『The Nicomachean Ethics』要約

Aristotle’s *The Nicomachean Ethics* is a foundational work of moral philosophy, likely compiled from lecture notes and named for his son Nicomachus. It asks what the human good is and argues that it is *eudaimonia*—often translated as happiness or flourishing—an activity of the soul in accordance with virtue, not merely a feeling or a reward. The book’s central framework is the function argument: since every thing has a characteristic activity, the human good consists in performing reason-guided activity excellently over a complete life. Aristotle distinguishes intellectual virtues, such as practical wisdom (*phronesis*) and theoretical wisdom, from character virtues, such as courage, temperance, and generosity. These character virtues are stable dispositions, acquired through habit and practice, that hit a mean between excess and deficiency—courage between cowardice and recklessness, for example—relative to the person and situation. A second distinctive contribution is his analysis of choice, voluntariness, and responsibility, including discussions of involuntary action, ignorance, and moral weakness (*akrasia*), the puzzling case of knowing what is good yet acting against it. He also treats justice extensively, separating distributive, corrective, and reciprocal justice. Friendship occupies two entire books, with three kinds—utility, pleasure, and virtue—the last being complete and enduring. Pleasure is examined not as evil but as completing virtuous activity. Book Ten returns to *eudaimonia*, arguing that contemplative activity is the highest happiness, while also discussing habituation and the role of law in forming good character. The work ends by linking ethics to politics and legislation.