In De ente et essentia D. Thomae Aquinatis commentaria

Whether matter is the principle of individuation.

Concerning this part, it is asked whether matter is the principle of individuation. In this question there are six matters to be handled. First, the title will be explained; second, Scotus’s opinion will be set forth; third, it will be refuted; fourth, the opinion of St. Thomas will be set forth; fifth, arguments will be made against it; sixth, the arguments on the contrary will be answered. As to the first, note that when the principle of individuation is discussed, since “individual” signifies two things, namely, what is undivided in itself and what is distinct from others, nothing else is being asked except by what specific nature is first made incommunicable, so that it is repugnant to it to be communicated to many, as it is communicated to inferiors by superiors, and by what this individual is first really distinguished from others of the same species. Therefore two things concurrent in individuation are asked: namely, by what specific nature is first made incommunicable, and by what it is first really distinguished from others of the same species. And observe carefully the individual parts of the title which we have explained, since I find some people err in this matter. For here we are dealing with incommunicability opposed to real communication, and not with incommunicability opposed to communication of form; no one doubts that the latter belongs first to matter. Likewise, here we are dealing with the real distinction of individuals under the same species, which exists only among real beings, and not with the distinction by which living Socrates and dead Plato are distinguished. Always observing that now we speak only of the individuation of material substances. So much for the first.

SCOTUS’S PROPOSITION.

Not matter, nor form, nor the composite, but an individual property, haecceity, is the principle of individuation.

