The Divine Trinity

The Divine Trinity

The Divine Trinity The First Treatise on Faith

God

The existence of God Regarding the unity of the divine essence, we must first believe that God exists. This is a truth clearly known by reason. We observe that all things that move are moved by other things, the lower by the higher. The elements are moved by heavenly bodies; and among the elements themselves, the stronger moves the weaker; and even among the heavenly bodies, the lower are set in motion by the higher. This process cannot be traced back into infinity. For everything that is moved by another is a sort of instrument of the first mover. Therefore, if a first mover is lacking, all things that move will be instruments. But if the series of movers and things moved is infinite, there can be no first mover. In such a case, these infinitely many movers and things moved will all be instruments.

But even the unlearned perceive how ridiculous it is to suppose that instruments are moved, unless they are set in motion by some principal agent. This would be like fancying that, when a chest or a bed is being built, the saw or the hatchet performs its functions without the carpenter. Accordingly, there must be a first mover that is above all the rest; and this being we call God.

Aquinas's Shorter Summa

The immobility of God We clearly infer from this that God, who moves all things, must

Himself be immovable. If He, being the first mover, were Himself moved, He would have to be moved either by Himself or by another. He cannot be moved by another, for then there would have to be some mover prior to Him, which is against the very idea of a first mover. If He is moved by Himself, this can be conceived in two ways: either that He is mover and moved according to the same respect, or that He is a mover according to one aspect of Him and is moved according to another aspect.

The first of these alternatives is ruled out. For everything that is moved is, to that extent, in potency, and whatever moves is in act. Therefore if God is both mover and moved according to the same respect, He has to be in potency and in act according to the same respect, which is impossible.

The second alternative is also impossible. If one part were moving and another were moved, there would be no first mover

Himself as such, but only by reason of that part of Him which moves. But what is per se is prior to that which is not per se. Hence there cannot be a first mover at all, if this perfection is attributed to a being by reason of a part of that being. Accordingly, the first mover must be altogether immovable.

Among things that are moved and that also move, the following may also be considered. All motion is observed to proceed from something immobile, that is, from something that is not moved according to the particular species of motion in question. Thus we see that alterations, generations, and corruptions occurring in lower bodies are reduced, as to their first mover, to a heavenly body that is not itself moved according to this species of motion, since it is incapable of being generated, but rather is incorruptible and

God unalterable.'' Therefore the first principle of all motion must be absolutely immobile.

The eternity of God The further conclusion is evident that God is eternal. For everything that begins to be or that ceases to be, is affected in this way through motion or change. But we have just shown that God is absolutely immobile. Consequently He is eternal.'

Necessity of God's existence The same line of reasoning clearly shows that God necessarily exists. For everything that has the possibility of being and of not being, is mutable. But God is absolutely immutable, as has been demonstrated.' Therefore it is impossible for God to be and not 11 In scholastic terminology, generation is the acquisition of a form by a being and corruption is the loss of a form. Generation and corruption are substantial if the form acquired or lost is substantial, and are accidental if the form is accidental. The latter process is called alteration.

— rN Very likely St. Thomas did not intend to retain this chapter in the final form of his Shorter Summa. The chapter is extraordinarily short, and gives but one briefly worded argument. This argument is not very satisfactory, for it excludes only beginning and end from God. It does not touch on the perfect simultaneity of God's existence, although such simultaneity is the essential characteristic of eternity. On the other hand, chapter 7, "The everlasting existence of God," and chapter 8, "Absence of succession in God," taken together, do demonstrate God's eternity in a cogent way. Hence it seems that chapter 5 does not belong to the work as definitively planned by St. Thomas. See A. R. Motte, O.P., "Un chapitre inauthentique dans le Compendium Theologiae de S. Thomas," Revue

Thomiste, XLV (1939), 749-53.

13 Cf. chap. 4.

Aquinas's Shorter Summa to be. But anything that exists in such a way that it is impossible for it not to exist, is necessarily Being itself, ipswm esse. Necessary existence, and impossibility of non-existence, mean one and the same thing. Therefore God must necessarily exist.

Moreover, everything that has a possibility of being and of not being, needs something else to make it be, for, as far as it itself is concerned, it is indifferent with regard to either alternative. But that which causes another thing to be is prior to that thing. Hence something exists prior to that which has the possibility of being and of not being. However, nothing is prior to God. Therefore it is impossible for Him to be and not to be. Of necessity, He must be. And since there are some necessary things that have a cause of their necessity, a cause that must be prior to them, God, who is the first of all, has no cause of His own necessity. Therefore it is necessary for God to be through Himself. i The everlasting existence of God From all this it is evident that God exists always. For whatever necessarily exists, always exists; it is impossible for a thing that has no possibility of not being, not to be. Hence such a thing is never without existence. But it is necessary for God to be, as has been shown.'* Therefore God exists always.

Again, nothing begins to be or ceases to be except through motion or change. But God is absolutely immutable, as has been proved." Therefore it is impossible for Him ever to have begun to be or to cease to be.

'4 C£ chap. 6.

15 Cf. chap. 4.

God Likewise, if anything that has not always existed begins to be, it needs some cause for its existence. Nothing brings itself forth from potency to act or from non-being to being. But God can have no cause of His being, since He is the first Being; a cause is prior to what is caused. Of necessity, therefore, God must always have existed.

Furthermore, whatever pertains to anyone in some other way than by reason of an external cause, pertains to him of himself. But existence does not come to God from any external cause, since such a cause would have to be prior to Him. Therefore God has existence of Himself, per se ipsum. But what exists per se exists always and necessarily. Therefore God exists always.

Absence of succession in God Clearly, therefore, no succession occurs in God. His entire existence is simultaneous. Succession is not found except in things that are in some way subject to motion; for prior and posterior in motion cause the succession of time. God, however, is in no sense subject to motion, as has been shown.'° Accordingly, there is no succession in God. His existence is simultaneously whole.

Again, if a being's existence is not simultaneously whole, something can be lost to it and something can accrue to it. That which passes is lost, and what is expected in the future can be acquired.

But nothing is lost to God and nothing accrues to Him since He is immutable. Therefore His existence is simultaneously whole.

From these two observations the proper meaning of eternity emerges. That is properly eternal which always exists, in such a 16 Cf chap. 4.

Aquinas's Shorter Summa way that its existence is simultaneously whole. This agrees with the definition proposed by Boethius: "Eternity is the simultaneyoy ously whole and perfect possession of endless life.

Simplicity of God A similar course of reasoning clearly shows that the first mover must be simple. For any composite being must contain two factors that are related to each other as potency to act. But in the first mover, which is altogether immobile, all combination of potency and act is impossible, because whatever is in potency is, by that very fact, movable. Accordingly, the first mover cannot be composite.

Moreover, something has to exist prior to any composite, since composing elements are by their very nature antecedent to a composite. Hence the first of all beings cannot be composite. Even within the order of composite beings we observe that the simpler things have priority. Thus elements are naturally prior to mixed bodies.'® Likewise, among the elements themselves, the first is fire, which is the simplest of all. Prior to all elements is the heavenly

'T De consolatione philosophiae, V, prosa 6 (PL, LXIII, 858).

18 Aristotle and St. Thomas, along with the medieval Scholastics in general, made their own the theory of Empedocles, who taught the existence of four elemental bodies: earth, air, fire, and water. All composite bodies, which they called mixed, were thought to result from a combination of the primary elements. These philosophers also believed that a special locality corresponded to each of the elements: fire and air naturally tended upward, water and earth tended downward. Cf. Aristotle, Metaph., I, 8

(988 b 32); De caelo, I, 2 (269 a 17). St. Thomas likewise followed the curious view of Aristotle that heavenly bodies differ from terrestrial bodies in their nature, their movement, and their incorruptibility. Cf. Summa, la, q. 66, a.2; Aristotle, De caelo, I, 2 (269 a 12-b 17); 3 (270 a 12-35).

God body, which has a simpler construction, since it is free from all contrariety. Hence the truth remains that the first of beings must be absolutely simple.

Identity of God with His essence The further conclusion follows that God is His own essence. The essence of anything is that which its definition signifies. This is identical with the thing of which it is the definition, unless per accidens something is added to the thing defined over and above its definition. Thus whiteness is added to man, over and above the fact that he is a rational and mortal animal. Hence rational and mortal animal is the same as man; but whiteness, so far as it is white, is not the same as man.

