Disputationes metaphysicae

1. We have shown that there is individual and singular unity in things; now we begin to declare what it is, which cannot better be done otherwise than by declaring what it adds over the common nature, or that which is abstractly and universally conceived by us.

Various opinions are reported

2. The first opinion generally affirms that, at least in created things, the individual adds to the common nature some real mode distinct from the nature of the thing from the nature itself and composing with it the individual itself. This seems to be the opinion of Scotus, In II, dist. 3, q. 1, and in the Quodlibet, q. 2, and Metaphysics VII, q. 16; and in the same place Antonius Andreae, q. 17; which opinion Fonseca seems to defend, Book V, q. 3, sect. 2, and q. 5, throughout. And John Baptist Monlorius fights most keenly for it in his special work on universals, c. 6. The foundation of this opinion can be almost that which (on Aristotle’s testimony) moved Plato to posit ideas of universals abstracted from singulars, namely, because sciences and demonstrations are of universals and not of singulars. Likewise, because essential and proper definitions are given of universals and not of singulars. Likewise, because the properties which are per se in things belong to them by means of the universal natures, so that it is true to say that Peter is risible because man is risible; just as conversely contingent predicates belong to common natures by reason of individuals; for man runs because Peter runs; therefore all these indicate some distinction from the nature of the thing between the individual and the common nature; but this distinction cannot be except in so far as the individual adds something over the common nature, because it includes that whole; therefore it cannot be distinguished from it except as something adding to it.

3. Secondly I argue: because man, for example, is not essentially something individual; therefore, when he becomes individual, something is added to him outside the essence of man; therefore it is necessary that that be distinct from the nature of the thing from man as such. The antecedent is evident, because if man were essentially this individual, he could not be multiplied into several; indeed neither could he be conceived without some individuation and singularity, because a thing cannot be conceived without that which is of its essence; but man can be conceived distinctly, indeed also defined essentially, without any individuation. Just as God, because he is essentially this singular individual, therefore can neither be multiplied nor truly and properly conceived unless he is conceived under this individual and singular notion. But the first consequence seems self-evident, because to be individual is something in the nature of things, and that is not essential to the common nature, indeed not even to the individual itself (as is commonly said), because all individuals are of the same essence; therefore it is necessary that it add something besides the common essence. And hence the second consequence is easily proved, because what is of the essence and what is outside the essence seem to be distinguished from the nature of the thing; indeed those things are most of all so distinguished of which one is not of the essence of the other; but what the individual adds to the species is outside its essence, as has been shown; therefore.

4. Thirdly, Peter is not formally constituted as Peter and as man by the same thing; both because that by which man is constituted is common to Peter himself and to other men, but that by which he is constituted in the being of Peter is proper to him; and also because otherwise man could not be conceived under a common concept any more than Peter. And here can be added all the arguments by which it is wont to be proved that universals are distinguished from the nature of the thing from their inferiors, which we partly touched upon above in dealing with the concept of being, and shall partly touch upon in the following disputation.

5. The second opinion, extremely contrary, is that the individual adds nothing at all to the common nature which is positive and real, or distinct from it either in reality or in reason, but that each thing or nature is per se individual primarily and immediately. So think the nominalists, In I, dist. 2, where Ockham, qq. 4 and 6; and Gabriel, qq. 6, 7 and 8; this opinion can also be attributed to Henry, Quodlibet V, q. 8, where he thinks that the individual adds to the species only a negation, of which opinion we shall say more in the following section, opinion 3. The foundation is that nothing real can be understood which is not singular, as was proved in the preceding section; therefore it is repugnant that a thing become singular through the addition of something real over the common nature. Secondly, because no thing can become one through the real addition of something positive, as was shown above; therefore neither singular and individual. The consequence is evident, both because singularity is a certain unity, and also because there is no true and real unity besides singular and individual unity. Thirdly, because what is added is either essential or accidental; if essential, it follows that the species can be divided through essential differences, against Porphyry, chapter on Species; whence it further follows that individuals differ essentially, and that the species does not express the whole essence or quiddity of individuals, which is against Porphyry and all dialecticians. Finally, it follows that individuals can and must be defined by a proper and adequate essential definition, against Aristotle, Metaphysics VII, text 53. But if what is added is accidental, it follows that the individual is being per accidens; it follows also that accident does not come to an individual subject but constitutes it, which is impossible, because if one is individuated from the other, rather the accident receives individuation from the subject than conversely.

6. The third opinion can use a distinction between spiritual and material things; for in immaterial things the singular thing adds nothing over the common nature, but in material things something. Which distinction seems founded on Aristotle, Metaphysics VII, c. 11, text 4, where he says that in immaterial things the quod quid est is not distinguished from that whose it is, but in material things it is distinguished; where by quod quid est he understands the essence or essential definition, which can be compared both to the thing defined itself and to the individuals in which such a thing defined and definition exists. In the former way Aristotle compared them, Metaphysics VII, c. 6, texts 20 and 21, and generally taught that in beings per se the quod quid est is the same as that whose it is, or the definition as the thing defined, because they express the same essence and differ only in the confused or distinct mode in which they are conceived. Which is common both to simple and composite substances and to accidents, if they are defined in so far as they are one per se. For beings per accidens either cannot be defined by one definition, or, if they are in some way defined after the manner of one by reason of the accidental form, that definition is in some way distinct from that subject to which it is attributed. In the latter way, however, which pertains to the present point, they are compared by Aristotle in the other place cited, and in this way he says that in immaterial things the quod quid est, that is, the specific essence, which is explained by the definition, is the same as that whose it is, that is, as the individual or singular thing; which he says is otherwise in things composed of matter and form. He thinks, therefore, that the immaterial thing is individual by itself without any addition, but the material not so, but becomes this individual through some addition; and so St. Thomas and others expound this place. And in De Anima III, text 9, Aristotle says that in certain things the thing, supply individual, is other than the specific quiddity of the thing, which he himself says in those words: Magnitude is one thing, the being of magnitude another; but he adds that this distinction is not found in all things, which all expositors understand to have been said on account of immaterial things, in which individuals are nothing but the specific natures themselves subsisting. So Averroes, Philoponus, and at length St. Thomas. Whence the same St. Thomas seems to teach this opinion, I, q. 3, a. 3, and De ente et essentia, c. 5, in which places Cajetan, and III, q. 4, a. 4, thinks the same, and it seems to be the received opinion in the School of St. Thomas, as will be more evident from what we shall report in sect. 4. For from what is to be treated there the foundation of this opinion is to be taken, namely, because immaterial substances, since they neither have matter nor express a relationship to it, nothing too can be thought out in them which they would add over the essence, and therefore they are individual by themselves; but in composite things signate matter is added, from which something can be taken which the individual adds over the species.