As to the second, Scotus, in II Sentences, distinction III, question vi, holds that specific nature is individuated through something positive contracting it through itself and making one with it: so that this positive thing is neither matter, nor form, nor the composite, but is the mode of all things or the ultimate reality of matter, form, and composite, really identical with them; and thus he gives this conclusion concerning the principle of individuation: The principle of individuation is not matter, nor form, nor quantity, but an individual property, namely, haecceity. I now omit the proofs of this conclusion concerning the first three parts, to be brought forward later insofar as they pertain to the point at issue. For the fourth he argues as follows: unity follows being, proportionally speaking; for in the same way a thing is being and one; therefore ultimate unity simply, namely numerical or individual unity, follows individual being. But it is clear that this individual being is none of the things which are actually in the species, nor any accident, since all accidents are posterior; therefore it is an individual property, constitutive of individuals. And he argues as follows: that to which numerical unity first follows is the principle of individuation: that property or haecceity is what numerical unity first follows; therefore haecceity is the principle of individuation. The major is clear, because unity proportionally follows being. The minor is proved because numerical unity does not follow quiddity, as is evident, nor any accident, since it precedes the whole genus of accidents. Secondly, as follows: every difference of things differing is reduced to things first diverse, otherwise there would be no terminus among things differing; but individuals properly differ; therefore their difference is reduced to things first diverse. These are neither their natures, nor privations, nor any accidents; therefore they are haecceities. The proof of this last assumption concerning the third part is as follows: if the difference of individuals is reduced to an accident, it is reduced chiefly to quantity; but this is not so. This is clear as follows: let it be asked by what this quantity and that quantity differ; not through themselves, for thus they would be specifically distinct; therefore through something else, for example, places. But this cannot be, because either they are distinguished by place, which is a special category, and this is not so, because place is posterior to quantity, or by place, which is a difference of quantity, and this is not so, because it must be asked by what those places are distinguished: either through themselves, and this cannot be said, since they are not these places through themselves, or through something else, and so on to infinity. And therefore, since place, which is a difference of quantity, is integrated from the continuity and permanence of parts, it is the same to say that this quantity differs from that on account of another place, and that this quantity differs from that quantity through itself. Thirdly, as follows: that which through its whole self first constitutes some singular in its singular being and in the unity consequent upon such being, through its whole self first repugns division contrary to that unity, and consequently is the principle of individuation; but only an individual property or haecceity is of this kind; therefore, and so forth. The major is clear from the terms, and the minor is proved in the same way as above. So much for the second. As to the third, an argument is made against Scotus’s opinion in four ways. First, as follows: every singular act presupposes a singular potency which it actualizes; but haecceity is a singular act; therefore it presupposes a singular potency which it actualizes; but that potency is the nature or is in the nature of the individual; therefore the nature of the individual is singular before the arrival of haecceity, and thus haecceity is not the principle of individuation. All the propositions assumed are Scotus’s in this matter, including the major, which nevertheless is proved from the teaching of Aristotle, Physics II, text XXxvul, where he teaches the comparisons of causes; hence, just as a particular form presupposes particular matter, so act presupposes potency. If it is said that this is true where act and potency are really distinct, because according to Scotus, when two things are really united, they retain by nature the same order which they would have if they were really distinct: since therefore a singular act, if it were really distinct, would by its nature presuppose a singular potency, it is necessary that it should now require the same thing, since the order remains the same. Secondly, as follows: those things which are principles of individuation are through themselves first diverse; the haecceities of Socrates and Plato are not of this kind; therefore. The major is Scotus’s; the minor is proved as follows: that which agrees more with one than with another is not first diverse from the one with which it agrees more; but Plato’s haecceity agrees more with Socrates’ haecceity than with the haecceity of whiteness; therefore the haecceities of Plato and Socrates are not first diverse. The major of the prosyllogism is clear from the terms: for what is first diverse from another does not agree with it. The minor is proved in two ways: first, because the haecceities of Socrates and Plato agree in species, while the haecceities of Socrates and whiteness differ in genus; second, because those things agree more which are more alike, and those are more alike which are more comparable; but the haecceities of Socrates and Plato are more comparable than the haecceities of Socrates and whiteness, just as universally things of the same category are more comparable than things of different categories. Third, as follows: that which agrees with and repugns to another individual of the same species necessarily presupposes their distinction: an individual property, for example, Socrateity, agrees with Socrates and repugns to Plato, an individual of the same species; therefore an individual property presupposes the distinction of Socrates from Plato, and thus an individual property is not that by which Socrates is first distinguished from Plato. The conclusion is false according to Scotus; the reasoning is sound; therefore one of the premises is false; but both are his; therefore he is altogether proved false. The major is found in Scotus in every question II; the minor, however, is his conclusion which we are now attacking. Fourth, I show that this position contradicts the Peripatetics, Aristotle, and the Commentator. For in Metaphysics XII, text XLI, this consequence is made: the first heaven, that is, the first principle, is one in species and many in number; therefore it has matter; which consequence would be null if an individual property were posited as distinguishing individuals of the same species. But that Scotus’s gloss, understanding “matter” as an individual property, destroys the text, is clear from the Commentator there saying: everything which is one in species and many in number has matter; but it has already been declared that the principle of heaven has no matter; from these words it is clear that he is speaking of that matter which he declared not to be in the first principle. It also clearly appears that in text XXX he expressly declared the mover of heaven not to have matter either for place or for being, and made no mention of an individual property. The fiction of that gloss also appears from Metaphysics III, text I, where it is said that every multitude is either of things differing according to form or according to quantity, which same thing you have in the Commentator on Physics I, text VI. Nor is the gloss of Antonius Trombeta to be admitted, that it is understood concomitantly. For “according to” must be held in the same way and uniformly in the first member and in the second; in the first it denotes causality; therefore also in the other. It can also be detected that this new invention concerning haecceities is a pure fiction from On the Heavens I, texts XC and XCII, where Aristotle and the Commentator assign the unity and plurality of individuals in the same species, in material things, to matter alone. So much for the third.

CONCLUSION Designated matter is through itself the intrinsic principle of individuation, but not something aggregated from matter and quantity.

