In De ente et essentia D. Thomae Aquinatis commentaria

Whether undetermined dimensions precede substantial form in matter. Averroes’s opinion on the Substance of the Orb, chapter I, column 2; Physics I, chapter LXIII; and Physics IV, chapter XXV.

The fourth [doubt], since it concerns the nature of accidents, whose treatment we are undertaking, I do not think should be entirely passed over. Three things must be done concerning it: first, Averroes’s opinion will be recounted; second, the opinion of St. Thomas will be set forth; third, the arguments on the contrary will be answered.

Regarding the first, it must be known that Averroes founded the opinion contrary to ours in his book On the Substance of the Orb, positing undetermined dimensions in prime matter, which is pure potency. From this it follows that not every accident is subjectively in a being in act.

He is moved to hold this by several arguments leading to an impossibility. The first is: An undetermined dimension is not coeternal with matter; therefore a body comes to be from what is not a body, and a dimension from what is not a dimension; and finally it follows that bodily forms, that is, dimensions, are contrary to one another and succeed one another in a subject, just as substantial forms succeed one another in the same matter. The consequence is impossible; therefore, by destruction of the consequent, and so on. The impossibility of the consequent is clear from the fact that neither motion nor any change is toward an undetermined quantity. For increase is toward a determinate quantity. It is also clear from the fact that nothing is contrary to quantity, as is said in the Categories. The consequence is proved from the fact that everything which comes to be comes to be from its contrary or privation, as is said in Physics I, text LXIV, and V of the same work, text VII.

The second argument is this: Undetermined quantity is not in matter; therefore matter cannot receive forms distinct in species or number at the same time. The consequent is false to the senses; therefore. The consequence is proved from the fact that diverse forms cannot be received at the same time except in diverse parts of matter; but matter lacks diverse parts before receiving quantity. For substance, with quantity excluded, is indivisible, as is said in Physics I, text XV.

The third argument is this: Quantity is not subjectively in matter; therefore form is not divided by the division of matter. The consequence holds because form is received in indivisible matter, since matter is posited as lacking quantity. Further: therefore a form received in matter has no division. The consequence holds because every division of a material form presupposes diversity of parts in matter. Further: therefore a form received in matter is eternal and lacks a contrary. The consequence holds because the temporality of a form follows its corruptibility; but no form is corruptible unless its receptacle has diverse parts, one of which is informed by that form and the other by another form. For things that mutually corrupt one another must be communicated in matter, as is said in On Generation I, text LIII. Finally it follows that matter receives no form except the first; for the corruption of one must be the generation of another, as is said in On Generation I, text XVII, and consequently it lacks a contrary. So much for the first point.

Although St. Thomas follows this opinion in some of his books, he ultimately determined the opposite as his own opinion in the First Part, question LXXVI, article 6, where he uses this argument against Averroes’s position: Whenever something is in potency to every act, it first receives, in a certain order, the first act absolutely and then the subsequent acts; but prime matter in itself is in potency to all substantial and accidental acts in a certain order; therefore it first receives the act that is prior absolutely, and then the later one. But the first act absolutely, also in the order of generation, is being; therefore the first thing understood to be received in matter is substantial being, and this is received only from substantial form; therefore substantial form is received in matter before any accident, and thus every accident that follows comes to a being in act.

That being is the first act absolutely is clear both from the authority of the Book of Causes at its beginning and because being as to quantity presupposes being, and likewise being as to quality presupposes being; and so with the others. Moreover, many inconveniences follow from this position: namely, that being in a certain respect precedes being absolutely; that being per accidens is prior to being per se; that matter has a greater connection with a form of another genus than with a form of its own genus, since it can be stripped of any substantial form but not of every accidental form; and that generable substances have not only three but four principles, namely matter, form, privation, and undetermined quantity. For it cannot be imagined that quantity is not a principle at least per accidens, since it is joined to a per se principle, just as privation is said to be; and thus Aristotle ought to have counted it among the principles. Therefore St. Thomas’s opinion must be held: every accident is subjectively in a being in act, and by this differs from substantial form, which is subjectively in a being in pure potency. And so much for the second point.

