defend ourselves by doing evil in return.

I do not believe in immortality of the individual, and I consider ethics to be an exclusively human concern with no superhuman authority behind it.

The noblest worship is to make yourself as good and as just as you can.

A system of morality that is based on relative emotional values is a mere illusion, a thoroughly vulgar conception that has nothing sound in it and nothing true.

Slavery is founded in the selfishness of man's nature - opposition to it is [in] his love of justice.