All art, all education, can be merely a supplement to nature.

Why is it that all those who have become eminent in philosophy, politics, poetry, or the arts are clearly of an atrabilious temperament and some of them to such an extent as to be affected by diseases caused by black bile?

A sense is what has the power of receiving into itself the sensible forms of things without the matter, in the way in which a piece of wax takes on the impress of a signet-ring without the iron or gold.

...virtue is not merely a state in conformity with the right principle, but one that implies the right principle; and the right principle in moral conduct is prudence.

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.

For even they who compose treatises of medicine or natural philosophy in verse are denominated Poets: yet Homer and Empedocles have nothing in common except their metre; the former, therefore, justly merits the name of the Poet; while the other should rather be called a Physiologist than a Poet.

And of course, the brain is not responsible for any of the sensations at all. The correct view is that the seat and source of sensation is the region of the heart.