To Averroes’s first argument it is said that the first consequent of those arguments has several senses and is sometimes true and sometimes false; therefore it must be distinguished. If the word “from” signifies the relation of material cause, it is true: a body comes to be from matter which is not a body and is indivisible in act, although it is a body and divisible in potency. But if “from” signifies the relation of the terminus from which, it is false: the matter from which a body comes to be must, immediately before that instant, have had corporeity. And universally, at every instant of time, it must itself be under dimensions. In this sense Aristotle in On the Heavens III, texts XXIX and LXIV, says that it is impossible for a body to come to be from what is not a body, that is, after what is not a body. Further, the phrase “comes to be” must be distinguished: it can be understood in two ways of a body or dimension. In one way terminatively, that is, as coming to be as the terminus of some motion or change; and in this way it is impossible for a dimension to come to be. In another way concomitatively, as being a consequence accompanying the terminus itself of motion or change; and in this way it is true that a body comes to be. For neither generation, alteration, nor local motion terminates at quantity as such, although increase terminates at perfect quantity. But when generation terminates per se and primarily at a substantial composite, its inseparable accidents are generated consecutively; quantity is among these, and it follows substantial corporeity.

The error, then, occurs in Averroes’s first argument: once the first consequence is granted, insofar as it infers the consequent in one sense, the second consequence does not hold, since it presupposes that dimensions come to be not concomitatively and per accidens but terminatively. For what comes to be as the terminus of changes is said to be corrupted by its contrary and to succeed one another by mutually expelling one another; this is not said of what comes to be consecutively, among which is undetermined quantity.

To the second argument the consequence is denied. In reply to its proof, it is said that diverse forms requiring diverse parts in matter can be understood in two ways. In one way, so that “before” signifies an order of time: in this sense it is true that any two forms to be received simultaneously in matter presuppose that it was divided into several parts immediately before the instant at which those forms are introduced. For the same part of matter cannot at once be suitably disposed for two forms by alteration. But this previously required distinction of the parts of matter need not be made through undetermined dimensions inhering in matter itself; it is made through the dimensions of preceding composites. In another way, “before” can signify an order of nature, so that at the instant when the forms are introduced it is necessary that matter have, by nature, a diversity of parts prior to the distinct forms. This is false: matter must by nature be prior to being distinct. Therefore, at and for that instant, two forms require distinct parts of matter, but they do not presuppose them.

To the third it is said that form’s being divided through the division of its subject can be understood in two ways. In one way, form has division from the subject because it is received in matter already divided; in this way, how it is true and how it is false has just been explained. In another way, form is divided upon the division of its subject because it has such division by reason of its subject; in this way it is true, since quantitative division belongs to substantial form from the fact that it is in matter, by reason of which the composite is quantified.

For just as quality follows the composite by reason of form, though not in such a way that the quality itself is subjectively present in the form, so quantity is in the composite by reason of matter, though not in such a way that it is present in matter. Therefore, since quantitative division belongs to form only by reason of matter, in which it is received, as forms separated from matter show, we concede that forms are divided upon the division of the subject, but not that this division precedes form; rather, it accompanies it. Hence the answer to the entire course of the argument is clear, since it collapses by resting on a false foundation. For it is founded on the claim that, according to our exposition, forms are not divided upon the division of the subject; and it is clear that this does not follow.

The fifth doubt, with the arguments omitted, has a true affirmative part according to St. Thomas’s teaching. Since some being flows from every form, because form is that which gives being to a thing, accidental being must flow from an accidental form, as being-white flows from whiteness and being-sweet from sweetness.

That the being which flows from an accidental form is not the same as substantial being is most evident from the proper accounts of substance and accident. For substantial being is being absolutely, according to itself, independent, and first; accidental being is being in a certain respect, dependent upon a subject in another, and posterior. Not only is the accident’s being of actual existence really distinct from the subject’s actual being, but it is also distinct from the very essence of the accidental form from which it comes. For it was proved above that no created quiddity is its own existence. Hence the existence of whiteness is neither whiteness itself, nor the existence of the subject, nor the reception of whiteness in the subject. Likewise the existence of substantial form is neither the form itself, nor matter, nor the reception of form in matter. Rather, just as substantial form, received in matter, perfects it so that both receive existence, so whiteness, received in a subject, perfects it so that it receives being-white. Thus, just as form is the reason why matter and the substantial composite have being, so whiteness is the reason why the subject, the composite of whiteness and subject, has such being, namely being-white. And just as there must be as many substantial beings in a thing as there are substantial forms, so accidental being is multiplied according to the number of accidental forms. Being-white is one thing, and being-sweet another. Therefore those who attributed to St. Thomas the opinion recounted by Scotus in IV Sentences, distinction XXII, are mistaken.