In any being, therefore, in which there are not found two factors whereof one is per se and the other per accidens, its essence must be altogether identical with it. In God, however, since He is simple, as has been shown," there are not found two factors whereof one is per se and the other per accidens. Therefore His essence must be absolutely the same as He Himself.

Moreover, whenever an essence is not absolutely identical with the thing of which it is the essence, something is discerned in that thing that has the function of potency and something else that has the function of act. For an essence is formally related to the thing of which it is the essence as humanity is related to man. In God, however, no potency and act can be discerned: He is pure act.

Accordingly, He is His essence.

19 C£ chap. 9.

WS)

Aquinas's Shorter Summa I] Identity of essence and existence in God God's essence cannot be other than His existence. In any being whose essence is distinct from its existence, what it is must be distinct from that whereby it is. For in virtue of a thing's existence we say that it is, and in virtue of its essence we say what it is. This is why a definition that signifies an essence manifests what a thing is. In God, however, there is no distinction between what He is and that whereby He is, since there is no composition in Him, as has been shown." Therefore God's essence is nothing else than His existence.

Likewise, we have proved that God is pure act without any admixture of potentiality.'' Accordingly, His essence must be the ultimate act in Him; for any act that has a bearing on the ultimate act, is in potency to that ultimate act. But the ultimate act is existence itself, ipsum esse. For, since all motion is an issuing forth from potency to act, the ultimate act must be that toward which all motion tends; and since natural motion tends to what is naturally desired, the ultimate act must be that which all desire.

This is existence. Consequently the divine essence, which is pure and ultimate act, must be existence itself, ipswm esse.

God not contained under any genus We infer from the above that God is not contained as a species within any genus. Species is constituted by specific difference

20 Cf. chap. 9.

21 Thid.

God added to genus. Hence the essence of any species possesses something over and above its genus. But existence itself, ipsum esse, which is God's essence, does not comprise within itself any factor added to some other factor. Thus, God is not a species of any genus.

Furthermore, since genus potentially contains specific differences, in every being composed of genus and differences, act is commingled with potency. But we have shown that God is pure act without any commingling of potency." Therefore His essence is not composed of genus and differences; and so He is not in any genus.

God is not a genus We go on to show that God cannot be a genus. What a thing is, but not that it is, comes from its genus; the thing is established in its proper existence by specific differences. But that which God is, is very existence itself. Therefore He cannot be a genus.

Moreover, every genus is divided by some differences. But no differences can be apprehended in very existence itself. For differences do not share in genus except indirectly,"' so far as the species

22 Cf. chap. 9.

23 The word indirectly here and elsewhere is sometimes used to translate per accidens. Thus, in the present case, a species participates in genus per se, or directly and of itself, since it is a logical division of a genus. A specific difference, however, pertains to genus, not per se, directly of itself, but only so far as it is the determining factor of a species, distinguishing it from other species of the same genus; that is, it pertains to genus only per accidens, indirectly, through the species it constitutes. Another instance of this same meaning of per accidens is discerned in the death of a brute animal (Cf. ch. 84). What perishes per se or directly is the animal. The vital principle or form of the animal also perishes, but only per accidens, that is, indirectly or incidentally, because of the destruction of the animal.

Aquinas's Shorter Summa that are constituted by differences share in a genus. But there cannot be any difference that does not share in existence, since non-being is not the specific difference of anything. Accordingly,

God cannot be a genus predicated of a number of species.

God is not a species predicated of individuals God cannot be, as it were, a single species predicated of many individuals. Various individuals that come together in one essence of a species are distinguished by certain notes that lie outside the essence of the species. For example, men are alike in their common humanity but differ from one another in virtue of something that is outside the concept of humanity. This cannot occur in God, for God Himself is His essence, as has been shown." Therefore God cannot be a species that is predicated of several individuals.

Again, a number of individuals comprised under one species differ in their existence, and yet are alike in their one essence.

Accordingly, whenever a number of individuals are under one species, their existence must be different from the essence of the species. But in God existence and essence are identical, as has been demonstrated." Therefore God cannot be a sort of species predicated of many individuals.

1S) The unicity of God Thus it is evident that there can be but one God. If there were many gods, they would be called by this name either equivocally

24 CF. chap. 10.

25 Cf. chap. 11.

God or univocally. If they are called gods equivocally, further discussion is fruitless; there is nothing to prevent other peoples from applying the name god to what we call a stone. If they are called gods univocally, they must agree either in genus or in species. But we have just shown that God can be neither a genus nor a species comprising many individuals under Himself. Accordingly, a multiplicity of gods is impossible.

Again, that whereby a common essence is individuated cannot pertain to many. Although there can be many men, it is impossible for this particular man to be more than one only. So if an essence is individuated by itself, and not by something else, it cannot pertain to many. But the divine essence is individuated by itself, since God's essence is not distinct from His existence; for we have shown that God is His essence."° Hence God cannot be more than one only.

Another consideration is the following. A form can be multiplied in two ways: first, by specific differences, as in the case of a generic form (in this way, color is differentiated into the various species of color); secondly, by the subjects in which it inheres

(such as whiteness). Therefore any form incapable of being multiplied by specific differences cannot be multiplied at all, if it is a form that does not exist in a subject. Thus whiteness, if it were to subsist without a subject, would not be more than one. But the divine essence is very existence, ipsum esse, which does not admit of specific differences, as we have shown."' Since, therefore, the divine existence is a quasi-form subsisting by itself, seeing that God is His existence, the divine essence cannot be more than one.

Accordingly, a plurality of gods is impossible.

26 Cf chap. 10. aT GB dian 13;

Aquinas's Shorter Summa

God is not a body It-is evident, further, that God Himself cannot be a body. For in every body some composition is found, since a body has parts.

Hence that which is absolutely simple cannot be a body.

Moreover, we find that a body does not move anything else unless it is first moved itself, as will appear clearly to anyone who examines the matter fully. So if the first mover is absolutely immovable, that being cannot be a body.

God is neither the form of a body nor a force in a body God cannot be the form of a body or any kind of force existing in a body. For, since all bodies are found to be mobile, whatever is present in a body must be moved, at least per accidens or concomitantly, if the body itself is moved. The first mover, however, cannot be moved either per se or per accidens, for it must be absolutely immobile, as has been shown."® Therefore God cannot be a body or a force in a body.

Again, in order to move an object, every mover must have dominion over the thing that is moved. For we observe that motion is more rapid in proportion as the motive force exceeds the resisting force of the mobile object. Therefore that which is the very first among all movers, must predominate supremely over all the things moved. But this would be impossible if the mover were in any way attached to the mobile object, as it would have to be if it were the form or motive power of the latter. Consequently the 28 CE. chap. 4.

God first mover cannot be a body or a force in a body or a form in a body. This is why Anaxagoras postulated an intelligence liberated from matter, that it might rule and move all things."

The infinity of God according to essence This leads to the question of God's infinity. God is not infinite by way of privation, according to which infinity is a passion of quantity; in this sense whatever lacks limits, but is nevertheless capable of having limits by reason of its genus, is said to be infinite.

Rather, God is infinite negatively, in the sense that a being that is unlimited in every way is infinite. No act is found to be limited except by a potency that is receptive of the act; thus we observe that forms are limited in accordance with the potency of matter.

Hence, if the first mover is an act without any admixture of potency, as not being the form of any body or a force inhering in a body, it must be infinite.

The very order perceived in things is a proof of this. The higher the position occupied in the scale of being, the greater are things found to be in their own way. Among the elements, nobler things are found to be greater in quantity, as also in simplicity. Their generation demonstrates this: as the proportion of the respective elements is increased, fire is generated from air, air from water, and water from earth. And a heavenly body clearly exceeds the total quantity of the elements. Necessarily, therefore, that which is the first among beings and which has nothing above it, must in its own fashion be of infinite quantity.

29 See Anaxagoras, fragment 12 in H. Diels, Die Fragmente der Vorsokratiker (Berlin: Weidmann, 1922), I, 404; cf. Aristotle, Metaph., I, 3; 8 (984 b

15-22; 989 b 15).

