He who is to be a good ruler must have first been ruled.

No notice is taken of a little evil, but when it increases it strikes the eye.

For we do not think that we know a thing until we are acquainted with its primary conditions or first principles, and have carried our analysis as far as its simplest elements.

I say that habit's but a long practice, friend, and this becomes men's nature in the end.

It is just that we should be grateful, not only to those with whose views we may agree, but also to those who have expressed more superficial views; for these also contributed something, by developing before us the powers of thought.

Health is a matter of choice, not a mystery of chance

The happy life is thought to be one of excellence; now an excellent life requires exertion, and does not consist in amusement.