You might think of Aristotle as a very systematic philosopher. His treatises are for the most part each devoted to one of a range of themes which are still regarded as though they were departments of philosophy: ethics, philosophy of nature, logic, metaphysics, to name the big ones. So you might expect that he would present in each of these treatises a set of doctrines, along with some arguments for them. You might think that it would be pretty easy to separate the doctrines from the arguments and walk away with the "Aristotelian system" in your back pocket. Or you might not, dear reader, I don't know you that well. But I have always tended to expect this systematic structure in Aristotle, and I am even now surprised whenever I find in Aristotle's writings show more sketches toward a way of thinking than finished representations.
Well, that was supposed to be a preface to some remarks about the first pages of the Nicomachean Ethics, but that's all I can do today. I owe you.