Aquinas's Shorter Summa Nor is there anything to wonder at if what is simple and lacks corporeal quantity is said to be infinite and to exceed in its immensity all quantity of body. For our own intellect, which is incorporeal and simple, exceeds the quantity of all bodies in virtue of its knowledge, and embraces all things.

Much more, then, that which is the very first of all exceeds the universe of beings in its immensity, and embraces them all.

The infinite power of God The further inference is drawn that God is infinite in power. For power is consequent upon a thing's essence; anything whatever possesses a power of activity consonant with its manner of being.

Therefore, if God is infinite in His essence, His power must be infinite.

This is clear to anyone who will inspect the order of things.

Whatever is in potency, is thereby endowed with receptive and passive power; and so far as a thing is in act, it possesses active power. Hence what is exclusively in potency, namely, prime matter, has an unlimited power of receptivity, but has no part in active power. And in the scale of being above matter, the more a thing has of form, the more it abounds in the power of acting. This is why fire is the most active of all the elements. Therefore God, who is pure act without any admixture of potency, infinitely abounds in active power above all things.

Absence of imperfection in God's infinity Although the infinity discerned in quantities is imperfect, the infinity predicated of God indicates supreme perfection in Him.

God The infinity that is in quantities pertains to matter, in the sense that matter lacks limits. Imperfection occurs in a thing for the reason that matter is found in a state of privation. On the other hand, perfection comes exclusively from form. Consequently, since

God is infinite because He is exclusively form or act and has no admixture of matter or potentiality, His infinity pertains to His supreme perfection.

This can also be gathered from a consideration of other things.

Although in one and the same being that evolves from imperfect to perfect, something imperfect precedes the perfect stage (as, for example, the boy is prior to the man), everything imperfect must derive its origin from what is perfect. The child is not begotten except by a man and the seed does not receive existence except from an animal or a plant. Accordingly, that which is by nature prior to all other things and sets them all in motion, must be more perfect than all the rest.

2] Eminent existence in God of all perfections found in creatures The further inference clearly follows that all perfections found in anything at all must originally and superabundantly be present in God. Whatever moves something toward perfection, must first possess in itself the perfection it confers on others. Thus a teacher has in his own mind the knowledge he hands on to others.

Therefore, since God is the first mover and moves all other beings toward their perfections, all perfections found in things must pre-exist in Him superabundantly.

Besides, whatever has a particular perfection but lacks another perfection, is contained under some genus or species. For each thing is classed under a genus or a species by its form, which is the thing's perfection.

Aquinas's Shorter Summa gq But what is placed under species and genus cannot be infinite in essence; for the ultimate difference whereby it is placed in a species necessarily closes off its essence. Hence the very ratio or description that makes a species known is called its definition, or even finis. Therefore, if the divine essence is infinite, it cannot possess merely the perfection of some genus or species and be lacking in other perfections; the perfections of all genera or species must be in God.

Unity of all perfections in God If we gather together the various points established thus far, we perceive that all perfections in God are in reality one. We have shown above that God is simple.° But where there is simplicity, there can be no distinction among the perfections that are present.

Hence, if the perfections of all things are in God, they cannot be distinct in Him. Accordingly, they are all one in Him.

This will become evident to anyone who reflects on our cognitive powers. A higher faculty has a unified knowledge of all that is known through the lower faculties according to diverse aspects.

All that the sight, the hearing, and the other senses perceive, the intellect judges with the one, simple power that belongs to it.

Something similar appears in the sciences. The lower sciences are multiplied in accord with the various classes of beings that constitute their objects. Yet one science which holds the primacy among them is interested in all classes of beings. This is known as first philosophy. The same situation is observed in civil power: in the royal power, which is but one, are included all the powers that are

3° Cf. chap. 9.

God distributed through various offices within the jurisdiction of the kingdom. In the same way perfections, which in lower things are multiplied according to the diversity of these things, must be united in the pinnacle of being, that is, in God.

Absence of accidents in God It is also clear there can be no accident in God. If all perfections are one in Him, and if existence, power, action, and all such attributes pertain to perfection, they are necessarily identical with His essence. Thus none of these perfections is an accident in God.

Furthermore, a being to whose perfection something can be added, cannot be infinite in perfection. But if a being has some perfection that is an accident, a perfection can be added to its essence, since every accident is superadded to essence. Hence infinite perfection will not be found in its essence. But, as we have shown, God is of infinite perfection according to essence.! Consequently there can be in Him no accidental perfection: whatever is in Him, is His substance.

The same truth can be easily inferred from God's supreme simplicity, and from the fact that He is pure act and is the first among beings. For some sort of composition obtains between an accident and its subject. Likewise, that which is a subject of this kind cannot be pure act, since an accident is a certain form or act of the subject. Similarly, what is per se always precedes what is per accidens. From this we can infer, in keeping with the truths shown above, that nothing can be predicated of God as an accident.

31 Cf. chap. 18.

Aquinas's Shorter Summa

God's simplicity is not contradicted by the multiplicity of names applied to Him This enables us to perceive the reason for the many names that are applied to God, even though in Himself He is absolutely simple.

Since our intellect is unable to grasp His essence as it is in itself, we rise toa knowledge of that essence from the things that surround us. Various perfections are discerned in these things, the root and origin of them all being one in God, as has been shown." Since we cannot name an object except as we understand it (for names are signs of things understood), we cannot give names to God except in terms of perfections perceived in other things that have their origin in Him. And since these perfections are multiple in such things, we must assign many names to God. If we saw His essence as it is in itself, a multiplicity of names would not be required; our idea of it would be simple, just as His essence is simple. This vision we hope for in the day of our glory; for, according to Zechariah 14:9,

"In that day there shall be one Lord, and His name shall be one."

The names of God are not synonymous In this connection three observations are in order. The first is that the various names applied to God are not synonymous, even though they signify what is in reality the same thing in God. In order to be synonymous, names must signify the same thing, and besides must stand for the same intellectual conception. But when the same object is signified according to diverse aspects (that is,

32 Cf. chap. 22.

God according to notions which the mind forms of that object), the names are not synonymous. For then the meaning is not quite the same, since names directly signify intellectual conceptions, which are likenesses of things.

Therefore, since the various names predicated of God signify the various conceptions that our mind forms of Him, they are not synonymous, even though they signify absolutely the same thing.

Impossibility of defining God A second point is this: since our intellect does not adequately grasp the divine essence in any of the conceptions which the names applied to God signify, the definitions of these terms cannot define what is in God. That is, any definition we might formulate of the divine wisdom would not be a definition of the divine power (and so on regarding other attributes).

The same is clear for another reason. A definition is made up of genus and specific differences, for what is properly defined is the species. But earlier we have shown that the divine essence is not included under any genus or species." Therefore it cannot be defined.

Analogy of terms predicated of God and of other beings The third point is that names applied to God and to other beings are not predicated either quite univocally or quite equivocally.

They cannot be predicated univocally because the definition of 33 Cf. chaps. 12, 14, 15.

Aquinas's Shorter Summa what is said of a creature is not a definition of what is said of God.

Things predicated univocally must have the same definition.

Nor are these names predicated in all respects equivocally. In the case of fortuitous equivocation, a name is attached to an object that has no relation to another object bearing the same name.

Hence the reasoning in which we engage about one cannot be transferred to the other. But the names predicated of God and of other things are attributed to God according to some relation He has to those things; and in their case, the mind ponders what the names signify. This is why we can transfer our reasoning about other things to God.

Therefore such terms are not predicated altogether equivocally about God and other things, as happens in the case of fortuitous equivocation. Thus they are predicated according to analogy, that is, according to their proportion to one thing. For, from the fact that we compare other things with God as their first origin, we attribute to God such names as signify perfections in other things.

This clearly shows that, as regards the assigning of the names, such names are primarily predicated of creatures, inasmuch as the intellect that assigns the names ascends from creatures to God. But as regards the thing signified by the name, they are primarily predicated of God, from whom the perfections descend to other beings.

The intelligence of God We must now demonstrate that God is intelligent. We have already proved that all perfections of all beings whatsoever preexist in God superabundantly.* Among all the perfections found in beings,

34 C£. chap. 21.

God intelligence is deemed to possess a special preeminence, for the reason that intellectual beings are more powerful than all others.

Therefore God must be intelligent.

Moreover, we pointed out above that God is pure act without any admixture of potentiality." On the other hand, matter is being in potency. Consequently God must be utterly free from matter.

