Cursus Philosophicus Thomisticus, Secunda Pars Artis Logicae

I presuppose that Porphyry DEFINES species in both ways. As subjectible, it is said to be “that which is placed under a genus and of which the genus is predicated in answer to what it is.” As predicable, it is defined as “that which is predicated of many things differing in number, in answer to what it is”; here its one relation is explained—not to what is above it, but to its inferiors, in relation to which it is superior. Note in passing that there is no vicious circle in Porphyry’s definitions, when he defines genus by reference to species, of which it is predicated, and species by reference to genus, under which it is subjectible. First, because between mutual correlatives such as genus and species there must necessarily be this mutual relation, without a vicious circle, precisely because they are mutual; and consequently each must be included in the definition of the other, as we shall say below, q. 17, art. 6. Second, species is not defined only by that definition, namely by its relation of subjectibility to genus, but also by another, namely its predicability to inferiors, and so it is not made known precisely through genus, but in another way. Whenever something is presupposed to be made known and defined by another definition and in another way than through that with which it is defined circularly, no formal circle is committed, but only a material one, which is not vicious: the same is not made known by the same alone; rather, what has been made known from elsewhere manifests its own knower and definer in another way, as we shall explain further in the Posterior Analytics, q. 25.

Since this second predicable involves both of these intentions, predicability and subjectibility, THE DIFFICULTY HAS TWO PARTS: First, which of these intentions formally constitutes the second predicable. Second, how one stands in relation to the other—whether they are wholly disparate, or whether one is a proper attribute and something consequent on or modifying the other.

It is certain that these relations or intentions are distinct relations, since they have distinct terms and foundations. The term of subjectibility is the very superior under which it is subjectible; its foundation, however, is inferiority or dependence on that superior. But the terms of predicability or universality are the very inferiors of which it is predicated, while the foundation is taken from the community of nature itself, in which those inferiors agree and which is communicable and superior to them. Therefore, the foundations and terms of these relations are distinct; a relation takes its unity or diversity from its foundation and term. Although the very character or intention of species is constituted not by several relations but by one, it can nevertheless have several properties or required conditions, just as predicability is also a property of universality. We are asking which relation is essential to and constitutive of species.

As for this difficulty, some judge that predicable species does not belong to species as species, but that it is constituted as a species by its subjectibility to genus, from which its predicability and universality follow. This is because the proper character of species is to be correlative to genus; it has this character of a correlative not by reference to the inferiors of which it is said, but by reference to the genus under which it is placed. This is taken from Cajetan in the chapter “On Species.” Others, at the opposite extreme, think that species is constituted by universality in such a way that subjectibility to genus also belongs to it insofar as it is universal and by reason of its universality. This is attributed to Toledo, On Species, single question. Others say that subjectibility and predicability are disparate relations and that neither arises from the other as an attribute from an essence. See the Carmelite Course, here, disp. 6, q. 3; Magister Cabero, disp. 3, dub. 2; and Merinero, disp. 3, dub. 2.

Authors also differ on the second point. Some, such as Cajetan in the chapter “On Species,” think that subjectibility to genus is the first character of species and that predicability to individuals arises from it. This is said of atomic species, in which one of these intentions sprouts from the other. For from the fact that a species is placed immediately and directly under a genus, it follows that the species is predicable. In a subaltern species, however, the character of species found in it is properly subjectible species; for its predicability is not only of many things differing in number, but also of things differing in species. Others, by contrast, think that the intention of predicability and universality is so primary in species that subjectibility arises from it.

NEVERTHELESS, I SAY FIRST: The intrinsic and essential constitutive principle of species, insofar as it is the second predicable divided off from the other predicables, is a universality of such a kind that it signifies a relation and predicability to many things differing only in number.

THE REASON IS that species is one of the five predicables insofar as it shares in the character of a universal, since these five predicables are certain species of universal, as was proved above.¹ Therefore, its constitutive principle must fall within the breadth and character of universal; hence it is constituted not by subjectibility but by superiority.

The consequence is evident, because it is inconsistent for a relation in general to signify a tendency toward one term, while a relation that is its species and contained under it tends toward the opposite term. For example, if the relation of a father in general regards a son, a particular relation of father cannot regard a grandfather, but must also regard a particular son. It is clear, however, that the relation of universality in general, which is the genus of the five predicables, regards inferiors as its proper term. Therefore, such a universal relation as species cannot, formally speaking, regard and be constituted by a relation to superiors, but to inferiors. Therefore, it cannot be formally constituted as the second predicable by subjectibility, but by such universality or predicability as regards these inferiors. Cajetan considered this argument so difficult in the chapter “On Species” that he left it unanswered.

I SAY SECOND: In the second predicable, predicability and subjectibility cannot concur accidentally and be disparate; rather, either in themselves or through their foundations, one determines and modifies the other.

THE REASON IS that the second predicable is not universal in just any way, but is a subordinated universal and less than another, namely, genus. Therefore, what conduces to its being a universal less broad than another cannot be disparate from the constitution of such a universal, since it belongs to its intrinsic character to be a subordinated and lower universal. It is like the fact that subordination to a first cause is not disparate from what constitutes a secondary cause; and in political order, it is not accidental or unrelated to the constitution of an inferior minister that he is subordinated to a superior, and the superior minister to the king, since this is part of the character of such a minister by reason of the subordination of an agent. Thus species is essentially predicated of inferiors, but it is not accidental or disparate to it; rather, it is required of itself that it be subordinated to a superior universal under which it is contained, insofar as it is a less universal.

Nor is it enough to say that being subject to a genus belongs to the specific nature itself, while another intention, subjectibility, is joined to it accidentally. For subjectibility and predicability are not the same relation and intention. This, I say, is not enough. For although predicability and subjectibility are two relations, precisely because the predicability that belongs to the character of species is not supreme but inferior predicability, it requires of itself, and not as something disparate, that on the part of its foundation it ground a relation of subjectibility, without which the character of inferiority cannot be understood; for every inferior is subjectible. Therefore, on the part of their foundation, predicability and subjectibility are united of themselves and are also connected to one another; they do not concur accidentally in the character of species. Likewise, universality and predicability are two distinct intentions or relations: one regards inferiors as superior in being, the other in predicating, that is, in verifying that one thing is another through the application of one to the other. Nevertheless, one follows upon the other and is connected to it of itself. It is true that, because their being consists in being known, one can be known without the other and can actually exist without the other in the very act of knowing. For this connection of intentions is not with respect to actual existence, as though one followed upon the other in being, since being belongs to them not through a consequent relation but through cognition. Rather, it is a connection by reason of their foundation, because the foundation founds one in such a way that, by virtue of that very thing, it also calls for the founding of the other.

