You should not honor men more than truth.

The greatest penalty of evil-doing is to grow into the likeness of bad men, and, growing like them, to fly from the conversation of the good, and be cut off from them, and cleave to and follow after the company of the bad.

O youth or young man, who fancy that you are neglected by the gods, know that if you become worse, you shall go to worse souls, or if better to the better... In every succession of life and death, you will do and suffer what like may fitly suffer at the hands of like. This is the justice of heaven.

To do injustice is more disgraceful than to suffer it.

Man is a wingless animal with two feet and flat nails.

True opinions are a fine thing and do all sorts of good so long as they stay in their place; but they will not stay long. They run away from a man's mind, so they are not worth much until you tether them by working out the reason. Once they are tied down, they become knowledge, and are stable.

And tell him it's quite true that the best of the philosophers are of no use to their fellows; but that he should blame, not the philosophers, but those who fail to make use of them.