But freedom from matter is the cause of intellectuality. An indication of this is that material forms are rendered intelligible in act by being abstracted from matter and from material conditions. Therefore God is intelligent.

We proved, further, that God is the first mover.*° This very perfection appears to be a property of intellect, for the intellect, we observe, uses all other things as instruments, so to speak, in producing movement. Thus man, through his intellect, uses animals and plants and inanimate objects as instruments, of a sort, to cause motion. Consequently God, the first mover, must be intelligent.

God's intelligence is not potential or habitual but actual Since in God nothing is in potency but all is in act, as has been shown,' God cannot be intelligent either potentially or habitually but only actually. An evident consequence of this is that He undergoes no succession in understanding. The intellect that understands a number of things successively is able, while actually understanding one thing, to understand another only potentially.

But there is no succession among things that exist simultaneously.

So, if God understands nothing in potency, His understanding is 35 CF. chap. 4.

3© CF. chap. 3.

37 Cf, chap. 4.

WS)

Aquinas's Shorter Summa free from all succession. Accordingly, whatever He understands,

He understands simultaneously. Furthermore, He does not begin to understand anything. For the intellect that begins to understand something, was previously in potency to understanding.

It is likewise evident that God's intellect does not understand in discursive fashion, proceeding from one truth to a knowledge of another, as is the case with our intellect in reasoning. A discursive process of this sort takes place in our intellect when we advance from the known to a knowledge of the unknown, or to that which previously we had not actually thought of. Such processes cannot occur in the divine intellect. aU God's essence is the only species in His understanding

The foregoing exposition makes it clear that God understands through no other species than through His essence.

The reason is, that any intellect which understands through a species other than itself, is related to that intelligible species as potency to act. For an intelligible species is a perfection of the intellect, causing it to understand in act. Therefore, if nothing in God is in potency, but He is pure act, He must understand through His own essence, and not through any other kind of species.

In consequence of this, He directly and principally understands Himself. For the essence of a thing does not properly and directly lead to the knowledge of anything else than of that being whose essence it is.

Thus man is properly known through the definition of man, and horse is known through the definition of horse. Therefore, if God understands through His essence, that which is directly and principally understood by Him must be God Himself. And, since

God is His own essence, it follows that, in Him, understanding and

God that whereby He understands and that which is understood are absolutely identical.

Identity between God and His intelligence God must be His own intelligence. Since to understand is second act'® (for example, to consider), whereas the corresponding first act is the intellect or knowledge, any intellect that is not its own understanding is related to its understanding as potency to act. For in the order of potencies and acts, that which is first is always potential with respect to what follows, and that which is last is perfective.

This is true only with reference to one and the same being, for among different beings the converse obtains. Thus a mover and an agent are related to the thing moved and actuated as act to potency. In God, however, who is pure act, there is nothing that is related to anything else as potency to act. Accordingly, God must be His own intelligence.

Furthermore, the intellect is related to its act of understanding as essence is related to existence. But God understands through His essence, and His essence is His existence.

Therefore His intellect is His act of understanding. And thus no composition is attributed to Him by the fact that He understands, since in Him intellect and understanding and intelligible species are not distinct; and these in turn are nothing else than His essence.

38 In scholastic usage, first act (actus primus) designates the prime form of a thing, a faculty (such as intellect or will), or even a habit (such as habitual knowledge). Second act (actus secundus) denotes activity or operation. In general, first act may be said to be entitative and second act is operative. oa

Aquinas's Shorter Summa Q

The volition of God We perceive, further, that God must have volition. For He understands Himself, who is perfect good, as is clear from all that has been hitherto established. But good as apprehended is necessarily loved, and love operates through the will. Consequently, God must have volition.

Moreover, we showed above that God is the first mover." But the intellect, assuredly, does not move except through the intermediacy of appetite, and the appetite that follows intellectual apprehension is the will. Therefore God must have volition.

Do Identity of God's will with His intellect Evidently God's will cannot be anything other than His intellect.

For, since a good that is apprehended by the intellect is the object of the will, it moves the will and is the will's act and perfection. In God, however, there is no distinction between mover and moved, act and potency, perfection and perfectible, as is clear from the truths we have already gained. Also, the divine intellect and the divine essence are identical. Therefore the will of God is not distinct from the divine intellect and God's essence.

Another consideration is that among the various perfections of things, the chief are intellect and will. A sign of this is that they are found in the nobler beings. But the perfections of all things are one in God, and this is His essence, as we showed above." In God, therefore, intellect and will are identical with His essence.

39 Cf. chap. 3.

4° C£. chap. 22.

God

Identity between God's will and His willing Hence it is also clear that the divine will is the very act of willing in God. As has been pointed out,"" God's will is identical with the good willed by Him. But this would be impossible if His willing were not the same as His will; for willing is in the will because of the object willed. Accordingly, God's will is His willing.

Again, God's will is the same as His intellect and His essence.

But God's intellect is His act of understanding, and His essence is His existing. Therefore His will must be His act of willing. And so we see clearly that God's will is not opposed to His simplicity.

The foregoing truths are embraced in one article of Faith From all the details of doctrines thus far discussed, we can gather that God is one, simple, perfect, and infinite, and that He understands and wills. All these truths are assembled in a brief article of our Creed, wherein we profess to believe "in one God, almighty."

For, since this name God (Deus), is apparently derived from the Greek name Theos, which comes from theasthai, meaning "to see or to consider," the very name of God makes it clear that He is intelligent and consequently that He wills.

In proclaiming that He is one, we exclude a plurality of gods, and also all composition; for a thing is not simply one unless it is simple.

The assertion that He is almighty is evidence of our belief that He possesses infinite power, from which nothing can be taken

41 Cf chap. 32.

Aquinas's Shorter Summa away. And this includes the further truth that He is infinite and perfect; for the power of a thing follows the perfection of its essence.

The Holy Trinity

Philosophical character of this doctrine The truths about God thus far proposed have been subtly discussed by a number of pagan philosophers, although some of them erred concerning these matters. And those who propounded true doctrine in this respect were scarcely able to arrive at such truths even after long and painstaking investigation.

But there are other truths about God revealed to us in the teaching of the Christian religion, which were beyond the reach of the philosophers. These are truths about which we are instructed, in accord with the norm of Christian faith, in a way that transcends human perception.

The teaching is that although God is one and simple, as has been explained above," God is Father, God is Son, and God is

Holy Spirit. And these three are not three gods, but are one God.

We now turn to a consideration of this truth, so far as is possible to us.

42 Cf. chaps. 9, 15.

Aquinas's Shorter Summa of The Word in God We take from the doctrine previously laid down that God understands and loves Himself; likewise, that understanding and willing in Him are not something distinct from His essence. Since God understands Himself, and since all that is understood is in the person who understands, God must be in Himself as the object understood is in the person understanding.

But the object understood, so far as it is in the one who understands, is a certain word of the intellect. We signify by an exterior word what we comprehend interiorly in our intellect. For words, according to the Philosopher, are signs of intellectual concepts.*? Hence we must acknowledge in God the existence of His

Word.

The word as conception What is contained in the intellect, as an interior word, is by common usage said to be a conception of the intellect. A being is said to be conceived in a corporeal way if it is formed in the womb of a living animal by a life-giving energy, in virtue of the active function of the male and the passive function of the female in whom the conception takes place. The being thus conceived shares in the nature of both parents and resembles them in species.

In a similar manner, what the intellect comprehends is formed in the intellect, the intelligible object being, as it were, the active principle, and the intellect the passive principle. That which is

43 Aristotle, De interpretatione, I, 1 (16 a 3).

The Holy Trinity thus comprehended by the intellect, existing as it does within the intellect, is conformed both to the moving intelligible object (of which it is a certain likeness) and to the quasi-passive intellect

(which confers on it intelligible existence). Hence what is comprehended by the intellect is not unfittingly called the conception of the intellect.

Relation of the Word to the Father But here a point of difference must be noted. What is conceived in the intellect is a likeness of the thing understood and represents its species; and so it seems to be a sort of offspring of the intellect.

Therefore, when the intellect understands something other than itself, the thing understood is, so to speak, the father of the word conceived in the intellect, and the intellect itself resembles rather a mother, whose function is such that conception takes place in her. But when the intellect understands itself, the word conceived is related to the understanding person as offspring to father. Consequently, since we are using the term word in the latter sense (that is, according as God understands Himself), the word itself must be related to God, from whom the word proceeds, as Son to Father.