I SAY FINALLY: Subjectibility does not flow from universality taken precisely, much less does predicability arise from subjectibility. Rather, the prior and more essential intention in the second predicable is a restricted and contracted universality; from this universality, insofar as it is thus restricted and modified, immediate subjectibility to genus arises.

THE REASON for this conclusion is taken from what has been said: the second predicable is essentially and of itself a certain universal, since universal is divided as a genus into these five predicables. Therefore, the intention of universality as thus determined must essentially belong to it: namely, a universality that regards only inferiors distinct in number. From universality in the line and relation of universality that regards only inferiors, however, only what belongs to superiority can follow, not what belongs to inferiority and subjection. Therefore, the intention of subjectibility does not follow from universality. But because universality is restricted and contracted, subjectibility can follow by reason of its being restricted, as certain attributes in a creature follow from its being a created being, or from its being a certain kind of being, for example a substance or body; others follow from its being from nothing, for example its being defeasible, capable of sin, capable of annihilation, and so on. Likewise, in a cause, subjection to another cause does not follow from its being causal, or from the line of causality; rather, it follows from the fact that the cause is limited, dependent, and inferior in causing. In the same way, subjectibility does not follow as a proper attribute from universality as such, or from its relation and line—even from specific universality—but follows from a universality that is dependent, limited, and subordinated to another, or less than another: a universal above it, which is genus.

From this conclusion it is understood how these two intentions, subjectibility and predicability, are connected in the second predicable within one form of universality. Since they do not concur accidentally in this second predicable, they must follow of themselves from some form and belong of themselves by reason of that form. Thus subjectibility follows from limited and subordinated universality on the side of subordination and limitation, while predicability follows on the side of universality; just as an inclination to virtue follows from a human being insofar as he is rational, while the capacity for sin follows insofar as he is defeasible and from nothing. It is likewise clear how species is intrinsically and essentially correlative to genus insofar as it is subject to it and inferior to it; but this belongs to species insofar as it is a limited and subordinated universal.

From this it is evident that the division of species into predicable and subjectible is not a division into different things, but into different attributes or modes of the same thing, by which it has different relations, namely to superiors and inferiors.

THE ARGUMENTS ARE ANSWERED.

The first argument is as follows: Most formally, insofar as it is species, species has being only as correlative to genus. But insofar as it is a correlative, it is not predicable but subjectible. Therefore, formally, insofar as it is species, it is not predicable.

The major is certain, because genus is defined of itself relatively to species as its proper correlative; therefore, formally, species as species is correlative to genus. The minor is clear, because as a correlative it regards that of which it is correlative; but it is formally correlative to genus; therefore, formally, as species it regards genus. But insofar as it regards genus, it is not predicable but subjectible; therefore, it is essentially constituted by subjectibility rather than by predicability.

The argument is confirmed: a subaltern genus is more universal than the lowest species, since it is predicated of it; but it is not constituted in the character of a subaltern genus by predicability. Therefore, much less is the lowest species constituted in that way.

The minor is proved: a subaltern genus is not constituted as such either by predicability of many things differing in species or by predicability of many things differing in number; therefore, it is constituted by no predicability. It is not constituted by predicability of many things differing in species, because this also belongs to the highest genus and so is not the proper character of a subaltern genus. Nor is it constituted by predicability of many things differing in number, because this also belongs to the lowest species. Therefore, it is constituted by no predicability, but by subjectibility.

I ANSWER: There are various opinions about the proper and per se correlative of genus; you can see them in the Coimbra commentary, q. 2, “On Species,” art. 1. Some think that genus as genus alone and adequately refers to species, and does not refer to individuals in the manner of a genus. Others say that the adequate correlative of genus is something abstracted from individual and species, which they call “subjectible in complete quid,” because both individual and species agree under this character. Still others, and better, think that the immediate and formal correlative of genus is species, but not in every way and not adequately. For an individual is also subject to genus, but not formally as species is; it does not contract genus by formal division as species does, but materially, namely through material and individuating conditions in which species is sustained and through species genus is sustained. Therefore, we say that species is indeed correlative to genus, but formally so—that is, it formally contracts genus through a difference that makes it differ formally and specifically, not numerically. From this it is correlative and subjectible to genus, but it is also properly and of itself relative to individuals, because it is not the immediate formal correlative of genus unless it is also universal in itself, although limited and contracted or dependent, since it is subject to genus. Thus being correlative to genus is not the whole essence of species, but rather its condition. Directly and of itself, species is universal and predicable of an individual, with the dependence of subjectibility to genus.

In answer to the confirmation, there is a disparity between the lowest species and a subaltern species, because a subaltern species is not universal in the character of species but in the character of genus. For it has universality and predicability only “in answer to what it is, incompletely,” while it has subalternation in the character of subjectible species, insofar as it is subject to a superior genus and contracts it by a difference, thereby making a species that is not the lowest but a subaltern species, which is also called a subaltern genus. In truth, however, subalternation belongs to it insofar as it is a certain species. Thus it has universality under one character, namely as genus, and subjectibility under another, namely as species. The lowest species, by contrast, does not have universality in the character of genus, but in the character of the second predicable, “in answer to what it is, completely”; and therefore universality is prior in it, so that it is constituted as the second predicable, to subjectibility in that same lowest species.

The second argument is as follows: A subjectible species can be given that is not predicable, such as an angelic species, on the opinion that it has only one individual, which we shall prove below.² Conversely, a predicable species can be given that is not subjectible, such as substance when it is predicated of this and that substance as individuals, although substance is not subject to another superior, since there is no other grade above substance. Therefore, that some species is both subjectible and predicable is accidental concurrence.

The argument is confirmed: subjectibility to genus does not conduce or proportion species to be predicated of individuals, nor does predicability of individuals conduce to its being subject to genus; for one of these relations is not derived from the other, nor does one ground the other. Therefore, they are accidental and purely concomitant.

