The more you know, the more you know you don't know.

Now the soul of man is divided into two parts, one of which has a rational principle in itself, and the other, not having a rational principle in itself, is able to obey such a principle. And we call a man in any way good because he has the virtues of these two parts.

The energy or active exercise of the mind constitutes life.

It is evident that the state is a creation of nature, and that man is by nature a political animal.

Wonder implies the desire to learn.

Also, that which is desirable in itself is more desirable than what is desirable per accidens.

It is simplicity that makes the uneducated more effective than the educated when addressing popular audiences.