Cursus Philosophicus Thomisticus, Secunda Pars Philosophiae Naturalis

Generally speaking, every increase or decrease is called quantity, wherever it occurs, because what is most perceptible and evident to us in the increases of things is quantity. This account of quantity can be found in qualities or forms in three ways. First, by extension in a subject; this belongs only to qualities inhering in a subject that has quantitative parts, as when whiteness is diffused through a subject and grows in it because it is in more parts of that subject. In this way a quality is called great or quantitatively large per accidens, by the quantity of its subject. Second, quantity or magnitude is attributed to a quality on the side of the object about which it is concerned. This applies to habits of intellect or will, which concern certain objects and comprehend sometimes more and sometimes fewer of them; in this respect they are said to extend or increase in relation to their objects. This is called virtual extension, or quantity of power, because a power is called great in relation to the object, or the weight, it can bear. Third, a quality’s quantity or magnitude is said according to its participation in a greater perfection through more and less. This pertains to intensification and remission, on which see St. Thomas, De virtutibus, q. 1, a. 11, ad 10.¹

Concerning this intensification, then, we assume two things in the present article and discuss one of them, the more difficult one.

First, we assume that such an increase by intensification and a decrease by remission exist; this pertains to the question whether they exist. This is evident from experience itself. We see qualities increase or decrease in more and less, and this cannot be reduced to the other two extensions or magnitudes just described. For we see heat, whiteness, or light sometimes become more perfect and greater, not because it occupies more parts of the subject—it occupies the same parts—nor because the subject is denser or rarer. In the same air, for instance, sunlight is more perfect than moonlight, though the air has the same rarity. This increase therefore does not pertain to quantity by formal extension. Nor does it pertain to virtual extension, since light, heat, and similar qualities do not have different objects about which they are concerned, but rather subjects that they inform. It remains, then, that there is a quantity and increase by intensification according to more and less.

Second, we assume a definition of intensification; this pertains to the question what it is. Intensification may be defined as “motion from a less perfect being or state of the same quality to a more perfect one, while the same sensible subject remains”; remission, conversely, is “motion from a more perfect to a less perfect state.” So teaches Master Báñez² in q. 2, On Alteration. The phrase “from a less perfect being or state” is used so that the definition abstracts from every opinion about whether intensification occurs through different degrees, different modes, or different participations in being; we shall discuss these later. It is called “motion,” the genus of alteration and consequently of intensification. But since not every intensification occurs through alteration properly so called, as happens with spiritual qualities, we use the general term “motion.” This also excludes the acquisition of a new state in some quality or form, not through motion but through an elevation or a different mode of operation, as when charity in this life changes its state in heaven—not through greater intensification and motion, but through a new apprehension of an object clearly seen. Finally, the phrase “of the same quality to a more perfect state or being” signifies how intensification differs from simple alteration: simple alteration first and per se produces the quality itself, not merely a more perfect state or being of that quality.

We inquire, then, which forms are capable of this increase and magnitude according to more and less, namely, intensification and remission. This difficulty must be resolved through several conclusions.

I say, first: Substance is incapable of an increase by intensification, and so too are quantity and relation.

This is the Philosopher’s express teaching, and all his interpreters commonly follow it. In the chapter “On Substance,”³ one of its properties is said to be that it does not admit more and less. He teaches the same about quantity in the chapter “On Quantity,”⁴ and about relation as well,⁵ which admits more and less only by reason of its foundation. For example, similarity is more intense when the agreement of its extremes is greater, even if the forms themselves or the things are less intense in themselves. Thus the intensification of a relation follows the intensification of its proximate foundation, not its remote one.

The foundation of this conclusion can be taken generally: no motion is given primarily and per se in these three categories, strictly speaking—that is, motion according to a positive range—whereas intensification is a kind of motion. If some motion is given, it is according to extension, as in the increase of quantity. Substance, as is clear, comes to be through a change and not through motion, since it does not come to be from the same sensible subject but from prime matter. Likewise, when quantity is first produced, it follows generation itself without another motion. When it is later extended, it admits the motion of growth, but not alteration and intensification. Thus one part of quantity added to another does not make a more perfect degree, but an extension of a perfection of the same kind: it makes something greater, not better. This is especially clear because the species of quantity vary essentially according to different terminations, as is evident in numbers and figures, in a two-cubit and a three-cubit length, and so on. It belongs to their account to be indivisible or terminated; therefore they do not admit a range within the same species. Finally, there is no per se motion to relation, as is said in Physics V and as we proved there, q. 19,⁶ since relation merely results once its foundation is posited; no motion is directed to relation. Thus relation does not have intensification primarily and per se; if it has it at all, it follows from its foundation.

Second, the foundation is taken specifically from St. Thomas in Summa theologiae I–II, q. 52, a. 1: the form from which the species of the thing it actualizes is taken cannot fail to consist in something indivisible and consequently cannot admit more or less. For if what constitutes the species had a range, then either that whole range would be required to constitute the species, or the species could be constituted without the whole range, even if some part were lacking. In the first case, divisibility is not preserved in such a form, since the species is constituted not by its range as such, but by its totality and completion, which implies indivisibility; for what is ultimate is always indivisible. In the second case, the species is preserved without some part of that range, and what can be lacking without the species being lost does not belong to the constitution of the species or count as a quidditative predicate, since the quiddity is preserved without it.

From this it follows that a substantial form does not admit more and less, because it is intrinsically ordered per se to constituting the substantial species of the thing whose form it is. Although quality and other accidents also have their own species and essence, those forms are not ordered to constituting the species of their subject, which they inform; they presuppose that species as constituted and therefore do not first and per se constitute the species of what they inhere in. A substantial form, however, first and per se constitutes the species of what it is in; for this reason substantial form is incompatible with intensification, or the reception of more and less. An accidental form does not have this incompatibility on that account, although other conditions are required for intensification to belong to it in fact. For now it suffices that a substantial form gives the thing in which it is an essential and per se species, whereas an accidental form does not but presupposes the species as constituted. St. Thomas was therefore precise in the passage cited: he did not say that substantial form does not admit more and less simply because it has a species or gives it in some way, but because what participates in such a form has its species according to that form. We must therefore consider the function a form exercises in its participant or subject, in which it is received. If a subject is related to a form in such a way that through it the subject has its species and constitutive principle, that form does not admit more and less in that participant. As for other forms, which come to a subject without giving the participant its species, but rather come to something whose species is already constituted, there is no incompatibility on this account with their having some range in that subject. This is so even though they have a species of their own, provided that it does not constitute the subject in which they are participated; their participation in a subject can therefore admit a range of more and less.

But if you say: Every species consists in something indivisible, for species are like numbers, which change whenever anything is added or subtracted: We reply that it is one thing for a species, as regards its constitution, to consist in something indivisible, and another for the subject participating in such a form to be constituted by that very indivisibility, or for indivisibility itself to be a predicate among the constitutive principles of that species. This is not found in every species. Therefore not all species are incompatible with the divisibility and range they have in the subject’s participation, even though every species is said to consist in something indivisible on account of the integrity it requires of all essential predicates for its constitution. Not every species, however, excludes divisibility on the side of the subject’s participation, from which the range of intensification is taken, as we shall say shortly.

I say, second: Intensification is found only in quality, though not in every species of quality.

If we speak of physical intensification, which is a species of alteration, there is no doubt that just as alteration is found only in the category of quality, so too is intensification, its species. But lest someone say that intensification can be found in spiritual things and not only in alteration, the conclusion must also be proved more generally. First, there can be no doubt that intensification is found in this category, at least in some of its species, since this rests on manifest experience: we see heat sometimes intensified and sometimes diminished. The same holds for the other primary qualities and for intermediate qualities, such as color, rarity, density, and the like.

