Cursus Philosophicus Thomisticus, Secunda Pars Artis Logicae

This division has been accepted in the schools by the celebrated consensus of all; it divides the five predicables, namely, genus, species, difference, property, and accident. TWO QUESTIONS CAN BE RAISED to explain it. First: What is the subject divided by this division? Second: Do the dividing members exhaust that subject, so that the division is adequate?

As to the first, I say two things. First, the subject of this division is a univocally predicable universal. Second, it is the universal formally, that is, by reason of universality and predicability (for we are not counting these separately here), that is divided, not the nature underlying universality.

THE REASON FOR THE FIRST is that all the dividing members are predicable of many and not of only one. For what is predicable of only one is either an individual or predicated identically, not formally. Here, however, we are dealing neither with individuals nor with identical predication, but with formal predication, because the subject is the art of predication; predicating something of itself is not an artificial mode. Likewise, it must be predicable univocally, because although an analogate is predicated of many, it is not predicated simply and in one way, but partly in one way and partly in another. Hence it is not a universal without qualification, but in a qualified sense—that is, in a proportional mode—and so it is excluded from the universal without qualification that we are discussing here. Furthermore, only predicables are treated here insofar as they contribute to constituting the categories, which certainly consist of genus and difference, by which a species is constituted, to which a proper property and accidental predicates belong. An analogate constitutes none of these, and thus it does not per se belong to the predicables, just as it does not belong to the categories.

THE REASON FOR THE SECOND is that being predicable and universal is accidental to a nature. Therefore, a different mode of predication does not divide the nature itself as nature, but divides what is predicable insofar as it expresses an aptitude for predicating. Therefore, the division into the various modes of predicability must take as its formal subject divided the formal character of universality or predicability itself, not the nature that underlies it. Besides, the nature underlying universality is not anything definite and determinate; it can be something real or of reason, substance or accident. But the intention of universality itself is something definite and determinate, as an accident of reason with respect to the nature. Therefore, this division falls upon a definite and determinate subject by reason of that intention.

If you ask whether the subject divided is only the logical universal, as the relation of the universal, or also the metaphysical universal, as the foundation of this relation: the reply is that both are divided in a proportionate way. For a relation is not divided unless its foundation is divided; indeed, a relation is divided through its foundations. Therefore, if the mode of predication is different, there must also be a different mode of identification with the things of which it is predicated. Consequently, this difference must be taken not only according to the comparison and relation to inferiors as its terminus, but also according to the aptitude for being, that is, for being predicated together with inferiors; and consequently according to the abstraction that grounds this aptitude in a unity abstracted in this way and identifiable with inferiors in one way or another.

Concerning the SECOND QUESTION: This division is exact and adequate, and it exhausts every character of predicability.

THE REASON IS that the formal character of predication consists in the identity and connection of one extreme with another. Therefore, that division of predicability will be adequate which adequately divides the connection and identification of the extremes. Every identity or connection of extremes is either essential or accidental, intrinsic or extrinsic, necessary or contingent. If it is essential, it either expresses the whole and complete essence—that is, everything that contributes to the definition. If it expresses the complete character of the essence or quiddity, it is species. If it expresses a part, that part is either potential and contractible, or actual and contracting. If it is potential and contractible, it is genus, and is predicated in quid incompletely, because it expresses a quidditative part, namely, the first and substantial part, which stands beneath others and is determinable by them, rather than determining and, as it were, qualifying them. If it is an actual part, it is difference, because it is a predicate that acts, as it were, as an act determining and qualifying. If something does not belong essentially but accidentally—that is, does not enter into the constituents of the essence—it is either a predicate that proceeds from proper principles and has a necessary connection with them, and thus is a property; or it belongs through extrinsic and common principles, and thus is an accident. Since these divisions are made by members that are immediately and contradictorily opposed, they rightly and adequately divide the subject itself.

SOME, however, say that in the second predicable, species, the whole quiddity is not predicated, but only a part, because species is a part of an individual and not the whole individual; thus it is predicated in the same way as genus, namely, as a part.

