First, indeed, because man is directed to God, as to an end that surpasses the grasp of his reason: The eye hath not seen, O God, besides Thee, what things Thou hast prepared for them that love Thee (Isa 64:4). But the end must first be known by men who are to direct their thoughts and actions to the end. Hence it was necessary for the salvation of man that certain truths which exceed human reason should be made known to him by divine revelation.

Even as regards those truths about God which human reason could have discovered, it was necessary that man should be taught by a divine revelation; because the truth about God such as reason could discover, would only be known by a few, and that after a long time, and with the admixture of many errors. Whereas man’s whole salvation, which is in God, depends upon the knowledge of this truth. Therefore, in order that the salvation of men might be brought about more fitly and more surely, it was necessary that they should be taught divine truths by divine revelation.

It was therefore necessary that besides philosophical science built up by reason, there should be a sacred science learned through revelation.

So it is that sacred doctrine is a science because it proceeds from principles established by the light of a higher science, namely, the science of God and the blessed. Hence, just as the musician accepts on authority the principles taught him by the mathematician, so sacred science is established on principles revealed by God.

Still, it is more speculative than practical because it is more concerned with divine things than with human acts; though it does treat even of these latter, inasmuch as man is ordained by them to the perfect knowledge of God in which consists eternal bliss.

This is a sufficient answer to the Objections.

Now one speculative science is said to be nobler than another, either by reason of its greater certitude, or by reason of the higher worth of its subject-matter. In both these respects this science surpasses other speculative sciences. It surpasses them as regards greater certitude because other sciences derive their certitude from the natural light of human reason, which can err; whereas this derives its certitude from the light of divine knowledge, which cannot be misled. It surpasses them as regards the higher worth of its subject-matter because this science treats chiefly of those things which by their sublimity transcend human reason; while other sciences consider only those things which are within reason’s grasp.

Of the practical sciences, that one is nobler which is ordained to a further purpose, as political science is nobler than military science; for the good of the army is directed to the good of the State. But the purpose of this science, in so far as it is practical, is eternal bliss; to which as to an ultimate end the purposes of every practical science are directed.

Hence it is clear that from every standpoint, it is nobler than other sciences.

For since it is the part of a wise man to arrange and to judge, and since lesser matters should be judged in the light of some higher principle, he is said to be wise in any one order who considers the highest principle in that order: thus in the order of building, he who plans the form of the house is called wise and architect, in opposition to the inferior laborers who trim the wood and make ready the stones: As a wise architect, I have laid the foundation (1 Cor 3:10). Again, in the order of all human life, the prudent man is called wise, inasmuch as he directs his acts to a fitting end: Wisdom is prudence to a man (Prov 10: 23). Therefore he who considers absolutely the highest cause of the whole universe, namely God, is most of all called wise. Hence wisdom is said to be the knowledge of divine things, as Augustine says (De Trin. xii, 14).

But sacred doctrine essentially treats of God viewed as the highest cause—not only so far as He can be known through creatures just as philosophers knew Him—That which is known of God is manifest in them (Rom 1:19)—but also as far as He is known to Himself alone and revealed to others. Hence sacred doctrine is especially called wisdom.

Some, however, looking to what is treated of in this science, and not to the aspect under which it is treated, have asserted the object of this science to be something other than God—that is, either things and signs; or the works of salvation; or the whole Christ, as the head and members. Of all these things, in truth, we treat in this science, but so far as they have reference to God.

However, it is to be borne in mind, in regard to the philosophical sciences, that the inferior sciences neither prove their principles nor dispute with those who deny them, but leave this to a higher science; whereas the highest of them, viz. metaphysics, can dispute with one who denies its principles, if only the opponent will make some concession; but if he concede nothing, it can have no dispute with him, though it can answer his objections.

Hence Sacred Scripture, since it has no science above itself, can dispute with one who denies its principles only if the opponent admits some at least of the truths obtained through divine revelation; thus we can argue with heretics from texts in Holy Writ, and against those who deny one article of faith, we can argue from another. If our opponent believes nothing of divine revelation, there is no longer any means of proving the articles of faith by reasoning, but only of answering his objections—if he has any—against faith. Since faith rests upon infallible truth, and since the contrary of a truth can never be demonstrated, it is clear that the arguments brought against faith cannot be demonstrations, but are difficulties that can be answered.

But sacred doctrine makes use even of human reason, not, indeed, to prove faith (for thereby the merit of faith would come to an end), but to make clear other things that are put forward in this doctrine. Since therefore grace does not destroy nature but perfects it, natural reason should minister to faith as the natural bent of the will ministers to charity. Hence the Apostle says: Bringing into captivity every understanding unto the obedience of Christ (2 Cor 10:5). Hence sacred doctrine makes use also of the authority of philosophers in those questions in which they were able to know the truth by natural reason, as Paul quotes a saying of Aratus: As some also of your own poets said: For we are also His offspring (Acts 17:28). Nevertheless, sacred doctrine makes use of these authorities as extrinsic and probable arguments; but properly uses the authority of the canonical Scriptures as an incontrovertible proof, and the authority of the doctors of the Church as one that may properly be used, yet merely as probable. For our faith rests upon the revelation made to the apostles and prophets who wrote the canonical books, and not on the revelations (if any such there are) made to other doctors. Hence Augustine says (Epis. ad Hieron. xix, 1): Only those books of Scripture which are called canonical have I learned to hold in such honor as to believe their authors have not erred in any way in writing them. But other authors I so read as not to deem everything in their works to be true, merely on account of their having so thought and written, whatever may have been their holiness and learning.

It is also befitting Holy Writ, which is proposed to all without distinction of persons—‘To the wise and to the unwise I am a debtor’ (Rom 1:14)—that spiritual truths be expounded by means of figures taken from corporeal things, in order that thereby even the simple who are unable by themselves to grasp intellectual things may be able to understand it.

Now this spiritual sense has a threefold division. For as the Apostle says (Heb 10:1), the Old Law is a figure of the New Law, and Dionysius says (Coel. Hier. i) the New Law itself is a figure of future glory. Again, in the New Law, whatever our Head has done is a type of what we ought to do. Therefore, so far as the things of the Old Law signify the things of the New Law, there is the allegorical sense; so far as the things done in Christ, or so far as the things which signify Christ, are types of what we ought to do, there is the moral sense. But so far as they signify what relates to eternal glory, there is the anagogical sense. Since the literal sense is that which the author intends, and since the author of Holy Writ is God, Who by one act comprehends all things by His intellect, it is not unfitting, as Augustine says (Confess. xii), if, even according to the literal sense, one word in Holy Writ should have several senses.

Therefore I say that this proposition, God exists, of itself is self-evident, for the predicate is the same as the subject, because God is His own existence as will be hereafter shown (Q. 3, Art. 4). Now because we do not know the essence of God, the proposition is not self-evident to us; but needs to be demonstrated by things that are more known to us, though less known in their nature—namely, by effects.

The first and more manifest way is the argument from motion. It is certain, and evident to our senses, that in the world some things are in motion. Now whatever is in motion is put in motion by another, for nothing can be in motion except as it is in potentiality to that towards which it is in motion; whereas a thing moves inasmuch as it is in act. For motion is nothing else than the reduction of something from potentiality to actuality. But nothing can be reduced from potentiality to actuality, except by something in a state of actuality. Thus that which is actually hot, as fire, makes wood, which is potentially hot, to be actually hot, and thereby moves and changes it. Now it is not possible that the same thing should be at once in actuality and potentiality in the same respect, but only in different respects. For what is actually hot cannot simultaneously be potentially hot; but it is simultaneously potentially cold. It is therefore impossible that in the same respect and in the same way a thing should be both mover and moved, i.e., that it should move itself. Therefore, whatever is in motion must be put in motion by another.

If that by which it is put in motion be itself put in motion, then this also must needs be put in motion by another, and that by another again. But this cannot go on to infinity, because then there would be no first mover, and, consequently, no other mover; seeing that subsequent movers move only inasmuch as they are put in motion by the first mover; as the staff moves only because it is put in motion by the hand.

Therefore it is necessary to arrive at a first mover, put in motion by no other; and this everyone understands to be God.

The second way is from the nature of the efficient cause. In the world of sense we find there is an order of efficient causes. There is no case known (neither is it, indeed, possible) in which a thing is found to be the efficient cause of itself; for so it would be prior to itself, which is impossible.