Considering the species of this category one by one, and asking which can undergo intensification not only in the altering sense (for this is reduced to the third species alone, just as alteration itself is), but also in the broader sense, we see first that habit and disposition can be intensified. Habits of the virtues are sometimes more vigorous and sometimes more remiss; likewise, knowledge is sometimes deeper and more effective, sometimes duller. This is not only a matter of extending to different conclusions: with respect to the same truth, there can be greater clarity and a deeper resolution to its principles, which pertains to greater intensification. Thus someone is called more knowledgeable or more virtuous. This also extends to supernatural habits, as is said of charity in Philippians 1:⁷ “I pray that your charity may abound more and more”; and in the last chapter of Revelation:⁸ “Let the one who is just be justified still.” Finally, the Council of Trent, Session 6, chapter 10, defines the increase in justice of those who have been sanctified.

As regards the second species, some think it does not admit more and less—for example, intellect, will, and the visual power—because these are proper attributes and follow immediately from the essence of a thing by emanation, not by motion, and they do not belong to a subject according to a range of contrariety. Master Báñez takes the opposite view in On Generation, Book I, chapter 4, q. 3, final conclusion; he gives the example of the visual power, which evidently admits more and less: sometimes sight is sharper, sometimes duller. An eagle certainly sees more intensely than a human being; among human beings, some see better and more keenly than others; and after the resurrection the eyes of the same human being will see incomparably more keenly than they do now. It is no objection that these are proper attributes of the soul, since heat and dryness and the other primary qualities are also properties of the elements and yet admit more and less. Cajetan takes a middle position at the end of Summa theologiae I–II, q. 52, a. 1,⁹ and says that natural powers which follow substances immutably are not intensified, just as substances themselves are not; those that do not follow immutably but depend on some alteration, such as hardness, softness, and similar qualities, can admit more and less. Since powers attached to bodily organs depend on the altering qualities that temper those organs, it seems that they can admit more and less: the visual power, for instance, can be sharper, as can hearing, and so on. This view seems quite reasonable. There is no reason why powers of this kind, which depend on primary qualities or alteration, should not admit more and less, especially since experience supports this: we perceive intensification and remission in them, as is evident in the visual power, in softness and hardness, and in other cases. Nor is it an objection that they come to be instantaneously, since some things that come to be instantaneously can also be intensified, such as light and spiritual acts of intellect and will. Some powers are not intensified, as Cajetan says,¹⁰ because they follow a nature immutably—that is, independently of altering qualities. In particular, powers belonging to something according to the ultimate constitutive degree of its nature, such as intellect and will according to the rational degree, do not admit more and less because that degree itself signifies a kind of ultimacy. Thus the rule is not whether a quality is a proper attribute, but whether something indivisible belongs to the account of a form, as we suggested above. Accordingly, some powers do not receive a range of more and less because they follow substance immediately and independently of alteration; other powers, which do not follow it so immediately and are not independent of alteration and primary qualities, admit more and less by reason of those qualities.

As regards the third species of quality, there is no doubt that intensification can be found in it, and that it can be physically altering, since, as we proved in the preceding question, physical alteration properly occurs in the third species of quality; consequently intensification, which is its species, can occur there as well. This is also evident to the senses from heat, cold, and the other sensible qualities belonging to this species.

Finally, in the fourth species of quality there is no motion of intensification, because the account of figure, which belongs to that species, includes the termination of quantity from which figure results; any variation in termination changes the species. Termination occurs according to something indivisible and therefore is incompatible with a range of intensification.

I say, finally: Besides intensification, which is motion according to more and less, and besides extension through the quantitative parts of a body, there is also, in some qualities, an increase by extension—not according to the parts of the subject in which the quality inheres, but according to the objects it reaches, since those objects are inadequate. A habit is said to increase more extensively insofar as it reaches different objects.

This is taken from St. Thomas, Summa theologiae I–II, q. 52, a. 1, ad 2, and II–II, q. 24, a. 5, where he teaches that some habits increase by addition with respect to their objects. For example, knowledge, which is learned gradually, newly increases with respect to different conclusions it did not previously reach. This increase is not intensification, since it does not concern the same truth but different ones. Knowledge is intensified when it comprehends the same truth more clearly and deeply.

Concerning this extensive increase, note three propositions of St. Thomas. The first is that such an increase does not occur in every form or quality, but in those specified by something extrinsic or expressing an order to another. So he teaches in Summa theologiae I–II, q. 52, a. 1, at the end of the body of the article.

The second is that this increase is not found in every habit expressing an order to a specifying object. Charity, for example, expresses an order to an object, yet it does not admit addition by extensive increase, as St. Thomas teaches in the cited Summa theologiae II–II, q. 24, since the least charity fulfills the whole law and resists every temptation; every degree of charity therefore reaches all its objects, namely God and neighbor. It does not become greater by extending to objects. Knowledge, however, needs this extension because it proceeds through distinct means to prove distinct conclusions. Although all those means are coordinated with one another and belong to the same habit under the same light, they require different explanations of the object, distinct species or their arrangement, and distinct means of proof. We discussed this more fully in Logic q. 27, a. 2.¹¹

But if you say: Moral virtues, even when infused, can also face a new difficulty concerning different partial objects, as we said in the cited passage of Logic;¹² indeed, we drew from this an argument to prove that knowledge is a simple habit, although it overcomes distinct inadequate difficulties. Therefore it is false and inconsistent to say here that moral virtues do not admit addition, but knowledge alone does.

We reply that, as we said in the cited passage of Logic, in the answer to the confirmation of the first argument,¹³ infused virtues such as charity and faith can face different difficulties concerning different matters, not on the side of the virtue itself but on the side of the agent; this is an accidental difficulty, and yet a single simple quality suffices to overcome them. So too one quality will suffice in the sciences to overcome distinct difficulties concerning distinct conclusions, although it requires different inadequate motives for them, since those motives are united under the same formal account and light. The motives are coordinated with one another, since one is derived from another. Thus a strong argument from similarity proves that one quality suffices to reach different conclusions, even though each has its own proof and distinct motive, and a distinct difficulty on the side of the means themselves, not only on the side of the agent. There is still room for unity of habit, because its principal account, from which its unity is taken, is preserved—namely, the same formal scientific account under which all those motives and proofs are coordinated and contained. Therefore, if one quality can reach distinct matters and overcome distinct difficulties on the side of the agent, provided that the same formal account is preserved, as is evident in the virtues, then with the unity of the formal account preserved, it is likewise possible for the same quality to reach different conclusions and overcome distinct difficulties that require distinct means, all ordered under the same single formal account and light.

The third proposition is that St. Thomas says this extensive increase occurs by addition, by which a habit is increased in itself, whereas intensification occurs through rooting in the subject and not by addition. This is not because a new quality is added in extensive increase (St. Thomas denies this in Summa theologiae I–II, q. 54, a. 4), but because a new objective increase is added, and because an order to an object is said to belong to a habit in itself, whereas participation and the rooting of intensification occur through an order to the subject, according to St. Thomas’s view. Thus, to distinguish one increase from the other, the former is said to occur by addition, while the latter is not: in the former a new object and a new expression of the habit in relation to it are added; in the latter no new subject is added, but intensification takes place in the same subject. Nor is a new entity of quality added, so there is addition in no respect.

The arguments are answered.

First it is argued: Intensification cannot increase a quality according to more and less unless the species and essence of the quality itself vary. Therefore the account given of intensification is null. The antecedent is proved as follows: that according to which a quality becomes more or less is the proper account and species of the quality itself; but species are like numbers, changing whenever anything is added or subtracted.

