In De ente et essentia D. Thomae Aquinatis commentaria

Whether nature taken absolutely has unity or plurality.

The second doubt concerns St. Thomas’s statement in the text, in assigning the second difference, where it is said that nature taken absolutely has neither unity nor plurality.

For this seems impossible, since what is not one cannot be defined, as is said in Metaphysics VII, text XII, indeed cannot be understood, as is held in Metaphysics VI, commentary X. And if it is granted that nature absolutely has unity, it is not easy to say what sort of unity it is: for it is neither numerical, as has been explained, nor specific nor generic, since these are made by the intellect, nor analogical, as is evident in itself—for man is not one analogically. Nor will anyone easily say whether that unity is real or not.

For clarity about this doubt, five things must be done. First, what any unity is must be seen. Second, whence unity has reality. Third, how any unity is outside the soul. Fourth, the doubt raised must be answered. Fifth, certain objections must be excluded.

Concerning the first, it must be known that, since one adds nothing to being except the privation of division—so that one is nothing other than undivided being, as is said in Metaphysics IV, text III—any unity is nothing other than the indivision of a thing. And since every privation is known through its habit, unity, which signifies indivision, must be known from the nature of the division it privates, and its multiplicity must correspond to the multiplicity of division.

Division, then, is twofold. One is material, caused by principles of individuation; the other is formal, made through essential principles. The latter has a range: one kind proceeds through proper essential principles, another through common essential principles. This too has a range, according as common essential principles are more or less common. For example, between Socrates and Plato there is numerical, not formal, division, because their distinction is caused not by essential but by individual principles. Between Socrates and this lion, supposing lion and man to be under the same first genus, there is formal division through proper essential principles, namely through the ultimate differences alone. Between Socrates and this plant there is a greater formal division, through essential principles common to Socrates and many other species, namely sensible and insensible. Between Socrates and this stone there is still greater formal division, through more common principles, namely animate and inanimate. Thus, ascending continually, formal division increases, so that between Socrates and this whiteness there is the greatest formal division, through proper and most common essential principles, namely substantial and dispositional modes, constitutive of the modes of being in the categories.

The same must be said in every respect of unity. Unity is twofold: numerical and formal. Numerical unity is considered according to the privation of numerical division. Formal unity is considered according to the privation of formal division, and this has a range. One kind privates every formal division causable through proper and common principles; this is formal unity simply. Another privates formal division not simply but in a determinate way, namely division causable through common principles; this is formal unity in a qualified sense, and it ranges according as the privated division is causable through more or less common essential principles. Thus Socrates is numerically one because he is not divided in himself by material differences. Man is formally one simply because he does not admit any formal division. Animal is formally one insofar as it does not admit division through sensible and insensible, but it is not one simply, since it admits division through rational and irrational. Body is less formally one: it is one because it is not divided in itself into corporeal and incorporeal, but it is less one because it admits the greater formal division into animate and inanimate. Being is least one: it is one insofar as it is not proportionally divided in itself, but least one insofar as it tolerates such formal diversity together with its unity. From this the first point is clear: any unity is indivision, and such unity is such indivision, that is, the privation of division. Thus to say “Socrates is numerically one” is to say “Socrates is a being lacking numerical division”; and “man is formally one” is to say “man is a being lacking formal division.” This concludes the first point.

Concerning the second, it must be known that real being is understood in two ways: first, as distinguished from being fabricated by the intellect; second, as distinguished from what does not actually exist. In the first way every categorical thing is real being, whether it exists or not. In the second way only what really exists outside its causes is real being. And since this is properly real being according to St. Thomas, who says in Questions on the Power of God, question III, article 5, ad 2, that a thing before it exists is nothing—and this agrees with Aristotle in the Categories, who says that when the first substances are destroyed nothing can remain—unity, like everything else, properly has reality insofar as it actually exists outside the soul and its causes.

Concerning the third, I propose three propositions. The first is: every unity mentioned above, both numerical and formal, exists outside the soul. The second is: no common unity exists outside the soul in nature in several supposits distinct in supposit. The third is: every formal unity existing outside the soul is really multiplied when the things themselves are multiplied. The first proposition is so evident that no sane person can deny it. In Socrates, apart from every operation of the intellect, both unities appear. For he lacks in himself numerical and formal division causable through proper and common principles, and thus has numerical and formal indivision. Hence in Socrates there is not merely numerical unity, but a plurality of formal unities according to the multitude of quidditative predicates. And just as not only Socrates’s individuality exists outside the soul, but each of his quidditative predicates, so not only numerical unity but each of his formal unities must be said to exist outside the soul.

