Commentaria in Summam contra Gentiles, Liber II

Since it has been shown that separate substances exist in great multitude, because distinction belongs to the very notion of multitude, it remains to show how such substances are distinguished from one another ¹. On this point Saint Thomas does two things: first, he shows that they are all specifically distinguished from one another; second, he shows whence genus and species are taken in them, in chapter XCV.

On the first point he does two things: first, he proves the intended conclusion; second, he draws one corollary from it, in the chapter that follows.

I. As to the first, it is proved that there are not several separate substances of one species.

And first, thus. Separate substances are subsistent quiddities. Therefore they cannot be many unless there be many species. — The consequence is proved. For subsistent quiddities are species. Which is evident: because a species is that which the definition signifies, and the definition is the sign of the quiddity of a thing.

It must be noted here that by the name of a subsistent quiddity Saint Thomas understands a quiddity not received in any individual matter, but existing per se without any receptive subject. Such a quiddity, thus abstracted, cannot be other than one, however material it may be, as is said in De Spiritualibus, a. 8: just as, if whiteness were separated from every subject, it would be only one; and similarly humanity, if it existed apart from all supposits. Hence Plato too, positing separate universals, posited that one separate species has no diversity of individuals, but is only one. The reason for this is that a form cannot be distinguished numerically except through its receptive subject. Therefore, once the receptive subject is removed, its numerical distinction is removed, and so only one remains. And this is the foundation of this kind of argument.

II. Second, ². Separate substances have no matter at all, neither as a part of them, nor as that to which they are united as forms. Therefore, etc. — The consequence is proved. Because whatever things are the same in species but different in number have matter: for difference that proceeds from form induces diversity of species, whereas difference that arises from matter induces diversity according to number.

Note that this argument is taken from Aristotle, Metaphysics XII, text 49 ³: for by means of it Aristotle proves, according to the interpretation of St. Thomas, that the first immovable principle is one alone. Now by the name of matter Aristotle and St. Thomas do not understand every receptive subject indifferently, as some wrongly interpret it ⁴, as is clear to anyone who attentively considers the text of Aristotle and of St. Thomas; rather, matter properly so called is understood, which is pure potency in the genus of substance. For the discussion here is not about the material difference of accidents, but of substances, concerning which Aristotle also speaks in the passage cited. For in these it is true that if they are substances subsisting per se and complete in species, and there are several individuals of the same species, those individuals must have matter as a part of themselves, and thus be composed of matter and form. But if they are substances not complete in species, but which are parts of a species, they must have matter in which they are received and individuated, as is apparent from what was said above ⁵. — Nor does it stand in the way that St. Thomas, in Prima Pars, question 50, article 4, gives the example of the multiplication of whiteness, which is admittedly multiplied not by matter properly so called, which is pure potency, but by the subject as quantified. For St. Thomas did not introduce that as an example, but as a likeness. For he wished to prove his point through something similar in other cases. For just as whitenesses are not multiplied except by the multiplication of corporeal substance, which is the proper subject of material accidents, so substances that agree in species and differ in number are not distinguished except by individual matter, which is the proper subject of substantial forms and natures.

It must also be noted, when it is said that the diversity which proceeds from form induces diversity of species, that this is understood of the difference arising from form according to its proper ratio as form. For that difference which proceeds from forms distinct by their proper ratio, or from forms of different rationes, is specific; but not if it proceeds from forms distinct only materially, agreeing in one common ratio, as two intellective souls are distinct.

III. Against this argument, however, following Scotus, Secundo, d. III, q. VII ⁶, two things could be said. First, that Aristotle posited this for the reason that in Metaphysics VII, text 41 ⁷ he held that everything lacking composing matter is the same as its quod quid est primo, and in Metaphysics XII ⁸, that such a nature is of itself a this, because he posited every such nature to be formally necessary. For since whatever can be in a formally necessary nature is in it, according to him; and if several individuals could be in it, infinitely many could: it would follow that there are infinitely many such substances in act. But the foundation of his position is false, and so is what follows from it. And thus Aristotle is denied on this point by Scotus.

It could be said secondly, in response to that proposition, "The difference that proceeds from the form induces a diversity of species," that this is indeed true if it is understood that such a difference is in the form as in the first ground of differing. But then it is false that the difference of separate substances proceeds from the form. — If, however, it is understood that any difference of forms whatsoever induces a difference of species, that proposition is false.

