the contingent—something other than these shared meanings. He thus has an aspect of commonality and an aspect of distinction; and this, according to them, is an impossible “composition.” If this composition entails the nonexistence of the necessarily existent, then the existence of the One necessarily existent in His own right entails His nonexistence. This is contradictory. This “compelling demonstration” thus establishes that their argument is internally contradictory, just as it has been established that, on their own principles, it is countered by what they themselves affirm.

As for the answer that resolves the difficulty, we say:

“Composition,” as understood by human reason and in human language, is the composition of an existing thing from parts distinguishable from one another. This is the composition of a body from its parts, such as a human being’s composition from organs and humours, a garment’s composition from its parts, or a drink’s composition from its ingredients. It makes no difference whether one part is distinct from the other, as a hand is distinct from a foot, or diffused throughout it, as bile is diffused in blood and water in milk.

The “logicians,” however, speak of species as composed of genus and differentia, as a human being is composed of animality and rationality: that is, composed of what it shares with the other species and what distinguishes it from other species. They also divide attributes into the “essential,” from which essences are composed—namely, genus and differentia—and the “accidental,” namely, the common accident and the distinctive property. The essence composed of the shared and distinguishing elements is then the “species.”

We say: this “composition” is a mental construct with no existence outside the mind, just as the “essence of the species,” insofar as it is universal, has no existence outside the mind. Rather, the very