I ANSWER by denying the antecedent, if we are speaking of species properly so called, which is the second predicable. As for angelic species, we shall show below that it is not only subjectible but also predicable, for it is universal, not as a genus, but as signifying the whole quiddity completely. As for substance, we say that even in relation to this and that individuated substance it is not species as the second predicable, since it is predicated in answer to what something is incompletely; rather, it is a generic predication, though mediated, because genus is predicated mediately of individuals, as we showed in the preceding question when explaining how genus is predicated of generic individuals; this will be explained further in the next question.

In answer to the confirmation, subjectibility to genus does not conduce to predicability of individuals considered absolutely, but it does conduce to predicability as limited and dependent, and insofar as it is the lowest predicability; for this cannot exist without such subjectibility. It is like obscurity: it does not of itself conduce to cognition, but it does conduce to cognition of a certain kind, namely faith, which is imperfect and limited cognition that calls for that modification of obscurity.

The final argument is as follows, to prove that subjectibility is found prior to predicability in species: subjectibility of species is that by which it is made immediately subjectible to genus. But immediate subjectibility is prior to universality. Therefore.

The minor is proved: it is prior for a specific nature to be a nature contracted with respect to genus than to be contractible with respect to individuals; for it is constituted in itself by contracting genus. But being constituted is prior to being contracted by others. By contracting genus, however, it is subject to genus; by being contractible to individuals, it is universal to them. Therefore subjectibility is prior to predicability.

I ANSWER by denying the minor. In answer to the proof, we say that the contraction of genus, insofar as it pertains to the very constitution of a nature, which occurs through genus and difference, is not subjectibility; for the constitution of a nature pertains to the nature in itself and to the first intention, whereas subjectibility signifies the relation by which species is coordinated with genus, and so pertains to the second intention of the nature, not to its constitution. In this order of intention, universality and predicability are prior in constituting the second predicable, which is species, to subjectibility. This is so even though, with respect to the nature in itself, the contraction of genus—which is the foundation of subjectibility—is understood before contractibility to individuals, which is the foundation of universality. But in constituting species, this is prior to that.

TWO THINGS MUST BE NOTED HERE: First, concerning the defined thing of these definitions, by which the predicable and subjectable species are defined (we set down the definitions at the beginning of the preceding article); second, concerning the parts of the definitions themselves that must be explained.

Concerning the first, the same must be said about the defined thing of these definitions as was said about the defined thing of genus in the preceding question¹; for the account is the same in one case and the other.

Concerning the second, as regards explaining the parts of the definition, a common difficulty seems to arise: these definitions apply to things other than what they define. For a subjectable species is said to be that which is placed under an assigned genus, or of which the genus is predicated in answer to “what.” But both descriptions apply no less to an individual, since an individual too is placed under a genus and the genus is predicated of it in answer to “what.” If you say that a species is placed immediately under a genus, whereas an individual is not, this is to add a new part to the definition—namely, the word “immediately”—which the definition does not contain. Besides, the case of generic individuals is an objection, such as this animal, this body, and so on, of which genera are predicated immediately. Similarly, the definition of a predicable species applies to things other than what it defines. First, because it applies to genus: a genus too is predicated of individuals in answer to “what”; and although it is predicated incompletely and in a way different from a species, this is not explained in the definition of species, so that the definition is deficient. Second, many things are predicated of many numerically distinct things without being species, such as incomplete beings—for example, motion, soul, matter, a point, and the like—and God is predicated of the three persons, yet is not a species. Third, the third predicable is also predicated in answer to “what,” that is, essentially, and of many numerically distinct things, as in the case of atomic species. Finally, the species of angels truly are species, yet they are not predicated of many numerically distinct things, because such many things are impossible, as we shall say in the next article.

THE ANSWER IS that these definitions are nevertheless rightly given. There is no need to dwell on whether they are essential or descriptive. For just as we said that the definition of genus is descriptive because it is given through the proper property of universality, which is predicability, so the definitions of species must be judged descriptive: the predicable species is defined through its property of predicability itself, which is a property of universality, while the subjectable species is defined through the property of specific universality, insofar as this universality is imperfect and dependent on the universality of genus.

To the first objection against subjectable species, then, the answer is that in all these definitions of the predicables their proper genus, which is the universal, must be understood. The definition therefore means that species is a universal placed under a genus, and difference is a universal predicated of many in answer to “what sort,” and so on for the others. This does not add any extraneous part to the definition, but supplies something necessarily presupposed. For the universal is the genus of the five predicables, and therefore must necessarily be understood in every predicable. Consequently, the part “immediately” must also be understood: species is that which is subject to a genus immediately, since here we deal only with what is subject to a genus as a universal, or as one of the five predicables. An individual, by contrast, is not subject as a universal, and therefore is not subject immediately.

The objection concerning generic individuals is answered by saying that they are not subject as a universal or, strictly speaking, immediately, but only in a qualified sense and as regards explanation. For when one says “this animal” or “this body,” one explains a generic level together with individuation; nevertheless, something not expressed in that generic individual intervenes between individuation and genus. For in reality no animal or body is found as singularized except through a species. A species, however, is subject to a genus so fully and strictly that not only is nothing said to intervene, but nothing can intervene in it between the species itself and the genus. This is what it means to be subject immediately in the strict and absolute sense.

To the second objection against the definition of predicable species, the answer is that, as we said in the preceding question, genus is not formally and immediately predicated of many numerically distinct things, but materially—that is, because they are contained under a species of which it is predicated per se, formally, and directly. Thus the predication of genus must be understood as being in answer to “what,” but incompletely. This does not add anything to the definition; it explains what is already implicit in it. For if genus is predicated of things differing in species, it cannot predicate the whole quiddity, but only a part: that which can be contracted by a difference and, together with the difference, constitutes a species. This is to be predicated in answer to “what” incompletely: not the whole and complete quiddity, but the part that is genus.

To the second point, the answer is that incomplete beings belong to species or genus only reductively, and not per se, just as they do to a category. Hence they have many numerically distinct instances only reductively and in a qualified sense. God, however, is not predicated of the three persons as something that can be multiplied and contracted in them, but as one singular nature predicated of several supposits of the same singular nature. Therefore neither does the divine nature function as a universal, nor do the persons function as inferiors contracting a higher nature and distinguishing it numerically. Rather, the supposits are multiplied without the nature being multiplied: there are three supposits of the same singular nature.

