if anything is kalon besides what is kalon simply it is kalon only because it takes part in what is kalon simply; and this applies to everything. Do you agree to this view of cause?
Kalon (K) might be best translated as good but I leave it untranslated here to draw attention to the fact that it is not good as opposed to beautiful or noble, or even as opposed to true, but as a general name for what all these have in common. In this sense, when Saint Thomas says in the Fourth Way that some things are “more or less good, true and noble, and such like”, his “and such like” is a gesture at the K. The K is, however, opposed to what is K because of its color, shape, size, etc. (100c-d). In other words, the doctrine he is opposing is Aristotle’s familiar one:
The term ‘good’ is used both in the category of substance and in that of quality and in that of relation, and that which is per se, i.e. substance, is prior in nature to the relative (for the latter is like an off shoot and accident of being); so that there could not be a common Idea set over all these goods.
Nic Eth. I.6
So both Aristotle and Plato agree that the genera are other than the K, but Plato reads this otherness as requiring a K itself while Aristotle takes this as just a logical abstraction from the hard reality of multiple genera.
The K transcends genera, but we miss the point when we take this as meaning that it is more general. The relevant opposition between the K and the generic is not between the more and less general but between what is considered as just itself and what is considered in combination with something else. A genus is not just a universal but a universal that is apt for differences. The dispute between Aristotle and Plato is therefore what role the composition of various ideas or rationes plays in an account of the real. For Plato, it is nonsense to say that a thing could only exist in combination with what is other than itself. Aristotle never denies this in so many words – it seems to involve a sort of metaphysical dialectic that he generally avoided. Aristotle seems to lean towards an empirical approach to things that takes the reality of genera for granted. But this doesn’t go quite far enough, since the question is not whether the genera are real but whether they are exhaustive, and that everything is such that something other than itself has to enter into its complete description.