Following the intellectual drama of Aristotle's chapter on greatness of soul, the rest of Book IV covers gentleness (of which the contraries are an angry or docile disposition) and a few social excellences like benevolence, modesty, and wit. It might not be coincidental that all of these act as counterweights to the haughty arrogance we just witnessed in the great-souled man.
The discussion of gentleness and anger (IV.5) has several interesting wrinkles. For one, Aristotle observes that the gentle-minded person is undisturbed (atarachos) and not led by passions, using the same root word that Epicurus will later emphasize in his ethics of ataraxia. Here Aristotle also graphically illustrates the many ways that a person can go astray emotionally: the irritable person gets angry quickly and at the wrong kinds of people, but just as quickly cools off; the hot-head is sharp-tempered toward everyone; the bitter person doesn't let go of angry feelings; the harsh person gets angry for the wrong reasons; and so forth.
The social excellences that Aristotle considers in IV.6-8 are traditionally thought of as minor virtues, yet they set the stage for his exploration of justice in Book V and friendship/love (philia) in Books VII and VIII. All of them lend authenticity/truth (aletheia), decency/humaneness (epieikeia), and grace/civility (charis) to social relations, living harmoniously, and sharing words and deeds with the other people in our daily life and community. They are not matters for legislation, but "a free and gracious person will conduct his life this way, since he is like a law unto himself" (NE 1128a31-32). Especially as he grows older, this kind of decent person won't experience feelings of shame because he won't engage in shameful acts in the first place - instead, in all the many and various situations of life he will deviate as little as possible from what is admirably appropriate and beautifully right.
At this point, having sketched out a number of character traits outside the traditional "big four" of ancient Greek culture, Aristotle will devote the entirety of Book V to an examination of justice. That's a large topic, so I'll probably split it into several different posts.
(Cross-posted at philosopher.coach.)
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