To the third point, we have already said above, in the preceding question,² that difference is indeed predicated essentially, but not in answer to “what,” because it is not predicated substantively but adjectivally or qualificatively. Thus, although it is predicated in answer to “what” with respect to essence, it is not so with respect to mode: it is not predicated essentially in a substantive manner, but essentially in an adjectival manner, or in answer to “what sort.”

The answer to the final point will be given in the following article.

To make the POINT AT ISSUE clear, two things must be noted.

First, among natures that have only one individual, a threefold distinction can be considered. For some nature in fact has no more than one individual, yet can have more in possibility, as with the moon, the sun, and the like. These have matter that is divisible absolutely, though not naturally; from the division of matter, however, multiplication of individuals is apt to follow. Another nature can have no multiplication of individuals, either in fact or in possibility, by division of matter, because it lacks all matter, as do complete spiritual substances, such as angels. It is nevertheless disputed whether they can have numerical multiplication on some basis other than division of matter; and even if they cannot have it, those natures can still be conceived as universal, with a certain indifference and potentiality toward the one individual they have. Finally, there is another nature that not only has no several individuals in fact or in possibility through multiplication of the nature, but cannot itself be conceived with any potentiality for individuation or as contractible by singularity, because it is pure act, namely God. Thus it cannot be universal in being, although the nature itself can be conceived without its individuation being made explicit; in that way it can be signified as a common term and not a singular term, just as the name “God” is a common term in signification.

There is no difficulty here concerning the first nature, since it is clear that a nature can be predicated of many when many possible individuals exist of which it may be predicated. Nor is the present question about the third nature; we dealt with it above, q. 5, art. 3. The whole difficulty concerns the second nature. We are not now disputing whether several angels distinct only numerically are possible; that is treated in 1 p., q. 50. If several numerically distinct angels are possible, the question presents no difficulty: angelic nature should be treated like the sun, the moon, and other natures in which several individuals are possible. But if we grant that several individuals in angelic nature are impossible, the present difficulty arises: does it suffice for a species to be predicable of many that, from the mode of conceiving it, the nature is conceived as indifferent to individuation—not because it in fact has, or can have, many individuals in reality, but because such individuals are not incompatible with that nature as conceived in this indifferent way?

Second, observe that having several individuals occurs in two ways: either positively, or through nonrepugnance, at least on the part of some principle. This distinction is taken from St. Thomas, Quaest. de Spirit. creat., art. 8, ad 4.¹ To be predicated of many positively is to have a positive foundation in the thing itself for predication of many, namely because such multiplication is found in reality. From this the basis is taken for conceiving one nature predicable of them. A nature is said to be predicated of many by nonrepugnance when it is not found in many things in reality, but only in one; nevertheless, the nature is related to that one individual in such a way that it can be abstracted from it in precisely the same way as it is abstracted from several, the nature remaining indifferent and potential toward that individuation. Thus, by virtue of this abstraction the nature is not incompatible with several individuals, even though in reality it is incompatible for another reason, namely its lack of matter, without whose division individuals are not multiplied.

In this difficulty, then, it is commonly held OUTSIDE THE SCHOOL OF ST. THOMAS that, assuming St. Thomas’s view that several individuals in the same angelic species are impossible, such a species will be subjectifiable but not predicable. For it seems contrary to all reason that something be predicable of many when the very act of predication of many is incompatible with it. That this act is incompatible is clear, since the existence of those many is incompatible with it. These authors do not, however, deny that angelic nature can be conceived as universal negatively and metaphysically, since it can be conceived without any singularity or individual difference—that is, as remaining abstracted from individuation.

NEVERTHELESS, the Thomists commonly defend the opposite view and hold: Simply because a basis is given in such a nature for conceiving it as abstracted from that sole individuation, and as indifferent and potential toward it, it can be conceived as universal and as a species predicable of many. For this, however, it is necessary that angelic nature not be conceived adequately and fully as it is in itself, but inadequately and after the manner of things composed of matter and form.

This view is plainly drawn from St. Thomas’s teaching in Quaest. de Spirit. creat., art. 8, ad 4,² where he says: “Just as this whiteness is not prevented from having many individuals under it because it is whiteness, but because it is in this thing—which pertains to the notion of an individual—so the nature of this angel is not prevented from being in many because it is a nature in this order of things—which pertains to the notion of a species—but because it is not apt to be received in a subject—which pertains to the notion of an individual.” So St. Thomas. These words are too clear to need any elaboration. He says the same in Opusc. 42, ch. 5³ and 1 p., q. 13, art. 9, as do Cajetan there, De Ente et Essentia, ch. 5,⁴ q. 9, ad 2, and the commentary on the chapter “On Species” in the Logic.

THE WHOLE FOUNDATION of this view is that, although in such a nature one cannot conceive a relation positively tending toward several individuals, nor the unity of a nature collected from several individuals, since in truth they do not exist, one can nevertheless conceive the indifference of the nature and its potentiality toward one individual of such a kind that, of itself, it would suffice for several, if they were posited in reality on some other basis. Thus, by its own mode the indifference of the nature is communicable to many; but, on the part of those to which the communication would be made, that communicability cannot be exercised. The reason is that one cannot deny that an individual of angelic nature exists in a category, since the angel found in reality is a categorical substance. It is not posited immediately under a genus; therefore it is posited immediately under some lowest species. But the lowest species under which the individual is contained is superior to it, and therefore universal and predicable with respect to it. For such a species is not predicated of the individual as an equal; otherwise the species would not be predicated of Gabriel’s individual by a superior-of-inferior predication, but there would be something like an identical predication, as when one individual is predicated of another. It is therefore a predication of a superior of an inferior. Otherwise the species could not be preserved in only one individual, as we shall say in the next article, if, while having only one individual, it could not be conceived as superior. From this it clearly follows that the nature and species, conceived in this way as superior to that individual, has an indifference that of itself suffices for several individuals, although multiplication cannot in fact be exercised because a required condition is lacking, namely division on the part of matter. For the species abstracted in this way from individuation does not actually include it, but includes it potentially; consequently, just as it includes neither individual unity nor plurality, so neither does the force of that concept exclude a plurality of individuals. Therefore, if the force of that concept does not exclude plurality, the nature has by the force of its indifference an ordering toward many—not positively, but by nonrepugnance.

