While I’m inclined to think that some of Aristotle’s “Works” are student lecture notes, still, those Basic Works are the culmination of Greek rational endeavor.
In his book After Virtue Alasdair MacIntyre writes:
Yet it is not of course just that Nietzsche’s moral philosophy is false if Aristotle’s is true and vice versa. In a much stronger sense Neitzsche’s moral philosophy is matched specifically against Aristotle’s by virtue of the historical role which each plays. For, as I argued earlier, it was because a moral tradition of which Aristotle’s thought was the intellectual core was repudiated during the transitions of the fiftheenth to seventeenth centuries that the Enlightenment project of discovering new rational secular foundations for morality had to be undertaken. And it was because that project failed, because the views advanced by its most intellectually powerful protagonists, and more especially by Kant, could not be sustained in the face of rational criticism that Nietzsche and all his extentialist and emotivist successors were able to mount their apparently successful critique of all previous morality. Hence the defensibility of the Nietzschean position turns in the end on the answer to the question: was it right in the first place to reject Aristotle? For if Aristotle’s position in ethics and politics – or something very like it – could be sustained, the whole Niethzschean enterprise would be pointless. This is because the power of Nietzsche’s position depends upon the truth of one central thesis: that all rational vindications of morality manifestly fail and that therefore belief in the tenets of morality needs to be explained in terms of a set of rationalization which conceal the fundamentally non-rational phenomena of the will. My own argument obliges me to agree with Nietzsche that the philosophers of the Enlightment never succeeded in providing grounds for doubting his central thesis; his epigrams are even deadlier than his extended arguments. But, if my earlier argument is correct, that failure itself was nothing other than an historical sequel to the rejection of the Aristotelian tradition. And thus the key question does indeed become: can Aristotle’s ethis, or something very like it, after all be vindicated? [p117]