We can't learn without pain.

Nature creates nothing without a purpose.

If one way be better than another, that you may be sure is nature's way.

People become house builders through building houses, harp players through playing the harp. We grow to be just by doing things which are just.

The soul never thinks without a picture.

A likely impossibility is always preferable to an unconvincing possibility.

There are, then, these three means of effecting persuasion. The man who is to be in command of them must, it is clear, be able (1) to reason logically, (2) to understand human character and goodness in their various forms, and (3) to understand the emotions--that is, to name them and describe them, to know their causes and the way in which they are excited.