This is confirmed, because the incompatibility with several individuals in angelic nature does not follow from all the nature’s predicates, but from the precise character of its inability to be received in matter: it is not individuated by the designation of matter, but by lacking matter. Hence the incompatibility with plurality arises not from the nature, but from the mode of individuating the nature, since the only principle of individuation is the form’s very inability to be received. From this, and from no other source, it has incommunicability, which is the basis of individuation. Therefore, if the nature is conceived inadequately—that is, with regard to its character as a species, and not to the very mode by which it is individuated—it is not taken as incompatible with multiplication of individuals and consequently as having several individuals by nonrepugnance. Although it does not positively regard many, this is not a defect in the nature itself, but because those many do not exist.

But what some say—that angelic nature is positively common to one real individual and several fictitious ones—is futile, because to regard several fictitious things is not to regard several things in which it can exist and of which it can be predicated. For it is predicated only fictitiously of several fictitious things; to be predicated fictitiously is not to be truly predicated, nor truly conceived as predicable.

YOU WILL SAY: Then there is no difference between God and angelic nature. For God too can be conceived as a common king without singularity and signified as a common term, as we said above, q. 5.⁵ Therefore, from the mode of conceiving, God will have universality and consequently the status of superior and inferior, which cannot be admitted in God.

It is answered that the cases differ. Although God can be conceived without singularity and consequently signified in a common mode, the nature itself so conceived does not remain indifferent and potential toward individuation, since it is conceived as pure act. Though, owing to the imperfection of our concept, it does not always make singularity explicit, on its own side it does not remain indifferent to singularity. It is like conceiving one attribute without another: the one does not remain potential and indifferent to the other, but merely does not express it. Hence divine nature is common in only one respect, namely because of the imperfection of our concept; it is not common by reason of indifference and potentiality on the part of the nature. A composite nature, by contrast, is universal in three respects: from the mode of conceiving, by abstraction from singulars; from the nature’s own indifference; and from the plurality of individuals toward which the universal relation can be directed. Angelic nature is universal in only two respects: from the mode of conceiving and from the nature’s own indifference, although, because several individuals are lacking, this communicability to many cannot be exercised in reality; thus it is universality without exercise. For divine nature to be signified by a common term, it suffices that it be conceived without singularity through the mode of signifying. But to be a genus or species, it must be conceived as contractible and determinable; consequently, the contracting principle must be more determinate and more actualizing. This cannot be conceived without potentiality in what is contracted and greater actuality in what contracts. All of this is incompatible with pure act.

THE ARGUMENTS ARE ANSWERED.

The first argument is made by the argument suggested in reporting the opposing view: Angelic species is incompatible with being predicated of several, and this incompatibility is intrinsic to its nature, since multiplication of such a nature in singulars is intrinsically impossible. Therefore, it is incompatible with being a species predicable of many. For predicability does not belong to something to which predication itself is incompatible, just as the power of seeing does not belong to something to which vision is incompatible.

This is confirmed: the formal unity found in a predicable species is taken by the intellect from the similarity and dissimilarity of individuals and their agreement with one another; there is no other basis for this formal unity. Therefore, when the agreement of several individuals is lacking, nothing remains from which to derive the formal unity of a species, which is the unity of several things agreeing in some degree.

THE REPLY IS: The antecedent is distinguished. Angelic nature is incompatible with being predicated of many by reason of its mode of individuation and the incommunicability of the form: granted. It is incompatible by the force of its nature and its indifference: denied. And although the mode of individuation itself is intrinsic to angelic nature, it is not so according to the concept of nature as nature, but as unable to be received and as including the mode by which the nature is individuated. Hence, although nature conceived adequately together with that mode cannot be predicated of many, if it is conceived inadequately, without that mode and with potentiality for it, it is conceived as predicable of many—not positively, because there are not many that terminate the relation of predicability, but by nonrepugnance, so far as concerns the concept of nature as nature, conceived without that mode, even though that mode belongs to it by its own nature. Many things cannot be posited in reality absolutely and simply, yet are said not to be incompatible under the concept of some principle because they are not incompatible by the force of that principle. As St. Thomas observes, Quaest. de Spirit. creat., art. ult., ad 7,⁶ substance can be understood without some accident, although in reality no substance can be created without some accidental predicate, at least without existence itself. Thus, while angelic nature remains with its mode of individuation as it exists in reality—that is, without reception and division of matter—its individuals cannot be multiplied. Yet by the force of the nature, not as it takes on the mode of individuation but under the precise concept of nature as potential for this individuation, it is related to several by nonrepugnance. And if vision itself is intrinsically incompatible with something, the power of seeing is incompatible with it; but if vision is barred by some extrinsic mode or impediment, the power of seeing is not thereby incompatible by the force of an intrinsic principle.

And when it is objected that it cannot be universal except with respect to several fictitious individuals, since in reality they are impossible:

The answer is that those several individuals are not impossible by the force of the concept of nature, although they are not absolutely possible in reality by the force of that concept. For something to be possible in reality, it must be possible when all the factors that concur in reality are taken into account. In reality, however, the mode of individuation concurs in the nature itself, and from this they are impossible. For them to be called not impossible so far as the force of the nature is concerned, it suffices that, on that side—that is, by the force of the precise concept of nature—they are not impossible. Therefore, it is said only to regard those many by nonrepugnance, and, so far as the force of the nature is concerned, not positively in reality and absolutely.

To the confirmation, the reply is that in composite natures formal unity is taken from the positive agreement of several individuals. In simple natures, however, it is not taken from the positive agreement of several, but from the very unity of the nature conceived without individuation and with indifference—a unity that of itself is not incompatible with being communicated to many when conceived without the mode of individuation and after the manner of a composite thing. It is better to take formal unity from the indivision of the specific nature than from the agreement of several individuals.

The second argument: That mode of nonreception in matter belongs essentially to an angel, since by it the angel is distinguished from a rational soul, which is a form received in matter. Therefore, the specific nature of an angel cannot be abstracted from that mode of individuation, which consists in nonreception in matter.

