The "Nicomachean Ethics" is the most significant ethical work of Aristotle (384-322 BC). It provides a guide on how to become a good person and lead a happy life. At the center of this sober yet thoughtful analysis are the concepts of happiness, virtue, choice, wisdom, lack of self-control, pleasure, and friendship. The aim is to avoid the extremes of excess or deficiency and to find that "mean" which alone enables virtue and individual happiness. Aristotle's discussions are by no means only of historical interest; they also exert a decisive influence on contemporary ethical debates. Anyone interested in a theory of moral or humane practice will find in the "Nicomachean Ethics" one of the few relevant foundational models still applicable today. Translated by Olof Gigon.