The point of the difficulty is laid open

7. First, it is undoubted among all authors that the individual adds over the common nature some negation formally completing or constituting the unity of the individual. This is self-evident from the notion of unity explained above, adding the things which we noted in the preceding section about the notion or meaning of the name of individual. Rather, if we speak formally of the individual in so far as it is one in such a way, it adds a negation in its formal concept not only over the common nature abstractly and universally conceived, but also over the whole singular entity precisely conceived under a positive notion, because this whole entity is not conceived as one singularly and individually until it is conceived as incapable of division into several of the same notion. The present difficulty, then, is not about this negation, whether it formally pertains to the notion of this unity or not; for about this too there are opinions, of which we have already said in the preceding disputation what we think truer; but the difficulty is about the foundation of that negation; for, since it does not seem able to be founded in the common nature alone—for that of itself is indifferent and does not postulate such an indivision into several similar ones, but is rather divided in them—we therefore inquire what there is in the singular and individual by reason of which such a negation belongs to it.

Resolution of the question

8. I say, first: the individual adds something real besides the common nature, by reason of which it is such an individual and that negation of divisibility into several similar ones belongs to it. In this conclusion we agree with Scotus, and it is taken from St. Thomas, I, q. 40, a. 2, saying that wherever there is something common to many there must be something distinctive. And Contra Gentiles I, c. 42, seventh reason, he says that that distinctive must be something added to the common intention. And the Thomists do not dissent from this conclusion, as is evident from Cajetan, Posterior Analytics I, c. 4, De ente et essentia, c. 4; Soncinas, Metaphysics VII, q. 31; Capreolus, In II, dist. 3, q. 1; Hervaeus, Quodlibet III, q. 9; Soto, on the Logic, q. 2 on universals. And it is proved from what we have just said; for the common nature of itself does not postulate such a negation, and yet to that nature, as it exists in the thing and has been made this, such a negation belongs per se and intrinsically; therefore something has been added to it by reason of which it has been adjoined to it, because every negation belonging intrinsically and necessarily to some thing is founded on something positive, which cannot be of reason, but real, since that unity and negation truly and of itself belong to the thing itself. Or this reason can be proposed otherwise, because the specific nature according to itself, and in so far as it is the proximate object of the common concept of man, lion, etc., has nothing repugnant to communicability, and therefore is said to be negatively indifferent, as we shall see below; but through this individuation this indifference of it is taken away and it becomes incapable of such division, in so far as it has been made singular; therefore it is necessary that something positive be understood to have been added to it, by reason of which this is repugnant to it. Finally, Peter and Paul agree in the common nature and differ among themselves in their proper notions; therefore they add these to the common nature; but these are positive; for they are not constituted by negations in the notion of such a substance; therefore. The arguments which were adduced to confirm the opinion of Scotus also conclude the same.

9. I say, secondly: the individual as such does not add something distinct from the nature of the thing from the specific nature, so that in the individual Peter himself, for example, humanity as such and this humanity, or rather that which is added to humanity in order that it become this (which is wont to be called haecceity or individual difference), are distinguished from the nature of the thing and consequently make a true composition in the thing itself. In this assertion all who attack the opinion of Scotus must agree, such as Cajetan, De ente et essentia, q. 5, and I, q. 5, a. 6; Soncinas, Metaphysics VII, q. 3; Nifo, Metaphysics IV, disp. 5, and others. Who nevertheless do not sufficiently distinguish whether they attack Scotus as regards his whole opinion, even as regards the addition of the individual difference over the specific, or only as regards the distinction from the nature of the thing, and their arguments seem to be common to both parts, and therefore are not very efficacious. In the same assertion those must necessarily agree who deny that the nature is universal in reality, as are the weightier philosophers and theologians, and the whole school of St. Thomas, as we shall see in the following disputation. But that one follows from the other is evident, because, if in the individuals themselves that which the individual adds over the common nature is distinct from the nature of the thing from it, then conversely the nature itself in the thing itself prescinds from such an addition or individual difference; and so in reality nature and haecceity are two, if not as two things, at least as a thing and a mode; therefore each of them has per se its own unity, because it cannot be understood that some things are two unless they are one and one; for number supposes unities; therefore that nature, as prescinded from the individual difference, has unity in the thing itself; therefore either individual unity or universal. The first cannot be said according to the aforesaid opinion; otherwise the nature would be individual before the individual difference, and so such a difference would be superfluously adjoined; therefore according to this opinion it must necessarily be said that that nature, as it prescinds in the thing itself and is distinguished from the nature of the thing from the individual difference, has universal unity; which it can be understood from what was said in the preceding section is impossible, and we shall show it more fully below.

10. It can be answered, according to the doctrine of Scotus, that the nature as prescinded in the thing from individuation has neither individual nor universal unity, but formal unity, which is as it were intermediate between the aforesaid unities, and is nothing other than the unity of the essence which is explained through the definition. But against this, first, because, although in such a nature this formal unity can be distinguished by reason from individual unity, it nevertheless cannot be conceived that in reality it is according to its entity prescinded and distinct from the nature of the thing from individual unity, and that as such it also lacks universal unity. It is proved, because either that as such is common or incommunicable; for these two are immediately opposed; if incommunicable, it is individual; if common, it is universal. Likewise, either that nature which in Peter is distinct from the haecceity of Peter is by itself really distinct from the nature which is in John, as it too is distinguished in him from the nature of the thing from his haecceity, or as such it is not distinct; if this second is said, that nature will be common; but if the first is said, it is necessary that those natures as such be individual and singular, because they differ only as distinct in number and really within the same species.

