ESSENCE CANNOT BECOME A GENUS SO LONG AS IT REMAINS ONE.
Considering unity according to its essence, it seems to fuse and coincide with absolute Essence, for essence, so far as it trends towards unity, is a single essence; but in so far as it is posterior to unity, it becomes all things it can be, and becomes manifold. Now, so far as essence remains one and does not divide, it could not constitute a genus.
ELEMENTS OF ESSENCE CAN BE SAID TO BE ONE ONLY FIGURATIVELY.
10. In what sense, therefore, could each of the elements of essence be called "one"? In that it is something unitary, without being unity itself; for what is a "certain one" is already manifold. No species is "one" except figuratively[306]; for in itself it is manifold. It is in the same sense that, in this sense-world, we say that an army, or a choric ballet, constitute a unity. Not in such things is absolute unity; and therefore it may not be said that unity is something common. Neither does unity reside in essence itself, nor in the individual essences; therefore, it is not a genus. When a genus is predicated of something, it is impossible to predicate of the same thing contrary properties; but of each of the elements of universal essence it is possible to assert both unity and its opposite. Consequently (if we have called unity a genus), after having predicated of some essence unity as a genus, we would have affirmed, of the same essence, that unity was not a genus. Unity, therefore, could not be considered one of the primary genera; for essence is no more one than it is manifold. As to the other genera, none of them is one without being manifold; much less could unity be predicated of the secondary genera of which each is quite manifold. Besides, no genus, considered in its totality, is unitary; so that if unity were a genus, it would merely thereby cease being unity; for unity is not a number, and nevertheless it would become a number in becoming a genus. Of course, numbers include an alleged unity, as soon as we try to erect it into a genus, it is no longer a unity, in a strict sense. Among numbers unity is not applied to them as would have been a genus; of such unity it is merely said that it is among numbers, not that it is a genus; likewise, if unity were among the essences, it would not be there as genus of essence, nor of anything else, nor of all things. Again, just as the simple is the principle of the composite without being considered a genus in respect to it—then it would be simultaneously simple and composite—so, if one were considered to be a principle, it could not be a genus in respect to things subsumed under it; and therefore will be a genus neither for essence, nor for other (categories or things).
VARIOUS ARGUMENTS AGAINST UNITY AS A CATEGORY.
If unity were to be considered a genus, it could be that only in respect to the things of which each is said to be one;[309] as if, for instance, one should, from "being," deduce the unity contained within it. Unity would then be the genus of certain things; for just as essence is a genus, not in respect to all things, but in respect to those species that possess essence, so unity would be a genus in respect to the species that possess unity. This, however, is impossible; for things do not differ in respect to unity, as they do in respect to essence.
It might further be objected that if the same divisions which were applied to essence were applied to unity, and if essence be a genus because it divides itself, and manifests itself as the same in a number of things, why then should unity also not be a genus, since it appears in as many things as essence, and similarly divides itself? Mere recurrence of something in several essences is no proof it is a genus; whether in respect to the essences in which it occurs, or to others. Merely being common to several essences by no means constitutes a genus. No one will claim that a point is a genus for lines or for anything else, though points be found in all lines. As said, unity is found in every number, and nevertheless it is not a genus for any number, or for anything else. The formation of a genus demands that what is common to several things show specific differences, constituting species, and be predicated of what exists. But what are the specific differences within unity? What species does it form? If to this it be answered that it forms the same species as essence, then it blends with essence, and (unity) is (as said above), only another name for essence; and essence, as category, suffices.
GENUINE RELATIONS BETWEEN UNITY AND ESSENCE.
11. The questions here to be solved are, how unity subsists within essence, how they both divide, and in general how any genera divide; and whether their two divisions be identical, or different. To solve these questions, we shall first have to ask how in general any thing whatever is said to be one, and is one; then, if it can be said in the same sense that essence is one, in what sense this is said. Evidently, unity is not the same for everything. It cannot even be understood in the same sense in respect to sense-things, and intelligible things; not any more than essence is identical for these two order of (beings), or even for sense-things compared to each other. The idea of unity is not the same in reference to a choric ballet, an army, a vessel or a house; it is even less so in respect of one of these things, and when it deals with continuous objects. And nevertheless, by their unity all these things imitate the same archetype, some from far, some from near. Intelligence, surely, is assuredly that which most approaches absolute Unity; for although the soul already possess unity, Intelligence possesses it far more intensely; for it is the one essence.