But this is said improperly, because species expresses the whole definition, or the whole that is included in the definition—that is, what consists of genus and difference—and therefore expresses the whole essence of the thing. Hence, with respect to the essential constituents of any individual, species expresses not a part but the whole, even if it does not express the whole with respect to the mode that is singularity. For individuation adds nothing pertaining to nature or essence, but pertains to the mode of the nature. Thus species is the whole quiddity of an individual; for two individuals do not differ in essence, but in number and mode of being. It is therefore improper to deny that species predicates the whole, that is, everything that belongs integrally and completely to the essential constituents in the character of quiddity.

THE ARGUMENTS ARE ANSWERED.

First, one may object that there are many things predicated of many which are not contained in this division; therefore it is not adequate.

The antecedent is clear, first, in the analogate, which is predicated of many analogates and yet is neither genus nor species, much less difference, and so on. Likewise, a vague individual, such as “some human being,” “person,” or “supposit,” is predicated of many: Peter is called an individual and a person, and Paul likewise, and so on. Yet it is neither genus nor species, because genus and species abstract from individuals and predicate only the nature. Finally, existence, death, and similar predicates are neither predicated essentially, because they do not pertain to the quiddity of a thing, nor as a property, because they do not flow from intrinsic principles, nor as an accident, because they are not present and absent without the corruption of the subject. Therefore, they are not contained in any of these predicables.

The point is confirmed specifically by the way human nature and its higher predicates are predicated of the divine Word. For they are not predicated of God essentially, since they began to belong to him in time; nor contingently, as an accident, since the union of a human being to God is substantial and makes God truly and univocally a human being, just as Peter and Paul are, to whom human nature does not belong contingently; nor as a property, since it does not naturally flow from God's intrinsic principles, for otherwise it would have belonged to him from eternity. Therefore, there is a mode of predication that does not pertain to these five predicables.

THE REPLY: The antecedent is denied. As to the objection about the analogate, it was said above¹ that an analogate is not a universal without qualification, but by reduction, because it does not express a predicate that is simply one, but one that is partly one and partly diverse. The definition of a universal, however, is that it is one in many. Therefore, just as it falls short of the character of unity, so it falls short of the character of universality without qualification.

As to the second objection about a vague individual, we say that it is excluded from the character of a universal without qualification by nearly the same principle, because it expresses not only a nature but also a mode of being, which is individuation or personality, as St. Thomas teaches in Summa theologiae I, q. 30, art. 4. Hence it does not have one simple mode of predication, but is predicated in quid and in quale: in quid insofar as it expresses a nature, and in quale insofar as it expresses a mode of individuation, which lies outside the concept of the nature and depends on accidental conditions pertaining to the here and now. Thus it is not reduced to only one predicable, but to several, namely, the individual or essential predicable. A definition is likewise excluded from the character of a predicable without qualification, because it is a complex term and not a simple one; it is reduced, however, to the second predicable, because it is reduced to what it defines. For properly only species is defined, as is said in Metaphysics VII², because only species consists of genus and difference.

The reply to the third objection will be given in question 12, On Accident. For now it is enough to indicate that being present and absent without corruption of the subject means the same as without destruction of the quidditative concept. This is how the definition of accident is understood. Thus death and existence are accidents, because although they are not present or absent without physical corruption, which pertains to existence, they can be so without metaphysical corruption, which pertains to the quiddity of the subject to which they belong. The opposite occurs with a proper property: if its connection to the subject is destroyed, the essence is consequently destroyed.

To the confirmation, the reply is that some think that from the union of human nature to the Word there resulted new predicables, which they call assumptive, because they are said of God neither essentially nor accidentally, but substantially. St. Thomas, however, clearly holds in Summa theologiae III, q. 16, art. 1, that human nature is predicated after the Incarnation in the same way as of any other individual of that nature. Otherwise, that person would not be univocally a human being, if “human being” were not predicated essentially of him as it is of other individuals of that nature. On this see Cajetan there.

When it is said that it belongs to God accidentally and from a point in time to be a human being, the reply is that it belongs accidentally to God as subsisting in the divine nature to be a human being, and God became a human being in time. But for God as subsisting in human nature, and given the Incarnation, to be a human being is essential, because in this way he is an individual human being.

