Whetstones are not themselves able to cut, but make iron sharp and capable of cutting.

And let no one suppose that I claim that just living can be taught for, in a word, I hold that there does not exist an art of the kind which can implant sobriety and justice into depraved natures. Nevertheless, I do think that the study of political discourse can help more than any other thing to stimulate and form such qualities of character

Always when you are about to say anything, first weigh it in your mind; for with many the tongue outruns the thought.

Of all our possessions, wisdom alone is immortal.

Make no man your friend before inquiring how he has used his former friends; for you must expect him to treat you as he has treated them. Be slow to give your friendship, but when you have given it, strive to make it lasting; for it is as reprehensible to make many changes in one's associates as to have no friends at all. Neither test your friends to your own injury nor be willing to forego a test of your companions.

Conduct yourself towards your parents as you would have your children conduct themselves towards you.

We should not call a city happy because it attracts masses of citizens from everywhere; a fortunate city is one in which the race of the original inhabitants is best preserved.