Divinity and humanity in Aristotle's ethics

Aristotle wrote two major ethical works, the Nicomachean Ethics (NE) and Eudemian Ethics (EE), and the relationship between the two has long been a matter of scholarly controversy. To further complicate things, three chapters are printed verbatim in the middle of both works: NE V-VII = EE IV-VI. Without knowing where these so-called ‘Common Books’ properly belong, we cannot know even what constitutes the text of the NE or EE, let alone the relationships between them. The nearly universal consensus is that the Common Books were written as part of the early EE, then revised or replaced for the later NE, at which point the later version supplanted the EE originals even in the EE manuscripts. I argue here that this is likely incorrect: the Common Books do not belong in the NE at all. The NE defends a view where persons are identified with a single part of the soul that (i) is the seat of both theoretical and practical wisdom, and (ii) is divine in a way that makes human happiness the same kind of activity as the gods’ activity. The Common Books reject both these positions, as does the EE. This suggests that the Common Books are philosophically inconsistent with the NE; it is therefore probable the Common Books were neither written as a part of the NE nor revised for inclusion in it. I conclude by defending the results and methodology of this project from various objections, and show how the undisputed NE can still form a complete treatise even without the Common Books.