Concerning the sixth doubt, namely whether a substance subject to an accident can be understood to exist without any accident, the position of the holy Doctor must first be explained. Then a certain error must be eliminated.

To grasp the first point, it must be distinguished that we can speak of substance and accident in two ways. First, simply as such: of substance under the account of substance and of accident insofar as it is accident. In another way, we can speak of substance and accident under the account of this substance and this accident. In the first way substance is separable from every accident, because substantial being as such has no necessary connection with accidental being; otherwise every substance would be subject to an accident. In the second way substance cannot be separated from every accident: it cannot be separated from its proper property, because of the necessary connection between a subject and its proper property—not because the subject depends upon the property. Therefore St. Thomas says in the Disputed Questions on Spiritual Creatures, article last, reply to 7, and in the Questions on the Soul, article 12, reply to 7, that it is neither possible nor intelligible for a subject to exist without its proper property. In the text, however, speaking of substantial and accidental being as such, he says that a subject can exist without an accidental form arriving in it. He shows, by the nature of demonstration, that a subject cannot exist without a property: the conclusion which proves the inherence of a property in a subject must be necessary and impossible to be otherwise.

Here an intolerable error must be avoided, proposed by Antonio Trombetta in his Quodlibet, where he says that according to St. Thomas and his followers a subject is nothing but a material cause with respect to a property, and a property is an accident; from this it necessarily follows that a subject can exist without its proper property. The basis of this consequence is that every passive potency is a potency of contradiction; but a subject is only in passive potency with respect to a property; therefore it is in a potency of contradiction, and therefore can have the property and not have it. The major premise is found in Metaphysics IX, text XVII, and is also proved by reason as follows: The properties of being are distinct in such a way that one includes the negation of another; therefore potency includes the negation of act; consequently, insofar as it is potency, potency is not incompatible with existing without act; therefore every potency is a potency of contradiction.

Moreover, toward the same conclusion: The possible is intermediate between the necessary and the impossible; therefore, since the necessary regards being alone and the impossible non-being alone, the possible regards both being and non-being; and thus every potency, since the possible is spoken of through it, is a potency of contradiction.

Moreover, toward the same conclusion: Passive potency is toward being because it can receive being from another, namely an agent; but if it receives being from another, with that other excluded, insofar as it is in itself it is under non-being. If, therefore, passive potency in itself is under non-being and can have being from an agent, it necessarily follows that it is a potency of contradiction, namely a potency toward being and non-being.

The error occurs both in the principles and in the conclusion. In the principles: St. Thomas in the First Part, question LXXVII, article 7, expressly holds and proves that the subject is the cause of its proper property in three genera of cause, namely material, efficient, and final; hence the error of the minor premise is clear. Although the major premise is Aristotle’s, it is nevertheless badly understood and proved. For material potency is twofold: one is merely receptive, while the other is not only receptive but also passive, with the name “passion” extended to every kind of change. Merely receptive potency is necessarily coeval with its act, since if it existed before its act it would have to receive that act through some change, and thus would not be merely receptive with respect to it. Passive potency, however, is necessarily coeval with no act with respect to which it is passive, since it acquires every such act through change and consequently loses it through change; for everything generable is corruptible, as is said in On the Heavens I. Therefore the proposition “Every potency is a potency of contradiction” must be understood of passive potency, not of merely receptive potency. Both the sense itself and Aristotle’s text establish this gloss. To the senses it is clear that there is in the heavens a receptive potency for their shape, and yet such potency in them is not a potency of contradiction: the heavens are not in potency to another shape. Aristotle in the cited text of Metaphysics IX says that the heavens are not in potency to motion but only to its termini; yet it is evident that the heavens have a receptive potency for their motion. Thus he indicated that he was speaking of passive potency, since the heavens are in potency to the termini of motion. Therefore, since a subject has not passive but merely receptive potency with respect to its proper property—for no change intervenes between a subject and its property—the subject is not in a potency of contradiction with respect to the property; and so the conclusion drawn was false.

To the arguments by which the objector attempts to prove that proposition of every receptive potency, the response is as follows. To the first it is said that it is true that the properties of being are distinct in such a way that one includes the negation of another, because one is not formally the other: potency is not formally act. But it does not follow: therefore either can exist without the other. For this inference is invalid: “This is not that; therefore this can exist without that.”

To the second it is said that the possible, as distinguished against the necessary and the impossible, is taken from passive potency, not from merely receptive potency. Therefore it does not follow from this except that passive potency is a potency of contradiction, whereas the objector must prove that every receptive potency is a potency of contradiction.

