Aristotle wrote two treatises on ethics, which have come down to us as the Nicomachean Ethics or NE (in ten books) and the Eudemian Ethics or EE (in eight books). Confusingly, for reasons lost in the mists of time three of the books appear in both treatises (NE 5-7 = EE 4-6). Although until the commentary of Aspasius in the second century AD the EE was apparently considered to be the definitive statement of Aristotle's views, since then the NE has taken priority (so much so that many scholarly treatments of Aristotelian ethics completely ignore the EE). Yet detailed stylometric and textual analyses conducted by Anthony Kenny from the 1960s to the 1990s indicate that the three "common books" go with the EE, not the NE. It also seems likely (though so far not yet proven) that the EE was written after the NE, during the last eight years of Aristotle's life.
If that's true, there are significant implications for Aristotelian interpretation. Although the differences between the NE and EE are not wide-ranging, on the question of the τέλος or goal of human living the differences are fairly stark: in book ten of the NE Aristotle argues that the highest goal is life of philosophical contemplation (which sounds rather Platonic), whereas in book eight of the EE he argues that the highest goal is a more balanced existence that includes family, friendships, social engagement, and excellence of character as well as theoretical inquiry.
This topic interests me along several dimensions, from the statistical analysis of Aristotle's works to the philosophical conclusions he settled on. I'm not sure I'll fully explore these matters while writing Complete Yourself, but I'm thinking about delving into them deeply later in life. I might even attempt to translate the Eudemian Ethics, since the NE has been translated plenty of times, most ably by Joe Sachs (yet even he missed some opportunities to get as close to the pagan Greek original as possible). This would be a big mountain to climb, but it's good to have high ambitions. :-)
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