It may be doubted, perhaps, whether this attempt at explaining the real, individual “manifoldness” of what is “one” for intellect, _i.e._ the universal, throws any real light upon the problem. No doubt, every element or factor which is grasped by intellect in its analysis of reality—matter, form, substance, accident, quantity, nay, even “individuality” itself—is apprehended as abstract and universal; and if we hold the doctrine of Moderate Realism, that the intellect in apprehending the universal attains to reality, and not merely to a logical figment of its own creation, the problem of relating intelligibly the reality which is “one” for intellect with the same reality as manifestly “manifold” in its concrete realizations for sense, is a genuine philosophical problem. To say that what individuates any real essence or nature, what deprives it of the “oneness” and “universality” which it has for intellect, what makes it “this,” “that,” or “the other” incommunicable individual, must be conceived to be simply the whole essential reality of that nature itself—leaves us still in ignorance as to why such a nature, which is really “one” for intellect, can be really “manifold” in its actualizations for sense experience. The reason why the nature which is one and universal for abstract thought, and which is undoubtedly not a logical entity but a reality capable of actual existence, can be actualized as a manifold of distinct individuals, must be sought, we are inclined to think, in the relation of this nature to a material principle in alliance with quantity which is the source of all purely numerical, “space and time” distinctions. 33. INDIVIDUATION OF ACCIDENTS.—The rôle of quantity in the Thomistic theory of individuation suggests the question: How are accidents themselves individuated? We have referred already (29, _n._) to the view that they are individuated by the individual subjects or substances in which they inhere. If we distinguish again between what _reveals_ individuality and what _constitutes it_, there can be no doubt that when accidents of the same kind are found in individually distinct subjects what reveals the numerical distinction between the former is the fact that they are found inhering in the latter. So, also, distinction of individual substances is the _extrinsic_, _genetic_, or _causal_ principle of the numerical distinction between similar accidents arising in these substances. But when the same kind of accident recurs successively in the same individual substance—as, for example, when a man performs repeated acts of the same kind—what reveals the numerical or individual distinction between these latter cannot be the individual substance, for it is one and the same, but rather the _time_ distinction between the accidents themselves.