Generation in God Hence in the rule of the Catholic Faith we are taught to profess belief in the Father and Son in God by saying: "I believe in God the Father, and in His Son." And lest anyone, on hearing Father and Son mentioned, should have any notion of carnal generation, by which among us men father and son receive their designation,

John the Evangelist, to whom were revealed heavenly mysteries, By

Aquinas's Shorter Summa substitutes Word for Son," so that we may understand that the generation is intellectual.

The Son is equal to the Father in existence and essence Since natural existence and the action of understanding are distinct in us, we should note that a word conceived in our intellect, having only intellectual existence, differs in nature from our intellect, which has natural existence. In God, however, to be and to understand are identical. Therefore, the divine Word that is in God, whose Word He is according to intellectual existence, has the same existence as God, whose Word He is. Consequently the Word must be of the same essence and nature as God Himself, and all attributes whatsoever that are predicated of God, must pertain also to the Word of God.

This teaching in the Catholic Faith Hence we are instructed in the rule of the Catholic Faith to profess that the Son is "consubstantial with the Father," a phrase that excludes two errors. First, the Father and the Son may not be thought of according to carnal generation, which is effected by a certain separation of the son's substance from the father. If this were so in God, the Son could not be consubstantial with the Father.

Secondly, we are taught not to think of the Father and the Son according to intellectual generation in the way that a word is conceived in our mind. For such a word comes to our intellect by 44 John 1:14

The Holy Trinity a sort of accidental accretion, and does not exist with the existence proper to the essence of the intellect.

The Word is not distinct from the Father in time, species, or nature Among things that are not distinct in essence, there can be no distinction according to species, time, or nature. Therefore, since the Word is consubstantial with the Father, He cannot differ from the Father in any of these respects.

There can be no difference according to time. The divine Word is present in God for the reason that God understands Himself, thereby conceiving His intelligible Word. Hence, if at any time there were no Word of God, during that period God would not understand Himself. But God always understood Himself during His whole existence, because His understanding is His existence.

Therefore His Word, also, existed always. And so in the rule of the Catholic Faith we say that the Son of God "is born of the Father before all ages."

According to species, too, it is impossible for the Word of God to differ from God, as though He were inferior; for God does not understand Himself to be less than He is. The Word has a perfect likeness to the Father, because that whereof He is the Word is perfectly understood. Therefore the Word of God must be absolutely perfect according to the species of divinity.

Some beings, it is true, that proceed from others, are found not to inherit the perfect species of those from whom they proceed.

One way in which this can happen is in equivocal generations: the sun does not generate a sun, but an animal of some kind." In order

45 Ancient and medieval philosophers commonly admitted the possibility of "equivocal generation," according to which some organisms were thought

Aquinas's Shorter Summa to exclude imperfection of this sort from divine generation, we proclaim that the Word is born "God from God."

The same thing occurs in another way when that which proceeds from another differs from the latter because of a defect in purity; that is, when something is produced from what is simple and pure in itself by being applied to extraneous matter, and so turns out to be inferior to the original species. Thus, from a house that is in the architect's mind, a house is fashioned in various materials; and from light received in the surface of a body, color results; and from fire, by adding other elements, a mixture is produced; and from a beam of light, by interposing an opaque body, shadow is caused. To exclude any imperfection of this kind from divine generation, we add: "Light from Light."

In yet a third way, what proceeds from another can fail to equal the latter's species, because of a deficiency in truth. That is, it does not truly receive the nature of its original, but only a certain likeness thereof (for example, an image in a mirror or in a picture or ina statue; also, the likeness of a thing in the intellect or in one of the senses). For the image of a man is not said to be a true man, but is a likeness of a man; and a stone is not in the soul, as the Philosopher notes, but a likeness of the stone is in the soul.** To to be produced from inorganic matter, especially such as had previously been alive, under the influence of heavenly bodies, which were believed to be of a superior nature. Thus St. Thomas, Summa, Ia, q. 71, a. un.: "In the natural generation of animals begotten of seed, the active principle is the formative power that is in the seed; but in animals generated from putrefaction, the formative power is the influence of a heavenly body"; Ia., q. 91, a.2 ad 2: "The power of a heavenly body may cooperate in the work of natural generation, as the Philosopher says: 'Man is begotten from matter by man, and by the sun as well' (Aristotle, Phys., II, 2 [194 b 131]).

. But the power of the heavenly bodies suffices for the generation of certain imperfect animals from properly disposed matter."

46 Aristotle, De anima, III, 8 (431 b 29).

The Holy Trinity exclude all this from divine generation, we subjoin: "True God from true God."

Lastly it is impossible for the Word to differ from God according to nature, since it is natural for God to understand Himself.

Every intellect has some objects which it naturally understands.

Thus, our intellect naturally understands first principles. Much more does God, whose intellectual activity is His existence, naturally understand Himself.

Therefore His Word proceeds from Him naturally, not in the way that things proceed otherwise than by natural origin (that is, not in the way that artificial objects, which we are said to make, take shape from us). On the other hand, whatever proceeds from us naturally we are said to generate (for example, a son). Accordingly, to preclude the error of thinking that the Word of God proceeds from God, not by way of nature, but by the power of His will, the phrase is added: "begotten, not made."

Conclusion from the foregoing As is clear from the foregoing, all the characteristics of divine generation we have been discussing lead to the conclusion that the Son is consubstantial with the Father. Therefore, by way of summing up all these points, the words, "consubstantial with the Father," are subjoined.

~ God in Himself as beloved in lover As the object known is in the knower to the extent that it is known, so the beloved must be in the lover, as loved. The lover is, in some way, moved by the beloved with a certain interior impulse.

Aquinas's Shorter Summa Therefore, since a mover is in contact with the object moved, the beloved must be intrinsic to the lover. But God, just as He understands Himself, must likewise love Himself; for good, as apprehended, is in itself lovable. Consequently God is in Himself as beloved in lover.

Love in God as Spirit Since the object known is in the knower and the beloved is in the lover, the different ways of existing in something must be considered in the two cases before us. The act of understanding takes place by a certain assimilation of the knower to the object known; and so the object known must be in the knower in the sense that a likeness of it is present in him.

But the act of loving takes place through a sort of impulse engendered in the lover by the beloved: the beloved draws the lover to himself. Accordingly, the act of loving reaches its perfection not in a likeness of the beloved (in the way that the act of understanding reaches perfection in a likeness of the object understood); rather the act of loving reaches its perfection in a drawing of the lover to the beloved in person.

The transferring of the likeness of the original is effected by univocal generation whereby, among living beings, the begetter is called father, and the begotten is called son. Among such beings, moreover, the first motion occurs conformably to the species.

Therefore, as within the Godhead the way whereby God is in God as the known in the knower, is expressed by what we call Son, who is the Word of God, so the way by which God is in God as the beloved is in the lover is brought out by acknowledging in God a Spirit, who is the love of God. And so, according to the rule of the Catholic Faith, we are directed to believe in the Spirit.

The Holy Trinity

Holiness of the Spirit in God Another point to consider is this. Since good that is loved has the nature of an end, and since the motion of the will is designated good or evil in terms of the end it pursues, the love whereby the supreme good that is God is loved must possess the supereminent goodness that goes by the name of holiness. This is true whether holy is taken as equivalent to "pure," according to the Greeks (the idea being that in God there is purest goodness free from all defect) or whether holy is taken to mean "firm," in the view of the Latins

(on the score that in God there is unchangeable goodness). In either case, everything dedicated to God is called holy, such as a temple and the vessels of the temple and all objects consecrated to divine service. Rightly, then, the Spirit, who represents to us the love whereby God loves Himself, is called the Holy Spirit. For this reason the rule of the Catholic Faith proclaims that the Spirit is holy, in the clause, "I believe in the Holy Spirit."

Love in God is not accidental Just as God's understanding is His existence, so likewise is His love.

