When asked what learning was the most necessary, he said, “Not to unlearn what you have learned!”

Once when Bion was at sea in the company of some wicked men, he fell into the hands of pirates; and when the rest said, "We are undone if we are known,"-"But I," said he, "am undone if we are not known.

Diogenes would frequently praise those who were about to marry, and yet did not marry.

If appearances are deceitful, then they do not deserve any confidence when they assert what appears to them to be true.

Antisthenes used to say that envious people were devoured by their own disposition, just as iron is by rust.

Diogenes lighted a candle in the daytime, and went round saying, "I am looking for a man.

Heraclitus says that Pittacus, when he had got Alcæus into his power, released him, saying, "Forgiveness is better than revenge.