11. And hence I argue, secondly, directly showing that there cannot be such a distinction in things which would be a true and actual distinction from the nature of the thing preceding every operation of the intellect; for every such distinction must be between real entities, or between a real entity and its mode. And indeed, if it is in the former way, it will be a real distinction, which will necessarily suppose each entity as singular and individual in itself, which is self-evident and so is denied by no one, because the distinction of entities supposes each entity constituted in itself and thus one and singular. But if the distinction is between an entity and its mode, as it is here said to be, in order that it be a true distinction from the nature of the thing it is necessary that such an entity, the mode being prescinded, be understood to have in the thing itself a true real entity; otherwise a distinction from the nature of the thing between such a mode and entity could not be understood. Because either that mode intrinsically and formally constitutes that entity or not; if it constitutes it, then it is not distinguished from the nature of the thing from it, because it will be intrinsically and essentially included in it, so that nothing can be conceived in that entity which does not include that mode; but if that mode is not understood so intrinsically and formally to constitute such an entity, it is necessary that it be understood to suppose it constituted in its entity and really to come to it and modify it, since it is posited as distinct from it in the thing itself. But it is impossible to understand this mode of distinction between the individual difference and the common nature; therefore. The minor is proved, because, if, that mode being prescinded, the nature is understood to have its entity, then that entity by itself, and as it is prior to that mode, must necessarily be singular and individual; therefore it does not need a superadded individuation, nor can it be distinguished from the nature of the thing from it; just as, if a line could not be understood constituted in the notion of line without straightness, straightness could not be conceived as a mode co-distinct from the nature of the thing from the line and coming to it; but if now it is conceived as a mode distinct from the nature of the thing, it is because the line can be conceived existing in the thing itself and constituted in the notion of line without such a mode.

12. But the first consequence is proved, because every entity existing in things must necessarily be singular and individual by itself: first, because as such it is understood to be outside its causes and to have real actuality and existence; therefore as such it is understood as singular, because nothing can terminate the action of causes or be capable of existence unless it is singular. Secondly, because such an entity, as so conceived prior to a mode distinct from itself, is incommunicable to many inferiors or to things of the same notion, because it can neither be divided from itself nor become several; therefore already as such it is individual. Thirdly, because that mode of haecceity which constitutes Peter is singular and proper to him and is said to constitute and compose Peter by modifying the nature; therefore, if that modification is through a true distinction and composition which is in the thing, it is necessary that to that mode, which is as it were a certain particular act, there correspond also a particular entity after the manner of an actuable potency; therefore that entity which is supposed to such an act must be individual and particular. Which is explained, fourthly, for in Peter and Paul, for example, there is a double composition from common nature and individual difference; therefore in both there is really distinct not only the individual difference of one from the individual difference of the other, but also the entity of the nature which is in one from the entity of the nature which is in the other; therefore those two natures are distinguished intrinsically and entitatively as two singular things, even when the individual differences are prescinded by the intellect, because a real distinction between actual entities cannot be understood except in so far as they are individual and singular.

13. You will say that they are indeed distinguished through the individual differences, as two matters are said to be distinguished through forms or quantities. But of this example we shall speak afterwards; for universally I think it cannot happen that one thing is really distinguished from another through something else distinct from itself, but through its own entity, through which it is constituted in such being, because, proportion being kept, a thing is distinguished by that by which it is constituted. But in the present case this is manifest, because in Peter and Paul there are two individual differences really distinct among themselves, and each of them actuates a real nature, from which it is distinguished from the nature of the thing and with which it composes its individual altogether really distinct from the other, not only as regards the difference, but also as regards the whole entity of the nature; therefore it is necessary that, even when the differences themselves are prescinded by the intellect, that which remains in reality in Peter and Paul be really distinct and therefore singular; otherwise it would have to be said that some thing altogether really the same is contracted by individual differences in Peter and Paul. For it is not enough to say that not the same nature really, but the same formally, is contracted; for this formal identity, as it can be in the thing, is only a certain likeness, which supposes real distinction, and consequently the individuation of those things which are called similar; but as it is conceived after the manner of unity, it is not real unity, but only of reason, by denomination from the concept of the mind, as we shall say afterwards.

14. Fifthly, this can be declared, because the individual differences themselves of Peter and Paul are really distinguished among themselves as two incomplete things, yet singular and individual in the way in which they are, and nevertheless have among themselves likeness and agreement, because in truth they are more similar among themselves than to the individual difference of a horse or lion; and in them it would not be necessary to distinguish from the nature of the thing something in which they are similar and something in which they are distinguished; otherwise one would proceed to infinity, which in things or modes distinct from the nature of the thing is an inconvenience, as was said above in a similar case; therefore the same could be said of the individuals Peter and Paul themselves, that, although they are distinguished among themselves and are similar, it is not necessary to distinguish in them from the nature of the thing that by which they are similar and that by which they are distinguished; therefore there is no reason why the individual difference should be distinguished from the nature of the thing either from the common nature, as from an extreme composing the individual, or from the whole individual, as from an integral composite. Nor does it matter if someone answers that those individual differences are simpler and are that by which individuals are constituted and distinguished, and therefore can more be distinguished by themselves; because, although perhaps as regards distinction of the concepts of the mind this contributes something, as I shall say immediately, nevertheless, if this distinction were in things, the argument would urge, because those differences are to be considered as two real modes existing in reality and distinct from the nature of the thing from any other entity whatever; because, just as they have quasi-formal effects distinct in number, namely to constitute this or that individual, so also they are distinct in number. And although they are by which with respect to the individuals, nevertheless, in so far as they are in themselves something and real beings, although incomplete, they are also which, at least incompletely, as we noted above in a similar case in treating of the concept of being, as Cajetan also noted, I, q. 11, a. 1, around ad 1. And yet with this distinction and simplicity they have among themselves a real agreement in the common notion of such modes, as the same Cajetan says, De ente et essentia, q. 5; therefore either in these too the common notion is to be distinguished from the proper ones, or certainly such a mode of arguing is fallacious in any individual whatever. Some answer that between these individual differences there is no real agreement from which a common concept could be abstracted; but this is difficult to believe, of which it will be said generally in the following disputation.