Accordingly, God does not love Himself by any act that is over and above His essence; He loves Himself by His very essence. Since

God loves Himself because He is in Himself as the beloved in the lover, God the beloved is not in God the lover in any accidental fashion (in the way that the objects of our love are in us who love them — that is, accidentally). No, God is substantially in Himself as beloved in lover. Therefore the Holy Spirit, who represents the divine love to us, is not something accidental in God, but subsists in the divine essence just as the Father and the Son do. And so in

Aquinas's Shorter Summa the rule of the Catholic Faith He is exhibited as no less worthy of adoration and glorification than the Father and the Son are.

Procession of the Holy Spirit from the Father and the Son We should recall that the act of understanding proceeds from the intellectual power of the mind. When the intellect actually understands, the object it understands is in it. The presence of the object known in the knower results from the intellectual power of the mind, and is its word, as we said above.*' Likewise, what is loved is in the lover, when it is actually loved. The fact that an object is actually loved, results from the lover's power to love and also from the lovable good as actually known. Accordingly, the presence of the beloved object in the lover is brought about by two factors: the appetitive principle and the intelligible object as apprehended

(that is, the word conceived about the lovable object). Therefore, since the Word in God who knows and loves Himself is the Son, and since He to whom the Word belongs is the Father of the Word, as is clear from our exposition, the necessary consequence is that the Holy Spirit, who pertains to the love whereby God is in Himself as beloved in lover, proceeds from the Father and the Son. And so we say in the Creed: "who proceeds from the Father and the Son."

The Trinity of divine persons and the unity of the divine essence We must conclude from all we have said that in the Godhead there is something threefold which is not opposed to the unity and 47 C£. chap. 37.

The Holy Trinity simplicity of the divine essence. We must acknowledge that God is, as existing in His nature, and that He is known and loved by Himself.

But this occurs otherwise in God than in us. Man, to be sure, is a substance in his nature; but his actions of knowing and loving are not his substance. Considered in his nature, man is indeed a subsisting thing; as he exists in his mind, however, he is not a subsisting thing, but a certain representation of a subsisting thing; and similarly with regard to his existence in himself as beloved in lover. Thus man may be regarded under three aspects: that is, man existing in his nature, man existing in his intellect, and man existing in his love. Yet these three are not one, for man's knowing is not his existing, and the same is true of his loving. Only one of these three is a subsisting thing, namely, man existing in his nature.

In God, on the contrary, to be, to know, and to love are identical. Therefore God existing in His natural being and God existing in the divine intellect and God existing in the divine love are one thing. Yet each of them is subsistent. And, as things subsisting in intellectual nature are usually called persons in Latin, or hypostases in Greek, the Latins say that there are three persons in God, and the Greeks say that there are three hypostases, namely, the Father, the Son, and the Holy Spirit.

5] A seeming contradiction in the Trinity A certain contradiction, arising from truths previously established, seemingly appears at this point. If threefold personality is assumed in God, then, since number always follows division, some division will have to be acknowledged in God whereby the three may be distinguished from one another. Thus supreme simplicity will be

Aquinas's Shorter Summa lacking in God. If three agree in some respect and differ in another, composition must be present — which is contrary to what was set forth above.*® Again, if God must be strictly one, as has been shown above," and if one and the same thing cannot originate or proceed from itself, it therefore seems impossible for God to be begotten or to proceed. Wrongly, therefore, the names of Father,

Son, and proceeding Spirit are given place in the Godhead.

Dz Solution of the difficulty: distinction in God according to relations The principle for solving this difficulty must be derived from the fact that, among different classes of beings, the various ways in which one thing may arise or proceed from another depend on the diversity of their natures. Among lifeless beings, which do not move themselves and are capable of being moved only from outside, one thing arises from another by being, as it were, outwardly altered and changed. In this way fire is generated from fire and air from air.

But among living beings (which have the property of moving themselves), something is generated within the parent (for example, the young of animals and the fruits of plants). Moreover, the different manner of procession in living beings must be viewed according to their different powers and their different kinds of proceeding.

Among such beings, there are certain powers whose operations extend only to bodies, so far as they are material. This is clear with regard to the powers of the vegetative soul, which serve nutrition, growth, and generation. In virtue of this class of the soul's powers,

48 C£. chap. 9.

49 Cf chap. 15.

The Holy Trinity there proceeds only what is corporeal and what is bodily distinct although, in the case of living beings, it is somehow joined to that from which it proceeds.

There are other powers whose operations do not transcend the limits of bodies and yet extend to the species of bodies, receiving them without their accompanying matter. This is the case with all the powers of the sensitive soul. For sense is capable of receiving species without matter, as the Philosopher says.'' But such faculties, although they are receptive of the forms of things in a sort of immaterial way, do not receive them without a bodily organ. If procession takes place within these powers of the soul, that which proceeds will not be something corporeal, nor will it be distinct or joined to that faculty whence it proceeds in a corporeal way, but rather in a certain incorporeal and immaterial fashion, although not entirely without the help of a bodily organ.

Thus the representations of things imagined, which exist in the imagination not as a body in a body, but in a certain spiritual way, proceed in animals. This is why imaginary vision is called spiritual by Augustine."

But if something proceeds in a way that is not corporeal when the imagination is in action, this will be the case much more in the operation of the intellectual faculty, which can act without any bodily organ at all; its operation is strictly immaterial. For in intellectual operation a word proceeds in such a way that it exists in the very intellect of the speaker, not as though contained therein locally, nor as bodily separated therefrom, but as present there in a manner that is conformable to its origin. The same is true in that procession which is observed to take place in the operation of the will, so far as the thing loved exists in the lover,

50 Aristotle, De anima, III, 4 (429 b 21).

51 De Genesi ad litteram, XII, vii, 16; xxiv, 50 (PL, XXXIV, 459, 474).

Aquinas's Shorter Summa in the sense described above." However, although the intellectual and sensitive powers are nobler in their own scale of being than the powers of the vegetative soul, nothing that subsists in the nature of the same species proceeds either in men or in other animals according to the procession of the imaginative or sensitive faculties. This occurs only in that procession which takes place through the operation of the vegetative soul.

The reason for this is that in all beings composed of matter and form, the multiplication of individuals in the same species is effected by a division of matter. Hence among men and other animals, composed as they are of form and matter, individuals are multiplied in the same species by the bodily division which ensues in the procession that is proper to the operation of the vegetative soul, but that does not take place in other operations of the soul.

In beings that are not composed of matter and form, no distinction can be discerned other than that of the forms themselves. But if the form, which is the reason for the distinction, is the substance of a thing, the distinction must obtain between subsistent things.

Of course, this is not the case if the form in question is not the substance of the thing.

As is clear from our discussion, every intellect has this in common, that what is conceived in the intellect must in some way proceed from the knower, so far as he is knowing; and in its procession it is to some extent distinct from him, just as the conception of the intellect, which is the intellectual likeness," is

52 CF. chap. 46.

°3 The term here used by St. Thomas, intentio intellecta, cannot well be translated literally. For our purposes we may translate it as "intellectual likeness," as "intellectual representation," or as "mental word." Regardless, the meaning itself is clear, for St. Thomas defines the term in his Summa

Contra Gentiles, IV, 11: "Dico autem intentionem intellectam id quod intellectus in seipso concipit de re intellecta" ; that is: "By intentio intellecta

The Holy Trinity distinct from the knowing intellect. Similarly the affection of the lover, whereby the beloved is in the lover, must proceed from the will of the lover so far as he is loving. But the divine intellect has this exclusive perfection: since God's understanding is His existence, His intellectual conception, which is the intelligible likeness, must be His substance; and the case is similar with affection in God, regarded as loving. Consequently the representation of the divine intellect, which is God's Word, is distinct from Him who produces the Word, not with respect to substantial existence, but only according to the procession of one from the other. And in God considered as loving, the same is true of the affection of love, which pertains to the Spirit.

Thus it is plain that nothing prevents God's Word, who is the Son, from being one with the Father in substance, and that, nevertheless, the Word is distinct from the Father according to the relation of procession, as we have said. Hence it is also evident that the same thing does not arise or proceed from itself; for the Son, as proceeding from the Father, is distinct from Him. And the same observation holds true of the Holy Spirit, relative to the Father and the Son.

D3 Nature of the relations whereby the Father, the Son, and the Holy Spirit are distinguished The relations by which the Father, the Son, and the Holy Spirit are distinguished from one another are real relations, and not merely mental relations. Those relations are purely mental which do not correspond to anything found in the nature of things, but I mean that which the intellect conceives within itself of the thing understood."