Now in efficient causes it is not possible to go on to infinity, because in all efficient causes following in order, the first is the cause of the intermediate cause, and the intermediate is the cause of the ultimate cause, whether the intermediate cause be several, or only one. Now to take away the cause is to take away the effect. Therefore, if there be no first cause among efficient causes, there will be no ultimate, nor any intermediate cause. But if in efficient causes it is possible to go on to infinity, there will be no first efficient cause, neither will there be an ultimate effect, nor any intermediate efficient causes; all of which is plainly false.

Therefore it is necessary to admit a first efficient cause, to which everyone gives the name of God.

The third way is taken from possibility and necessity, and runs thus. We find in nature things that are possible to be and not to be, since they are found to be generated, and to corrupt, and consequently, they are possible to be and not to be.

But it is impossible for these always to exist, for that which is possible not to be at some time is not. Therefore, if everything is possible not to be, then at one time there could have been nothing in existence. Now if this were true, even now there would be nothing in existence, because that which does not exist only begins to exist by something already existing. Therefore, if at one time nothing was in existence, it would have been impossible for anything to have begun to exist; and thus even now nothing would be in existence—which is absurd. Therefore, not all beings are merely possible, but there must exist something the existence of which is necessary.

But every necessary thing either has its necessity caused by another, or not. Now it is impossible to go on to infinity in necessary things which have their necessity caused by another, as has been already proved in regard to efficient causes.

Therefore we cannot but postulate the existence of some being having of itself its own necessity, and not receiving it from another, but rather causing in others their necessity. This all men speak of as God.

The fourth way is taken from the gradation to be found in things. Among beings there are some more and some less good, true, noble and the like. But more and less are predicated of different things, according as they resemble in their different ways something which is the maximum, as a thing is said to be hotter according as it more nearly resembles that which is hottest; so that there is something which is truest, something best, something noblest and, consequently, something which is uttermost being; for those things that are greatest in truth are greatest in being, as it is written in Metaph. ii.

Now the maximum in any genus is the cause of all in that genus; as fire, which is the maximum heat, is the cause of all hot things.

Therefore there must also be something which is to all beings the cause of their being, goodness, and every other perfection; and this we call God.

The fifth way is taken from the governance of the world. We see that things which lack intelligence, such as natural bodies, act for an end, and this is evident from their acting always, or nearly always, in the same way, so as to obtain the best result. Hence it is plain that not fortuitously, but designedly, do they achieve their end.

Now whatever lacks intelligence cannot move towards an end, unless it be directed by some being endowed with knowledge and intelligence; as the arrow is shot to its mark by the archer.

Therefore some intelligent being exists by whom all natural things are directed to their end; and this being we call God.

First, because no body moves unless it is put in motion, as is evident from induction. Now it has been already proved (Q. 2, A. 3) that God is the First Mover, and is Himself unmoved. Therefore it is clear that God is not a body.

Second, because the first being must of necessity be in act, and in no way in potentiality. For although in any single thing that passes from potentiality to actuality, the potentiality is prior in time to the actuality; nevertheless, absolutely speaking, actuality is prior to potentiality; for whatever is in potentiality can be reduced into actuality only by some being in actuality. Now it has been already proved that God is the First Being. It is therefore impossible that in God there should be any potentiality. But every body is in potentiality because the continuous, as such, is divisible to infinity; it is therefore impossible that God should be a body.

Third, because God is the most noble of beings. Now it is impossible for a body to be the most noble of beings; for a body must be either animate or inanimate; and an animate body is manifestly nobler than any inanimate body. But an animate body is not animate precisely as body; otherwise all bodies would be animate. Therefore its animation depends upon some other thing, as our body depends for its animation on the soul. Hence that by which a body becomes animated must be nobler than the body. Therefore it is impossible that God should be a body.

Or, as says Dionysius (Div. Nom. ix), by the depth of God is meant the incomprehensibility of His essence; by length, the procession of His all-pervading power; by breadth, His overspreading all things, inasmuch as all things lie under His protection.

First, because matter is in potentiality. But we have shown (Q. 2, A. 3) that God is pure act, without any potentiality. Hence it is impossible that God should be composed of matter and form.

Second, because everything composed of matter and form owes its perfection and goodness to its form; therefore its goodness is participated, inasmuch as matter participates the form. Now the first good and the best—viz. God—is not a participated good, because the essential good is prior to the participated good. Hence it is impossible that God should be composed of matter and form.

Third, because every agent acts by its form; hence the manner in which it has its form is the manner in which it is an agent. Therefore whatever is primarily and essentially an agent must be primarily and essentially form. Now God is the first agent, since He is the first efficient cause. He is therefore of His essence a form; and not composed of matter and form.

On the other hand, in things not composed of matter and form, in which individualization is not due to individual matter—that is to say, to this matter—the very forms being individualized of themselves—it is necessary the forms themselves should be subsisting supposita. Therefore suppositum and nature in them are identified. Since God then is not composed of matter and form, He must be His own Godhead, His own Life, and whatever else is thus predicated of Him.

First, whatever a thing has besides its essence must be caused either by the constituent principles of that essence (like a property that necessarily accompanies the species—as the faculty of laughing is proper to a man—and is caused by the constituent principles of the species), or by some exterior agent—as heat is caused in water by fire. Therefore, if the existence of a thing differs from its essence, this existence must be caused either by some exterior agent or by its essential principles. Now it is impossible for a thing’s existence to be caused by its essential constituent principles, for nothing can be the sufficient cause of its own existence, if its existence is caused. Therefore that thing, whose existence differs from its essence, must have its existence caused by another. But this cannot be true of God; because we call God the first efficient cause. Therefore it is impossible that in God His existence should differ from His essence.

Second, existence is that which makes every form or nature actual; for goodness and humanity are spoken of as actual, only because they are spoken of as existing. Therefore existence must be compared to essence, if the latter is a distinct reality, as actuality to potentiality. Therefore, since in God there is no potentiality, as shown above (A. 1), it follows that in Him essence does not differ from existence. Therefore His essence is His existence.

Third, because, just as that which has fire, but is not itself fire, is on fire by participation; so that which has existence but is not existence, is a being by participation. But God is His own essence, as shown above (A. 3); if, therefore, He is not His own existence He will be not essential, but participated being. He will not therefore be the first being—which is absurd. Therefore God is His own existence, and not merely His own essence.

First, because a species is constituted of genus and difference. Now that from which the difference constituting the species is derived, is always related to that from which the genus is derived, as actuality is related to potentiality. For animal is derived from sensitive nature, by concretion as it were, for that is animal, which has a sensitive nature. Rational being, on the other hand, is derived from intellectual nature, because that is rational, which has an intellectual nature, and intelligence is compared to sense, as actuality is to potentiality. The same argument holds good in other things. Hence since in God actuality is not added to potentiality, it is impossible that He should be in any genus as a species.

Second, since the existence of God is His essence, if God were in any genus, He would be the genus being, because, since genus is predicated as an essential it refers to the essence of a thing. But the Philosopher has shown (Metaph. iii) that being cannot be a genus, for every genus has differences distinct from its generic essence. Now no difference can exist distinct from being; for non-being cannot be a difference. It follows then that God is not in a genus.

Third, because all in one genus agree in the quiddity or essence of the genus which is predicated of them as an essential, but they differ in their existence. For the existence of man and of horse is not the same; as also of this man and that man: thus in every member of a genus, existence and quiddity—i.e., essence—must differ. But in God they do not differ, as shown in the preceding article. Therefore it is plain that God is not in a genus as if He were a species.

From this it is also plain that He has no genus nor difference, nor can there be any definition of Him; nor, save through His effects, a demonstration of Him: for a definition is from genus and difference; and the mean of a demonstration is a definition.

That God is not in a genus, as reducible to it as its principle, is clear from this, that a principle reducible to any genus does not extend beyond that genus; as, a point is the principle of continuous quantity alone; and unity, of discontinuous quantity. But God is the principle of all being. Therefore He is not contained in any genus as its principle.

First, because a subject is compared to its accidents as potentiality to actuality; for a subject is in some sense made actual by its accidents. But there can be no potentiality in God, as was shown (Q. 2, A. 3).