If one says that intensification occurs according to more and less not in the essential and specific account itself, which consists in something indivisible, but in something extrinsic—for example, through the addition of a degree or new entity, or through greater participation or rooting in the subject—there is an objection. First, intensification cannot occur by adding a new quality of the same species, as we shall say in the next article. Nor can different participation and rooting in the subject occur according to something accidental, but only according to the very essence of the quality. St. Thomas says that the opposite view is ignorance of the proper meaning of the words, in Summa theologiae II–II, q. 24, a. 4, ad 3, and De virtutibus, q. 1, a. 11.¹⁴ Therefore variation through intensification occurs in the very essence. Further, if intensification does not occur through a variation in the essential account, or species, of the quality itself, but in something extrinsic or pertaining to individuation, it follows that substantial forms could be intensified, since their indivisible species could be preserved while they increased according to more and less in something extrinsic and individual—for example, by being united to a subject in a more perfect way or by being the root of a more perfect mode of operation. Why, then, would there not be an increase by intensification in substantial forms?

The same argument can be made about quantity. Through different modes of terminating a subject, it can be participated in that subject more or less perfectly in an extrinsic way that does not pertain to its intrinsic species. Why, then, would quantity not admit more and less?

We reply by denying the antecedent. To the proof we say that intensification does not vary the species, but the mode in which the species actualizes the subject and reduces it more perfectly from potency to act, as will be said in the next article. For an addition or subtraction to vary the species of a form, it must add or subtract a quidditative predicate, or an intrinsic mode of such predicates essentially required. It is not enough to add or remove merely some mode of different participation in the subject or the addition of a new quasi-integral entity, as we see that more or fewer integral parts can be added to or subtracted from a material substance without varying its species.

To the first rejoinder we say that intensification does not occur through the addition of a new entity, but through greater rooting in the subject, as we shall say in the next article. St. Thomas says that those who claim a form is increased by rooting in the subject and not according to its essence are ignorant of the proper meaning of the words because they understood rooting not to pertain to the entity of the accident, whereas the entity of an accident itself demands inherence and participation in a subject; thus greater rooting undoubtedly involves the entity itself. St. Thomas therefore says in the cited place in Summa theologiae II–II that increasing something according to its essence is nothing other than its being more in the subject, which is its being more deeply rooted. We shall discuss this further in article 3.

To the second rejoinder we say that a substantial form is prevented from being intensified because it has no range or contrariety by which it could be capable of motion and consequently intensification, as was said above.¹⁵ Although an indivisible species of form could remain while a divisible increase according to more and less took place, this does not occur in a substantial form, because it not only has a species in itself, but constitutes in its species the composite it informs. Thus it establishes no range either on the side of its species or on the side of its participation and the participating subject. If it is varied in any way, its whole species is varied, both in itself and in the subject’s participation. The case is different with an accident: through its participation the subject itself is not constituted in its essential species but is presupposed as already constituted. On this account, an accidental form is not prevented from being intensified or remitted. It does not follow, however, that all accidental forms can be intensified or remitted if they lack other conditions, such as contrariety or a range, so that their indivisibility in constitution is not intrinsic and does not belong to their account. We noted this above concerning the constitution of species of quantity,¹⁶ and concerning other species of quality that lack a range and include indivisibility.¹⁷

But if you say: Aristotle in Metaphysics VIII, text 10,¹⁸ and St. Thomas there, lecture 3,¹⁹ say that matter perhaps admits more and less. St. Thomas replies in Summa theologiae I–II, q. 52, a. 1, that this is understood of matter according to its material dispositions, not according to its substance, according to which it composes with form an indivisible species of nature.

Second, you will object: A quality has contrariety in itself, prior to its relation to a subject—for example, it is contrary to cold. It does not derive its contrariety from its subject. But where there is contrariety, there is the greatest distance; therefore there is also a range according to more and less, and consequently intensification and remission. Indeed, contrariety between forms exists only according to degrees, for qualities are not contrary at remiss degrees but at intense ones, where alone they are incompatible. Therefore they are said to have more and less not in relation to a subject, but in themselves.

Again, if God were to separate the whiteness of snow and the whiteness of a human being, the former would be more perfect than the latter, not through rooting in a subject, since they would be outside a subject; therefore, this would be according to themselves, and so it would not be incompatible with substance to have intensification.

Finally, the whiteness in the concrete and the whiteness in the abstract are the same. Therefore, if whiteness in the abstract is not intensified, neither is it in the concrete; or conversely, if it is intensified in the concrete, it is also intensified in the abstract. If an accident in the concrete, such as “white,” is taken not for the form existing in a subject but for the composite of body and whiteness, then it is not intensified, because one of its constituents, the body, is not intensified.

We reply that although some qualities ground contrariety in themselves, as between form and form, and not only according to a subject’s participation (although contrariety cannot be exercised except in a subject, since contraries drive one another out of the same subject), the range and distance according to more and less in the intensification of forms is not taken from some contrariety between form and form, but from the range of the form’s participation and rooting in the same subject. When it is said that where there is the greatest distance there is also a range of more and less, we reply that this is more and less among different forms that are not the extremes but intermediates between contrary extremes. More and less in the same form, however, do not ground contrariety and distance except with respect to the subject in which the form is rooted and participated. Thus contrariety between form and form, whether according to the greatest distance or according to intermediate forms, belongs to forms in themselves; distance according to more and less in the same form belongs to it only according to its different participation in a subject. Contrariety between form and form therefore comes from the very nature of such forms, although a perfect state is required for contrariety to be exercised, and this occurs only in perfect degrees, since imperfect degrees are reckoned within the same subject, as we shall discuss below, q. 10.²⁰

As for the whiteness of a human being and of snow when separated, we reply that one will be more intense than the other, not because it is actually more deeply rooted in a subject, since they lack one, but because of the aptitudinal rooting they retain and the order they express toward a subject. When St. Thomas says that separated whiteness has every perfection possible and cannot be intensified, he is speaking of whiteness if it were subsistent and referred to a subject neither actually nor aptitudinally.

Finally, concerning what is said about whiteness in the abstract and in the concrete, we say that it is the same form, but not in the same state or with the same relation: in the concrete it regards a subject, whereas in the abstract it leaves the subject aside. Hence St. Thomas says in Summa theologiae I–II, q. 53, a. 2, ad 3, that intensification and remission are attributed to accidents in the concrete; thus we do not say “more whiteness,” but “whiter.” “White,” taken for the composite, is not intensified by reason of the whole, but by reason of a part—namely, by reason of the form insofar as it can be communicated to a subject.

Almost everyone agrees that an increase in a quality either requires or entails some greater rooting in the subject, insofar as an intensified quality is firmer and more tenacious in the subject; this is what rooting means.

The difficulty, however, is whether this firmness, which is also an increase of the quality, requires the addition of a new entity or form in the way that increase in quantity occurs by adding a new quantity; or whether this greater rooting occurs without the addition of a new entity, through the addition of a new mode. There is also a difficulty about the mode itself: is it a new mode that adds a new informative power, or formal character of informing, to the form itself, or is there added only a new mode that is a new expression or application of the same form, without the addition of a new formal character? We use the word “degree” in common to both views, since “degree” signifies not only a diverse entity superadded but also a diverse mode. Thus we designate the perfection of intensification generally by the name “degree,” whether it occurs by adding an entity and form or by adding a mode, since a different mode can also confer a degree something. Hence Cajetan, who banished addition from intensification in ST I-II, q. 52, a. 2,¹ nevertheless did not reject the expression “degrees,” as is clear in the same place, § “For clarification.”

The principal opinions on this question therefore reduce to two. The first is that intensification occurs by adding one quality to another. Since this addition does not corrupt the preceding quality but is joined to it and composes with it, it functions as a partial quality; thus this opinion conceives the intensification of a quality on the model of increase in quantity.

The second opinion teaches that intensification occurs without the addition of a new quality or form, but through a greater communication of the same form in the subject, which introduces a new termination or mode in the quality.

Scotus follows the first opinion in Sentences I, dist. 17, q. 5,² and among more recent authors Fonseca,³ Suárez,⁴ Vazquez,⁵ Rubius,⁶ Granado,⁷ and others cited by the Carmelites here, disp. 4, q. 8, § 1. St. Thomas follows the second in Sentences I, dist. 17, q. 2, a. 2,⁸ De virtutibus, q. 1, a. 11,⁹ ST I-II, q. 52, a. 2, and II-II, q. 24, a. 5; all Thomists commonly follow him.