To the third it is said that the first proposition brought forward there—namely, that potency is toward being because it can receive being from another, namely an agent—is true in one sense and false in another. If “can” signifies possibility as distinguished against impossibility, Aristotle says that it is false: its sense is that potency is toward being because it is not impossible for it to receive being from an agent. In this way the heavens would be in potency to motion, since they receive it from another. But if “can” signifies potency as distinguished against being in act, then the proposition is true. Something is in potency toward being because it can receive being which it does not yet have, just as something is in potency toward non-being because it can have the non-being which it lacks. But since every possible act that can be had is acquired by some potency only through change, we return to our position: only passive potency is toward being.

The other arguments by which the Scotists prove the separability of substance from every accident can easily be solved from what was said above. For they assume propositions whose falsity was explained earlier.

But since that which is called most and most truly such in each genus is the cause of those which come later in that genus, as fire, which is at the limit of heat, is the cause of heat in hot things, as is said in Metaphysics II, substance, which is the principle in the genus of being and has essence most and most truly, must be the cause of accidents, which participate in the account of being secondarily and, as it were, in a certain respect.

In this second part of the chapter, intending to explain the diversity of accidents among themselves, he first sets down the cause of accidents, so as to indicate their cause of diversity, with this conclusion: Substance is the cause of accidents. He proves it thus: What is most and most truly a being is the cause of the remaining beings; substance is most and most truly a being; therefore substance is the cause of the other beings. But such beings are accidents. The minor premise is clear from Metaphysics VII at the beginning. The major is taken from Metaphysics II, text IV, where it is said that universally whatever is most such in some order is the cause of all the others in that order, so that they may be: just as fire, which in the order of hot things is hottest, is the cause of all hot things being hot. In the text he uses the name of genus, just as Aristotle there uses univocation, because the truth of this proposition requires the cause to communicate with the effect in name and account, although the same thing may be so analogically. For it does not follow, “The heavens are the cause of all hot things; therefore the heavens are hottest,” though it would follow if the name “hot” belonged univocally to the heavens and hot things. Since, therefore, substance and accident agree analogically in the name and account of being, and substance is being most of all, it is the cause of all the others being beings.

This nevertheless occurs in different ways: because the parts of substance are matter and form, some accidents principally follow form and some matter. Since accidents are caused by the substance in which they are, and the diversity of effects comes from causes, he assigns the diversity among accidents a priori from the diversity of the parts of substance from which the accidents flow, and gives three distinctions.

The first, with its subdivisions, is as follows. Some accidents principally follow form, others principally follow matter. Among the accidents following form, some communicate with matter, while others are separate from matter. Among the accidents following matter, some follow it in relation to a general form, and others in relation to a special form.

The reason for the first division is that, since everything acts through that by which it is in act, and some species is always thought to move and act, as is said in Physics III, text XVII, operations and operative powers must follow form. Likewise, since everything undergoes and is changed by reason of matter, several accidents must follow it, such as those which inhere because of matter’s different complexion and subject it to motion, and so on. He added “principally” in the first division to distinguish it from “totally.” For no accident belongs to form alone or matter alone, but all belong to the composite. Indeed, even for intellection, not only the soul concurs but the whole composite of matter and form: it is Socrates who first understands. The sense of the division, then, is that some accidents follow form not as their total cause but as their principal cause, and some similarly follow matter as their principal but not total cause. Since the cause of all accidents is what truly is, namely complete substance, the cause of all is the composite of matter and form; but for some the principal root is form, and for others the principal root is matter. Just as in artificial things one feature belongs to the composite by reason of form and another by reason of matter—cutting belongs to a saw by reason of its form, hardness by reason of its matter—so in natural things something arises in the composite by reason of form and something by reason of matter. Thus in Socrates sensing and understanding are by reason of form, while masculinity is by reason of matter. The rule for discerning accidents following form from those following matter will be assigned below.

Some form is found whose being does not depend on matter, such as the intellectual soul. Matter, however, has being only through form. Hence among the accidents which follow form there is something which has no communication with matter, such as understanding, which is not through a bodily organ, as the Philosopher proves in On the Soul III. Some consequences of form, however, have communication with matter, such as sensing; but no accident follows matter without communication with form.

