The man who backbites an absent friend, nay, who does not stand up for him when another blames him, the man who angles for bursts of laughter and for the repute of a wit, who can invent what he never saw, who cannot keep a secret -- that man is black at heart: mark and avoid him.

It is a shameful thing to be weary of inquiry when what we search for is excellent.

The life of the dead is placed in the memory of the living.

Nature herself makes the wise man rich.

I am never less alone than when alone.

Rightly defined philosophy is simply the love of wisdom.

It is difficult to persuade mankind that the love of virtue is the love of themselves.