As to the fourth point, St. Thomas’s opinion, stated by him here and in many other places, is that designated matter is the principle of individuation. Concerning this conclusion, it should be noted that Thomists differ among themselves and agree. They all agree in this, that two things must concur in individuation: matter and quantity. They differ, however, because some hold that the aggregate of matter and quantity is the intrinsic principle of individuation: matter giving incommunicability, or indistinction in itself; quantity giving distinction from other things; and they call such an aggregate designated matter. Others, however, think much better, saying that the intrinsic principle of individuation, both as regards incommunicability and as regards distinction from others, is designated matter, not quantified matter, or an aggregate of matter and quantity. Since this, in my judgment, is the true doctrine of St. Thomas, as will be shown, we therefore wish to explain and defend it: first explaining what designated matter signifies; second excluding the first Thomist explanation; third proving the intended conclusion. Designated matter is nothing other than matter capable of this quantity, but not of that one; for this matter is an intrinsic part of Socrates, belonging to his definition if he were defined. For one must imagine that a particular agent—for example, this seed—continually appropriates matter for introducing a form in such a way that, just as human seed appropriates matter for a human soul, so this seed appropriates it for this soul. Hence, when at the first instant of Socrates’ generation—which is Socrates’ first being, the first non-being of the preceding form, and, in the first order of nature, of the accidents—a particular composite comes to be, and then, in natural order, all the accidents follow in that prior according to nature in which the particular composite terminates generation through itself and first, the matter that is its intrinsic part, namely Socrates’ matter, is so appropriated to Socrates by the particular agent that it is capable of no quantity other than the one Socrates determines for himself. For the magnitude and growth of everything constituted by nature are determined, as is said in On the Soul II, from Commentary XLI; and such matter is called designated matter. Designated matter therefore adds nothing to matter except the capacity for this quantity, but not for that one. The capacity of matter with respect to this quantity is nothing other than the receptive potency for this quantity, but not for that one; the receptive potency, however, says nothing really distinct in the direct signification, but adds to matter something real distinct only according to reason. Just as proper matter adds nothing really distinct from matter itself, yet says something real in matter which matter according to itself does not explain—for designated matter is definable only through this quantity, if it were defined—so proper potency is defined only through its proper act, as is said in Physics III, text X. Matter according to itself does not require this quantity in its definition. Hence the proper matter of an individual, designated matter, and matter under determinate dimensions signify the same thing. Therefore St. Thomas did not say “matter with determinate dimensions,” but “under determinate dimensions”; and elsewhere he says that just as matter, in relation to general forms—for example, the total and partial form—distinguishes heavenly bodies generically from lower bodies, so matter, in relation to this or that quantity, distinguishes things in material realities numerically. Designated matter therefore does not signify an aggregate of matter and quantity, but signifies matter directly and quantity obliquely; just as the potency of matter signifies matter directly and, obliquely, the act to which it is ordered, since it is definable only through that act. Thus it is clear what designated matter signifies. That the other Thomists do not explain it suitably is shown as follows: the principle that distinguishes an individual from its species and from another individual of the same species is the same; but matter not quantified, rather matter designated in the manner explained above, is the intrinsically distinguishing principle of an individual from its species; therefore it is not quantified matter, but designated matter, that is the intrinsic distinguishing principle of an individual from another individual of the same species. They concede the minor, and it is expressly St. Thomas’s in the treatise called On the Principle of Individuation—which, according to the truth and its ancient title, is called On Cognitive Powers, as it is held in the Supreme Pontiff’s library, where alone I have seen that treatise complete; for the one commonly possessed is truncated. The major, however, seems capable of being denied by the insolent only in words. For we universally see this to be true: whenever something common is divided into several subjective parts, the lower things differ from one another and from the superior through the same thing; thus man differs from animal and from lion through the same thing, namely his proper difference. Hence Porphyry gives three acts to difference: dividing the superior, constituting the inferior, and distinguishing the constituted thing from the superior and from its other coordinate members. This conclusion is therefore proved in the manner explained above, namely: designated matter is the intrinsic principle of individuation. That is the intrinsic principle of individuation to which it first belongs not to be communicated to many in the way a universal is communicated to a particular; but designated matter is that to which it first belongs not to be communicated as a universal to a particular; therefore, and so on. The major is conceded by all; the minor is proved.