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.
The soul of animals is characterized by two faculties, (a) the faculty of discrimination which is the work of thought and sense, and (b) the faculty of originating local movement.
Happiness, then, is co-extensive with contemplation, and the more people contemplate, the happier they are; not incidentally, but in virtue of their contemplation, because it is in itself precious. Thus happiness is a form of contemplation.
Demonstration is also something necessary, because a demonstration cannot go otherwise than it does, ... And the cause of this lies with the primary premises/principles.
The happy man . . . will be always or at least most often employed in doing and contemplating the things that are in conformity with virtue. And he will bear changes of fortunes most nobly, and with perfect propriety in every way.
It makes no difference whether a good man has defrauded a bad man, or a bad man defrauded a good man, or whether a good or bad man has committed adultery: the law can look only to the amount of damage done.
It is the activity of the intellect that constitutes complete human happiness - provided it be granted a complete span of life, for nothing that belongs to happiness can be incomplete.