15. And hence a sixth reason is taken, because that whole distinction which is feigned to be from the nature of the thing between the nature and the individual has been taken from the mode of conceiving and speaking, from the agreement and distinction which is found between the individuals themselves; but this is no sign for indicating a distinction from the nature of the thing, and on the other side there are many things which more urgently indicate that there is no such distinction in the thing; therefore. The major is evident from the arguments made in favour of Scotus. The minor as regards the first part is evident, both from the example adduced of the individuating differences themselves, and from what was treated above about the concept of being, about which almost the same arguments are made; and also because otherwise it would be necessary to distinguish from the nature of the thing all common concepts from particular ones, which I shall show below to be false. Finally this part will be more fully evident from the solutions of the arguments. But the other part of the minor has been sufficiently proved by the arguments made. Which is finally confirmed from the sign of inseparability; for those things which, although they are conceived by us in a diverse way, are so related in the thing that neither is separated or can be separated from the other even by absolute power, are without cause feigned to be distinct from the nature of the thing, as I shall say more fully below in the disputation on distinctions; but the notion of man and the proper individuation of Peter are so related in Peter that they can in no way be separated, neither such a mode from the nature, nor the nature as it is in Peter from such a mode; therefore. Nor does it help at all to say that the notion of man is separable from Peter because it can be in Paul, because this is not to consider the notion of man as it really exists, but only as it is conceived in the mind, and therefore it is not enough for a distinction from the nature of the thing, which must be between those things which are in reality, if it is a distinction between positive things, or between a thing and a real positive mode. Whence that distinction which is understood between the common notion abstractly understood and the individual is only of reason, because that nature as such is nowhere except objectively in the mind. But if anyone calls that a formal distinction, because the mind conceives one definition of man as such and another of Peter, he will raise a question about a word; because, as regards the thing, that distinction is not so in the thing that in Peter or Paul those things are understood to be distinct from the nature of the thing, or to make a composition in the thing, as has been shown.

16. I say, thirdly, that the individual adds over the common nature something distinct from it by reason, pertaining to the same predicament, and composing the individual metaphysically, as an individual difference contracting the species and constituting the individual. The first part of this assertion follows from the two preceding ones; for it was said in the first that the individual adds something to the common nature, and in the second it was denied that that is distinct from the nature of the thing; therefore it is necessary that it be distinguished at least by reason, because, if it were in no way distinguished, it would in no way be added. Nor does it follow from this that what is added is something of reason; for, just as it is one thing to be distinguished by reason, another to be only of reason—for it can happen that things which are real are distinguished by reason alone—so also what is added can be real, as it truly is, although it is distinguished by reason alone. You will say: that addition is only through reason. I answer: as regards the thing added I deny it; as regards the mode of addition, or of contraction or composition, I concede it; for, just as the separation of the common nature from the individual differences is only through reason, so conversely that the individual difference is understood as added to the common nature is only through reason; for in the thing there is not that proper addition, but in each individual there is one entity really having by itself each notion.

17. The second part of the conclusion also follows openly from what has been said, and it is taken from St. Thomas, I, q. 29, a. 1, where he says that substance is individuated by itself; and De potentia, q. 10, a. 3, he denies that substance can be constituted by an accident; this addition, therefore, is not outside the genus of the thing itself, but in substances it is substance, at least incomplete, because in the thing there is nothing but individual substance. The third part, finally, is easily evident, because this addition is not some physical part of the substance, because it is predicated of the individual as expressing its whole essence, which a physical part does not express, and therefore it is not predicated of the whole. Nor is it something after the manner of a whole directly placed in the predicament of substance; it is therefore something incomplete after the manner of a difference. Likewise it contracts the common nature and divides it into individuals, and constitutes the individual itself metaphysically, as per se one in its genus.

18. But against this conclusion a certain reason made in the preceding can be objected; for, if the individual adds something at least distinct by reason, there follows a process to infinity in objective concepts distinct by reason, which also above in a similar case we reckoned an inconvenience; the consequence is evident, because the individual is said to add over the species something distinct by reason because it agrees with another individual in the specific notion and differs in the individual one; but the individual difference itself too agrees with another similar difference in a common notion, and differs in number from it; therefore it too adds according to reason something distinct by reason over the common notion of such a difference; and again of that addition the same argument will be made, and so to infinity. It can be answered, first, that in these our concepts it is not a great inconvenience to admit a process of this kind, because the intellect divides things which in reality are altogether indivisible, and therefore it would not be wonderful if the intellect could proceed to infinity in these divisions or concepts. Secondly, someone could so philosophize about the concept of species and individual as we reasoned above about the concept of being and its inferiors; for we said that the inferiors add over being something distinct by reason, yet in such a way that the inferior concept immediately conceived under the concept of being is not properly resolvable into two concepts, but is only a simple concept more express and determinate than the concept of being; so, then, in the present case it can be said that the concept of the individual is not properly composite and resolvable into the concept of another mode, or of an individual difference, but is only a more express concept of the specific nature itself as it exists in the thing in such an entity, in which neither can such an entity nor anything of that entity be conceived without including such a specific notion, nor can the specific notion itself, as it exists in the thing, be distinctly conceived except as contracted in such or such an entity. And by this reason the process to infinity is easily avoided, as is evident from what was said in a similar case of being.

19. But this mode of answering can seem little consonant with the common mode of conceiving and speaking of the philosophers, who explain this contraction of the species to individuals after the manner of metaphysical composition. And not without reason does this seem to be commonly affirmed, because genus and difference too are not distinguished in the thing in which they are conjoined, as we shall show below, and nevertheless, on account of the various agreements and disagreements which are found between several things, the intellect forms diverse concepts of genus and difference, of which one is not included in the other; so, then, it can also do between species and individuals; for their proportion among themselves is almost the same, and the same the difference from the concept of being. For that is transcendent, and therefore cannot properly be contracted after the manner of composition, nor can anything be added to it according to reason in which it is not included; but the concept of the species (as also the concept of the genus) is of itself limited and not transcendent, and therefore it is not necessary that it be included in every concept determining it; it can therefore be contracted after the manner of composition, and consequently the individual can also be resolved into the concept of the species and of the individual difference; for that is not man, nor Peter, for example, but a difference contracting man and constituting Peter. You will say that there is also a difference between genus and species, because the generic notion, not only as abstracted and made universal in the mind, but also as existing in the thing itself, can be prescinded in the mind and distinguished by reason from the specific difference, as we shall see below; but the specific notion cannot be distinguished even by reason from the individual difference except as abstracted and made universal in the mind, because as existing in the thing it cannot be conceived except as including individuation; and because every composition, even according to reason, must be understood in the thing as it actually exists, therefore such a composition is more easily understood between the generic and specific notion than between the specific and individual. But notwithstanding this, that metaphysical composition of the individual is not to be denied, because for it it is enough that the specific notion can be prescinded in the mind as not included in this individual difference.