When it is objected, “Then he is a human being from eternity, because essential propositions are eternal,” the consequence is denied because the supposition varies. When one says, “God is a human being from eternity,” the term “God” is taken absolutely and gives an absolute sense; it is applied to God without any restriction and thus involves God insofar as he subsists in the divine nature. But it is said temporally of God as subsisting in the divine nature that he is a human being, and not from eternity. If, however, it is taken restrictively for God as subsisting in human nature, or for God incarnate, then the proposition is eternally true, taking “is” with respect to connection and predication, not with respect to existence. In these propositions, however, because of the danger of error, the proposition should not be conceded so absolutely, but with a restriction.

Second it is argued: There are two predicables into which all the others fit, namely, what is predicated essentially and what is predicated accidentally; therefore five are superfluous.

If you say that those two are genera of predicables and not the ultimate species into which they must be divided, the reply is: If the five predicables are the lowest species, more than five should be posited. For just as predication in quid is divided into predication of many differing in species, which is genus, and of many differing in number, which is species, so predication in quale essentially could be divided into what is predicated of many differing in species, namely, generic difference, and what is predicated of many differing in number, namely, specific difference. Likewise, genus can be divided into supreme and subordinate genus. And just as predicable is divided according to predication in quid and in quale, essentially and accidentally, why should it not also be divided according to predication separably and inseparably, intrinsically and extrinsically, possibly and impossibly, and other similar modes that constitute different species of predicability?

The point is confirmed because the Philosopher in Topics I, chapter 3³, names only four predicates, namely, genus, definition, property, and accident; therefore there will be just as many predicables, since they are related as predicates. But if the number of predicables is taken in relation to the categories, since there are ten modes of being, namely, ten categories, there will be just as many predicables, because the mode of predicating follows the mode of being.

THE REPLY is the solution given to the argument. To the first reply, we say that being predicated of many differing in species, if taken precisely, does not formally distinguish predicables, since the same genus is predicated of diverse species and individuals, and the same is true of a difference and a generic property. The formal distinction between genus and species is that genus is predicated in quid incompletely, that is, it does not predicate the complete quiddity but a part of it, whereas species is predicated in quid completely, that is, it predicates the complete quiddity. But the complete character of quiddity can be predicated only of many individuals. We say that it predicates the complete quiddity, not because it expresses the whole found in an individual, including the mode of singularity, but the whole that pertains to quiddity in individuals. Difference, whether generic or specific, always predicates an essential part, not the whole; hence it does not differ in its mode of predicating, but in the material thing it predicates. Supreme and subordinate genus likewise have the same mode of predicating, namely, a quidditative part, not the whole quiddity, although one quidditative part is more universal and higher than another. For this is accidental to the formal mode of predicating in the manner of the art of predicating in quid, about which we will speak at greater length in the questions on genus and difference.

To the final objection, we say that not all modes vary the character of predicability per se, but only those that per se vary the mode of identification and connection of the extremes according to the character of one in many, as belonging essentially or accidentally, by way of quid or quale. The remaining modes, which do not per se vary this mode of connection and identity, do not constitute different predicables unless they are reduced to these modes, “essentially” and “accidentally.” Thus “intrinsically” is reduced to them, as in some cases are “separably” and “inseparably”: the separable is an accident, and the inseparable a property. When, however, these are found only within the accidental genus, they do not per se vary the character of one thing's predicability of many.

To the confirmation, the reply is that in that passage Aristotle is not numbering the modes by which universals are predicated of inferiors, since he also numbers definition, which is a complex quid. Rather, he numbers predicates from which topics of argument are drawn for various questions. Because the same argument is taken from species and from its ultimate difference (for genus expresses a more indeterminate character), Aristotle therefore treated species and difference together under the single name “definition,” for the sake of brevity.

To the added objection concerning the number of categories, the reply is that the modes of predicables do not follow the mode of being absolutely and according to participation in being, but the comparative mode by which inferiors are connected with superiors. In sum: Categories are distinguished in the case of accidents according to different modes of participating in substance, and substance itself by the fact that it has being per se. Predicables, however, are distinguished according to the different order of the universal to inferiors.