Aristophanes

The wise learn many things from their enemies.

Men of sense often learn from their enemies. It is from their foes, not their friends, that cities learn the lesson of building high walls and ships of war . . .

By words the mind is winged.

You have all the characteristics of a popular politician: a horrible voice, bad breeding, and a vulgar manner.

This is what extremely grieves us, that a man who never fought
Should contrive our fees to pilfer, on who for his native land
Never to this day had oar, or lance, or blister in his hand.

Let each man exercise the art he knows.

Under every stone lurks a politician.

Shall I crack any of those old jokes, master,
At which the audience never fail to laugh?

High thoughts must have high language.

A man's homeland is wherever he prospers.

Quickly, bring me a beaker of wine, so that I may wet my mind and say something clever.

A man may learn wisdom even from a foe.