20. And therefore, that kind of composition and resolution of the individual being admitted, the answer, thirdly, is that it is not necessary to proceed to infinity; for the same mind which conceives the individual as composed of the objective concept of the species and the individual difference conceives the individual difference as altogether simple and irresolvable, because it does not conceive it under the concept of species, but only of difference, of whose notion it is to be simple and not composed of a common notion and another contracting difference. As can be seen also in the specific or subaltern differences themselves; for sensible or rational are not formally composed of other differences, but by the very fact that they are notions of differing, they differ from others by themselves; so, then, the individual differences too are to be conceived, in which as regards this that mode of determining being to themselves through simple determination of the concept without composition can be admitted. And that notion of the individual difference, in so far as it can be conceived as a real and common notion, will also be as it were transcendent to the individual differences, because nothing can be conceived in them in which such a notion is not included; and therefore that common notion too will be determined to the individual differences not through a new composition but through the simple determination of a more express and determinate concept, and so further resolution and process ceases.

21. I say, fourthly: the individual, not only in material things and accidents, but also in created and finite immaterial substances, adds something distinct by reason over the species. We exclude from this conclusion the divine nature, because, since it is essentially so determined to this nature in number that it is altogether repugnant to it to be multiplied according to it, the common notion of deity cannot even according to reason (if it be true) be abstracted from such a deity; for, by the very fact that it is so abstracted, true deity is not conceived, because it is of the true concept of deity that it be this in number and not another; because its infinity requires this. And hence it consequently comes about that this individual deity adds nothing even according to reason over the concept of true deity. Whence Cajetan is deservedly reproved because in I, q. 3, a. 3, and in other places, he said that God can in one way be taken as it signifies a concrete, as it were specific, of the divine nature. For such a truly common concept is repugnant to true divinity, of whose essence it is that it be this singular nature, and therefore the true God can no more be conceived by a common concept and abstracted from this God than Peter.

22. From this exception, however, which is singular and belongs specially to God on account of his infinity, the conclusion posited and the contrary general rule in all creatures, even if they are immaterial, is confirmed. It is proved, because in any immaterial, individual and finite substance, for example Gabriel the Archangel, the mind conceives both this individual, in so far as it conceives this entity in number, and its essential and specific notion, which does not essentially include this entity in number nor a positive repugnance to being communicated to another individual; therefore the mind there conceives something common and something which according to reason is added to it in order that it be determined to this individual; therefore as regards this precisely there is no difference between immaterial substances and other things. It will perhaps be said that any angelic essence or species whatever is essentially and intrinsically determined to this individual, and consequently that this individual adds nothing positive and real, even distinct by reason, over the species itself, but only the negation of communicability to several similar ones, which belongs immediately to such a species by reason of itself without any addition.

23. This indeed seems to have been the sense of the authors whom I cited in the third opinion, and the same think those who deny that angels differing only in number can be created within the same species, even by absolute power; for this cannot be denied to the divine power for any other reason except because it is judged to be against the intrinsic and essential notion of such a nature. That opinion, however, has a foundation in St. Thomas, I, q. 50, a. 4, and the question De spiritualibus creaturis, a. 8, and Contra Gentiles II, c. 95, De ente et essentia, c. 5, where Cajetan holds it, q. 9; and Capreolus, In II, dist. 3, q. 1, concl. 5; and Abulensis, Paradoxa IV, c. 34. And Aristotle seems to favour it much, Metaphysics XII, text 40; and Avicenna, Metaphysics V, c. 5.

24. But this opinion first of all supposes that signate matter is the adequate principle of that individuation in which the individual adds something positive to the specific notion, which can be called positive individuation; but this supposition in the aforesaid sense is false. The major is openly evident from the aforesaid authors. And its reason is clear, because they deny such individuation in the aforesaid substances for no other cause than because they lack matter; therefore they suppose that matter, either according to itself or as signed by quantity, is the adequate root of such individuation, so that from that principle, If affirmation is the cause of affirmation, negation is the cause of negation, they infer from the lack of matter the lack of the aforesaid addition or individuation. But the minor proposition will be proved at length in the following section, even in material substances. But even if we granted that in material substances an individual difference of this kind is taken from matter, it could not efficaciously be inferred that matter is the adequate principle of that difference in the whole breadth of created being; for diverse substances have diverse principles accommodated to their natures, nor can a sufficient argument be taken from the mode of composition or individuation found in exterior things to things of a superior notion; otherwise by the same reason someone could deny that there is in the angels a metaphysical composition of genus and difference, because in material things the genus is taken from matter and the difference from form, which many wish to be understood with propriety. Likewise with the same facility someone could say that in the heavenly bodies the individual does not add over the species something positive, even distinct by reason, either because they do not have matter, as Averroes thought, or certainly because they have matter of another notion. For if it is true that in these inferior things matter is the only root of the individual difference, we can only attribute it to this inferior matter; for of the superior we can gather by no sufficient reason whether this also belongs to it, since it is of a diverse notion. They will perhaps say that that matter underlies quantity of the same notion, and that this is enough for it to be the principle of the same mode of individuation. But this does not satisfy; for, as I shall show below, quantity, since it is an accident, can in no way enter into the principle of the individuation of substances. Substances of a superior order, therefore, can agree in metaphysical composition with substances of an inferior order, and have the principle of it in a simpler and more perfect way. And so from the negation of matter no efficacious argument can be made.

25. Next I return to the reason begun; for that the divine nature essentially includes its positive individuation and incommunicability with respect to inferiors comes precisely from this, that such multiplication is repugnant to its infinity; but every created immaterial substance is finite; therefore there is no reason why it should be repugnant to it to have another altogether similar essence, yet really distinct in entity. It can be answered that, although spiritual substance is simply finite in the genus of being, it is nevertheless infinite in its species and has the whole perfection possible in its species, because, since it is abstracted and separated from matter, it has nothing whence it is limited, and therefore cannot be multiplied within that species. But infinity of this kind is both asserted without sufficient foundation and can scarcely be declared in what it consists, except by begging the question.

26. I ask, then, whether this infinity is intensive or extensive. The first cannot be said, both because the whole intensive perfection of such an angel is contained within a certain grade and limit of such a species, in which there is no formal intensive infinity; unless perhaps it be said infinite in a certain respect, because it can contain under itself syncategorematically infinite species of an inferior order, which nevertheless does not indicate infinity, but a certain perfection of a superior notion; whence this can be common to the species of material things, as is evident in the human species, under which species of brutes can be multiplied to infinity. This genus of perfection or infinity, therefore, is nothing to the question with which we are dealing, nor can it be the reason on account of which some species is individual by itself and cannot be multiplied in individuals. Indeed, even if we admitted that intensive infinity, true and formal, in some intrinsically limited grade, it does not follow that such a perfection cannot be found in many similar individuals, because this has no necessary connection with that. As, although there were given an infinitely intense grace in the soul of Christ the Lord, for example, it does not therefore follow that there cannot be given other qualities of grace distinct in number, whether finite or infinite. Which argument also declares that that proper and formal intensive infinity can no more be given in substances than in accidents.