Aquinas's Shorter Summa depend on intellectual apprehension alone. Thus right and left in a stone are not real relations, but only mental relations; they do not correspond to any real disposition present in the stone, but exist only in the mind of one who apprehends the stone as left, because it is, for instance, to the left of some animal. On the other hand, left and right in an animal are real relations, because they correspond to certain dispositions found in definite parts of the animal. Therefore, since the relations which distinguish the Father, the Son, and the Holy Spirit really exist in God, the relations in question must be real relations, and are not merely mental relations.

Relations in God are not accidental These relations cannot inhere in God accidentally, because the operations on which the relations follow directly are the very substance of God, and also because, as was shown above," there can be no accident in God. Hence, if the relations are really in God, they cannot be accidentally inherent, but must be subsistent.

How it is that what is an accident in other things, can exist substantially in God, is clear from the doctrine previously set forth." a8) Personal distinction in God through the relations

Since distinction in the Godhead is accounted for by relations that are not accidental but are subsistent, and since among beings

°4 Cf. chap. 23.

> Cf. e.g., chaps. 4, 6, 9-11, 21.

The Holy Trinity subsisting in an intellectual nature personal distinction is discerned, it necessarily follows that personal distinction in God is constituted by the relations in question. Therefore the Father and the Son and the Holy Spirit are three persons, and also three hypostases, since hypostasis means "that which is subsistent and complete."

Impossibility of more than three persons in God There cannot be more than three persons in God. For the divine persons cannot be multiplied by a division of their substance, but solely by the relation of some procession; and not by any sort of procession, but only by such as does not have its term in something outside of God. If the relation had something external as its term, this would not possess the divine nature, and so could not be a divine person or hypostasis. But procession in God that does not terminate outside of God, must be either according to the operation of the intellect, whereby the Word proceeds, or according to the operation of the will, whereby love proceeds, as is clear from our exposition."® Therefore no divine person can proceed unless

He proceeds as the Word, whom we call the Son, or as love, whom we call the Holy Spirit.

Moreover, since God comprehends everything in His intellect by a single act of intuition and similarly loves everything by a single act of His will, there cannot be several words or several loves in God. If, then, the Son proceeds as Word, and if the Holy Spirit proceeds as love, there cannot be several Sons or several Holy

Spirits in God.

56 Cf chaps. 37, 46.

Aquinas's Shorter Summa Again: the perfect is that beyond which there is nothing.

Hence a being that would tolerate anything of its own class to be outside itself, would fall short of absolute perfection. This is why things that are simply perfect in their natures are not numerically multiplied; thus God, the sun, the moon, and so on.' But both the Son and the Holy Spirit must be simply perfect, since each of them is God, as we have shown."° Therefore several Sons or several Holy

Spirits are impossible.

Besides, that whereby a subsistent thing is this particular thing, distinct from other things, cannot be numerically multiplied, for the reason that an individual cannot be predicated of many. But the Son is this divine person, subsisting in Himself and distinct from the other divine persons by sonship just as Socrates is constituted this human person by individuating principles. Accordingly, as the individuating principles whereby Socrates is this man cannot pertain to more than one man, so sonship in the Godhead cannot pertain to more than one divine person. Similar is the case with the relation of the Father and the Holy Spirit. Hence there cannot be several Fathers in God or several Sons or several Holy

Spirits.

Lastly, whatever is one by reason of its form, is not numerically multiplied except through matter (thus, whiteness is multiplied by existing in many subjects). But there is no matter in God. Consequently, whatever is one in species and form in the Godhead cannot be multiplied numerically. Such are paternity and filiation

>? St. Thomas and the Scholastics of his time thought that the stars were incorruptible and were constructed of matter essentially different from the matter of terrestrial bodies. Consequently the sun, the moon, and all the stars were held to be superior to the material objects of our Earth.

°8 Cf. chap. 50. on

The Holy Trinity and the procession of the Holy Spirit. And thus there cannot be several Fathers or Sons or Holy Spirits in God.

Dy] Properties of the Father Such being the number of persons in God, the properties whereby the persons are distinguished from one another must be of some definite number. Three properties are characteristic of the Father.

The first is that whereby He is distinguished from the Son alone.

This is paternity. The second is that whereby the Father is distinguished from the other two persons, namely, the Son and the Holy

Spirit. And this is innascibility; for the Father is not God as proceeding from another person, whereas the Son and the Holy

Spirit do proceed from another person. The third property is that whereby the Father along with the Son is distinguished from the Holy Spirit. This is called their common spiration. But a property whereby the Father may be distinguished from the Holy Spirit alone is not to be assigned, for the reason that the Father and the Son are a single principle of the Holy Spirit, as has been shown."

Properties of the Son and the Holy Spirit Two properties must pertain to the Son: one whereby He is distinguished from the Father, and this is filiation; another whereby, along with the Father, He is distinguished from the Holy Spirit; and this is their common spiration. But no property is to be assigned whereby the Son is distinguished from the Holy Spirit alone,

59 Cf. chap. 49.

Aquinas's Shorter Summa because, as we said above, the Son and the Father are a single principle of the Holy Spirit. Similarly, no single property is to be assigned whereby the Holy Spirit and the Son together are distinguished from the Father. For the Father is distinguished from them by one property, namely, innascibility, inasmuch as He does not proceed. However, since the Son and the Holy Spirit proceed, not by one procession, but by several, they are distinguished from the Father by two properties. The Holy Spirit has only one property by which He is distinguished from the Father and the Son, and this is called procession. That there cannot be any property by which the Holy Spirit may be distinguished from the Son alone or from the Father alone, is evident from this whole discussion.

Accordingly, five properties in all are attributed to the divine persons: innascibility, paternity, filiation, spiration, and procession.

M Why these properties are called notions These five properties can be called notions of the persons, for the reason that the distinction between the persons in God is brought to our notice through them. On the other hand, they cannot be called properties, if the root meaning of property is insisted on, so that property is taken to mean a characteristic pertaining to one individual alone, for common spiration pertains to the Father and the Son.

But if the word property is employed in the sense of an attribute that is proper to some individuals as setting them off from others

(in the way that two-footed, for example, is proper to man and bird in contradistinction to quadrupeds), there is nothing to prevent

69 Cf. chap. 49.

The Holy Trinity even common spiration from being called a property. Since, however, the persons in God are distinguished solely by relations, and distinction among the divine persons is manifested by the notions, the notions must in some sense pertain to relationship.

But only four of the notions are real relations, whereby the divine persons are related to one another. The fifth notion, innascibility, pertains to relation as being the denial of relation (for negations are reduced to the genus of affirmations, and privations are reduced to the genus of habits, as, for example, not man is reduced to the genus of man, and not white is reduced to the genus of whiteness).°!

We should note that among the relations whereby the divine persons are related to one another, some have definite names, such as paternity and filiation, which properly signify relationship. But others lack a definite name: those whereby the Father and the Son are related to the Holy Spirit, and the Holy Spirit is related to them. So for these we use names of origin in place of relative names.

We perceive clearly that common spiration and procession signify origin, but not relations that follow origin. This can be brought out in the case of the relations between the Father and the Son. Generation denotes active origin, and is followed by the relation of paternity; and nativity signifies the passive generation of the Son, and is followed by the relation of filiation. In like manner, some relation follows common spiration, and the same is true of procession. But as these relations lack definite names, we use the names of the actions instead of relative names.

61 Tn connection with these two examples, see the better statement in the Summa, la, q. 33, a. 4 ad 3: "Negation is reduced to the genus of affirmation, just as not man is reduced to the genus of substance, and not white to the genus of quality."

Aquinas's Shorter Summa

The number of relations and the number of persons We must realize that, although the relations subsisting in the Godhead are the divine persons themselves, as was shown above," we are not therefore to conclude that there are five or four persons corresponding to the number of relations. For number follows distinction of some sort. Just as unity is indivisible or undivided, so plurality is divisible or divided. For a plurality of persons requires that relations have power to distinguish by reason of opposition, since formal distinction necessarily entails opposition. If, then, the relations in question are closely examined, paternity and filiation will be seen to have relative opposition to each other; hence they are incompatible in the same suppositum. Consequently paternity and filiation in God must be two subsistent persons. Innascibility, on the other hand, although opposed to filiation, is not opposed to paternity. Hence paternity and innascibility can pertain to one and the same person. Similarly, common spiration is not opposed either to paternity or to filiation, nor to innascibility. Thus nothing prevents common spiration from being in both the person of the Father and the person of the Son.