2. The first of the things Scotus says is not in accord with Aristotle's mind. For Aristotle did not place, in Metaphysics VII, that in things without matter each thing's esse is identical with its quiddity because he held every such thing to be formally necessary, but on account of their separation from matter. Hence also in Metaphysics XII he assigns as the reason why the first immovable principle is not multiplied according to number that it has no matter, as appears there from Averroes' interpretation. Therefore, if Scotus wished to deny Aristotle on this point, seeing that his own opinion could not stand together with Aristotle's mind, he ought not to have alleged as the cause of his denial the falsity of a principle which Aristotle himself did not posit as a principle leading to that conclusion. — Moreover, even if it were granted that Aristotle assumed that as a principle of the conclusion, still the reply does not destroy his argument. For it was shown in what precedes ⁹ that what Scotus denies is true, namely that every substance separate from matter is formally necessary, and that it cannot fail from within itself.

3. Nor does the second point destroy the true understanding of Saint Thomas's proposition. For it is understood in the first sense, in which Scotus himself grants it. — But when it is added that it is false that the difference of separate substances proceeds from form in that sense, it is said that this is not false; rather, it is most true. For the first reason of distinction in them cannot be matter or quantity, since they are abstracted from quantity and from matter. Nor any absolute property: because such properties presuppose their subject as individuated and distinct—indeed, they are individuated and distinguished through their subject. Nor through haecceities alone, as Scotus himself holds: because among those haecceities there is no opposition or ground of incompossibility, yet nothing is the ground of distinction of things except by reason of some opposition; and also because individuals of the same species agree in having a haecceity, but that in which two supposits agree cannot be the ground of distinction between them. There remains, therefore, that the ground of distinction in them is form.

Third ¹⁰. The nature of separate substances, since it is incorruptible, can be preserved in a single individual. Therefore there need not be many individuals of one species among them. — The consequence is proved as follows. The reason there are many individuals in one species among corruptible things is that the nature, which cannot be preserved perpetually in one individual, may be preserved in several. This is shown by the sign that in incorruptible bodies there is only one individual of its species.

2. To this argument, which is taken from On the Soul II, texts 34 and 35, Scotus replies, where cited above at the end of ¹¹, that although in corruptible things this is one cause of the multiplication of individuals within one species, it is not nevertheless the precise cause; rather this is the cause: namely, that every nature which is not of itself pure act can, according to that reality by which it is a nature, be potential with respect to that reality by which it is this nature. And just as of itself it does not include any entity as it were singular, so no number whatsoever of such entities is repugnant to it. And thus it can be found in any number whatsoever of such. ¹²

But Scotus's response does not reach the mind of St. Thomas. For by this argument it is not concluded that it is not possible for there to be several individuals in such a species, as Scotus supposes, but that there need not be several, as is clear from the text. For this argument proceeds from what appears to us. Since we see that only the species of corruptible bodies have several individuals, but not the species of incorruptible ones, this is a sign that multiplication occurs in them on account of their corruptibility alone in respect of individuals. And therefore, since the individual of an immaterial species is incorruptible, no such multiplication of individuals is needed in them. But the argument which Scotus adduces cannot be the cause of the actual multiplication of individuals in corruptible things. Because, since that cause, according to him, is common to all quiddities, both material and immaterial, then by the same reason by which individuals are multiplied in one species of corruptible things, individuals would be many in incorruptible things: for once the cause is posited, the effect must necessarily be posited. Since this is not true, as is clear from the sun and the moon, it is clear that that is not the precise cause of multiplication in corruptible things, but rather that which St. Thomas touches upon according to the mind of Aristotle.

V. Fourth. The perfection of the universe consists chiefly in separate substances. Therefore it belongs more fittingly to them that they be many in species than many in number within the same species. — The consequence is proved. Because the multiplication of species adds more nobility and perfection to the universe than the multiplication of individuals within one species: since what is of the species in each thing is worthier than that which is the principle of individuation.

It must be noted that this argument would not conclude concerning material things, although it does conclude concerning immaterial things. For corruptible material things cannot be perpetuated in one individual, as immaterial things can. And therefore, although the universe would be more perfect at that time if all material things were distinct in species—that is, so that there would be as many specifically distinct things as there are things numerically distinct—it would not nevertheless be simply more perfect: for certain species would continually fail, and in the end there would be no species of corruptible things in it at all. But in immaterial things each species remains forever, since they are incorruptible. Therefore, if the multitude of these is not merely numerical but specific, the universe is simply more perfect, inasmuch as its principal part is multiplied into many species and many grades; and this multiplication is nobler than a numerical multiplication within the same species.

VI. Fifth. In the heavenly bodies, on account of their perfection, only one individual of one species is found. First, because each of them is composed of all the matter of its species. Second, because in one individual there is perfectly present the power of the species for that to which its species is ordered. Therefore this is much more so in intellectual substances, which are more perfect. — This argument is taken from I On the Heavens, text 92.

2. But to this Scotus replies, in the place cited above ¹³, that Aristotle certainly thought thus concerning the heavenly bodies, because he held that such a singular body was made from the whole matter of its species, both potential and actual. Yet the theologians do not agree with him, neither in the principle nor in the conclusion.