27. But if the discussion is of extensive infinity, first the question is begged, because this extension is nothing other than the multiplication of individuals in that species. Next, what is said involves a repugnance; for that individual formally and in itself is only one; how, then, can it contain in itself an extensive infinity, which consists in the mere multiplication of individuals? You will say that it contains it virtually, not formally. But it cannot be explained in what this virtual infinity or containment consists or in what it is founded, since it does not consist in the intensive infinity of such a nature, nor can it be founded in it, as has been proved; no reason, therefore, is assigned on account of which it is repugnant to the perfection of such a nature to be communicated to many individuals similar in essential perfection. Substances of this kind, therefore, although abstracted from matter, are simply finite. For it is not necessary that they have limitation from matter properly so called (whatever may be the case as regards this with material forms), but from their proper difference, or from themselves and from their proper entity, or because they have such a received being, or finally because by their nature they exist in such a supposit; from infinity, therefore, no reason can be taken on account of which immaterial natures of this kind are essentially individual and incommunicable.

28. It can be said otherwise that from immateriality alone a sufficient reason is taken. Because things which lack matter cannot be multiplied materially, as is self-evident; therefore only formally and essentially or specifically; therefore not individually or according to numerical multiplication, because this is material multiplication. But this reason too, if the words materially and formally are taken properly in the first antecedent, is insufficient and begs the question; for it takes the conclusion itself in the reason, namely either that numerical distinction is taken from matter, or that to differ in number is the same as to differ materially. For granted that in material things these have some truth, which we shall examine afterwards, nevertheless no sufficient argument can be taken thence to immaterial things. Individual distinction, therefore, extends more widely than material difference taken in the said way; for to differ in number is only to be distinguished in proper entities with agreement and likeness in the whole essential notion, which can be common both to spiritual and to corporeal things. Whence, if material and formal are taken more broadly, as formal expresses the precise essential notion, but material whatever contracts it and determines it to such an entity, then two angels of the same species, although they are distinguished as two integral forms, can be said to be distinguished not formally but materially or entitatively, as two rational souls are distinguished among themselves.

29. And by this example this opinion can first be confirmed; for the rational soul, physically considered, is also a simple and spiritual entity, and yet is not individual from its essential notion, but adds something according to reason. But they say that the rational soul has a transcendental relationship to the body, and is individuated thence. But this first of all is uncertain, for perhaps it is as true that this soul expresses such a relationship to the body because it itself is such, as conversely. And next, whatever may be the case with this, it matters nothing to the present point, for the same proportional argument can be taken; for the rational soul, which has its specific notion with a transcendental relationship to the body, does not have individuation by virtue of that precisely, but from some addition according to reason, through which that relationship is determined to such a body, or rather to such a relationship to the body; therefore in the same proportion the substance of an angel, which has an absolute essential notion without transcendental relationship, will not be individual by virtue of that, but from something added according to reason proportioned to it. And a similar argument can be taken from spiritual accidents, in which the individual adds something over the species not only in order to diverse subjects, but also with respect to the same; for these accidents can be distinguished in number and multiplied with respect to the same subject, at least successively, as is evident of diverse acts of the same notion in the same angelic intellect; if, therefore, in those acts the same spiritual specific notion is found contractible to diverse individuals, not from diverse subjects, but from diverse individual differences in order to the same subject, why could not the same substantial and spiritual specific notion be similarly contracted through individual differences proportioned to it? Certainly no sufficient reason can be given. And similar arguments can be taken from other simple entities which can be distinguished in number by themselves, such as two matters or two quantities, as we shall see more fully in the following section.

30. Finally, the divine power is limited without cause so that it could not create several angels similar in essence and species, or, if it had willed to annihilate the evil angels, could not have created others similar, which is certainly incredible in itself; and therefore almost all the other theologians, In II, dist. 3, teach that this can be done by God: Scotus, q. 7; Durandus, q. 3; Gabriel, q. 1, and others; and Marsilius, In II, q. 3, a. 3; Alexander of Hales, II p., q. 20, last member, a. 2, and Metaphysics VII, text 41; and among the Thomists Ferrariensis, Contra Gentiles II, 93, says that such numerical distinction of spiritual substances is not repugnant by absolute power, although he denies that it is according to the natural order of things; and St. Thomas favours it, Opusc. 16, last chapter, where he teaches at length that immaterial substance is one in number, singular and individual, because of itself it is not born to be participated by many; but he adds that it is of a rude intellect to gather thence that it cannot be multiplied by God. But whatever may be the case with this manner of speaking, whether this is to be called possible by absolute power or by natural or ordinary power, which is perhaps a question about a name, nevertheless, by whatever reason it is possible, it is sufficiently concluded that immaterial substance is not individual by virtue of its essential and specific notion; for, if it had this, it would imply a contradiction that such a substance be multiplied individually, just as it implies that the same individual be multiplied numerically. Whence it is also evident in passing that those are ignorant of the proper meaning of the word who say that in angelic natures there is a truly specific objective concept and logically (as they say) universal, and yet that that nature is of itself so incommunicable that it implies a contradiction for it to be in several individuals distinct only in number; for this is an open repugnance; for, if that nature can in no way be in many individuals, it is because of itself and from its proper essential concept it is so incommunicable; therefore, if it is such, it is repugnant to abstract it from this individual and render it communicable or indifferent, because this very abstraction is against its nature and essence, as is openly evident in the divine nature. It is therefore more truly and more consistently said that, just as in immaterial substances there are true and proper species, so also there is an individual which adds something according to reason over the species, and consequently that there can also be several similar individuals. But whether in fact there are, and what in this is more consonant with the Scriptures and the Fathers, pertains to theological disputations.

Satisfaction is made to the foundations of the other opinions

31. To the foundation of the first opinion the answer is that all those things which are enumerated in the first argument only indicate that the specific nature expresses an objective concept prescinded according to reason from individuals, and conversely that the individual adds something distinct by reason over the specific nature. For human science is of things universally conceived, of which definitions and demonstrations are immediately made; and for this it is enough that they can be abstracted according to reason, although in the thing itself they are not separated. Which is evident from what was said of the concept of being, of which there is science and demonstrations are made, although it is evident that in reality it is not prescinded from the proper notions of beings, but only abstracted according to reason. Whence this distinction too is enough for those causal expressions: because man is risible, Peter is risible; because in them no real and physical cause is given which intervenes between Peter and risible, but the adequate reason and origin of that property is explained.