The consequent is clear, because however much angelic nature is abstracted, it cannot be abstracted from what is essential to it. Otherwise it would not be abstracted but destroyed, just as if a human being were conceived without animality: that would be to conceive an essence without what is essential to it.

Nor does it help that it is conceived inadequately or after the manner of a composite thing, and so can be conceived in a mode communicable to many.

The first point is challenged as follows: otherwise Peter could be conceived as universal, and likewise divine nature. For Peter, inadequately conceived, makes explicit only the nature, not the individuation. Consequently, if an inadequate concept of a thing intrinsically singular, such as an angel, suffices for it to be called universal, why could Peter too, who is intrinsically singular, not be conceived as universal if conceived inadequately—that is, with regard to the nature and not the individuation? The same holds of divine nature, which is essentially singular.

The second point is challenged as follows: even if we conceive angels after the manner of a corporeal thing, we do not attribute the properties of corporeal things to them; rather, we remove them, because such properties are incompatible with angels. Therefore, since numerical multiplication, which belongs to corporeal things, is incompatible with spiritual things, we cannot attribute it to them.

THE REPLY IS: We grant that angelic nature is essentially incapable of reception in matter and lacks matter, and that this lack of matter can never be abstracted from it. Nevertheless, we deny that it cannot be abstracted from its singularity, because the lack of matter and its nonreceptibility are not the angel’s individuation itself, but its root. For individuation in an angel signifies not only the root and principle of incommunicability, but also the formal designation and determinate specification of the individual, which in angels also depends on, or signifies an ordering toward, extrinsic predicates—for example, subsistence and accidents. It is clear that an angel’s own personality could be separated from it, as if angelic nature were assumed by God; yet personality is the terminus of singularity. Hence singularity and individuation signify an ordering toward certain extrinsic things and do not belong purely to the angel’s essential constitution. In corporeal things, matter is considered in two ways: as composing or constituting the nature itself, and as being radically the principle of individuation and numerical multiplication—remotely in itself, but proximately as designated by quantity. Yet when nature is considered in common, the character of matter is considered as constituting it, not as the principle of individuation. The opposite obtains with the lack of matter and nonreceptibility in it, as found in an angel: two aspects can be considered, one insofar as it pertains to the constitution of a simple and purely spiritual form, the other insofar as it pertains to the mode of individuation, by making such a spiritual nature incommunicable and incapable of multiplication. These aspects are distinguished from each other. The lack of matter required for the constitution of such a nature is nothing other than the character of a simple form insofar as it is an immaterial form; as such, it does not yet ground incompatibility with multiplication. But the lack of matter insofar as it supplies a mode of incommunicability and grounds subsistence and complete singularity does supply a mode of individuation and is incompatible with multiplication. Hence, when we abstract an angel’s specific nature from its mode of individuation, we do not abstract from that nature what is essential to its lack of matter as regards the constitution of its quiddity. Rather, we abstract what pertains in that nature to the mode of individuation, which originates radically in the specific nature itself but does not formally consist in it, since its designation depends on extrinsic predicates.

To the objections raised, the reply is: To the first, Peter makes explicit individuation itself not only radically but also formally; hence he cannot be conceived without individual difference, even inadequately, unless Peter’s concept is destroyed and the concept of nature taken instead. Angelic nature, however, does not formally make individuation itself explicit, although it includes its root under the formal character that constitutes an immaterial nature, not under the formal character of producing and grounding individuation. Divine nature, for its part, can indeed be conceived as a nature without singularity, but not as universal, since it cannot be conceived as contractible by differences, being pure act and in no way in potency.

To the second objection it is said that when we conceive an angel after the manner of a corporeal thing, we do not attribute the conditions of a corporeal thing to it by way of attribution and judgment. Rather, by way of a simple representation, we apprehend it after the manner of a corporeal thing, without individuation, not making explicit everything in angelic nature—not with respect to the predicates that constitute its quiddity, but insofar as it is the root of individuation. For if it were conceived fully and adequately, making explicit what is contained radically and implicitly in the nature, it could not be conceived as universal, because this would make explicit the mode of the nature that is singularity and incapacity for multiplication. St. Thomas also affirms this in 1 p., q. 13, art. 9.

You may still object: angelic nature is not only in a category as conceived after the manner of a corporeal thing; it is also in a category in itself, since it is a finite and created being. Therefore, in itself, even if it is not conceived after the manner of a corporeal thing, it has the character of a genus and species predicable of many, since without this it would not be placed in a category.

An objection is also raised: a corporeal nature, once the root of individuation—which is designated matter—is posited, cannot be conceived as universal, because universal nature abstracts from that root. Therefore, if the species of angelic nature itself is the root of individuation by reason of its incommunicability and nonreceptibility in matter, it too cannot be conceived inadequately as universal. This is especially so because what belongs to something per se cannot belong to it oppositely even per accidens. Therefore, since incapacity for multiplication belongs to it by the very character of its nature, multiplicability into many cannot belong to it even per accidens and by reason of an inadequate concept, as is required for a species predicable of many.

The reply is that angelic nature is in a category in itself with regard to the coordination of higher and lower degrees, for in itself it is a quiddity composed of genus and difference. But for this species to have a universality predicable of many does not pertain to the reason for placing it in a category, but to a condition or mode of the thing placed in a category. It is not incompatible with angelic nature to have such a mode by being conceived inadequately and after the manner of a corporeal thing; the nature itself, however, supplies the basis for this.

To the second objection the reply is that designated matter is a determinate and designated principle of individuation, not a remote one; universal nature must abstract from this designation. Universal nature does not abstract from matter itself, which is the remote principle of individuation. So, in an angel, the lack of matter and nonreceptibility in it, insofar as it contributes to the character of spirituality and of a simple form in the angel, is not the proximate but the remote principle of individuation. But insofar as it grounds subsistence and an ordering toward extrinsic accidents that designate the nature itself in the individual, it is the proximate principle of individuation, and angelic nature, conceived universally, abstracts from this. And to the claim that if something belongs per se to a thing, its opposite cannot belong even per accidens, the reply is that not belonging is one thing, and not being incompatible in some respect is another. Multiplication in several individuals does not belong to angelic nature positively and simply in any way; nevertheless, it is not incompatible with that nature by the force of the nature conceived indifferently. Therefore, by the force of the nature as such, it can be predicable of many—not positively, but by nonrepugnance.

