For what one has to learn to do, we learn by doing.

To enjoy the things we ought and to hate the things we ought has the greatest bearing on excellence of character.

It is clear, then, that wisdom is knowledge having to do with certain principles and causes. But now, since it is this knowledge that we are seeking, we must consider the following point: of what kind of principles and of what kind of causes is wisdom the knowledge?

We must as second best, as people say, take the least of the evils.

This much then, is clear: in all our conduct it is the mean that is to be commended.

The moral virtues, then, are produced in us neither by nature nor against nature. Nature, indeed, prepares in us the ground for their reception, but their complete formation is the product of habit.

The soul is characterized by these capacities; self-nutrition, sensation, thinking, and movement.