To understand the second, it must be noted that a thing can be understood as common outside the soul in two ways: positively or negatively. A thing is positively common when it remains undivided while found in several supposits distinct in supposit. It is negatively common when it is proper to no supposit. In the first way, no one rightly asserts that a common thing exists outside the soul except the divine essence, according to the Christian faith. In the second way some seem to posit a thing common outside the soul; we shall speak of them below. Since this seems foreign to truth, I prove the second proposition in two ways.

First: no thing requiring a quiddity to be found outside the soul in isolation exists in nature; but a common unity outside the soul in several supposits distinct in supposit is a thing requiring a quiddity to be found outside the soul in isolation; therefore no such common unity exists in nature. The major is proved thus: nothing requiring something impossible for its existence is found; but a quiddity’s being found alone outside the soul is impossible, since it must be in some supposit; therefore what requires it to be found alone never exists in nature. The minor is proved thus: what requires a quiddity not proper to any supposit outside the soul requires it to exist alone; but a common unity outside the soul in several supposits distinct in supposit requires a quiddity not proper to any supposit; therefore it requires a quiddity to be found alone in nature. The premises are evident from the terms. The major is so because a quiddity not proper to any supposit is necessarily alone: if it is not alone, it is in some supposit, and if it is in some supposit, it is proper to that supposit. The minor is clear because common and proper are opposites: common includes the negation of proper, and conversely. As soon as a thing is appropriated to someone, it ceases to be negatively common, because it lacks the negation of appropriation; and as soon as it is negatively common, it is not appropriated, because it has that negation. Thus the opposite of the predicate entails the opposite of the subject in both premises.

Moreover, I prove it a second way: every thing existing in nature is a particular thing; no common unity outside the soul in several supposits distinct in supposit is a particular thing; therefore no such unity exists in nature. The major is known from the common Peripatetic opinion. The minor is proved thus: every particular thing is proper to one supposit, otherwise it would not be particular; but no common unity in several distinct supposits is proper to one supposit, as is evident from the terms; therefore no such unity is particular.

The third proposition is proved thus: whenever two things are really and convertibly the same, when one is really multiplied the other is multiplied also; but one thing and one are really convertibly the same; therefore when a thing is really multiplied its unity is really multiplied. But numerical plurality is real; therefore when a thing is numerically multiplied its unity is multiplied likewise. Hence in Socrates and Plato there are two corporeities, animalities, and humanities; so there are two formal unities following corporeity, two following animality, and two following humanity. For the number of formal unities in each individual must correspond to the number of essential predicates. Just as each quidditative predicate gives some being, so it must give some unity; for one and being are the same, as is said in Metaphysics IV, text III.

From this the third point is clear: unities have being outside the soul because they are not common but particularized and numerically multiplied according to the number of the individuals of which they are unities.

Concerning the fourth, I say that nature taken absolutely has a certain unity, as the argument brought forward, which is St. Thomas’s in his treatise On the Nature of the Genus, chapter VII, effectively concludes.

When it is asked whether that unity is numerical or specific, I say that it is formal unity, different from numerical unity, just as formal division differs from material division. Nor is that formal unity specifically or generically formal; rather, it is the foundation of specific and generic unity. For these unities are made formally by the intellect, whereas that unity precedes every act of the intellect. What is said in the text—that nature taken absolutely is neither one nor many—is to be understood of numerical unity and plurality.

As to the added doubt, whether this unity is real or not, I say that in itself it is real in the first of the senses we set out above, taking real being as nature itself is taken absolutely. And just as nature according to its being in singulars is real being in the second sense, so that unity, which always accompanies nature in particulars, is truly and properly posited as real. The judgment concerning nature and its unity is the same. This concludes the fourth point.

Concerning the fifth, two proper doubts arise. The first concerns the second proposition, in which it was said that there is no common unity outside the soul.

The second concerns what was just said: in what respect formal unity is different from numerical unity existing in Socrates.

