Plato and Aristotle - but it would seem Aristotle even more, from the overall vibes I get from these writers - identify the human form and essence (are these the same thing?) as the rational or intellectual capacity, the ability to think in terms of universals or concepts (are these the same thing?). Plato would speak in terms of the proper ordering of the human soul with the rational part in charge, which goes quite a way in its own right to get the program just right, while Aristotle makes the perfection of the rational part, that very essence of man, the ultimate normative standard by which to characterize a flourishing life. So if philosophers are really into the whole "perfecting the rational part of us" idea, why wouldn't that make them specifically Aristotelians as well? In ethics, to be an Aristotelian is to endorse the idea, in some fashion or other, that the good life, the most perfect life attainable to us, is defined ultimately by reference to how we use our specifically rational activity. (Not coincidentally, this is the faculty under direct control and review by human agents themselves; this is the phenomenon referred to as free will.)
Ayn Rand, who was rather quite comfortable with referring to herself as an Aristotelian, while dismissing almost wholesale the rest of the history of philosophy (Aquinas being a rare, standout exception), put this idea in the following terms:
Man has a single basic choice: to think or not, and that is the gauge of his virtue. Moral perfection is an unbreached rationality—not the degree of your intelligence, but the full and relentless use of your mind, not the extent of your knowledge, but the acceptance of reason as an absolute.
This looks like a statement that every philosopher could, would, and should endorse. But how would it not make them Aristotelians (and, if they do their homework, Randians), all of them? Kantian and utilitarian ethics don't seem to express this idea in a clear-cut way - certainly not the utilitarian one, which focuses our attention upon to good experiences as the primary criterion of the good, while Kant does home in on our rational/intellectual agency as ethically fundamental and meriting respect, and states that the only thing good without qualification is a good will, but how about the Aristotelian idea that our most ethically perfect and most flourishing life (are these the same thing?) must contain in every activity some form or other of intellectual perfection. Isn't perfecting our intellectual capacity the best way we could express and enact our good/better/best wills, in any case? Good intentions are nice, but what if we perfect the science of improving people's lives through the perfection of our epistemological (volitional-cognitive) practices, then how much more fruitful would our intentions be? And how about if we take a giant leap for mankind in that process by spreading philosophical learning far and wide, including for children? And this education, pursued with optimal rigor, will lead to Aristotelian intellectual perfectionism as the most basic normative principle for living, correct?
If Aristotelians are better and more homed in on the intellectual-perfectionist essential here than philosophers of other traditions have been, this would be evidence for a thesis that Aristotelianism is a better way of doing philosophy itself than the other traditions are. To get thorough/complete/perfectionist on this we would need to do a rank-ordering in terms of better-thinking/living fruits yielded. Anyway, all activities that characterize human flourishing, Aristotelian-style, involve inter alia the perfection of the intellectual capacity, as like the form of human flourishing to whatever is the content of the activity. (Not only does this conception of ethics and eudaimonic activity have something of an aesthetic appeal to it, but it sounds distinctively Aristotelian in both the form of framing it and and in content. ^_^ ) Stated another way: human flourishing or eudaimonia, Aristotelian-style, is thoughtful or intelligent living.
My view of Aristotle in relation to the rest of the history of philosophy is something as follows: You can only hope to match him but not exceed him. He's the first to discover and fully implement a program of intellectual perfectionism (a maximally sprawling research program in his case, as full-time philosopher by profession) and quite self-consciously so. (So why wasn't, say, Bertrand Russell an avowed Aristotelian? How could his shoddy treatment of Aristotle in his History of Western Philosophy be at such variance with that of a Kenny, Cooper, Irwin, Barnes, Shields, et al? Assuredly more intellectual perfection needs to happen for everyone to get on the same page about the A-man.)