Here the first subdivision is set down together with its cause. Since the proper powers, properties, and operations of forms must be proportioned to the forms themselves, if the essence of the form depends on matter, its power and operation, since they are not the form itself from which they flow but are more perfect, must depend on matter. If the essence of the form is independent of matter, it must have some power independent of matter; otherwise nature would have made a form independent for no purpose. It would have made a nature elevated above matter in such a way that it could not act and consequently could not attain its proper end; for everything exists for the sake of its operation, as is said in On the Heavens II, text XVII. Since, therefore, there are two kinds of substantial forms—those dependent on matter, such as all material forms, and those independent of it, such as the human soul—there are two kinds of accidents following form.

Some accidents flow from a form dependent on matter, and they flow from it in such a way that they are nevertheless received subjectively in the composite; for this reason they are said to have communication with matter, such as sensing, vegetating, and the like.

Others flow from a form independent of matter as such. They flow from the form itself in such a way that they are received subjectively in the form alone; for this reason they are said not to have communication with matter, such as intellect and will, understanding, willing, and the like.

Nor should you think that we now contradict what was said above through forgetfulness. Both are true: namely, that every accident belongs to the composite, as we said above, and that some accident belongs to form alone, as we are now saying. For an accident’s belonging to something can be understood in two ways. In one way, as belonging to a complete elicitive and receptive principle; in another way, as belonging to a suppositum. In this second way every accident belongs to the composite whose being and becoming it is; hence the soul does not understand as a suppositum which acts, but Socrates does so through the soul. In the first way, however, some accident belongs to the soul itself and some to the composite. For the intellectual power is not subjectively in any bodily part composed of matter and form, but is subjectively in the essence of the soul alone; hence in On the Soul III, text IV, it is said that the intellect is the act of no body. The sensitive powers, however, are not subjectively in the soul alone, but in determinate bodily parts composed of matter and substantial form. Likewise, the complete elicitive principle of sensation is not the soul’s power alone, but the composite of bodily organ and power of the soul. The complete elicitive principle of intellection, however, is the intellectual power alone. Since an immanent operation is subjectively in its elicitive principle, understanding will be in the intellect alone as in its subject. For this reason St. Thomas elsewhere says that the soul understands as the eye sees: it sees as a complete elicitive principle, for “eye” names the composite of bodily organ and power of the soul. These statements do not contradict one another, then: every accident belongs to the composite as suppositum, and some accident belongs to form alone as complete elicitive and receptive principle. Although the entire discussion concerns accidents of material substances, it nevertheless indicates from these things the nature of accidents following a form independent of matter.

And note that before the subdivision of the other member is given, the text assigns the reason why there is not, for accidents following matter, a subdivision like that made for those following form—namely, that among accidents following matter some communicate with form and some do not. The reason is that there is not a twofold matter, one dependent on form and the other not, as there is a twofold form; for no matter can exist without form.

Nevertheless, among the accidents that follow matter there is a certain diversity. Some accidents follow matter according to the order which it has to a special form, such as masculinity and femininity in animals, whose diversity is reduced to matter, as is said in Metaphysics X. Hence, when the animal’s form is removed, these accidents remain only equivocally. Others follow matter according to the order which it has to a general form; and therefore, when the special form is removed, they still remain in it, as the blackness of skin remains in an Ethiopian because of the mixture of the elements and not because of the soul’s account, and therefore remains in him after death.

Here the division of the other member is set down as follows: Among the accidents following matter, some follow it in relation to a general form, and some in relation to a special form. Those accidents are said to follow matter in relation to a general form which belong to an individual of a higher genus by reason more of its matter than of its form. Thus this mixed body has blackness of skin not by reason of the form of the mixed body, but because its matter has undergone such a condition—for example, in a climate where the sun’s heat abounds. Those accidents, however, are said to follow matter in relation to a special form which belong to an individual of a lower genus or species more by reason of matter than of form. Thus this animal is masculine not principally by reason of its soul, but because such a property accompanied matter disposed for the soul—for example, because the matter was not fully subject to the dominance of vigorous semen. The sign that accidents are related in this way, namely that they follow matter according as it regards a form of a higher or lower genus, is that some of them of the same account remain in the corrupted composite, while others remain only equivocally. For the blackness of a living and dead human being is of the same account, but masculinity is not. The only cause of this is that masculinity follows the animal by reason of its proper matter; and therefore, when the animal is corrupted and only equivocally remains, masculinity, whose account includes animal, must remain equivocally. But whiteness, because it follows the matter of the mixed body remaining in the corpse according to the same definition, remains not equivocally.