It is fear and terror that make all men brave, except the philosophers. Yet it is illogical to be brave through fear and cowardice.

If a man says that it is right to give every one his due, and therefore thinks within his own mind that injury is due from a just man to his enemies but kindness to his friends, he was not wise who said so, for he spoke not the truth, for in no case has it appeared to be just to injure any one.

Good people do not need laws to tell them to act responsibly, while bad people will find a way around the laws.

There must always remain something that is antagonistic to good.

Mathematics is like draughts in being suitable for the young, not too difficult, amusing, and without peril to the state.

I would have you imagine, then, that there exists in the mind of man a block of wax... and that we remember and know what is imprinted as long as the image lasts; but when the image is effaced, or cannot be taken, then we forget or do not know.

It is beautiful to wish to add another's light to your own.