Second, because God is His own existence; and as Boethius says (Hebdom.), although every essence may have something superadded to it, this cannot apply to absolute being: thus a heated substance can have something extraneous to heat added to it, as whiteness, nevertheless absolute heat can have nothing else than heat.

Third, because what is essential is prior to what is accidental. Whence as God is absolute primal being, there can be in Him nothing accidental. Neither can He have any essential accidents (as the capability of laughing is an essential accident of man), because such accidents are caused by the constituent principles of the subject. Now there can be nothing caused in God, since He is the first cause. Hence it follows that there is no accident in God.

First, from the previous articles of this question. For there is neither composition of quantitative parts in God, since He is not a body; nor composition of matter and form; nor does His nature differ from His suppositum; nor His essence from His existence; neither is there in Him composition of genus and difference, nor of subject and accident. Therefore, it is clear that God is nowise composite, but is altogether simple.

Second, because every composite is posterior to its component parts, and is dependent on them; but God is the first being, as shown above (Q. 2, A. 3).

Third, because every composite has a cause, for things in themselves different cannot unite unless something causes them to unite. But God is uncaused, as shown above (Q. 2, A. 3), since He is the first efficient cause.

Fourth, because in every composite there must be potentiality and actuality; but this does not apply to God; for either one of the parts actuates another, or at least all the parts are potential to the whole.

Fifth, because nothing composite can be predicated of any single one of its parts. And this is evident in a whole made up of dissimilar parts; for no part of a man is a man, nor any of the parts of the foot, a foot. But in wholes made up of similar parts, although something which is predicated of the whole may be predicated of a part (as a part of the air is air, and a part of water, water), nevertheless certain things are predicable of the whole which cannot be predicated of any of the parts; for instance, if the whole volume of water is two cubits, no part of it can be two cubits. Thus in every composite there is something which is not it itself. But, even if this could be said of whatever has a form, viz. that it has something which is not it itself, as in a white object there is something which does not belong to the essence of white; nevertheless in the form itself, there is nothing besides itself. And so, since God is absolute form, or rather absolute being, He can be in no way composite. Hilary implies this argument, when he says (De Trin. vii): God, Who is strength, is not made up of things that are weak; nor is He Who is light, composed of things that are dim.

Now all these contain manifest untruth; since it is not possible for God to enter into the composition of anything, either as a formal or a material principle. First, because God is the first efficient cause. Now the efficient cause is not identical numerically with the form of the thing caused, but only specifically: for man begets man. But primary matter can be neither numerically nor specifically identical with an efficient cause; for the former is merely potential, while the latter is actual.

Second, because, since God is the first efficient cause, to act belongs to Him primarily and essentially. But that which enters into composition with anything does not act primarily and essentially, but rather the composite so acts; for the hand does not act, but the man by his hand; and, fire warms by its heat. Hence God cannot be part of a compound.

Third, because no part of a compound can be absolutely primal among beings—not even matter, nor form, though they are the primal parts of every compound. For matter is merely potential; and potentiality is absolutely posterior to actuality, as is clear from the foregoing (Q. 3, A. 1): while a form which is part of a compound is a participated form; and as that which participates is posterior to that which is essential, so likewise is that which is participated; as fire in ignited objects is posterior to fire that is essentially such. Now it has been proved that God is absolutely primal being (Q. 2, A. 3).

Now God is the first principle, not material, but in the order of efficient cause, which must be most perfect. For just as matter, as such, is merely potential, an agent, as such, is in the state of actuality. Hence, the first active principle must needs be most actual, and therefore most perfect; for a thing is perfect in proportion to its state of actuality, because we call that perfect which lacks nothing of the mode of its perfection.

First, because whatever perfection exists in an effect must be found in the effective cause: either in the same formality, if it is a univocal agent—as when man reproduces man; or in a more eminent degree, if it is an equivocal agent—thus in the sun is the likeness of whatever is generated by the sun’s power. Now it is plain that the effect pre-exists virtually in the efficient cause: and although to pre-exist in the potentiality of a material cause is to pre-exist in a more imperfect way, since matter as such is imperfect, and an agent as such is perfect; still to pre-exist virtually in the efficient cause is to pre-exist not in a more imperfect, but in a more perfect way. Since therefore God is the first effective cause of things, the perfections of all things must pre-exist in God in a more eminent way. Dionysius implies the same line of argument by saying of God (Div. Nom. v): It is not that He is this and not that, but that He is all, as the cause of all.

Second, from what has been already proved, God is existence itself, of itself subsistent (Q. 3, A. 4). Consequently, He must contain within Himself the whole perfection of being. For it is clear that if some hot thing has not the whole perfection of heat, this is because heat is not participated in its full perfection; but if this heat were self-subsisting, nothing of the virtue of heat would be wanting to it. Since therefore God is subsisting being itself, nothing of the perfection of being can be wanting to Him. Now all created perfections are included in the perfection of being; for things are perfect, precisely so far as they have being after some fashion. It follows therefore that the perfection of no one thing is wanting to God. This line of argument, too, is implied by Dionysius (Div. Nom. v), when he says that, God exists not in any single mode, but embraces all being within Himself, absolutely, without limitation, uniformly; and afterwards he adds that, He is the very existence to subsisting things.

This suffices for the Reply to the Second Objection.

Some things are said to be like, which communicate in the same form according to the same formality, and according to the same mode; and these are said to be not merely like, but equal in their likeness; as two things equally white are said to be alike in whiteness; and this is the most perfect likeness.

In another way, we speak of things as alike which communicate in form according to the same formality, though not according to the same measure, but according to more or less, as something less white is said to be like another thing more white; and this is imperfect likeness.

In a third way some things are said to be alike which communicate in the same form, but not according to the same formality; as we see in non-univocal agents. For since every agent reproduces itself so far as it is an agent, and everything acts according to the manner of its form, the effect must in some way resemble the form of the agent.

If therefore the agent is contained in the same species as its effect, there will be a likeness in form between that which makes and that which is made, according to the same formality of the species; as man reproduces man. If, however, the agent and its effect are not contained in the same species, there will be a likeness, but not according to the formality of the same species; as things generated by the sun’s heat may be in some sort spoken of as like the sun, not as though they received the form of the sun in its specific likeness, but in its generic likeness. Therefore if there is an agent not contained in any genus, its effect will still more distantly reproduce the form of the agent, not, that is, so as to participate in the likeness of the agent’s form according to the same specific or generic formality, but only according to some sort of analogy; as existence is common to all. In this way all created things, so far as they are beings, are like God as the first and universal principle of all being.

But goodness signifies perfection which is desirable; and consequently of ultimate perfection. Hence that which has ultimate perfection is said to be simply good; but that which has not the ultimate perfection it ought to have (although, in so far as it is at all actual, it has some perfection), is not said to be perfect simply nor good simply, but only relatively. In this way, therefore, viewed in its primal (i.e., substantial) being a thing is said to be simply, and to be good relatively (i.e., in so far as it has being) but viewed in its complete actuality, a thing is said to be relatively, and to be good simply.

Hence the saying of Boethius (De Hebdom.), I perceive that in nature the fact that things are good is one thing; that they are is another, is to be referred to a thing’s goodness simply, and having being simply. Because, regarded in its primal actuality, a thing simply exists; and regarded in its complete actuality, it is good simply—in such sort that even in its primal actuality, it is in some sort good, and even in its complete actuality, it in some sort has being.

Again, according to the Platonists, who, through not distinguishing primary matter from privation, said that matter was non-being, goodness is more extensively participated than being; for primary matter participates in goodness as tending to it, for all seek their like; but it does not participate in being, since it is presumed to be non-being. Therefore Dionysius says that goodness extends to non-existence (Div. Nom. v).

Or it may be said that goodness extends to existing and non-existing things, not so far as it can be predicated of them, but so far as it can cause them—if, indeed, by non-existence we understand not simply those things which do not exist, but those which are potential, and not actual. For goodness has the aspect of the end, in which not only actual things find their completion, but also towards which tend even those things which are not actual, but merely potential. Now being implies the habitude of a formal cause only, either inherent or exemplar; and its causality does not extend save to those things which are actual.