Against the first, one objects thus. Whatever supposits distinct in supposit are formally one outside the soul have some unity common to them outside the soul; Socrates and Plato are formally one outside the soul; therefore Socrates and Plato have some unity common to them outside the soul. The major seems evident because, if supposits distinct in supposit are one, they are not distinguished in that in which they are one; thus that one is common to both outside the soul, by which they are one.

Moreover, humanity in Socrates, as far as it is of itself, is not determined to Socrates or Plato; therefore the formal unity of humanity in Socrates, as far as it is of itself, is negatively common to Socrates and Plato. The consequence is clear, since formal unity too, as far as it is of itself, is not determined to Socrates and Plato. The antecedent is evident in itself: therefore some unity common negatively to several supposits distinct in supposit is given outside the soul.

Concerning the second doubt, it seems that there is a real difference between formal and numerical unity existing in Socrates. For whenever the habits of privations are really distinct, the privations themselves are also really distinct; thus, since sight and hearing are really distinct, blindness and deafness also really differ. But the habits of formal and numerical unity are really distinct; therefore, and so forth. This is clear because formal division and numerical division are so distinct that in things separated from matter formal division is found without numerical division, while in these lower things individuals of the same species have numerical division without formal division.

To anyone considering the contrary arguments, however, it will appear that the difference is only one of reason. For as formal nature is related to individual nature, so formal unity is related to numerical unity; but nature taken formally is the same as nature taken numerically, and differs from it only in reason; therefore formal unity is really the same as numerical unity, and differs from it only in reason.

For resolving the first doubt, note that two things distinct in supposit can be formally one in two ways. In one way, the two are united in something outside the soul common to both and undivided in each. I find no example of this in nature except, as was said, the Trinity according to the Christian faith. In the other way, the two have a mutual negation of formal division between them. This is found in all individuals of the same species. For Socrates, with no intellect considering, has this negation: he is not formally divided from Plato; and Plato likewise is not formally divided from Socrates. Since being formally one requires nothing other than being formally indistinct, it is simply true that Socrates and Plato are formally one outside the soul. The argument therefore commits the fallacy of consequent, affirmatively passing from a superior to its inferior. Being formally one is superior both to having something common and undivided in them outside the soul and to having two natures with a mutual negation of formal division.

One must not imagine that Socrates and Plato are formally one because they agree in something in which they are not distinguished outside the soul, but because each enjoys a negation of formal division from the other. For formal one is nothing other than not formally divided. What we say of simple formal unity between Socrates and Plato should be understood of formal unity in a qualified sense between Socrates and this lion, this stone, and this intelligence. Just as Socrates and Plato, because they have two natures between which no formal division falls, are therefore simply formally indistinct outside the soul, so, because no formal division of the kind naturally caused by sensible and insensible falls between Socrates’s nature and this lion’s, Socrates and this lion are formally indistinct in a qualified sense. Likewise, because between Socrates and this stone there is no formal division through corporeal and incorporeal, Socrates and this stone are formally indistinct in a qualified sense. And because between Socrates and Gabriel there is no formal division of the kind naturally caused by the modes of being, namely in itself and in another, Socrates and Gabriel are formally indistinct in a qualified sense, and consequently are formally one without any operation of the intellect. For it has already often been said that one signifies the same as undivided being.

To the second I say that it is one thing to say, “Human nature existing outside the soul in itself is negatively common to several, or negatively indifferent,” and another to say, “Human nature existing outside the soul is negatively common to several, or negatively indifferent.” The first is true, the second false. The truth of the first is clear from what was said above: nature outside the soul—for example, Socrates’s nature—taken in itself, that is, taken alone, is not determined or appropriated to anyone, and consequently is negatively indifferent or common. The falsity of the second is clear because every proposition is simply false in which the predicate conflicts with the subject by reason of a condition explicitly implied in it. Thus “fire not brought near combustible matter burns” is simply false, because burning conflicts with fire not brought near a passive object. But the second proposition—“nature existing outside the soul is negatively common to several”—is of this kind; therefore it is false.

