The proof that you know something is that you are able to teach it

Where perception is, there also are pain and pleasure, and where these are, there, of necessity, is desire.

Man's best friend is one who wishes well to the object of his wish for his sake, even if no one is to know of it.

And this activity alone would seem to be loved for its own sake; for nothing arises from it apart from the contemplating, while from practical activities we gain more or less apart from the action. And happiness is thought to depend on leisure; for we are busy that we may have leisure, and make war that we may live in peace.

As the pleasures of the body are the ones which we most often meet with, and as all men are capable of these, these have usurped the family title; and some men think these are the only pleasures that exist, because they are the only ones which they know.

The shape of the heaven is of necessity spherical; for that is the shape most appropriate to its substance and also by nature primary.

There is a cropping-time in the races of men, as in the fruits of the field; and sometimes, if the stock be good, there springs up for a time a succession of splendid men; and then comes a period of barrenness.