Nevertheless, the idea of goodness presupposes the idea of an efficient cause, and also of a formal cause. For we see that what is first in causing, is last in the thing caused. Fire, e.g., heats first of all before it reproduces the form of fire; though the heat in the fire follows from its substantial form. Now in causing, goodness and the end come first, both of which move the agent to act; second, the action of the agent moving to the form; third, comes the form. Hence in that which is caused the converse ought to take place, so that there should be first, the form whereby it is a being; second, we consider in it its effective power, whereby it is perfect in being, for a thing is perfect when it can reproduce its like, as the Philosopher says (Meteor. iv); third, there follows the formality of goodness which is the basic principle of its perfection.

Now the form presupposes determination or commensuration of its principles, whether material or efficient, and this is signified by the mode: hence it is said that the measure marks the mode. But the form itself is signified by the species; for everything is placed in its species by its form. Hence the number is said to give the species, for definitions signifying species are like numbers, according to the Philosopher (Metaph. viii); for as a unit added to, or taken from a number, changes its species, so a difference added to, or taken from a definition, changes its species. Further, upon the form follows an inclination to the end, or to an action, or something of the sort; for everything, in so far as it is in act, acts and tends towards that which is in accordance with its form; and this belongs to weight and order. Hence the essence of goodness, so far as it consists in perfection, consists also in mode, species and order.

For everything is good so far as it is desirable, and is a term of the movement of the appetite; the term of whose movement can be seen from a consideration of the movement of a natural body. Now the movement of a natural body is terminated by the end absolutely; and relatively by the means through which it comes to the end, where the movement ceases; so a thing is called a term of movement, so far as it terminates any part of that movement. Now the ultimate term of movement can be taken in two ways, either as the thing itself towards which it tends, e.g., a place or form; or a state of rest in that thing.

Thus, in the movement of the appetite, the thing desired that terminates the movement of the appetite relatively, as a means by which something tends towards another, is called the useful; but that sought after as the last thing absolutely terminating the movement of the appetite, as a thing towards which for its own sake the appetite tends, is called the virtuous; for the virtuous is that which is desired for its own sake; but that which terminates the movement of the appetite in the form of rest in the thing desired, is called the pleasant.

This triple perfection belongs to no creature by its own essence; it belongs to God only, in Whom alone essence is existence; in Whom there are no accidents; since whatever belongs to others accidentally belongs to Him essentially; as, to be powerful, wise and the like, as appears from what is stated above (Q. 3, A. 6); and He is not directed to anything else as to an end, but is Himself the last end of all things. Hence it is manifest that God alone has every kind of perfection by His own essence; therefore He Himself alone is good essentially.

But as regards absolute things opinions differ. Plato held the existence of separate ideas (Q. 84, A. 4) of all things, and that individuals were denominated by them as participating in the separate ideas; for instance, that Socrates is called man according to the separate idea of man. Now just as he laid down separate ideas of man and horse which he called absolute man and absolute horse, so likewise he laid down separate ideas of being and of one, and these he called absolute being and absolute oneness; and by participation of these, everything was called being or one; and what was thus absolute being and absolute one, he said was the supreme good. And because good is convertible with being, as one is also, he called God the absolute good, from whom all things are called good by way of participation.

Although this opinion appears to be unreasonable in affirming separate ideas of natural things as subsisting of themselves—as Aristotle argues in many ways—still, it is absolutely true that there is first something which is essentially being and essentially good, which we call God, as appears from what is shown above (Q. 2, A. 3), and Aristotle agrees with this. Hence from the first being, essentially such, and good, everything can be called good and a being, inasmuch as it participates in it by way of a certain assimilation which is far removed and defective; as appears from the above (Q. 4, A. 3).

Everything is therefore called good from the divine goodness, as from the first exemplary effective and final principle of all goodness. Nevertheless, everything is called good by reason of the similitude of the divine goodness belonging to it, which is formally its own goodness, whereby it is denominated good. And so of all things there is one goodness, and yet many goodnesses.

This is a sufficient Reply to the Objections.

We must consider therefore that a thing is called infinite because it is not finite. Now matter is in a way made finite by form, and the form by matter. Matter indeed is made finite by form, inasmuch as matter, before it receives its form, is in potentiality to many forms; but on receiving a form, it is terminated by that one. Again, form is made finite by matter, inasmuch as form, considered in itself, is common to many; but when received in matter, the form is determined to this one particular thing.

Now matter is perfected by the form by which it is made finite; therefore infinite as attributed to matter, has the nature of something imperfect; for it is as it were formless matter. On the other hand, form is not made perfect by matter, but rather is contracted by matter; and hence the infinite, regarded on the part of the form not determined by matter, has the nature of something perfect.

Now being is the most formal of all things, as appears from what is shown above (Q. 4, A. 1, Obj. 3). Since therefore the divine being is not a being received in anything, but He is His own subsistent being as was shown above (Q. 3, A. 4), it is clear that God Himself is infinite and perfect.

From this appears the Reply to the First Objection.

For with regard to infinite as applied to matter, it is manifest that everything actually existing possesses a form; and thus its matter is determined by form. But because matter, considered as existing under some substantial form, remains in potentiality to many accidental forms, that which is absolutely finite can be relatively infinite; as, for example, wood is finite according to its own form, but still it is relatively infinite, inasmuch as it is in potentiality to an infinite number of shapes.

But if we speak of the infinite in reference to form, it is manifest that those things, the forms of which are in matter, are absolutely finite, and in no way infinite. If, however, any created forms are not received into matter, but are self-subsisting, as some think is the case with angels, these will be relatively infinite, inasmuch as such kinds of forms are not terminated, nor contracted by any matter. But because a created form thus subsisting has being, and yet is not its own being, it follows that its being is received and contracted to a determinate nature. Hence it cannot be absolutely infinite.

We must therefore observe that a body, which is a complete magnitude, can be considered in two ways; mathematically, in respect to its quantity only; and naturally, as regards its matter and form.

Now it is manifest that a natural body cannot be actually infinite. For every natural body has some determined substantial form. Since therefore the accidents follow upon the substantial form, it is necessary that determinate accidents should follow upon a determinate form; and among these accidents is quantity. So every natural body has a greater or smaller determinate quantity. Hence it is impossible for a natural body to be infinite.

The same appears from movement; because every natural body has some natural movement; whereas an infinite body could not have any natural movement; neither direct, because nothing moves naturally by a direct movement unless it is out of its place; and this could not happen to an infinite body, for it would occupy every place, and thus every place would be indifferently its own place. Neither could it move circularly; forasmuch as circular motion requires that one part of the body is necessarily transferred to a place occupied by another part, and this could not happen as regards an infinite circular body: for if two lines be drawn from the center, the farther they extend from the center, the farther they are from each other; therefore, if a body were infinite, the lines would be infinitely distant from each other; and thus one could never occupy the place belonging to any other.

The same applies to a mathematical body. For if we imagine a mathematical body actually existing, we must imagine it under some form, because nothing is actual except by its form; hence, since the form of quantity as such is figure, such a body must have some figure, and so would be finite; for figure is confined by a term or boundary.

Now this is impossible; because it would entail something dependent on an infinity for its existence; and hence its generation could never come to be, because it is impossible to pass through an infinite medium.

A multitude is said to be accidentally infinite when its existence as such is not necessary, but accidental. This can be shown, for example, in the work of a carpenter requiring a certain absolute multitude; namely, art in the soul, the movement of the hand, and a hammer; and supposing that such things were infinitely multiplied, the carpentering work would never be finished, forasmuch as it would depend on an infinite number of causes. But the multitude of hammers, inasmuch as one may be broken and another used, is an accidental multitude; for it happens by accident that many hammers are used, and it matters little whether one or two, or many are used, or an infinite number, if the work is carried on for an infinite time. In this way they said that there can be an accidentally infinite multitude.

This, however, is impossible; since every kind of multitude must belong to a species of multitude. Now the species of multitude are to be reckoned by the species of numbers. But no species of number is infinite; for every number is multitude measured by one. Hence it is impossible for there to be an actually infinite multitude, either absolute or accidental.

Likewise multitude in nature is created; and everything created is comprehended under some clear intention of the Creator; for no agent acts aimlessly. Hence everything created must be comprehended in a certain number. Therefore it is impossible for an actually infinite multitude to exist, even accidentally.

But a potentially infinite multitude is possible; because the increase of multitude follows upon the division of magnitude; since the more a thing is divided, the greater number of things result. Hence, as the infinite is to be found potentially in the division of the continuous, because we thus approach matter, as was shown in the preceding article, by the same rule, the infinite can be also found potentially in the addition of multitude.

