The Nicomachean Ethics

The work, which plays a pre-eminent role in defining Aristotelian ethics, consists of ten books, originally separate scrolls, and is understood to be based on notes from his lectures at the Lyceum, which were either edited by or dedicated to Aristotle's son, Nicomachus. The Nicomachean Ethics is widely considered one of the most important historical philosophical works, and had an important impact upon the European Middle Ages, becoming one of the core works of medieval philosophy.