There are, however, several further opinions divided within the explanation of each view. With regard to the first, some think that the partial entities or degrees constituting an intensified form are of the same nature and equal, and that the second or third degree has no more than the first; it is called second because it presupposes the first, to which it is added, and likewise for the rest. Others think that the degrees are of different natures and that the second degree is not of the same perfection and equality as the first. So holds Father Suárez, disp. 46, sect. 1, from no. 29. To these are added indivisibles that unite the degrees as parts; within the degrees as well there is a range of finite aliquot parts and infinitely many proportional parts. In a word, everything is considered on the model of an increase in quantity. There are, however, some who admit a subordination among these degrees, such that the second presupposes the first and the third the second, by a certain natural subordination and dependence, as on a material disposition; in this way they have individual inequality. See Murzia, disp. 2, De alteratione, q. 5. I omit the opinion older than Scotus mentioned by St. Thomas in the cited place, Sentences, a. 1,¹⁰ and later followed by Durandus, Sentences I, dist. 17, q. 7, no. 25, and others: that intensification produces a new total quality by destroying the old one. For this opinion does not posit that the same quality is intensified and diminished, but that a different quality is generated and corrupted.

In explaining St. Thomas’s opinion, there is also considerable labor over what is meant by rooting or greater communication. It is commonly understood to be some new mode, but the authors are much divided in explaining which mode. Some posit a new mode that gives the quality a new power to inform the subject, as it were, a formal character of communicating itself. Others posit only a mode of new termination or expression of the form in the subject, pertaining as it were to the union and application of the form itself. Hence some have said it is a new union or inherence of the quality; others, a new existence; others, a new reduction of the subject from potency to act, a mode distinct from inherence and union. Others think this mode consists in more of the contrary form being cast off, so that the form itself remains purer and less mixed. The same difficulty then recurs concerning the preceding opinions: do these new modes have some subordination among themselves and differ in nature and equality, or are they all equal, the second or third being so called only because it presupposes the prior one?

I say, first: Intensification does not occur through the addition of any new form or quality, whether one that corrupts the prior form and produces a new one, or one that produces a new form by presupposing the prior form, as a partial quality joined to it and making it greater.

This conclusion is explicit in St. Thomas’s places cited just now, where he treats and resolves this question directly. Indeed, all commonly admit the first part, that a form which corrupts its predecessor is not produced, because the preceding quality cannot be destroyed by what supervenes: it is not contrary to it, but of the same species. Nor is the quality destroyed through a defect in the subject or in the conserving cause, since, as we presuppose, these remain. Otherwise, as we said, this would not be an increase and perfection of the same quality, but the generation of a new one; likewise, one could not say that a quantity had increased if the preceding quantity were corrupted and another newly produced.

The second part, namely that in intensification no new part of a form or quality is made to be added to the preexisting form, is plainly St. Thomas’s opinion. In particular, see the cited place in ST I-II, q. 52, a. 2, ad 2,¹¹ where he says: “The cause that increases a habit always does something in the subject, but not a new form; rather, it makes the subject participate more perfectly in the preexisting form.” And in ad 3 he says: “What is less hot or white is not in potency to the form, since it already has the form in act; rather, it is in potency to a perfect mode of participation, and this follows from the agent’s action.” In ST II-II, q. 24, a. 5, he says: “For a form to be greater is for it to be more present in what receives it, not for another form to arrive; this would be the case if the form had some quantity of its own, rather than in relation to the subject.” Therefore, according to St. Thomas, greater rooting in the subject is not grounded in a new entity of the form, but in a new mode of participation in the form. Thomas does not merely deny that intensification occurs by addition, lest he seem to posit a distinction between forms, since intensification requires the same form to remain; he further explains that intensification does not occur by addition because no new form is acquired, but a new mode or participation in the form. He therefore holds absolutely that intensification occurs not through a new entity but through a mode.

Nor does this objection stand: some say that St. Thomas claimed to be unaware of the proper term when he said that a quality is intensified according to greater rooting in the subject, and not according to its essence. They infer from this that the holy Doctor thought intensification cannot occur without the addition of an entity. But St. Thomas’s meaning is perfectly clear. He rebukes those who wanted a quality to be intensified in the subject without being intrinsically perfected in itself, but only because the subject would relate differently to its participation in the form, while the form itself remained altogether unchanged. This is incompatible, and is to be unaware of the proper term. For a form cannot be communicated to the subject through an extrinsic denomination alone, but through an intrinsic change, since the form is perfected by the subject’s very communication with it; its essence is intrinsically ordered to informing the subject. Hence in the cited place from ST II-II, q. 24, a. 5, ad 3, after St. Thomas says that those who claim charity is not increased according to essence but according to rooting or fervor are unaware of the proper term, he adds: “For its being increased according to essence is nothing other than its being more present in the subject, which is to be more rooted in the subject.” Therefore, for St. Thomas, being increased according to essence does not mean being increased by addition; it means the same as being more rooted and more present in the subject. This is found in the form not without an intrinsic change of the entity itself, by way of a mode added to it.

Once we have established, then, that this is St. Thomas’s opinion, we must give the basis for this truth. To do so, St. Thomas presupposes as most certain that if an increase in intensity occurs by adding form to form, it is impossible to understand this without some distinction and numerical plurality of one form from another. For the same thing cannot be added to itself, and the separation of degrees when a quality is diminished and loses them clearly shows some distinction between what is lost and what remains.

Given this, two things in St. Thomas’s opinion make intensification by adding one quality to another impossible.

The first is that, according to St. Thomas himself, two accidents that differ only numerically and are of the same species cannot be received in the same indivisible part of a subject, as we will show below, q. 9,¹² If intensification occurred by adding a new quality of the same species, the same subject would necessarily receive accidents numerically distinct from one another, because each of those qualities, taken alone and apart from the other, suffices to make one individual accident. This is clear since, before the addition, the quality remained individuated in the subject without that new part being added. What is later superadded therefore also requires individuation by that subject, just as the prior quality did. Thus two accidents can already be individuated sufficiently by the same part of a subject, and their being joined into one is accidental. This grounds what St. Thomas, ST I-II, q. 52, a. 2,¹³ cites from the Philosopher in Physics IV, text 84,¹⁴ that intensification cannot occur by addition “because the hot becomes hotter without anything being added to the hot subject.” St. Thomas considers adding heat and adding something hot to be the same, because heat cannot be added without adding a distinct subject by which it is individuated; thus adding heat is equivalent to adding something hot. But this must be treated below, in q. 9,¹⁵ so it need not be examined here.

The second principle in St. Thomas’s teaching is that no form can have quantity and parts except by its order to a subject and accidentally, not per se. Otherwise it would be composed of several parts and thus would not be a pure form, but something constituted and composed, contrary to the nature of form, which must be something simple and a composing part, not a composite thing. If the arriving form does not compose with its predecessor or constitute one per se, the intensified quality will only be one accidentally, that is, several diminished qualities constituted in the same subject. An intensified quality would therefore not be as truly one quality as a diminished one, nor would the motion of intensification concern the same quality becoming more or less such, but rather different qualities. Furthermore, an operative quality, such as heat, when intensified could not operate by one operation but would have to perform several operations, because it would not proceed from one quality but from several. Thus, in producing an intense act of a quality, it would produce several acts, not one, because it would proceed from several diminished forms, each of which would have its own operation. All this is very absurd and unsuitable.