But being is innermost in each thing and most fundamentally inherent in all things since it is formal in respect of everything found in a thing, as was shown above (Q. 7, A. 1). Hence it must be that God is in all things, and innermostly.

Now in both these senses, in some way God is in every place; and this is to be everywhere. First, as He is in all things giving them being, power and operation; so He is in every place as giving it existence and locative power. Again, things placed are in place, inasmuch as they fill place; and God fills every place; not, indeed, like a body, for a body is said to fill place inasmuch as it excludes the co-presence of another body; whereas by God being in a place, others are not thereby excluded from it; indeed, by the very fact that He gives being to the things that fill every place, He Himself fills every place.

This appears also in accidental forms which have accidental quantity; as an example, whiteness is whole in each part of the surface if we speak of its totality of essence; because according to the perfect idea of its species it is found to exist in every part of the surface. But if its totality be considered according to quantity which it has accidentally, then it is not whole in every part of the surface.

On the other hand, incorporeal substances have no totality either of themselves or accidentally, except in reference to the perfect idea of their essence. Hence, as the soul is whole in every part of the body, so is God whole in all things and in each one.

But how He is in other things created by Him, may be considered from human affairs. A king, for example, is said to be in the whole kingdom by his power, although he is not everywhere present. Again a thing is said to be by its presence in other things which are subject to its inspection; as things in a house are said to be present to anyone, who nevertheless may not be in substance in every part of the house. Lastly, a thing is said to be by way of substance or essence in that place in which its substance may be.

Now there were some (the Manichees) who said that spiritual and incorporeal things were subject to the divine power; but that visible and corporeal things were subject to the power of a contrary principle. Therefore against these it is necessary to say that God is in all things by His power.

But others, though they believed that all things were subject to the divine power, still did not allow that divine providence extended to these inferior bodies, and in the person of these it is said, He walketh about the poles of the heavens; and He doth not consider our things (Job 22:14). Against these it is necessary to say that God is in all things by His presence.

Further, others said that, although all things are subject to God’s providence, still all things are not immediately created by God; but that He immediately created the first creatures, and these created the others. Against these it is necessary to say that He is in all things by His essence.

Therefore, God is in all things by His power, inasmuch as all things are subject to His power; He is by His presence in all things, as all things are bare and open to His eyes; He is in all things by His essence, inasmuch as He is present to all as the cause of their being.

Now to be everywhere primarily is said of that which in its whole self is everywhere; for if a thing were everywhere according to its parts in different places, it would not be primarily everywhere, forasmuch as what belongs to anything according to part does not belong to it primarily; thus if a man has white teeth, whiteness belongs primarily not to the man but to his teeth.

But a thing is everywhere absolutely when it does not belong to it to be everywhere accidentally, that is, merely on some supposition; as a grain of millet would be everywhere, supposing that no other body existed. It belongs therefore to a thing to be everywhere absolutely when, on any supposition, it must be everywhere.

And this properly belongs to God alone. For whatever number of places be supposed, even if an infinite number be supposed besides what already exist, it would be necessary that God should be in all of them; for nothing can exist except by Him. Therefore to be everywhere primarily and absolutely belongs to God and is proper to Him: because whatever number of places be supposed to exist, God must be in all of them, not as to a part of Him, but as to His very self.

First, because it was shown above that there is some first being, whom we call God; and that this first being must be pure act, without the admixture of any potentiality, for the reason that, absolutely, potentiality is posterior to act. Now everything which is in any way changed, is in some way in potentiality. Hence it is evident that it is impossible for God to be in any way changeable.

Second, because everything which is moved, remains as it was in part, and passes away in part; as what is moved from whiteness to blackness, remains the same as to substance; thus in everything which is moved, there is some kind of composition to be found. But it has been shown above (Q. 3, A. 7) that in God there is no composition, for He is altogether simple. Hence it is manifest that God cannot be moved.

Third, because everything which is moved acquires something by its movement, and attains to what it had not attained previously. But since God is infinite, comprehending in Himself all the plenitude of perfection of all being, He cannot acquire anything new, nor extend Himself to anything whereto He was not extended previously. Hence movement in no way belongs to Him. So, some of the ancients, constrained, as it were, by the truth, decided that the first principle was immovable.

For all creatures before they existed, were possible, not by any created power, since no creature is eternal, but by the divine power alone, inasmuch as God could produce them into existence. Thus, as the production of a thing into existence depends on the will of God, so likewise it depends on His will that things should be preserved; for He does not preserve them otherwise than by ever giving them existence; hence if He took away His action from them, all things would be reduced to nothing, as appears from Augustine (Gen ad lit. iv, 12). Therefore as it was in the Creator’s power to produce them before they existed in themselves, so likewise it is in the Creator’s power when they exist in themselves to bring them to nothing. In this way therefore, by the power of another—namely, of God—they are mutable, inasmuch as they are producible from nothing by Him, and are by Him reducible from existence to non-existence.

If, however, a thing is called mutable by a power in itself, thus also in some manner every creature is mutable. For every creature has a twofold power, active and passive; and I call that power passive which enables anything to attain its perfection either in being, or in attaining to its end. Now if the mutability of a thing be considered according to its power for being, in that way all creatures are not mutable, but those only in which what is potential in them is consistent with non-being.

Hence, in the inferior bodies there is mutability both as regards substantial being, inasmuch as their matter can exist with privation of their substantial form, and also as regards their accidental being, supposing the subject to coexist with privation of accident; as, for example, this subject man can exist with not-whiteness and can therefore be changed from white to not-white. But supposing the accident to be such as to follow on the essential principles of the subject, then the privation of such an accident cannot coexist with the subject. Hence the subject cannot be changed as regards that kind of accident; as, for example, snow cannot be made black.

Now in the celestial bodies matter is not consistent with privation of form, because the form perfects the whole potentiality of the matter; therefore these bodies are not mutable as to substantial being, but only as to locality, because the subject is consistent with privation of this or that place.

On the other hand, incorporeal substances, being subsistent forms which, although with respect to their own existence are as potentiality to act, are not consistent with the privation of this act; forasmuch as existence is consequent upon form, and nothing corrupts except it lose its form. Hence in the form itself there is no power to non-existence; and so these kinds of substances are immutable and invariable as regards their existence. Wherefore Dionysius says (Div. Nom. iv) that intellectual created substances are pure from generation and from every variation, as also are incorporeal and immaterial substances. Still, there remains in them a twofold mutability: one as regards their potentiality to their end; and in that way there is in them a mutability according to choice from good to evil, as Damascene says (De Fide ii, 3,4); the other as regards place, inasmuch as by their finite power they attain to certain fresh places—which cannot be said of God, who by His infinity fills all places, as was shown above (Q. 8, A. 2).

Thus in every creature there is a potentiality to change either as regards substantial being as in the case of things corruptible; or as regards locality only, as in the case of the celestial bodies; or as regards the order to their end, and the application of their powers to diverse objects, as in the case with the angels; and universally all creatures generally are mutable by the power of the Creator, in Whose power is their existence and non-existence. Hence since God is in none of these ways mutable, it belongs to Him alone to be altogether immutable.

Further, those things are said to be measured by time which have a beginning and an end in time, because in everything which is moved there is a beginning, and there is an end. But as whatever is wholly immutable can have no succession, so it has no beginning, and no end.

Thus eternity is known from two sources: first, because what is eternal is interminable—that is, has no beginning nor end (that is, no term either way); second, because eternity has no succession, being simultaneously whole.

Or to reign beyond eternity can be taken to mean that if any other thing were conceived to exist for ever, as the movement of the heavens according to some philosophers, then God would still reign beyond, inasmuch as His reign is simultaneously whole.

Accordingly, however, as some receive immutability from Him, they share in His eternity. Thus some receive immutability from God in the way of never ceasing to exist; in that sense it is said of the earth, it standeth for ever (Eccl. 1:4). Again, some things are called eternal in Scripture because of the length of their duration, although they are in nature corruptible; thus (Ps 75:5) the hills are called eternal and we read of the fruits of the eternal hills. (Deut 33:15). Some again, share more fully than others in the nature of eternity, inasmuch as they possess unchangeableness either in being or further still in operation; like the angels, and the blessed, who enjoy the Word, because as regards that vision of the Word, no changing thoughts exist in the Saints, as Augustine says (De Trin. xv). Hence those who see God are said to have eternal life; according to that text, This is eternal life, that they may know Thee the only true God, etc. (John 17:3).