3. To this it must first be said that this argument does not succeed in proving that there cannot be several intellectual substances of the same species, as though it implied a contradiction; for this is not the mind of St. Thomas, as can be gathered from the Treatise against the Averroists ¹⁴, where, in solving the argument by which it was claimed that God could not multiply intellects, as though that implied a contradiction, he says that although an intellect would not have a natural cause of multiplication, it could nevertheless receive multiplication from a supernatural cause, nor would there be any implication of contradiction. For I hold that, according to his mind, it must be maintained that by divine power there can absolutely be several angels of the same species, even with this order of the universe standing. And perhaps in fact there are several in one species, though the cause of their distinction is not manifest to us. But when it is sometimes said, as here in certain arguments and in the First Part, q. 50, a. 4, that this is impossible, we may interpret it as meaning that it is impossible not simply, but with respect to the modes of multiplication known to us, and with respect to the mode of numerical multiplication handed down to us by Aristotle in Books VII and XII of the Metaphysics.

It is said second, that this argument proceeds to prove that in fact there are not several individuals of one species among abstract substances, by comparison with the heavenly bodies. For just as in those bodies, on account of their perfection, only one individual is found in a single species, as is evident in the sun and the moon, whatever may be said of the possible; so too, since separate substances are more perfect than heavenly bodies, it is probable that there is only one of each species.

4. A second reply is possible, holding that this argument also proceeds from impossibility, but that it does not conclude that this is simply impossible; rather, that it is impossible according to the opinion of Aristotle, who held that celestial bodies, on account of their perfection, cannot be multiplied in number within the same species. For if, according to his opinion, this is found in celestial bodies on account of their perfection, it will be found much more in separate substances, which are more perfect. And thus there is no reply to this argument to be drawn from the words of Scotus.

VII. Scotus himself, however, in the place cited above ¹⁵, held the opposite of this conclusion, speaking in terms of possibility, and he confirms his opinion with many arguments. But since Capreolus refutes them most fully in Book II of the Sentences, distinction III, question 1 ¹⁶, we shall touch upon them, and upon their solutions, only briefly.

He argues, therefore, first, because * every quiddity, insofar as it is of itself, is communicable: since neither from its perfection is it repugnant to it, nor from its imperfection*.

Second, because * any quiddity can be understood under the aspect of the universal without contradiction. This would not be so if it were of itself this *.

Third, because * God could annihilate this angel and again produce that species anew in another individual, but not in the same one: according to those who say that man could not rise again as numerically the same unless the same numerically one intellective soul remained*.

Fourth, because * the intellective souls, which are pure forms, are distinguished in number within the same species*.

Fifth, because according to Augustine in the Enchiridion, chapter XVII ¹⁷, it is unfitting that some species of intellectual nature should be wholly damned.

Sixth, because * one angel would be formally infinite: for it would be infinitely communicable, if it could be communicated*.

Finally, in the Quodlibets, question II ¹⁸, he argues, because that opinion has been condemned by several Parisian articles ¹⁹. In which it is said that it is an error to hold that God cannot make several intelligences of one species, because they do not have matter. — Likewise, that God cannot multiply individuals within one species without matter. — Likewise, that forms do not admit division except according to matter.

VIII. For the solution of these arguments, those things must be recalled to memory which were said in the preceding sections ²⁰ concerning the difference between nature and supposit. For it was shown that, since in immaterial things the nature is of itself, and not through something added, this nature and individual, in them nature and supposit do not differ intrinsically, as though there were certain principles individuating the nature which belong to the notion of supposit, but not to the notion of nature; rather, they are distinguished only extrinsically, insofar as being and other accidents are conjoined to that nature, which are not of the notion either of nature or of supposit, yet nature and quiddity exclude them, whereas supposit does not exclude them. For Gabrielity signifies only those things by which Gabriel is Gabriel; but this Gabriel signifies one having gabrielity; and it is not incompatible with him to have something other than gabrielity. From this it follows that an immaterial nature, considered in itself, is not communicable or universal to many supposits, because considered in itself it is this; just as Socrates is not common to many in the manner of a universal. Hence, just as a form which is in a subject is individuated by the fact that it is in this subject, so an intellectual substance is individuated by the fact that it is not naturally apt to exist in something, as is said in De spiritualibus creaturis, a. 8, ad 4. And thus in them there is not, on the side of the thing, a distinction between universal and singular, but nature and this nature are altogether the same.