So common spiration is not a subsisting person distinct from the persons of the Father and the Son. But procession has a relation of opposition to common spiration. Therefore, since common spiration pertains to the Father and the Son, procession must be a person distinct from the persons of the Father and the Son.

Accordingly, the reason is clear why God is not called quiune (quinus) on account of the notions, which are five in number, but is called triune, on account of the Trinity of persons. The five

6 Cf. chaps. 54, 55.

The Holy Trinity notions are not five subsisting things, but the three persons are three subsisting things.

Although several notions or properties may pertain to a single person, only one of them constitutes the person. For a divine person is constituted by the properties, not in the sense that He is constituted by several of them, but in the sense that the relative, subsisting property itself is a person. If several properties were understood as subsisting in themselves apart, they would be several persons, and not one person. Hence we must understand that, of the several properties or notions belonging to a single person, the one that precedes™ according to the order of nature constitutes the person; the others are understood as inhering in the person already constituted.

Thus it is evident that innascibility cannot be the first notion of the Father, constituting His person, because nothing is constituted by a negation, and also because affirmation naturally precedes negation. Further, common spiration presupposes paternity and filiation in the order of nature, just as the procession of love presupposes the procession of the Word.

Hence common spiration cannot be the first notion of the Father or of the Son either. The first notion of the Father is paternity and the first notion of the Son is filiation, whereas procession alone is the notion of the Holy Spirit.

Accordingly, the notions constituting persons are three in number: paternity, filiation, and procession. And these notions must be strict properties. For that which constitutes a person must pertain to that person alone; individuating principles cannot belong to several individuals. Therefore, the three notions in question are called personal properties, in the sense that they constitute

63 The context requires the reading praecedit instead of procedit (which is found in the Vivés and the Mandonnet editions).

Aquinas's Shorter Summa the three persons in the manner described. The remaining notions are called properties or notions of the persons, but not personal properties or notions, since they do not constitute a person.

Dependence of the hypostases on the personal properties This makes it clear that if we were to remove the personal properties by intellectual abstraction, the hypostases could not remain. If a form is removed by intellectual abstraction, the subject of the form remains. Thus if whiteness is removed, the surface remains; if the surface is removed, the substance remains; if the form of the substance is removed, prime matter remains. But if the subject is removed, nothing remains.

In the case of God, the personal properties are the subsisting persons themselves. They do not constitute the persons in the sense that they are added to preexisting supposita; for in the Godhead nothing predicated absolutely, but only what is relative, can be distinct. So if the personal properties are removed by intellectual abstraction, no distinct hypostases remain. But if nonpersonal notions are thus removed, distinct hypostases do remain.

Effect of intellectual removal of personal properties If the question were to be asked whether, in consequence of the removal of the personal properties by intellectual abstraction, the divine essence would remain, the answer is that in one respect it would remain, but in another it would not. Intellectual abstraction can take place in two ways. The first is by abstracting form from matter. In this abstraction the mind proceeds from the more formal to the more material; the first subject remains until the end, and

The Holy Trinity the ultimate form is removed first. The second way of abstracting is by the abstraction of the universal from the particular, and this proceeds according to an order that is, in a sense, the opposite; the individuating material conditions are first removed, so that what is common may be retained.

In God, of course, there are neither matter and form, nor universal and particular. Nevertheless there is in the Godhead something that is common, and something that is proper and that supposes the common nature. In our human way of thinking, the divine persons are to the divine essence what individual supposita are toa common nature. According to the first type of intellectual abstraction, therefore, if we remove the personal properties, which are the subsisting persons themselves, the common nature does not remain. But in the second type of abstraction it does remain.

Personal acts and personal properties We can perceive from this discussion the nature of the order between the personal acts and the personal properties. The personal properties are subsistent persons. But a person subsisting in any nature whatsoever, acts in virtue of his nature when he communicates his nature; for the form of a species is the principle for generating a product that is of like species. Consequently, since personal acts in God have to do with communicating the divine nature, a subsisting person must communicate the common nature in virtue of the nature itself.

Two conclusions follow from this. The first is, that the generative power of the Father is the divine nature itself; for the power of performing any action is the principle in virtue of which a thing acts. The second conclusion is that, according to our way of conceiving, the personal act of generation presupposes both the

Aquinas's Shorter Summa divine nature and the personal property of the Father, which is the very hypostasis of the Father. This is true even though such property, regarded as a relation, follows from the act. Thus, in speaking of the Father, if we attend to the fact that He is a subsistent person, we can say that He generates because He is the Father. But if we are thinking of what pertains to relationship, it seems we should say, contrariwise, that He is the Father because He generates.

Generation with respect to the Father and with respect to the Son However, we should see that the order of active generation (with reference to paternity) is to be taken one way and the order of passive generation or nativity (with reference to filiation) is to be taken another. In the order of nature, active generation presupposes the person of the begetter. But in the same order, passive generation, or nativity, precedes the begotten person, for the begotten person owes his existence to his birth. Thus active generation, according to our way of representing it, presupposes paternity, understood as constituting the person of the Father. Nativity, however, does not presuppose filiation, understood as constituting the person of the Son but, according to our manner of conceiving, precedes it in both respects, that is, both as being constitutive of the person and as being a relation. And whatever pertains to the procession of the Holy Spirit is to be understood in a similar way.

Nature of the distinction between notional acts and notional properties In thus indicating the order between notional acts and notional properties, we do not mean to imply that notional acts differ from personal properties in objective reality: they are distinct only

The Holy Trinity according to our manner of conceiving. Just as God's act of understanding is God Himself understanding, so the Father's act of begetting is the begetting Father, although the modes of signifying are different. Likewise, although one divine person may have several notions, there is no composition in Him. Innascibility cannot cause any composition, since it isa negative property. And the two relations in the person of the Father (paternity and common spiration) are in reality identical as referring to the person of the Father; for, as the paternity is the Father, so common spiration in the Father is the Father, and in the Son is the Son. But these two properties differ according to the terms to which they refer; for by paternity the Father is related to the Son, and by common spiration He is related to the Holy Spirit. Likewise, the Son is related to the Father by filiation and to the Holy Spirit by common spiration.

Identity between the relative properties and the divine essence The relative properties must be the divine essence itself. For the relative properties are precisely the subsistent persons. But a person subsisting in the Godhead cannot be something other than the divine essence; and the divine essence is God Himself, as was shown above." Therefore the relative properties are in all reality identical with the divine essence.

Moreover, whatever is in a being besides its essence, is in it accidentally. But there cannot be any accidents in God, as was pointed out above.® Accordingly, the relative properties are not really distinct from the divine essence.

64 CF. chap. 10.

6 Cf. chap. 23.

Aquinas's Shorter Summa

The divine properties are not externally affixed The view proposed by Gilbert de la Porrée™ and some of his followers, that the properties under discussion are not in the persons, but are external to them, cannot be defended. Real relations must be in the things that are related. This is evident in the case of creatures, for real relations are in them as accidents in their subjects. But the relations whereby the three persons are distinguished within the Godhead are real relations, as was demonstrated above.*" Hence they must be in the divine persons, but not, of course, as accidents. Other perfections, too, which in creatures are accidents, cease to be accidents when transferred to God, as was shown above. Such are wisdom, justice, and the like.

Besides, there can be no distinction in God except through the relations; all perfections that are predicated absolutely are common. Therefore, if the relations were external to the persons, no distinction would remain among the persons themselves. And so there are relative properties in the persons; but they are the persons themselves, and also the divine essence itself. In the same way wisdom and goodness are said to be in God, and are God

Himself, as well as the divine essence, as was said above."

66 See Gilbert's commentaries, In librum de Trinitate (PL, LXIV, 1292) and In librum de praedicatione trium personarum (PL, LXIV, 1309). Gilbert retracted his error at the Council of Reims in 1148, as St. Bernard relates,

In Cantica, serm. LXXX (PL, CLXXXII]I, 1170). Cf. Denz., 389, 391.

6" Cf. chap. 53.

68 CF. chap. 23.

69 CE. chaps. 10, 22.

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