For clarity about the minor, know that when I say “nature in itself,” or “nature absolutely,” I say two things: nature and solitude as its condition. Likewise, when I say “nature existing outside the soul,” I say two things: nature and the particular existence joined to it as its condition. Thus something belongs or is repugnant to nature absolutely by reason of nature, and something by reason of solitude. Similarly, something belongs or is repugnant to nature existing outside the soul by reason of nature, and something by reason of its association with a particular. Since negative community, the predicate in our proposition, does not belong to nature absolutely by reason of itself—that is, by reason of nature, since it is not its quidditative predicate—but belongs to it by reason of the explicit condition expressed by “in itself” or “absolutely,” which is solitude, for nature is negatively common precisely because it is taken alone without determination to this or that, it must be repugnant to nature taken under the opposite condition, by reason of that opposite condition. Nature existing outside the soul expresses the condition opposed to solitude, since it expresses its conjunction with particular existence, which removes its solitude. Therefore negative community is repugnant to nature existing outside the soul, not by reason of nature but by reason of the condition expressed by “existing outside the soul”; consequently the proposition whose subject is nature existing outside the soul and whose predicate is negative community is simply false. As soon as nature loses solitude, it also loses community. It loses solitude as soon as it is in another.

Hence the answer to the argument appears. Although both nature and formal unity, as far as they are of themselves—that is, taken alone—are negatively common, yet, existing outside the soul, they are not common. Taken in itself, nature is not with another; yet existing outside the soul it is necessarily with another. Thus one may not infer: “Taken in itself it is not with another; therefore, existing outside the soul, it is not with another.” Likewise one may not infer: “Taken in itself it is negatively common; therefore, existing outside the soul, it is negatively common.” In both cases the same fallacy occurs, namely the fallacy of accident.

If you attend to this, you will see how Scotus’s position in Sentences II, distinction III, question I differs from ours, and how he fell into that opinion. He says that specific nature, for example humanity, by reason of itself follows these two things: formal unity and negative community, or indifference to several numerically. At the end of that question he says that one need not seek the cause why nature is common, since nature itself is a sufficient cause of its community; but one must seek the cause why it is singular, since it is not singular of itself. Thus, just as one nature is found outside the soul formally, so a nature common to several is found there.

We do not disagree with him in the first matter, but in the second. We say that nature by reason of itself follows formal unity, but we maintain that negative community does not follow it by reason of itself, but by reason of its solitude, just as we said that singularity follows it by reason of its association with existence. Since the condition of solitude does not belong to nature by reason of itself, nor by reason of the being it has outside the soul, but by reason of the intellect, which is naturally disposed to unite what has been divided, no community is found in nature before every act of the intellect. And just as one must seek the cause from which nature has solitary being and being outside the soul, since of itself it has neither, so one must seek the cause from which it has community and singularity, since of itself it has neither.

The cause from which the falsity in this Scotist opinion proceeded seems to be twofold. First, there is equivocation in the term “of itself” or “from itself.” Each can be understood in two ways. Positively, it signifies some relation of cause; negatively, it signifies solitude, that is, not being with another. Scotus understood nature to be common of itself in the first way, so that it is itself a sufficient cause of its community, as his words there show, although he should have understood it in the second way. For nature “of itself,” that is, not with another, is indifferent and common; just as when one says “nature of itself is alone,” “of itself” signifies no causality, but only the negation of conjunction with another.

The second cause is the distance between a negative proposition and an affirmative proposition with an infinite predicate, when reduplication is added. Without reduplication, an affirmative proposition with an infinite predicate entails a negative one, and conversely, as is said in On Interpretation II. With reduplication, however, an affirmative proposition with an infinite predicate entails a negative proposition with a finite predicate, but not conversely. For “man, insofar as he is man, is not white” does not entail “man, insofar as he is man, is non-white.” If man, insofar as he is man, were non-white, whiteness could never be joined to man, because what belongs to something according to itself belongs to it always, necessarily, and per se. Scotus’s reasoning plainly failed here. Since “negatively common” signifies the same as “not proper,” he argued: “Nature, for example humanity, insofar as it is such, is not proper to anyone; therefore humanity, insofar as it is humanity, is non-proper.” The defect just described is explicit.