But although this is so in reality, since nevertheless our intellect cannot apprehend immaterial quiddities as they are in themselves, it therefore apprehends them by the mode of material things, apprehending them by the mode of abstract and concrete, and by the mode of universal and particular. For it apprehends that nature itself as a certain essence absolutely, with respect to its essential principles, in the way in which it apprehends material natures through abstraction from individuating principles. And because a material nature thus abstracted is universal, therefore to an immaterial nature abstracted in this way there does not repugn, from the mode of consideration, attributing to it the intention of universality. It also apprehends the nature together with this esse and with those accidents accruing to the nature: which indeed do not individuate the nature, since it is in itself this, but rather are themselves individuated from it; yet because a nature in material things is individuated by certain particular accidents and matter, and becomes this, whence it happens that universal nature and particular nature are distinguished as things one of which adds something according to its own ratio to the other; therefore, while our intellect apprehends an immaterial nature conjoined with particular accidents, it apprehends it by the mode of the particular, and thus distinguishes in that nature the universal and the particular, as if those accidents individuated the nature. In this, however, falsity does not occur in the intellect: because this mode of understanding holds only on the part of the intellect, not on the part of the thing. For it is not necessary that the mode of understanding be the same on the part of the intellect as the mode of being on the part of the thing: since the intellect apprehends material things immaterially, and understands composites divisively.

IX. These suppositions being granted, to the first argument on the opposite side ²¹, the assumption concerning that communication by which the universal is communicated to particulars—the communication here under discussion—is denied. And it is said that it follows from the perfection of an immaterial nature that it is not communicable in this way, as is clear from the Summa contra Gentiles, chapter 8: namely, because an immaterial nature is of a higher order than all corporeal things.

To the second it is said that the assumption is true on the side of our mode of understanding, but not on the side of the thing itself, if it were understood as it is in itself. Therefore, according to our mode of understanding, it does not conflict with such a nature that it be in many individuals; yet it does conflict with it on the side of the thing. Hence it is not true that it conflicts with a nature which is in itself this one that it be understood in the manner of a universal, as far as our mode of understanding is concerned—although it conflicts with its being really in many.

To the third it is said that, if God were to annihilate an angel and produce the same species anew, He would also re-create the same angel in number. For we do not deny that what is one in number can be restored by divine power. — But as to what is said, that a man could not rise again unless the same soul remained in number, this is true, not because God could not restore an annihilated soul as the same in number, but because, if it were annihilated and afterwards produced anew, it would not properly be a resurrection of the man, but a new re-creation.

To the fourth it is said that the case is not the same for the soul as for the separate substances. For the soul is by nature the form of a body. Therefore, in accordance with its proportion to different bodies, souls are multiplied, as was shown at length in what precedes ²². But a separate substance is not the form of a body.

To the fifth, it is said that it is not unfitting, according to Saint Thomas and Augustine, that an entire intellectual species be damned; indeed, many such species are damned. But it would indeed be unfitting for the whole angelic nature to be damned. Now Augustine speaks, as is had in De Spirituali, article 8, ad 1, of the angelic nature by comparison with human nature, as of one nature, on account of the one and same order of all of them to beatitude. For the whole angelic nature was born to arrive at beatitude or to fall short of it in one way, namely immediately after the first completed election; but human nature through the passage of time.

To the sixth, it is said first that it is not unfitting for one angelic nature to be infinite in a certain respect, namely within its own species. — It is said second that one angelic species does not contain the perfection of infinitely many individuals, if it is posited as not multiplied: for it is not only not suited to exist in infinitely many individuals, but not even in two.

X. Finally, it is said first that Bishop Stephen of Paris revoked those articles in the year of the Lord 1325, insofar as they touch the doctrine of Saint Thomas.

It is said, second, that the doctrine of Saint Thomas was approved by Pope Urban V and John XXII. Indeed, it was even marvelously commended by Urban in the decretal beginning "Laudabilis Deus in Sanctis suis" ²³ as true and catholic. He even commanded that the University of Toulouse strive to amplify it with all its strength. Therefore we need not concern ourselves with those articles.

It is said thirdly that those articles are directly opposed to the doctrine of the Commentator, who holds that human intellects cannot be multiplied according to number, on account of their immateriality ²⁴. Hence the sense of the first article is that it is an error to say that, because the intelligences do not have matter, namely as a part of their substance, God could not make several of the same species. Similarly, the second and third are to be understood of matter which is a part of a thing capable of being multiplied. Or indeed all are to be understood of matter from which form depends in its esse. — But in none of these ways do we assign immateriality as the cause of the non-multiplication of separate substances, namely, that they are not composed of matter and form, or do not depend upon matter in their esse; rather, that they are altogether separate from matter, because clearly they are neither composed of matter and form, nor dependent upon matter in their esse, nor are they forms in any way giving esse to matter.

It is said, lastly, that these articles are set down against those who hold that it is repugnant to the absolute omnipotence of God to produce several individuals in an immaterial nature. But we do not say this, as was shown ²⁵. Hence the said articles are not against the mind of St. Thomas.