If several parts compose one quality, then, they are either integral parts or essential parts of it. They cannot be essential parts. First, because the essence of the quality is preserved without any one of them, as is clear in a diminished quality. Second, if essential parts compose one per se, one must be related as matter and the other as form, or as potency and act. But those parts, or degrees, function as forms, because they inform the subject. One cannot function as matter and the other as form, or as potency and act; otherwise a quality would inform another quality as form informs matter, and the part functioning as matter would not be active and operative per se, but only when it had its act by which it informed. Yet we see that both the diminished part of heat, which seems to be the matter, and the intensified part, which seems to be the form, are operative and actual. Nor can they be integral parts. First, because a form cannot be composed of such parts: it belongs to the nature of form to be a principle of a composite, not something principled and composite, but a simple principle. Also, composition of integral parts especially conflicts with a form or quality. Integral parts are material and belong to a thing by reason of its matter, as we will say below in q. 9,¹⁶ since integral parts agree in form and differ according to quantity: the quiddity and substance of a thing are preserved without any one of them, and thus the addition of an integral part does not add a form. But since form is that by which something is constituted as a principle, the addition of form in the mode of an integral part does not add the character of form; rather, it materializes the form itself and multiplies it according to something material, not formal. In this way it does not make the form more perfect and more such in its character as form, which belongs to intensification; it multiplies it materially, which belongs to extension. Nor can one say that these are integral parts by likeness, in the way that St. Thomas and theologians assign integral parts to virtues in ST II-II, qq. 48, 128, and 143. For these integral parts do not intensify virtues, but signify certain conditions or dispositions, or habits joined to a more principal virtue, giving rise to diverse operations. These can also be found in a diminished virtue: temperance has honesty and modesty, fortitude confidence and magnificence, and prudence memory and teachableness, even when the virtues are diminished. But an intensified and diminished quality do not differ in this way: both have the same character of activity or operation, though not the same mode of perfection; neither is one a condition or disposition for the other.

Finally, the conclusion is proved because the smaller the multiplication of entities, the more suitable it is to nature. Therefore, if intensification without the addition of a new form and entity is neither impossible nor unsuitable, such an addition is not to be posited. That it is neither impossible nor unsuitable will be further proved in the next conclusion, where we will show that a form can have a more perfect union without the addition of a new entity. This also better explains the form’s unity and simplicity: the less is added, the simpler it is in entity, though multiple in power. It belongs to the nature of intensification that the same form, while remaining the same, becomes more perfect and more powerful. Therefore, if this can occur through a greater communication of itself to the subject without adding a new entity, this will be more suitable to the nature of intensification.

I say, second: Intensification does not occur by adding some new mode that gives the form a new informative power or a new formal character of informing. Rather, it occurs through a new expression of the same form in the subject, removing the subject’s confusion and potentiality, reducing it to greater unity, and subjecting the subject more fully to that form. It follows from this that, if the form has a contrary, it expels it; intensification does not formally consist in this expulsion, however.

This is taken from St. Thomas in Sentences I, dist. 17, q. 2, a. 2, ad 3,¹⁷ where he says: “It is not of the nature of an intensified quality that it occur by removing a contrary; this happens to the quality only insofar as it is in a subject participating in a contrary. But it is necessary for intensification that the quality be brought from the imperfect to the perfect, as is clear in the transparent medium, in which there is nothing contrary to light, yet the light can be intensified according to an increase in the power that dominates. This imperfection arises from the potentiality of the nature itself, which is subjected to perfection and act. For since every receptive potency is open to many things, insofar as it is such it is dissimilar to the acting principle, which is determined to one act. As this conjunction of potentiality is more subjected to act, the act is perfected more perfectly, and what is perfected itself becomes more one and more assimilated to the acting principle.” Thus St. Thomas. In ST II-II, q. 24, a. 5, body and ad 3, he likewise explains that this intensification occurs by the subject being reduced more to act, and by the form being more present in the subject; for the form itself to become greater is for it to be more present in what receives it, not for another form to arrive.

To give and explain the basis of this conclusion, two things must be done. First, show that there is no incompatibility in the union and communication of a form to a subject having a range and varying without the addition of a new entity of the form. Second, show that this mode ought not add a new informative power, but only a new mode of communication and union.

The first point is clear from several examples. We see that the same quantity, without the addition of parts or a new quantity, can change its termination and mode of existence in a subject, as we will say below in q. 7,¹⁸ as happens in rarefaction and condensation. Likewise, the substantial form of the soul, without the addition of a new entity, can express and unite itself in different ways to matter arriving through nutrition, and provide one effect in one part and another effect in another. In the eye it gives the power of seeing; in the hand, of touching. It can be deprived of one effect but not another, and then provide again the effect it lost if the matter is suitably disposed. Thus it is also not incompatible for the same quality to actualize a subject in different ways through its communication of itself and to express its effects in matter in different ways, according to the range it has. A sign of this is that the contrariety of forms can be removed more or less perfectly. Therefore it is not incompatible for the whole form to be communicated to a subject, but not totally and according to every mode or effect it can provide it; in this way it can assimilate the subject to itself more or less and reduce the subject’s potentiality to the unity of actuality. Likewise, God seems to be seen in his entirety by each blessed person, but not totally; therefore he can be united and communicate himself in different ways, without adding an entity, through a greater expression of the same one. Similarly, we see in grace that, when united to one subject, it expresses an effect—for example, making someone an adopted son—that it cannot produce in another subject, such as Christ, because of the person’s incapacity. A visible species in the air informs its subject representatively and intentionally not at all, but only entitatively; in the eye it also informs intentionally, without any addition of an entity. Many similar examples are available, which clearly show that the same form, without an entitative addition, can express diverse formal effects, or the same effect in different ways, because of the subject’s diverse disposition, by which it is subjected to the form in different ways. Indeed, I add that even if intensification occurred by adding one form to another, union would still have to vary. When one part is added to another and one form is made from both, the union that previously united and only modified the antecedent form cannot modify and affect the new form made from both. Therefore a new union must be given, just as a new form is compounded, unless perhaps one says that several partial unions of different parts of the same form remain. Yet that does not remove the need for one total union, compounded from all of them, just as there is one form made from all those parts. Union corresponds to form; therefore, just as the total form is different, the corresponding union must be varied.

The second point is explained as follows. In defending St. Thomas’s opinion, there are two ways of speaking. Some posit that through intensification a new mode is produced that belongs not only to the side of union but also to the form itself or the informing principle, so that it adds to the form a new actuality and power to inform more perfectly than before the mode. They distinguish this mode from the union itself, from existence, and from inherence, and call it the mode of rooting. Their basis is that no form can provide a more perfect formal effect unless it is more perfect and actual in itself as the “that by which” principle, either entitatively or modally. Therefore, besides the union, the form itself must be made more perfect and actual through a mode that gives it the power and actuality to inform.

Others say that the mode newly produced or resulting through intensification adds nothing of actuality or informative character to the form itself, but belongs only to the side of the form’s union and expression in the subject.

The first way of speaking is not so suitable and does not seem to preserve St. Thomas’s meaning perfectly; rather, it seems partly to fall back into the opinion under attack, that an entity is added to the form being intensified in order to make it more intense. For if the form itself, when made more intense, receives a greater informative power as a formal character, then it receives an addition of form, since the informative power is not something superadded to the form, but is the form’s very entity and actuality. A form does not inform or cause its formal effect by something superadded, as an efficient cause acts through an added power; it does so by communicating its own actuality and entity. Therefore to receive a greater power of informing is the same as receiving a new actuality or entity of the form. This is what the opposing opinion says: intensification occurs by adding a form or entity.

This is confirmed because that mode cannot perfect the power to inform that was in the diminished quality by adding an accidental informative virtue distinct from the form’s entity. A form causes only by communicating itself, not by an added power as an efficient cause. Therefore, if that mode functions as a form or formal character giving the formal effect of intensification, even though the diminished form gives its real effect through some reality, this cannot stand: the intensified form as a whole is a simple quality, not partly a quality and partly a mode, and its corresponding effects are real, not merely modal—for example, being a disposition for a substantial form or producing greater effects. Therefore these effects correspond to a real, not a modal, principle.