But if you say: then such a nature is not universal logically, but metaphysically, because logical universality comes about through a positive comparison with many; whereas angelic species is not positively universal and cannot be compared with many except fictitious ones; therefore it is not logically universal.

The reply is that angelic nature has a logical intention—not one that actually compares it positively to many by reaching them, since they are only fictitious, but one that actually reaches one individual positively and many by nonrepugnance. This suffices for the relation of a logical intention. Thus, according to St. Thomas’s view, 3 p., q. 35, art. 5, one relation of a father regards several sons if they actually exist; but if there is only one son, in fact it does not reach several. Still, the relation that positively reaches one does not incompatibly reach several, because it is such that, if several were given, it would reach them. So too that relation of the specific nature regards one individual in such a way that of itself it could reach several, if they existed, so far as the force of that concept is concerned.

This difficulty is related to the preceding one, and from it we understand more fully how a species can be predicable of many, even if they are not possible because of the mode of individuation. Since two things are considered in both genus and species—namely, the nature they actually express and the many things to which they are in potency—it is certain that both genus and species, with respect to the nature they actually express, can be preserved in one species and one individual. For genus communicates its whole essence to each inferior; therefore the whole nature of genus and species is preserved in each. Hence St. Thomas says in Summa theologiae I, q. 77, art. 1, ad 1, that “the universal whole is present to each according to its whole essence and power, as animal is present to human being and horse.” Therefore the whole essence of genus is preserved in each species.

THE WHOLE DIFFICULTY is thus reduced to this: can genus, with respect to the potentiality and order it has toward many, be preserved with respect to one species, even if the others were impossible? For if they are possible, even if they do not in fact exist, it is certain that the genus's potency toward them is preserved, since it does not depend on their existence. In fact, after Judgment Day, in the whole genus of animal there will be only one species, human being; and this could also have happened from the beginning. We speak similarly of species according to its potency and aptitude to exist in many. The question is not about the intentions themselves, but about the aptitude and potency for many, which is their foundation. For an intention is a relation that follows the nature of its foundation.

Some therefore judge absolutely that genus can be preserved in one species and species in one individual. The reason is the same in both cases, because both are equally universals, and a universal is one in many. Therefore, if multiplicity for a species suffices only on the side of the mode of conceiving, although not on the side of the thing conceived, as we said in the preceding article, the same will suffice for genus. Others, on the contrary, think that neither genus nor species can be preserved in only one inferior, because it is essential to each universal to be divided by many differences, since it is one of many; therefore, if the many are lacking, the universal is lacking. Finally, others distinguish between genus and species: to preserve genus as a potential whole, they think many species are required; but to preserve species, many individuals are not required. On these opinions see the Carmelite Course, disputation 6, question 2.

This last opinion is more common and is undoubtedly St. Thomas's in his commentary on Posterior Analytics I, lect. 12¹, where he says: “It is not possible to find a genus of which there is only one species. For genus is divided into species by opposed differences. But if one of two contraries is found in nature, the other must also be found, as is clear from the Philosopher in On the Heavens II²; therefore, if one species is found, another is found as well. A species, however, is divided into different individuals by the division of matter. It can happen that the whole of the matter proportioned to some species is comprehended by one individual, and then there is only one individual under that species.” The holy Doctor teaches the same in Sentences I, dist. 19, q. 4, art. 2, body³.

THE BASIS of this opinion is drawn from two propositions set down by St. Thomas. First, genus is divided by opposed differences. Second, if one opposite or contrary is found in the nature of things, the other is found as well.

The first proposition is clear, because genus is contracted by formally diverse differences, that is, by forms incompatible with and distant from one another in the same genus. But opposition or contrariety consists in there being forms distant from one another in the same genus; if they are maximally distant, the contrariety is perfect. That genus is divided by formally diverse differences is clear because genus is divided by differences that contract it to constitute a species. Therefore, genus must express a nature capable of being actualized and contracted by formal differences that complete its actuality and formally constitute its essence. Hence, if it has several differences, they must be formally, not merely materially, diverse—that is, diverse in the very formal notion of quiddity—and therefore they must be opposed, as formally incompatible.

The second proposition is proved by St. Thomas himself in On the Heavens II, lect. 4⁴, because contraries have the same matter and subject; otherwise they would not expel one another if they did not concern the same subject. Therefore the matter or subject of one contrary must have potency for the other contrary. If, then, one contrary exists in the nature of things, the other is also possible, because there is a potency capable of receiving it. If it were impossible, this very fact would destroy the receptive potentiality for it in matter or genus, since there would be potentiality to receive only one. Thus the genus's potentiality for many would be destroyed, since it is for many as contraries and formally opposed things.

From these propositions the difference between genus and species is clearly deduced. Genus is related to specific differences as potential matter to actual and formally opposed or incompatible forms. Species, however, expresses an order toward many things that differ only materially and are incompatible only materially. Thus it is not related to individuating differences as matter to form, but rather as form to material division. What functions as matter, if it is communicable to many, must presuppose the possibility of those to which it is communicable. But what functions as form is communicable to many through the very character and concept of form, even if communication can be impeded by a defect in the receiving matter. The reason is that matter, and what belongs on the side of matter, is rather a principle of incommunicability in itself, just as it is a principle of limitation and restriction. But since matter is the ultimate subject, beyond which there is no communication, if matter is communicable to many, this is because those many are possible in relation to such matter. Thus the potentiality of matter for many is taken from the possibility of forms in relation to some subject or matter. If matter is communicated to form, this is more so that it may be perfected in itself by form than that it may communicate itself, since communicating itself is proper to the good. Matter, however, is not good in actuality, since it is neither perfect nor actual; and, as St. Thomas says in Summa theologiae I, q. 5, art. 3, ad 3, prime matter is not appetible but appetitive. Hence form desires matter not so much as matter, but rather to be in matter.

