As for the rational investigation of this question, we have discussed it at length in another place and have shown that what these pseudo-philosophers call “composition” – such as their claim that a thing is made up of existence and quiddity, or that species are composed of genera and differentiae – is, in the view of the overwhelming majority of sound minds, patently false.

In extramental reality there is nothing but an entity characterized by attributes; there is no self-subsisting existence alongside some other quiddity distinct from the very existent that subsists by itself, for example. One may, of course, intend by the word “quiddity” what the mind conceives, and by “existence” what is found in concrete reality; in that case the quiddity is indeed other than the existence, and one may then say, “This quiddity is distinct from this existence.”

The same applies to their statement that the human being existing outside the mind is composed of genus and differentia. The human found in reality – like every other existent – is simply an entity endowed with attributes. Yet the mind can conceive something compounded of “animal” and “rational,” just as it can conceive something compounded of “animal” and “laughing”; such composition is purely mental, not actual, and we have elaborated this point elsewhere.

It therefore becomes clear that what they regard as attributes internal to the quiddity, what they place outside it as necessary concomitants, and what they treat as the sum of the parts of the quiddity all, upon careful scrutiny, reduce to what is indicated by tadammun (inclusive implication), iltizam (necessary entailment), or mutabaqa (direct correspondence).