Finally, if the mode is a degree in the form’s intensification, since there is no greater reason for one degree than another, as all degrees increase through intensification, it follows that every degree—especially a definite aliquot degree—will be the formal effect of some mode, and what remains beyond all the degrees will be the effect of the form’s entity. But what is left in a quality beyond all its degrees? Certainly nothing.

Likewise, on this opinion the form is not intensified according to the same formal character. One of its formal effects will be real and, as it were, essential, proceeding from the form’s real entity; another will be modal and non-entitative, namely, the effect that belongs to increase. Thus the formal effects are not altogether of the same nature, and the form will not properly be said to be intensified, since it is not perfected in the same prior formal character insofar as it is real, but receives a new one that is modal. This opinion therefore does not differ much from the one that posits entitative parts through addition of degree to degree. It admits that the form giving a diminished formal effect is not sufficient in itself with respect to its very power or formal character of providing an intense effect, but requires the addition of a new formal character. It places this addition in a new mode, not in a new entity of the form.

If, however, that mode is posited as a condition, not as a formal character of informing, it cannot be distinguished from the inherence or communication of the form. A required condition can be nothing other than the application or conjunction to the patient, by which the form expresses and communicates itself to the subject in a more perfect way. Previously the whole form and formal principle were in the subject, but not totally. Therefore the mode subsequently acquired does not belong to the informative power or a new formal character of the form itself, but to a new mode that is a condition, namely, a new communication or application of that form. The form is then not only wholly in the subject, but totally and in a more perfect mode. Without this condition or application of the form it does not give that more perfect effect, which is indeed entitative, just as the form’s diminished formal effect is; it was already possessed in the form, because the whole form was there, but it was not expressed totally in the subject.

St. Thomas’s meaning is understood in this way: he constantly explains the form’s intensification through a new expression of the form itself in the subject, not through the addition of a new informative power. He says that intensification occurs by the subject being more and more terminated by the form and “participating in it more and acquiring a perfect mode of participation,” as in ST I-II, q. 52, a. 2; “by the subject being made more actual by the quality itself,” as in De virtutibus, q. 1, a. 11;¹⁹ “by the form being brought from the imperfect to the perfect,” as in the cited place in Sentences I, dist. 17;²⁰ and “by the quality being more present in and rooted in the subject,” in ST II-II, q. 24, a. 4, ad 3. These expressions indicate some mode that applies the form to the subject in different ways, not one that gives a new informative power and changes the form’s formal character.

If you ask: How is this union changed through intensification, without adding a new informative formal character, so that the mode is a new union, existence, and inherence of the form in the subject? We reply that union of a form with a subject is required for two things. First, so that one thing is constituted from form and subject. Second, so that through such union and conjunction the form has being in the subject, since it depends on the subject for existing.

As to this second point, no new existence is added to the quality, because no new entity is added; the whole entity of the form was already present in the subject, and consequently its whole existence was present, since existence follows the entity itself as produced outside its causes. Thus, since on our opinion the whole entity of the form is in the subject, even if it is not there totally, then even when it increases through intensification, its existence does not change, since its entity does not change. In this respect, then, the union or inherence does not change in its character as the medium giving existence to the entity of the form.

As to the unity that the form makes with the subject, the union itself increases or is perfected—or rather, the form, which is changed by a new action so that it affects the subject. The subject is in a certain potentiality and indetermination, and according to this it can be subjected to diverse forms, or to the same form, not in only one indivisible mode but either more confusedly and potentially or more actually and determinately, through reduction to greater unity and likeness with the form. St. Thomas explains this rooting in the cited distinction 17 as a greater reduction to unity and a diverse mode of terminating the subject’s dissimilarity, confusion, and potentiality in relation to the actuality and unity of the form. This is sufficiently accomplished by the union or inherence itself, since making unity and removing confusion or potentiality toward many things—which is opposed to unity—belong to union. Therefore the form is communicated perfectly to the subject when this unity is perfected through the union itself. This is to be more rooted: to subject the subject’s potentiality more fully to the form and reduce its indetermination or confusion to greater unity, like the root of a tree, which makes the tree firmer the further it penetrates into the ground.

But you will say: Union, as we said in Physics q. 6,²¹ is not a mode mediating between form and subject. Therefore, if greater intensification consists in greater union and union is not a mode, intensification will not occur by adding a mode, although St. Thomas expressly admits a mode in intensification, as is clear in ST I-II, q. 52, a. 2, ad 2.

We reply that in our opinion union is not a mode functioning as the formal character and medium of uniting, because form, which in itself is act, in itself has the formal character of making unity, whether accidental or substantial, according to the kind of form. Since the resulting unity is not modal but substantial or accidental, neither the formal character nor the medium of uniting is a mode; it is the form itself. We do not deny, however, that some mode can be found in the union, antecedent or subsequent, insofar as the extremes must be changed, or at least one extreme, so that it is united and made dependent and changed toward unity with the subject. The change itself, remaining passively in the united extreme, is also a mode subsequent to union. This belongs more to the dependence or state that the form acquires by the force of union than to the formal character or medium of uniting; it nevertheless belongs to intensification, because intensification provides more a state of the form in communicating itself than a formal power of informing.

Many try to draw St. Thomas into the contrary opinion, relying chiefly on the authority we have already explained above¹, where he says in II–II, q. 24, a. 4, ad 3, and De virtutibus, q. 1, a. 11, that those who say a quality is intensified by being more deeply rooted, and not according to its essence, do not understand their own words. Thus St. Thomas intends that intensification occur through the addition of entity, not through rooting alone. But we have already explained this authority above², and one should also consult St. Thomas, Quodlibet IX, a. 13³, where he says: “When we say that charity is increased according to its essence, an increase of the subject is denoted, so that the sense is that the essence of charity itself is increased, just as when we say that something white is increased according to its essence. But this does not designate the form specifying the motion, as if the sense were that it is increased according to its essence—that is, that its increase is a motion in being or in essence; in this way increase is said to be according to quantity.” See how St. Thomas interprets what it means to be increased according to essence: not by adding a new entity to the prior entity, as though the motion of increase had a new entity as its terminus, but because the essence itself is the thing that is increased. Nor is it an objection that St. Thomas sometimes denies that charity is the subject of increase. He denies that charity is called the subject of increase as though it were the subject of inherence, that is, the thing that supports and sustains it; he does not deny that it is the subject of modification, since the form itself is what is communicated to the subject in a distinct mode and is thus modified by that communication.

The argument from St. Thomas, Summa theologiae III, q. 7, a. 12, is even less weighty. There he expressly admits that there are degrees in heat; consequently, intensification would occur by adding a degree, not by rooting. Finally, they add the testimony of Aristotle, Physics IV, text 84⁴, where he says that “just as the cold becomes hot, and conversely, because the same thing that was in potency [becomes so], so too from something hot comes something hotter.” If Aristotle thus equates the emergence of something hotter from something less hot with the emergence of something hot from something cold, then, just as the latter occurs through the production of a new entity, so does the former. Nor is it enough to posit the emergence of a new mode, since this cannot be understood in real forms except through a new entity dependent on the subject. Therefore, wherever there is a greater emergence of form, there is production of an entity.

To this it is readily answered that, in the first passage, St. Thomas does not mean by “degree” a new entity added to the preceding entity, but a new participation of the same form in the subject. It is aptly called a degree because, just as the soul expresses itself in matter in different ways through the degrees it possesses, while its entity remains the same and it does not confer the same degree and formal effect on all parts, so a quality expresses its actuality to the subject in different ways. A different degree is not a different entity of the form, but the same form communicating itself and producing effects in a different way.