That this was his procedure is clear from his argument. His conclusion is affirmative with an infinite predicate, for he concludes, “therefore nature of itself is common,” that is, non-proper. But the antecedent is negative: “nature is not of itself this,” that is, proper to anyone. It is likewise clear from another argument he introduces there: “It is not repugnant to Socrates’s humanity, by reason of itself, to be in another; therefore Socrates’s humanity of itself is common.” Here too the defect is evident. In the first argument “of itself” expresses reduplication, and in the second “by reason of itself,” and so forth. This is highly important in this matter and in the matter of universals, since everything depends on it. Therefore one must attend carefully: if the proposition “Nature of itself is common” is to be true, both “of itself” and “common” must be taken negatively, according to our account. Then it means: “Nature taken not with another is not proper to anyone,” which is evidently true. According to Scotus, however, “of itself” is taken positively, and wrongly; the sense is: “Nature, by reason of itself, or insofar as it is such, is not proper to anyone,” which is plainly false.

Be still more attentive: it is one thing to say, “Nature, for example humanity, insofar as it is such, is not proper to anyone,” and another to say, “Humanity, insofar as it is such, is non-proper, or common,” which has the same sense here. The first is true, because humanity, insofar as it is humanity, is not appropriately attributed to anyone.

The second point, however, is shown to be false from the same root: for it does not belong to humanity, precisely as humanity, to be appropriated to no individual. For it abstracts from both, namely from being proper and from being non-proper. For if humanity, precisely as humanity, were not appropriated, humanity would never be appropriated to anyone, because, as was said from the First Posterior Analytics, what belongs to something according to itself presupposes that it belongs to every such thing, necessarily and per se. But although it was indirectly proved above that this community does not belong to nature by reason of itself, when the falsity of this proposition was established by two arguments—“a unity existing outside the mind is common to several supposits distinct in supposit”—the falsity of that follows from the falsity of this: for what does not belong to a thing outside the mind does not belong to it by reason of itself.

I now prove it directly as follows: whatever follows a nature by reason of itself is predicated simply, that is, without any addition, of the supposit of that nature; but according to you community follows human nature by reason of itself; therefore community is predicated simply, that is, without any addition, of the supposit of human nature. The reasoning in the third figure is sound, but the conclusion is false; therefore one of the premises is false. Not the major, as will be shown; therefore the minor, which is your position. The falsity of the conclusion is clear, because “Socrates is common to several” is simply false; and even if “of itself” is added, it remains false to say, “Socrates of himself is common to several.” The truth of the major is explained thus: what follows a nature by reason of itself is either a passion, a mode, or a per se, per accidens, separable, or inseparable predicable. Now all these, if they accompany a nature by reason of itself, are so related that, just as the nature is predicated essentially of the individual—man of Socrates, for example—so these are predicated denominatively, each in its own order, of that same individual, as is clear by considering each case.

This is confirmed because, in our case, according to you formal unity and community follow human nature by reason of itself. Hence no other cause need be sought for either than nature itself; therefore, just as formal unity is predicated simply of Socrates—for “Socrates is formally one” is simply true—so community will be predicated simply of Socrates, by saying, “Socrates is common.” This is false; therefore, and so forth. What greater reason is there for unity than for community, and why should some things that follow a nature by reason of itself be predicated of individuals and others not? It will not be easy to invent the reasons Scotus gives there, since they do not conclude that community exists outside the mind, but unity; for that reason I judged it superfluous to adduce them. If any arguments from them, or from what he explains in Metaphysics VII to prove community, were brought forward, it would not be difficult to take the answer from what was said concerning the two introduced here.

For clarity concerning the second doubt, it must be known that “one,” since it signifies an undivided being, implies something positive and something privative. If we speak of formal unity and substantial numerical unity with respect to the positive element they imply, then they are really the same and differ only in reason. Thus Socrates and man are really the same and differ in reason, since the same thing is formally and numerically one. But if we speak of these unities with respect to the privations of division which they imply, then I say that they are really distinct, provided no objection is made that a real distinction must be a passion of a real being; for one is the privation of formal division and the other the privation of numerical division, just as formal division is one thing and numerical division another. Nor is it impossible for one thing to contain several substantial unities really distinct with respect to the privations implied; but it would be impossible for one thing to contain several substantial unities really distinct with respect to the positive realities they imply. Therefore the conclusion of both arguments brought forward must be granted, with different senses attached to the terms; no other answer is necessary.