32. To the second the answer is that in arguments of this kind (which I noted above in treating of the concept of being) an equivocation is easily committed by arguing from our mode of conceiving and from the use of the words by which we signify things as conceived by us to the things themselves as they are in themselves, gathering a distinction of things from a distinction according to reason, which is a fallacious argument. The answer, then, is that man as such, signified and conceived, does not express nor include in his essential notion any individual difference, as the argument rightly proves. And it is evident, because according to reason he is prescinded from all of them and can be contracted and determined according to reason through several differences of this kind. Whence it is rightly concluded that something must be added, which is outside the essence of man so conceived, in order that he become singular; I deny, however, that there follows thence a distinction in the thing between the common nature of man and his individual difference, because the nature of man is not found in the thing so common and abstract as it is conceived through the intellect. But when it is said that what is of the essence and what is outside the essence are distinguished from the nature of the thing, and not only by reason, the answer is that something can be understood to be outside the essence in two ways. In one way according to the thing, or considering things as they are in reality; in another way according to reason prescinding one from another, although in the thing it is not prescinded. In the former way it is true (especially in finite things) that whatever in reality is outside the essence must be distinguished from the nature of the thing from it, because it cannot be said to be outside the essence for any other reason; I deny, however, that in this way the individual difference, for example of Peter or Paul, is outside the essence of man as existing in the thing itself; for man does not exist in the thing except in Peter, Paul, etc., and in each his proper difference is of the essence of man as existing in him. You will say that it follows thence that man in Peter and Paul differs essentially, or that Peter and Paul do not have the same essence. The answer is that they do not have the same really, yet have the same by reason, which in the thing is nothing other than to have a similar one; and because to differ essentially, under these words, does not signify only the real distinction of essences, but also denies essential likeness and agreement, and so unity of essence according to reason, therefore it is simply not conceded that things which differ only in number differ essentially. Nevertheless, if those words were taken only in the former sense, it would be true that Peter and Paul differ essentially; according to which signification we deny that in God the Father, Son and Holy Spirit differ essentially, because they have neither essential difference nor distinction of essences. But in the latter way, namely according to the prescission of reason, everything without which such a conceived notion can be preserved is said to be outside the essence of the objective concept; and in this way it is not necessary that what is said to be outside the essence be distinct from the nature of the thing from the other; but it suffices that it be distinguished by reason, because that very word outside does not signify absolutely to be outside the thing, but to be outside the concept, or outside the thing as conceived.

33. Whence to the confirmation the answer is to be given by almost the same distinction; for in reality man is not constituted as man precisely, nor separated in himself, but is constituted as Peter, Paul, Francis; whence in each man is constituted by the same thing as Peter; nor is there in the thing something truly one constitutive of man which is in reality common, but there are several constitutives of individual men, in which the common notion is said to be fundamentally on account of the agreement and likeness which they have among themselves, as we shall say more fully in the following disputation. But according to reason, just as common man is abstracted, so he is understood to have an adequate and common constitutive; yet thence it can only be concluded that that is distinct by reason from the singular differences which specially constitute individuals. To the third the answer is that from what was said of the concept of being it is evident that those arguments do not prove a distinction from the nature of the thing; and we shall show the same of universal and inferior natures in the following disputation.

34. To the first argument of the second opinion the answer is that it rightly proves that a thing does not become singular through the addition of a reality or mode distinct from the nature of the thing from the nature which is said to become singular, because every such distinction supposes entity and consequently singularity in each extreme. But that argument does not prove that a thing cannot become singular through the addition of something distinct by reason, because this distinction does not suppose actual entity, and consequently neither singularity, in each extreme, because, since this distinction is through concepts, it can easily be understood between a thing universally conceived and its mode.

35. And according to this doctrine some things are easily solved which Cajetan, De ente et essentia, c. 2, q. 4, objects against the doctrine of Scotus, in so far as they can be applied against the first and third conclusions posited by us, such as that one: a singular act supposes a singular potency, Physics II, c. 3, text 36; but what the individual is said to add over the species is a singular act of the nature; therefore it supposes a singular nature, because it regards it as a potency. For the answer is that the major is true of real act and potency, distinct from the nature of the thing, of which Aristotle speaks in the place cited; not of act and potency distinct by reason, for the cause explained. Just as a specific act too does not suppose a specific potency, but a generic one. Another argument of his is: what belongs to one individual and is repugnant to another supposes their distinction; but the individual difference is of this kind; therefore it does not make the distinction, but supposes it. But this argument by virtue of its form is weaker. For the major can easily be denied, as is evident in a similar form: what belongs to one species and is repugnant to another supposes their distinction; for there would have to be added, or makes it; the same, therefore, would have to be added in the present case. Nevertheless, if the argument were made not of the individuals themselves, but of the nature which is contracted through this individual difference, it can have force against a distinction from the nature of the thing between that difference and the nature, but not against our opinion. For in distinct individuals there are also really distinct natures; whence, if the individuating differences are distinct from them from the nature of the thing, it is necessary that the difference which belongs to one and is repugnant to the other supposes their distinction and does not make it; because it supposes, as has been said, a singular potency proportioned to itself, and consequently distinct from another which is not proportioned to it; and so it will no longer be an individual difference, as we also argued above. But the distinction from the nature of the thing being taken away, the argument does not proceed with respect to the nature to be contracted, because in this way there is not one and another nature, so that the difference could belong to one and be repugnant to the other, but it is one according to reason. But if the discussion is of the nature not as contractible, but as contracted, then it is already the individual thing itself, which is constituted through the difference itself and distinguished from another.

36. To the second the answer is that it proceeds only of the ultimate formal notion of one, or of individual unity, which consists in negation, of which we confess that it adds nothing over the individual entity besides the negation; but we are treating of the foundation of this negation, and of that which the singular entity adds over the common nature, by reason of which it is capable of such a negation.