As to the second passage, it is said that something hotter comes from something less hot just as something hot comes from something cold—not with respect to the entity produced, but with respect to the entity of producing, since in both cases something new comes to be and there is a terminus a quo and a terminus ad quem. Yet when something becomes hot simply, it passes from potency to heat; when something less hot becomes hotter, it is not in potency to the form, but to a mode of participation in the form, as St. Thomas says in Summa theologiae I–II, q. 52, a. 2, ad 3. As for the claim that there is no emergence unless there is production, I distinguish: emergence of a form with respect to its entity cannot occur without production of an entity—I concede; emergence of a form with respect to its new expression and mode of participation in a subject cannot occur without production of an entity—I deny. What occurs is only an improvement of the form that has emerged, and only the production of a mode, not of the form’s entity.

The second argument is based on reason: intensification is a motion really distinct from the first production of a quality and is a true alteration; therefore it ought to produce a reality distinct from the first quality, and not merely some mode, because alteration is primarily and per se toward a quality, not toward a mode. Moreover, an intensified power, precisely insofar as it is intensified, has greater power to produce than one that is not intensified, since it produces more perfect effects. But a mode is neither a power nor something that produces real effects corresponding to it in a special way. Finally, a new mode of inherence or union cannot be given unless a new inhering entity is added; otherwise the same entity would inhere through two inherences. Therefore, what is added must be a distinct entity, just as the motion is distinct. Where motions are really distinct, their termini must also be really distinct; otherwise, if the entity were the same, the motions too would be identified with one another, since things that are really identical with a third are identical with one another.

This is confirmed by the following: otherwise, if intensification produced not a quality but a mode, the quality could be produced by the production of a mode alone. This is clear because the motion of intensification has no minimum, but begins successively, not through a first instant of being changed, but through a last instant of not being. Therefore, if intensification produces not an entity but a mode, a quality could begin through intensification from the last nonbeing of a degree, and so the whole quality would begin through modes.

The answer is that intensification is a motion really distinct from the first production of a quality, since it can proceed from a different agent and over a different period of time. It is likewise per se terminated at a quality, as a true alteration, but not at a quality absolutely and as to its entity; rather, it terminates at a quality under a certain mode, namely, as something to be perfected and improved. In this respect it is like transubstantiation, which is an action toward the body of Christ, although it does not produce that body absolutely, but under a new mode. Intensification differs from other motions in this: in the others, something distinct from what was already present is acquired, such as a new part in increase, a new “where” and place in local motion; but in quality, what was already present is improved and perfected. Hence it is not required to produce a new form, but to attain the same form under a more perfect mode. For motions or actions to be really distinct, their termini need not be really and entitatively distinct as though materially; it suffices that they be distinct formally. Otherwise, every mode produced in a subject, such as sitting or a “where,” would have to be produced by a distinct real action. When it is said that things identical with a third are identical with one another, this is understood, first, when they are identical with the third at the same time, and not at different times; second, when they are identical with the third both in thing and in account—that is, under the same account and formality—not when they are identical with it as it were materially and under different formalities, or insofar as something is virtually multiple, as St. Thomas understands in Summa theologiae I, q. 28, a. 3. Otherwise, that axiom would have many counterexamples.

As for the further claim that a quality, insofar as it is intensified, has more real effects corresponding to it, the answer is that these effects correspond neither to the quality considered in itself nor solely to the added mode of intensification, but to the real entity of the form itself as it is subject to that mode. Therefore, for a power or form to produce new effects, the addition of an entity is not required; the same entity under a different formality and communication of itself suffices. The same soul, for example, produces different real effects according to its sensitive degree than according to its vegetative degree, yet it does not require a new entity to be added for those effects; rather, the same soul is communicated in matter in a different way.

As for the claim that a new inherence requires a new entity, the answer is that a new inherence of a form not previously present in a subject does require a new entity of the form. But a form already present in a subject does not require a new entity; it communicates the same form to the subject in a new mode of participation. Thus it does not so much give a new inherence absolutely as a new termination of inherence, as will be said in the final argument.

To the confirmation, the answer is that if intensification does not find a quality in the subject but produces it there for the first time, it produces not only a mode but also an entity. But if it finds the quality already produced, it adds only a new mode and not a new entity, just as transubstantiation would produce the body of Christ substantially if it did not presuppose that body as existing in reality; as matters stand, however, it does not produce it, but converts bread into it under a new mode.

The third argument is this: where there is real separation, there is real distinction. But one degree is separated from another—for example, the second from the third or fourth—as is evident in the remission of a quality. Therefore these degrees are really distinct, especially since we see that the continuation of heating resembles the first production and is of the same species, and is a true and proper action and change. It therefore requires a real terminus and entity, for there is no change without novelty and no action without a produced terminus.

This is confirmed as follows: the activity of an agent’s power becomes greater by the addition of parts and by an increase in the quantity of the form, just as glowing iron acts more actively than a flame of straw. Therefore intensification too occurs by the addition of parts, since that is what makes a power more active.

The answer is that degrees are never separated from a quality; rather, the quality is separated from them—that is, from each one taken separately, though not from the whole collection. This is a sign of modal distinction, as a body is separated from each position or “where,” but no “where” is separated from the body. As to what is said about the continuation of heating, the answer is that it is continued by reason of the quality or form itself as participated, and so it is an action of the same account as the first production of the quality. It is nevertheless different on the part of the mode of participation, and a distinct real action and change are required to produce such a mode. For modes too are produced by real action, as we have said—for example, “where,” position, and similar things. Thus such a change occurs with a newness of being, at least in the mode that is the produced terminus.

To the confirmation, we shall answer in the next question, when treating action and reaction⁵, and in question 7, when treating density⁶, where we shall show that there is no greater intensification of a quality by reason of density—that is, by reason of the multitude of parts—unless the agent, by occasion of those parts, produces a more intense quality. In itself, the multitude of parts contributes only to the conditions of activity, namely, that the agent acts more quickly or through a more perfect application. Once these conditions are in place, however, the agent can produce a more perfect and more intense quality, as we shall explain there at greater length.

The fourth argument is that intensification cannot occur according to a more perfect mode of union or inherence; therefore it must consist in the addition of some new entity.

The antecedent is proved as follows. The union and inherence of a quality is not divisible but always the same, because it inheres naturally in its subject, and so it inheres as much as it can. Likewise, it inheres and is united as a whole. Therefore it is not apparent how this union could grow, especially when the entity of the quality is indivisible—as in a spiritual quality—and it is intensified in the very same indivisible subject. Moreover, in remission itself it is not apparent what produces the lesser union or rooting of heat. When heat of degree six is remitted down to degree two, there is no source from which the union of heat of degree two might be produced. It is not produced by the agent that remits it—for example, water remitting the heat—since this is rather a contrary agent, which cannot produce heat of degree two. Nor is it produced by some other agent, such as fire or air, because they do not contribute to that remission, if the case is one in which no fire is nearby and only water remits the heat. Besides, if each gradual mode—for example, degree two or degree four—were indivisible, then, when it is remitted, either the whole union would perish or nothing would perish. If the whole union perishes, remission will be corruption, because when the whole union perishes, the whole united form perishes. If nothing perishes, the quality remains intensified.

This is confirmed by the following: if intensification consists in a greater union, then an intensified quality will not be able to be separated from its subject, since, while the union remains, it cannot be separated, and it can be separated only when the union is removed. Therefore, if intensification consists in union as intensified, it will not be separable. Thus, if God were to separate the whiteness of snow and the whiteness of a human being, the former would not be more perfect than the latter.

The answer is that this union has some latitude, as was shown above by several examples. When it is said that a quality inheres naturally as much as it can, I distinguish: as much as it can according to the requirement of the subject and the disposition of the agent—I concede; as much as it can absolutely by the force of the form—I deny. Since such dispositions are required for a quality to be intense, natural union always does as much as it can according to the requirement of the subject and its capacity. But when all impediments are removed and the disposition required on the part of the agent and patient is in place, the quality cannot fail to be intensified. This intensification then does not occur without an intrinsic perfection of the quality, because the very ordering of participation to a subject disposed in this way is something intrinsic to the quality.