Supposing, however, that the aforesaid difference be considered on the part of the things measured, and not as regards the measures, then there is some reason for it, inasmuch as that alone is measured by time which has beginning and end in time. Hence, if the movement of the heavens lasted always, time would not be of its measure as regards the whole of its duration, since the infinite is not measurable; but it would be the measure of that part of its revolution which has beginning and end in time.

Another reason for the same can be taken from these measures in themselves, if we consider the end and the beginning as potentialities; because, granted also that time always goes on, yet it is possible to note in time both the beginning and the end, by considering its parts: thus we speak of the beginning and the end of a day or of a year; which cannot be applied to eternity. Still these differences follow upon the essential and primary differences, that eternity is simultaneously whole, but that time is not so.

Others assign the difference between these three to consist in the fact that eternity has no before and after; but that time has both, together with innovation and veteration; and that aeviternity has before and after without innovation and veteration. This theory, however, involves a contradiction; which manifestly appears if innovation and veteration be referred to the measure itself. For since before and after of duration cannot exist together, if aeviternity has before and after, it must follow that with the receding of the first part of aeviternity, the after part of aeviternity must newly appear; and thus innovation would occur in aeviternity itself, as it does in time. And if they be referred to the things measured, even then an incongruity would follow. For a thing which exists in time grows old with time, because it has a changeable existence, and from the changeableness of a thing measured, there follows before and after in the measure, as is clear from Physic. iv. Therefore the fact that an aeviternal thing is neither inveterate, nor subject to innovation, comes from its changelessness; and consequently its measure does not contain before and after.

We say then that since eternity is the measure of a permanent being, in so far as anything recedes from permanence of being, it recedes from eternity. Now some things recede from permanence of being, so that their being is subject to change, or consists in change; and these things are measured by time, as are all movements, and also the being of all things corruptible. But others recede less from permanence of being, forasmuch as their being neither consists in change, nor is the subject of change; nevertheless they have change annexed to them either actually or potentially. This appears in the heavenly bodies, the substantial being of which is unchangeable; and yet with unchangeable being they have changeableness of place. The same applies to the angels, who have an unchangeable being as regards their nature with changeableness as regards choice; moreover they have changeableness of intelligence, of affections and of places in their own degree. Therefore these are measured by aeviternity which is a mean between eternity and time. But the being that is measured by eternity is not changeable, nor is it annexed to change. In this way time has before and after; aeviternity in itself has no before and after, which can, however, be annexed to it; while eternity has neither before nor after, nor is it compatible with such at all.

Now some say that there is only one time for temporal things, forasmuch as one number exists for all things numbered; as time is a number, according to the Philosopher (Physic. iv). This, however, is not a sufficient reason; because time is not a number abstracted from the thing numbered, but existing in the thing numbered; otherwise it would not be continuous; for ten ells of cloth are continuous not by reason of the number, but by reason of the thing numbered. Now number as it exists in the thing numbered, is not the same for all; but it is different for different things.

Hence, others assert that the unity of eternity as the principle of all duration is the cause of the unity of time. Thus all durations are one in that view, in the light of their principle, but are many in the light of the diversity of things receiving duration from the influx of the first principle. On the other hand others assign primary matter as the cause why time is one; as it is the first subject of movement, the measure of which is time. Neither of these reasons, however, is sufficient; forasmuch as things which are one in principle, or in subject, especially if distant, are not one absolutely, but accidentally.

Therefore the true reason why time is one, is to be found in the oneness of the first movement by which, since it is most simple, all other movements are measured (Metaph. X). Therefore time is referred to that movement, not only as a measure is to the thing measured, but also as accident is to subject; and thus receives unity from it. Whereas to other movements it is compared only as the measure is to the thing measured. Hence it is not multiplied by their multitude, because by one separate measure many things can be measured.

This being established, we must observe that a twofold opinion existed concerning spiritual substances. Some said that all proceeded from God in a certain equality, as Origen said (Peri Archon. i); or at least many of them, as some others thought. Others said that all spiritual substances proceeded from God in a certain degree and order; and Dionysius (Coel. Hier. x) seems to have thought so, when he said that among spiritual substances there are the first, the middle and the last; even in one order of angels. Now according to the first opinion, it must be said that there are many aeviternities as there are many aeviternal things of first degree. But according to the second opinion, it would be necessary to say that there is one aeviternity only; because since each thing is measured by the most simple element of its genus, it must be that the existence of all aeviternal things should be measured by the existence of the first aeviternal thing, which is all the more simple the nearer it is to the first. Wherefore because the second opinion is truer, as will be shown later (Q. 47, A. 2); we concede at present that there is only one aeviternity.

Pythagoras and Plato, seeing that the one convertible with being did not add any reality to being, but signified the substance of being as undivided, thought that the same applied to the one which is the principle of number. And because number is composed of unities, they thought that numbers were the substances of all things.

Avicenna, however, on the contrary, considering that one which is the principle of number, added a reality to the substance of being (otherwise number made of unities would not be a species of quantity), thought that the one convertible with being added a reality to the substance of beings; as white to man. This, however, is manifestly false, inasmuch as each thing is one by its substance. For if a thing were one by anything else but by its substance, since this again would be one, supposing it were again one by another thing, we should be driven on to infinity.

Hence we must adhere to the former statement; therefore we must say that the one which is convertible with being, does not add a reality to being; but that the one which is the principle of number, does add a reality to being, belonging to the genus of quantity.

On the other hand, if it be undivided accidentally, and divided absolutely, as if it were divided in essence and undivided in idea or in principle or cause, it will be many absolutely and one accidentally; as what are many in number and one in species or one in principle. Hence in that way, being is divided by one and by many; as it were by one absolutely and by many accidentally. For multitude itself would not be contained under being, unless it were in some way contained under one. Thus Dionysius says (Div. Nom., cap. ult.) that there is no kind of multitude that is not in a way one. But what are many in their parts, are one in their whole; and what are many in accidents, are one in subject; and what are many in number, are one in species; and what are many in species, are one in genus; and what are many in processions, are one in principle.

First from His simplicity. For it is manifest that the reason why any singular thing is this particular thing is because it cannot be communicated to many: since that whereby Socrates is a man, can be communicated to many; whereas, what makes him this particular man, is only communicable to one. Therefore, if Socrates were a man by what makes him to be this particular man, as there cannot be many Socrates, so there could not in that way be many men. Now this belongs to God alone; for God Himself is His own nature, as was shown above (Q. 3, A. 3). Therefore, in the very same way God is God, and He is this God. Impossible is it therefore that many Gods should exist.

Second, this is proved from the infinity of His perfection. For it was shown above (Q. 4, A. 2) that God comprehends in Himself the whole perfection of being. If then many gods existed, they would necessarily differ from each other. Something therefore would belong to one which did not belong to another. And if this were a privation, one of them would not be absolutely perfect; but if a perfection, one of them would be without it. So it is impossible for many gods to exist. Hence also the ancient philosophers, constrained as it were by truth, when they asserted an infinite principle, asserted likewise that there was only one such principle.

Third, this is shown from the unity of the world. For all things that exist are seen to be ordered to each other since some serve others. But things that are diverse do not harmonize in the same order, unless they are ordered thereto by one. For many are reduced into one order by one better than by many: because one is the per se cause of one, and many are only the accidental cause of one, inasmuch as they are in some way one. Since therefore what is first is most perfect, and is so per se and not accidentally, it must be that the first which reduces all into one order should be only one. And this one is God.

But what is supremely knowable in itself, may not be knowable to a particular intellect, on account of the excess of the intelligible object above the intellect; as, for example, the sun, which is supremely visible, cannot be seen by the bat by reason of its excess of light.

Therefore some who considered this, held that no created intellect can see the essence of God. This opinion, however, is not tenable. For as the ultimate beatitude of man consists in the use of his highest function, which is the operation of his intellect; if we suppose that the created intellect could never see God, it would either never attain to beatitude, or its beatitude would consist in something else beside God; which is opposed to faith. For the ultimate perfection of the rational creature is to be found in that which is the principle of its being; since a thing is perfect so far as it attains to its principle. Further the same opinion is also against reason. For there resides in every man a natural desire to know the cause of any effect which he sees; and thence arises wonder in men. But if the intellect of the rational creature could not reach so far as to the first cause of things, the natural desire would remain void.

