The commentary on Nicomachean Ethics 2 opens on Aristotle’s sentence that intellectual virtue comes mostly from teaching: you also need nature, and it is bound up with wisdom (virtue of theoretical nous) and phronēsis (virtue of practical nous). Hence it needs empeiria and time. Ethical virtue comes from ethos; the name ēthikē is from ethos. Nothing that is by nature can be habituated otherwise: a stone will never be habituated to go up. So the ethical virtues are neither by nature nor against nature.
The commentator then follows the mean, pleasure and pain as the matter of ethical virtue, Plato on training the young to rejoice and grieve at the right things, and the objection from apatheia. Milo of Croton is the example of a relative mean in diet: what is little for him is much for another. He once carried a bull the length of the stadium; he held up a sagging house for his Pythagorean companions.
The slot is that Byzantine exegesis of Aristotle on virtue, not a missing ethicist.
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