To the other part of the argument—what produces a degree of remission when the intensifying agent has been removed—I say that it proceeds from two causes. One is per accidens: the cause that impedes that more perfect and intense mode of union, insofar as it renders the subject indisposed and unfit, just as one who removes the dispositions required for the soul to be in the body kills a human being. The other cause is per se: the form itself, from which the more remiss mode emanates by virtue of the prior action by which the agent that produced it united it to the subject. Although the producer’s action is not formally present now, it remains virtually as long as the produced form remains, since that form was its terminus. The form was united to the subject by that stronger and more perfect union in such a way that it virtually retains a lower, more remiss union if the dispositions for the more perfect union are removed, because the less perfect is virtually contained in the more perfect. It is like removing the point that terminates a line, whereupon another point results by virtue of the prior production of the quantity. These modes of intensification are like certain terminations by which the form more fully terminates and subjects the subject’s potentiality to itself. Which degree results—two or three, for example—is determined by the greater or lesser impediment from the contrary agent and the disposition of the subject.

Finally, as to what is added about that mode, if it is indivisible, the answer is that this union is indivisible entitatively, just as the form itself is, but divisible virtually. As we said above⁷, in respect of the unity that the form makes with the subject and the actuality by which it reduces the subject to its own likeness, the union admits of more and less. For although the form is united as a whole, it is not united totally. Thus it is consistent for it to be indivisible entitatively but divisible relatively, or virtually, since the form is not united under every relation and formality in which it can be participated, even if it is united as a whole; we shall explain this more fully in the next argument.

To the confirmation, the answer is that an intensified quality can be separated. It is called intense not because of its actual union with the subject—for this is destroyed when separation takes place—but because of its ordering and aptitude toward the subject, in which it seeks to inhere not just anyhow but with this or that mode of participation, which pertains to the quality’s intensification. Thus, just as inherence does not remain actually in a separated accident, but remains as an aptitude by which it regards the subject to which it is due—and this relation is actual, not potential, in the separated accident itself, even though inherence itself is not actual—so too there remains the relation of this or that mode of inherence, according to which intensification takes place. Although the quality does not actually have that union, it does actually have the relation and aptitude to be united in that way. By reason of this, it is called actually intense in relation to the subject—not the subject to which it is actually united, but the subject it actually regards and to which it is due—to be united as a single actuality in that mode.

The final argument is this: by explaining intensification through this rooting, we do not avoid the difficulties of the other opinion, which posits intensification through the addition of parts. For either we posit many unions in the same form, which is thus rooted and expressed in the subject, or one union. If many, then we already admit in the same subject many modes numerically distinct, something the other opinion intended to avoid when it refused to posit many numerically distinct accidents in the same subject. If one, it is either divisible or indivisible. If indivisible, then, when intensification or remission occurs, every union will be corrupted, since intensification consists in a greater union and consequently corrupts the lesser. If divisible, the whole union is corrupted. But when the union is corrupted, the united form is corrupted; thus we fall into the opinion that said intensification occurs by the corruption of one part and the addition of another.

Furthermore, if each motion of intensification is indivisible, then it cannot terminate a motion of intensification, since motion requires not only indivisibles but also parts, being itself divisible.

Nor can one say that the union is indivisible entitatively and divisible virtually. For since the quality is said to be intensified with respect to its modes and not with respect to its entity, and we say that these modes are unions, we must posit divisibility and latitude in the modes themselves. But if we posit that they are indivisible entitatively and divisible virtually, another mode of such union will remain by which it is made divisible, and the same argument will again be made about that mode—whether it is divisible or indivisible—and so on to infinity. If instead one says that the union is divisible into parts, the foundation of our opinion collapses. For we now posit parts in the union; if this is not incompatible with its individuation in the same part of the subject, why would it be incompatible for distinct parts of the quality to be present in the same part of the subject? Indeed, an argument against our opinion follows from this, because through the motion of intensification not only indivisibles but also parts are acquired, in accordance with the distance and latitude it has. Therefore, after it has acquired a degree of two, for example, it cannot immediately afterward acquire something indivisible, but something divisible. That divisible thing is either a part of the mode or of the quality. If it is of the quality, we have what we intended to prove; if it is of the mode, then the mode is divisible and, consequently, so are the things united.

The answer is that the union of an intensifiable quality is one and the same entitatively, just as the form united by it is one and the same, to which it is altogether proportioned; but it is divisible terminatively and relatively, insofar as it makes a greater or lesser unity of the subject with the form, because the subject is more assimilated to the form and the confusion of potentiality in the subject is removed, reducing it to greater subjection to the form itself. This is to make a greater unity and agreement with the form.

For, as we said above⁸, the form obtains two effects through union. The first is to have existence dependently on the subject to which it is united. In this respect, as we said, the union does not vary, because existence follows the very entity of the form, which entity remains indivisibly the same, as was said. The second effect is to make unity and agreement with the subject. In this respect it admits of latitude—not in the entity of the union itself, which is not distinct from the form, but in the termination and relation of greater agreement. Nor does this posit a mode of a mode or lead to infinity; rather, the united quality itself is perfected in different ways in the unity made by the union, with respect to its termination, by which its agreement with the subject is made greater as the confusion of potentiality is reduced to the unity of the form. Thus no further mode of union remains, but only another effect of the union itself, according to a different termination toward the subject and a different unity it makes with it. The union is divisible in this termination, or effect of participation and agreement; this is to be divisible virtually—that is, by reason of its effect and termination—whereas to be divisible entitatively is to be divisible on the part of the entity, or united form. These effects or terminations are not many at once in the subject, but occur successively, because when the quality is intensified, the preceding termination of the remiss degree is destroyed and a new, more perfect one is acquired, which contains the whole account of the preceding degree. It is like a quadrilateral containing a triangle, or a six-sided figure containing a three-sided one; and like a quantity that grows, where the prior termination is destroyed and a new one introduced. Two terminations are not present at once, nor are two figures. Thus it is never the case that two modes or two terminations distinct only numerically are present at once in the same part of the subject.

To the objection based on the motion of intensification, the answer is that, although each gradual termination is indivisible, passage from one termination to another occurs by way of latitude and distance in becoming—not because there are parts of the quality to be acquired between one mode and another, but because the mode being acquired, while it is in the process of becoming, is in a divisible mode, whereas in its completed state it is in an indivisible mode. In local motion, for example, the instant of being moved is indivisible, and between two such instants there are no permanent parts, but rather a flow and process of becoming, terminated and constituted in its completed state by the instant of being moved. The passage is not immediately from one indivisible to another; it is mediated by a flow and process of becoming that has a latitude to be traversed. Therefore, neither in local motion nor in alteration is it necessary to assign several partial unions or several permanent parts of a quality simultaneously existing in its completed state. There is only the process of becoming and tendency by which one passes from one terminus and instant of being moved to another through a flow and tendency. When an alteration occurs in a quality from one extreme to another, or from a quality of one species to a quality of another, and passage occurs through several intermediate species, there is motion between each pair of intermediate species, and yet intermediate parts are not acquired; rather, passage is made from one species to another. The intermediate is not a partial species found there; instead, the very process of becoming of the quality and the flow tending from one extreme to another is the latitude to be traversed by motion, because between every completed state there is a process of becoming. If, then, it is not necessary in intensification to identify indivisibles and permanent entitative parts, with one added to another and composing with it, but it suffices to posit a successive passage and flow or process of becoming from one termination to another, then just as, when one terminating surface in a quantity is removed and passage is made to another, immediately afterward one does not find a termination—for a part follows immediately afterward—but rather a tendency toward a termination, that is, toward another surface. What the proponents of the contrary opinion say about permanent parts of a quality and indivisibles joining them makes the quality like a continuum and like the mode of extensive increase in quantity. St. Thomas said that those who think a quality is increased by addition imagine it in this way, in I Sentences, d. 17, q. 2, a. 2⁹.