Hence it must be absolutely granted that the blessed see the essence of God.

But if the principle of the visual power and the thing seen were one and the same thing, it would necessarily follow that the seer would receive both the visual power and the form whereby it sees, from that one same thing. Now it is manifest both that God is the author of the intellectual power, and that He can be seen by the intellect. And since the intellective power of the creature is not the essence of God, it follows that it is some kind of participated likeness of Him who is the first intellect.

Hence also the intellectual power of the creature is called an intelligible light, as it were, derived from the first light, whether this be understood of the natural power, or of some perfection superadded of grace or of glory. Therefore, in order to see God, there must be some similitude of God on the part of the visual faculty, whereby the intellect is made capable of seeing God.

But on the part of the object seen, which must necessarily be united to the seer, the essence of God cannot be seen by any created similitude. First, because as Dionysius says (Div. Nom. i), by the similitudes of the inferior order of things, the superior can in no way be known; as by the likeness of a body the essence of an incorporeal thing cannot be known. Much less therefore can the essence of God be seen by any created likeness whatever.

Second, because the essence of God is His own very existence, as was shown above (Q. 3, A. 4), which cannot be said of any created form; and so no created form can be the similitude representing the essence of God to the seer.

Third, because the divine essence is uncircumscribed, and contains in itself super-eminently whatever can be signified or understood by the created intellect. Now this cannot in any way be represented by any created likeness; for every created form is determined according to some aspect of wisdom, or of power, or of being itself, or of some like thing. Hence to say that God is seen by some similitude, is to say that the divine essence is not seen at all; which is false.

Therefore it must be said that to see the essence of God, there is required some similitude in the visual faculty, namely, the light of glory strengthening the intellect to see God, which is spoken of in the Psalm (35:10), In Thy light we shall see light. The essence of God, however, cannot be seen by any created similitude representing the divine essence itself as it really is.

Now the mode of being of things is manifold. For some things have being only in this one individual matter; as all bodies. But others are subsisting natures, not residing in matter at all, which, however, are not their own existence, but receive it; and these are the incorporeal beings, called angels.

But to God alone does it belong to be His own subsistent being. Therefore what exists only in individual matter we know naturally, forasmuch as our soul, whereby we know, is the form of certain matter. Now our soul possesses two cognitive powers; one is the act of a corporeal organ, which naturally knows things existing in individual matter; hence sense knows only the singular. But there is another kind of cognitive power in the soul, called the intellect; and this is not the act of any corporeal organ. Wherefore the intellect naturally knows natures which exist only in individual matter; not as they are in such individual matter, but according as they are abstracted therefrom by the considering act of the intellect; hence it follows that through the intellect we can understand these objects as universal; and this is beyond the power of the sense.

Now the angelic intellect naturally knows natures that are not in matter; but this is beyond the power of the intellect of our soul in the state of its present life, united as it is to the body. It follows therefore that to know self-subsistent being is natural to the divine intellect alone; and this is beyond the natural power of any created intellect; for no creature is its own existence, forasmuch as its existence is participated. Therefore the created intellect cannot see the essence of God, unless God by His grace unites Himself to the created intellect, as an object made intelligible to it.

Now since the natural power of the created intellect does not avail to enable it to see the essence of God, as was shown in the preceding article, it is necessary that the power of understanding should be added by divine grace. Now this increase of the intellectual powers is called the illumination of the intellect, as we also call the intelligible object itself by the name of light of illumination. And this is the light spoken of in the Apocalypse (Rev 21:23): The glory of God hath enlightened it—viz. the society of the blessed who see God. By this light the blessed are made deiform—i.e., like to God, according to the saying: When He shall appear we shall be like to Him, and we shall see Him as He is (1 John 3:2).

Hence the intellect which has more of the light of glory will see God the more perfectly; and he will have a fuller participation of the light of glory who has more charity; because where there is the greater charity, there is the more desire; and desire in a certain degree makes the one desiring apt and prepared to receive the object desired. Hence he who possesses the more charity, will see God the more perfectly, and will be the more beatified.

Thus appears the answer to the Second Objection. For when it is said that one intellect does not understand one and the same thing better than another, this would be true if referred to the mode of the thing understood, for whoever understands it otherwise than it really is, does not truly understand it, but not if referred to the mode of understanding, for the understanding of one is more perfect than the understanding of another.

In proof of this we must consider that what is comprehended is perfectly known; and that is perfectly known which is known so far as it can be known. Thus, if anything which is capable of scientific demonstration is held only by an opinion resting on a probable proof, it is not comprehended; as, for instance, if anyone knows by scientific demonstration that a triangle has three angles equal to two right angles, he comprehends that truth; whereas if anyone accepts it as a probable opinion because wise men or most men teach it, he cannot be said to comprehend the thing itself, because he does not attain to that perfect mode of knowledge of which it is intrinsically capable.

But no created intellect can attain to that perfect mode of the knowledge of the Divine intellect whereof it is intrinsically capable. Which thus appears—Everything is knowable according to its actuality. But God, whose being is infinite, as was shown above (Q. 7), is infinitely knowable. Now no created intellect can know God infinitely. For the created intellect knows the Divine essence more or less perfectly in proportion as it receives a greater or lesser light of glory. Since therefore the created light of glory received into any created intellect cannot be infinite, it is clearly impossible for any created intellect to know God in an infinite degree. Hence it is impossible that it should comprehend God.

But in another sense comprehension is taken more largely as opposed to non-attainment; for he who attains to anyone is said to comprehend him when he attains to him. And in this sense God is comprehended by the blessed, according to the words, I held him, and I will not let him go (Cant. 3:4); in this sense also are to be understood the words quoted from the Apostle concerning comprehension. And in this way comprehension is one of the three prerogatives of the soul, responding to hope, as vision responds to faith, and fruition responds to charity. For even among ourselves not everything seen is held or possessed, forasmuch as things either appear sometimes afar off, or they are not in our power of attainment. Neither, again, do we always enjoy what we possess; either because we find no pleasure in them, or because such things are not the ultimate end of our desire, so as to satisfy and quell it. But the blessed possess these three things in God; because they see Him, and in seeing Him, possess Him as present, having the power to see Him always; and possessing Him, they enjoy Him as the ultimate fulfilment of desire.

This can be seen in the fact that the more our soul is abstracted from corporeal things, the more it is capable of receiving abstract intelligible things. Hence in dreams and alienations of the bodily senses divine revelations and foresight of future events are perceived the more clearly. It is not possible, therefore, that the soul in this mortal life should be raised up to the supreme of intelligible objects, i.e., to the divine essence.

Hence we know that His relationship with creatures so far as to be the cause of them all; also that creatures differ from Him, inasmuch as He is not in any way part of what is caused by Him; and that creatures are not removed from Him by reason of any defect on His part, but because He superexceeds them all.

Now in both of these, human knowledge is assisted by the revelation of grace. For the intellect’s natural light is strengthened by the infusion of gratuitous light; and sometimes also the images in the human imagination are divinely formed, so as to express divine things better than those do which we receive from sensible objects, as appears in prophetic visions; while sometimes sensible things, or even voices, are divinely formed to express some divine meaning; as in the Baptism, the Holy Spirit was seen in the shape of a dove, and the voice of the Father was heard, This is My beloved Son (Matt 3:17).

But demonstrative pronouns are applied to God as describing what is understood, not what is sensed. For we can only describe Him as far as we understand Him. Thus, according as nouns, participles and demonstrative pronouns are applicable to God, so far can He be signified by relative pronouns.

But as regards absolute and affirmative names of God, as good, wise, and the like, various and many opinions have been given. For some have said that all such names, although they are applied to God affirmatively, nevertheless have been brought into use more to express some remotion from God, rather than to express anything that exists positively in Him. Hence they assert that when we say that God lives, we mean that God is not like an inanimate thing; and the same in like manner applies to other names; and this was taught by Rabbi Moses. Others say that these names applied to God signify His relationship towards creatures: thus in the words, God is good, we mean, God is the cause of goodness in things; and the same rule applies to other names.

