Human beings are curious by nature.

To Unlearn is as hard as to Learn

Man first begins to philosophize when the necessities of life are supplied.

He who can be, and therefore is, another's, and he who participates in reason enough to apprehend, but not to have, is a slave by nature.

The wise man knows of all things, as far as possible, although he has no knowledge of each of them in detail

Two characteristic marks have above all others been recognized as distinguishing that which has soul in it from that which has not - movement and sensation.

It is the repeated performance of just and temperate actions that produces virtue.