37. To the third some say that what the individual adds over the species is accidental. But that this is false is convinced both by the arguments made there, and by others which we shall make in the following section, and also from what has been said; for, if this addition is distinct only by reason from the substance or essence of the thing, and is per se conjoined to it as per se determining the common nature to the particular, how can it be accidental? Others, then, simply call this essential to the individual, not to the species, which in truth is so, if we consider the thing itself, for what altogether intrinsically constitutes and composes this individual is its proper difference together with the common nature; nor can this individual not only be, but not even be conceived, without such a difference. Nevertheless, according to reason, and according to the manner of speaking of the dialecticians and metaphysicians accommodated to our mode of conceiving, this individual difference is not called essential, but intrinsic, entitative and as it were material, in order that it may be distinguished from the specific difference, which is most formal; for it is taken from that grade in which individuals formally agree or are assimilated. And so this seems to have to be declared thus: that individuals of the same species, with real distinction, have an integral and perfect likeness in nature, in which they differ from individuals differing in species under the same genus, which do not have among themselves so great and so perfect a likeness. Hence, then, it comes about that our mind conceives that in which those individuals agree among themselves as one something and as that which is formal in them and which per se contributes to science; for distinction in entity alone is judged to be as it were per accidens, and therefore it is called material. And for the same cause the scientific definition is not given except of the common and specific concept, and in this sense the lowest species is said to be the whole essence of the individuals, namely formally and precisely taken and conceived, and as its knowledge serves human science, which does not descend to particulars according to their proper and individual notions, both because it can neither perceive them as they are in themselves, nor does it treat of the proper accidents of individuals, because either they belong to them contingently and per accidens, or, if perhaps there are some altogether proper, they lie as hidden as the individual differences themselves. Finally, because it would be very laborious and almost infinite to descend to individual particulars. Nevertheless there is no doubt that individuals, even if they differ only in number, have distinct essences in the thing, which, if they are conceived and explained as they are in themselves, will have to be declared by diverse concepts and definitions; and they will also have distinct properties, at least according to the thing or according to some proper mode, under which notion they fall under angelic or divine science.

38. To the foundations of the third opinion the answer is as follows. To Aristotle in Metaphysics VII it can first be answered, with Alexander of Hales there, that when Aristotle says in things separated from matter the quod quid est is not distinguished from that whose it is, he does not take matter with all propriety for prime matter or for the proper subject of some form, but for any supposit whatever which in reality is in some way distinct from its nature; in which way no created substance can be said to abstract from matter, because in all the nature is in a supposit in some way distinct from it. This doctrine is true, but I do not think that Aristotle spoke in that place in that sense. Alexander of Aphrodisias expounds it otherwise, who thinks, and in truth very probably, that Aristotle in each place cited above spoke of the same substances and compares in the same way the quod quid est with that whose it is. Which can be confirmed from the words of the same Philosopher; for he says in that text 41: It has been said moreover that the quiddity and each thing are the same in some things, as in first substances; for so Alexander himself reads. And although in the text commonly in that place that particle, it has been said, is not repeated, nevertheless that which had preceded a little before also comprehends this clause, as is sufficiently evident from the context. Hence, then, by first substance Alexander does not understand immaterial substances, as St. Thomas does, because Aristotle in the latter place refers himself to what he had said in the former; but there he had said nothing of immaterial substance in special, nor in the other does he bring forward a special reason on account of which he constitutes a difference in this between material and immaterial substances; nor is there any indication on account of which we should say that he uses that term, with that whose it is, equivocally, so that in the former place it is taken for the thing defined, but here for the supposit, so that the comparison made in each place would be diverse. And finally Aristotle never used the name of first substance to signify specially immaterial substances; for, although in Book IV, c. 3, text 7, he seems to use that word in that signification, nevertheless the Commentator there understands God by first substance, and whatever may be the case with that place, no argument is taken thence to the other in which we are now engaged; and so according to this exposition the opinion of Aristotle in each place is the same. By first substances, then, Alexander understands any substantial supposits whatever, from which the quod quid est, that is, the common nature, is not separated. But what Aristotle adds, I call first substance that which is not said by reason of one thing being in another, as in a subject or matter, is explained by Alexander of substance which is not signified as one thing in another, but as one thing consisting per se, in which it differs from the accidental composite, as is white, for example, or snub, in which something is signified as existing in a subject as in matter; for of a composite of this kind, from such a subject as matter and an accident as existing in it, Aristotle adds that in it, since it is one per accidens, the quod quid est is distinguished from the subject in which it is. And so according to this exposition nothing can be gathered from the aforesaid text against our opinion. Besides this probable exposition, however, that place has another perhaps more probable; yet, because it touches the question of the distinction of nature from supposit in immaterial things, it will be handed down more conveniently below in the disputation on the distinction of nature and supposit in created things.

39. To the other testimony from De Anima III, if the common exposition is to be retained, nothing can be answered except that Aristotle was of that opinion, which Scotus finally concedes, In II, dist. 3, q. 7, ad 1, where he says that Aristotle thought that the angels are beings necessary per se, and therefore could not consistently think that there could be several angels in one species; for, if there could be, there would be in fact, because in things per se necessary and eternal to be and to be able are the same. And similarly, if there could be several, they could also be multiplied to infinity, and finally would actually be infinite. But the foundation of this discourse is uncertain, namely that Aristotle thought the angels to be beings necessary per se. And perhaps Aristotle, when he posits this difference between material and immaterial individuals, does not speak precisely and metaphysically of the individual as it expresses singular substance alone, but speaks physically of the individual as it is in the thing itself affected by its accidents; in which way he seems to speak in the said place of De Anima III; for he says that the material individual is such that sense is concerned with it, which is not true of the individual taken with rigorous and metaphysical prescission, but only in the latter and physical way. And so a difference between the material and spiritual individual can easily be found.

40. To the reason of the aforesaid opinion (whatever may be the case with that opinion that in material things signate matter is the principle of individuation, which we shall dispute immediately) the answer is that, although in immaterial things this principle of individuation is not given, some proportional one must nevertheless be given, because those substances too are individual not by virtue of their specific notion, but of their singular one. Whence, when it is said that spiritual substance is individual by itself, if by itself is understood as by virtue of its specific notion, the question is begged and something false is assumed, as has been proved; but if by itself is understood as through its own entity, this is indeed true, but nothing prevents that in that very entity the specific notion and the individual difference are distinguished by reason, and that the same entity according to diverse respects can be the principle and foundation of each. For as regards this the reason is almost the same concerning material substances; for, whether signate matter is said to be the principle of their individuation or anything else whatever, nothing can be which is not the very essential entity of the thing, either whole or partial; whence in the same it is necessary to distinguish both the specific notion, on account of which it is said to be essence or part of essence, and another notion, distinct not in reality but by reason, on account of which it is said to be the principle of individuation.