Therefore, for matter to be communicable to many means nothing other than that it can be actualized and perfected by many. Thus the potentiality of matter or genus for many arises from the plurality of forms that can perfect it. Form, by contrast, by its very character as form—which is act and perfection—is communicable to many insofar as it itself is concerned: for it is perfection and act, and perfection is good; good, as good, communicates itself. Therefore its communicability in itself does not depend on there being many recipients; it has this from the character of form and act. Hence St. Thomas says in On Interpretation I, lect. 10⁵, “every form that is naturally apt to be received in matter is, in itself, communicable to many matters.” And in Summa theologiae I, q. 3, art. 2, ad 3, and his commentary on Metaphysics VII, lect. 15, § Ponit aliam rationem⁶, he says universally that “any form, considered in itself, is naturally apt to exist in many.” Since species is taken from form and, by the very mode of conceiving it, expresses an essence formally complete, it is not incompatible to conceive it as communicable to many, even if, because of a defect in the receiving and materially dividing matter, it cannot always be communicated in actual exercise, as we said in the preceding article concerning angelic species. Therefore, species as such, even with respect to its communicability to many, does not depend on many individuals; genus, however, depends on many species.

THE ARGUMENTS ARE ANSWERED.

First it is argued to prove that genus can be preserved in only one species: in one species alone one can take an indeterminate and potential degree or character, and an actual and determinate character or degree; therefore genus and difference can be taken.

The antecedent is clear, because that species would be in a category, since it would be a created thing. Therefore it would have a higher and lower degree and, consequently, something determinable and determinate, since not all its predicates would have equal actuality and determination.

THE REPLY is that the species would indeed be in a category by reason of its limited nature and would have a higher and lower degree—not by a greater and wider superiority with respect to inferiors, but as less determinate and actual, or more potential, on the side of quiddity than the contracting difference. Thus it would not be universal generically, although it would have a nature more potential than the difference, as genus does. Its potentiality, then, would concern only one form, not be indifferent to many, as the potency of a soul or angel to receive intellect; this is not a potentiality for many, but only for one.

When it is objected that this generic predicate would not be equal to the specific and differential predicate, and therefore would be superior to them as genus:

The reply is that it would not be equal in actuality, because the difference would actualize it, but it would be equal in extension, because it would not extend to more things than species and difference. Generic universality, however, requires extension to many in the character of a potential whole, even though the nature it expresses is more imperfect and potential than the contracting difference in the character of quiddity.

Second it is argued: If the whole potentiality of genus could not be preserved in one species, then neither could it be preserved in two, ten, or any other definite number, because there is no greater reason why that potentiality should be exhausted by two species than by twenty or a hundred. Thus every genus would require infinitely many species, and the whole potentiality of genus could not be preserved, by absolute power, in one or two species, even though the whole potentiality of matter can be satisfied by one incorruptible form. Indeed, on this reasoning it would follow that species could not be preserved in one individual either, because it is in potency to many individuating conditions, which cannot all be preserved in a single individual. Therefore, just as genus is not preserved in only one species because it is in potency to many differences, neither is species preserved in one individual, because all individuating conditions cannot be gathered into one.

THE REPLY is that the potentiality of genus is preserved sufficiently by the very fact that it has many species, whether their number is determinate or infinite, for we are not discussing that. Therefore, at least two species under one genus are required and suffice; and, for the reason given, its extensive potentiality cannot be preserved, even by absolute power, with respect to only one species.

As to the example of matter, we say that either this matter is capable of many corruptible forms or it is capable of only one incorruptible form, as many think of the matter of heaven. If the latter, the potentiality of contrariety and extension to many is not preserved in that matter, but only the potentiality for actualization and informing, which occurs through one form. If the former, that matter always remains in potency to many forms by which it can be informed, even if in fact it is not in a state of change toward them, when it has an incorruptible form by which it is satisfied with respect to changing into other forms, though not with respect to its capacity for them.

As to the example of species in relation to many individuals, the reply is that it is true that one individual cannot have all the properties and individuating differences of a species, if they are in fact possible; but in one individual it has a nature which, by the concept of form and act by which it is constituted, is not incompatible with being communicable to many individuating differences, even if those differences are impossible because of a defect in matter. Genus, however, by being in one species, is not communicable to many species if those species are impossible, because matter is not in itself a principle of communicating to many, but of receiving many. Therefore, if those are impossible, the potentiality to receive them does not remain. The same applies to genus, whose potentiality is assimilated to matter in its relation to forms or formal differences.

Finally it is argued: If a species is preserved in one individual, it either has an incompatibility with many essentially attached to it or it does not. If it does not, then those many are possible, and thus the supposition that only one individual is possible is removed. If it has an intrinsic incompatibility, then it cannot, even according to the mode of conceiving, be taken as communicable and universal to many; thus there would be no difference between it and genus.

It is confirmed: In that case species and individual are not distinct, since only one individual is possible. Therefore the indifference to many required for the universality of species is not preserved in it. Or, if indifference is found because it is a higher predicate, we will say the same of a generic predicate in only one species.

THE REPLY is that even if species has an incompatibility with many individuals essentially attached to it, its character of universality can be preserved, if it has that incompatibility not from the concept of its nature as nature, but from its mode of individuation, which is contained radically in the specific nature itself, as we said in the preceding article. Thus, it is not incompatible to conceive such a nature inadequately and under the precise concept of nature and form as communicable to many, since that precision and inadequate concept do not entail incompatibility, even if in reality it is incompatible on account of another principle that also pertains to the essence itself, namely, that it lacks matter in whose different parts a different individual nature could be received.

To the confirmation, the reply is that this specific nature is distinguished by reason alone from that one individual. Nevertheless, it is said that indifference and potentiality for many fundamentally remain in such a species, but not in genus—not only because it is a higher predicate, but because it is such a higher predicate, namely, by way of a formal quiddity which, according to the properties of form, is communicable to many from the very concept of form and nature, even if there are no things to which it could be communicated. Genus, however, by the force of its precise concept, does not express communicability to many as form does, but as matter does; unless many forms are possible, it has no potentiality to receive them.

From this the other objection is also resolved: how can species, being a potential whole with respect to individuals, be preserved in only one individual, which is a part of it, since every whole is greater than its part?

The reply is that species existing in only one individual is a potential whole not only with respect to that individual, but with respect to many, to which it is not incompatible to be communicated by the force of its formal concept, even if in reality many things to which it could be communicated are not possible. Therefore we do not say that species is preserved with respect to only one individual, but that species existing in one individual is not incompatible with being conceived as communicable to many, insofar as this follows from the mode of conceiving that form or nature.