Both of these opinions, however, seem to be untrue for three reasons. First because in neither of them can a reason be assigned why some names more than others are applied to God. For He is assuredly the cause of bodies in the same way as He is the cause of good things; therefore if the words God is good, signified no more than, God is the cause of good things, it might in like manner be said that God is a body, inasmuch as He is the cause of bodies. So also to say that He is a body implies that He is not a mere potentiality, as is primary matter.

Second, because it would follow that all names applied to God would be said of Him by way of being taken in a secondary sense, as healthy is secondarily said of medicine, forasmuch as it signifies only the cause of the health in the animal which primarily is called healthy.

Third, because this is against the intention of those who speak of God. For in saying that God lives, they assuredly mean more than to say that He is the cause of our life, or that He differs from inanimate bodies.

Therefore we must hold a different doctrine—viz. that these names signify the divine substance, and are predicated substantially of God, although they fall short of a full representation of Him. Which is proved thus. For these names express God, so far as our intellects know Him. Now since our intellect knows God from creatures, it knows Him as far as creatures represent Him. Now it is shown above (Q. 4, A. 2) that God prepossesses in Himself all the perfections of creatures, being Himself simply and universally perfect. Hence every creature represents Him, and is like Him so far as it possesses some perfection; yet it represents Him not as something of the same species or genus, but as the excelling principle of whose form the effects fall short, although they derive some kind of likeness thereto, even as the forms of inferior bodies represent the power of the sun. This was explained above (Q. 4, A. 3), in treating of the divine perfection.

Therefore the aforesaid names signify the divine substance, but in an imperfect manner, even as creatures represent it imperfectly. So when we say, God is good, the meaning is not, God is the cause of goodness, or God is not evil; but the meaning is, Whatever good we attribute to creatures, pre-exists in God, and in a more excellent and higher way. Hence it does not follow that God is good, because He causes goodness; but rather, on the contrary, He causes goodness in things because He is good; according to what Augustine says (De Doctr. Christ. i, 32), Because He is good, we are.

But even according to what was said above (A. 2), that these names signify the divine substance, although in an imperfect manner, it is also clear from what has been said (AA. 1, 2) that they have diverse meanings. For the idea signified by the name is the conception in the intellect of the thing signified by the name. But our intellect, since it knows God from creatures, in order to understand God, forms conceptions proportional to the perfections flowing from God to creatures, which perfections pre-exist in God unitedly and simply, whereas in creatures they are received and divided and multiplied. As therefore, to the different perfections of creatures, there corresponds one simple principle represented by different perfections of creatures in a various and manifold manner, so also to the various and multiplied conceptions of our intellect, there corresponds one altogether simple principle, according to these conceptions, imperfectly understood. Therefore although the names applied to God signify one thing, still because they signify that under many and different aspects, they are not synonymous.

Thus appears the solution of the First Objection, since synonymous terms signify one thing under one aspect; for words which signify different aspects of one thing, do not signify primarily and absolutely one thing; because the term only signifies the thing through the medium of the intellectual conception, as was said above.

Neither, on the other hand, are names applied to God and creatures in a purely equivocal sense, as some have said. Because if that were so, it follows that from creatures nothing could be known or demonstrated about God at all; for the reasoning would always be exposed to the fallacy of equivocation. Such a view is against the philosophers, who proved many things about God, and also against what the Apostle says: The invisible things of God are clearly seen being understood by the things that are made (Rom 1:20). Therefore it must be said that these names are said of God and creatures in an analogous sense, i.e., according to proportion.

Now names are thus used in two ways: either according as many things are proportionate to one, thus for example healthy predicated of medicine and urine in relation and in proportion to health of a body, of which the latter is the sign and the former the cause: or according as one thing is proportionate to another, thus healthy is said of medicine and animal, since medicine is the cause of health in the animal body.

And in this way some things are said of God and creatures analogically, and not in a purely equivocal nor in a purely univocal sense. For we can name God only from creatures (A. 1). Thus whatever is said of God and creatures, is said according to the relation of a creature to God as its principle and cause, wherein all perfections of things pre-exist excellently. Now this mode of community of idea is a mean between pure equivocation and simple univocation. For in analogies the idea is not, as it is in univocals, one and the same, yet it is not totally diverse as in equivocals; but a term which is thus used in a multiple sense signifies various proportions to some one thing; thus healthy applied to urine signifies the sign of animal health, and applied to medicine signifies the cause of the same health.

The arguments adduced in the contrary sense prove indeed that these names are not predicated univocally of God and creatures; yet they do not prove that they are predicated equivocally.

Thus all names applied metaphorically to God, are applied to creatures primarily rather than to God, because when said of God they mean only similitudes to such creatures. For as smiling applied to a field means only that the field in the beauty of its flowering is like the beauty of the human smile by proportionate likeness, so the name of lion applied to God means only that God manifests strength in His works, as a lion in his. Thus it is clear that applied to God the signification of names can be defined only from what is said of creatures.

But to other names not applied to God in a metaphorical sense, the same rule would apply if they were spoken of God as the cause only, as some have supposed. For when it is said, God is good, it would then only mean God is the cause of the creature’s goodness; thus the term good applied to God would include in its meaning the creature’s goodness. Hence good would apply primarily to creatures rather than to God.

But as was shown above (A. 2), these names are applied to God not as the cause only, but also essentially. For the words, God is good, or wise, signify not only that He is the cause of wisdom or goodness, but that these exist in Him in a more excellent way. Hence as regards what the name signifies, these names are applied primarily to God rather than to creatures, because these perfections flow from God to creatures; but as regards the imposition of the names, they are primarily applied by us to creatures which we know first. Hence they have a mode of signification which belongs to creatures, as said above (A. 3).

Sometimes from both extremes it is an idea only, as when mutual order or habitude can only go between things in the apprehension of reason; as when we say a thing is the same as itself. For reason apprehending one thing twice regards it as two; thus it apprehends a certain habitude of a thing to itself. And the same applies to relations between being and non-being formed by reason, apprehending non-being as an extreme. The same is true of relations that follow upon an act of reason, as genus and species, and the like.

Now there are other relations which are realities as regards both extremes, as when for instance a habitude exists between two things according to some reality that belongs to both; as is clear of all relations, consequent upon quantity; as great and small, double and half, and the like; for quantity exists in both extremes: and the same applies to relations consequent upon action and passion, as motive power and the movable thing, father and son, and the like.

Again, sometimes a relation in one extreme may be a reality, while in the other extreme it is an idea only; and this happens whenever two extremes are not of one order; as sense and science refer respectively to sensible things and to intellectual things; which, inasmuch as they are realities existing in nature, are outside the order of sensible and intellectual existence. Therefore in science and in sense a real relation exists, because they are ordered either to the knowledge or to the sensible perception of things; whereas the things looked at in themselves are outside this order, and hence in them there is no real relation to science and sense, but only in idea, inasmuch as the intellect apprehends them as terms of the relations of science and sense. Hence the Philosopher says (Metaph. v) that they are called relative, not forasmuch as they are related to other things, but as others are related to them. Likewise for instance, on the right is not applied to a column, unless it stands as regards an animal on the right side; which relation is not really in the column, but in the animal.

Since therefore God is outside the whole order of creation, and all creatures are ordered to Him, and not conversely, it is manifest that creatures are really related to God Himself; whereas in God there is no real relation to creatures, but a relation only in idea, inasmuch as creatures are referred to Him. Thus there is nothing to prevent these names which import relation to the creature from being predicated of God temporally, not by reason of any change in Him, but by reason of the change of the creature; as a column is on the right of an animal, without change in itself, but by change in the animal.

Because therefore God is not known to us in His nature, but is made known to us from His operations or effects, we name Him from these, as said in A. 1; hence this name God is a name of operation so far as relates to the source of its meaning. For this name is imposed from His universal providence over all things; since all who speak of God intend to name God as exercising providence over all; hence Dionysius says (Div. Nom. xii), The Deity watches over all with perfect providence and goodness. But taken from this operation, this name God is imposed to signify the divine nature.

Now from the divine effects we cannot know the divine nature in itself, so as to know what it is; but only by way of eminence, and by way of causality, and of negation as stated above (Q. 12, A. 12). Thus the name God signifies the divine nature, for this name was imposed to signify something existing above all things, the principle of all things and removed from all things; for those who name God intend to signify all this.

To know, however, what names are properly communicable, we must consider that every form existing in the singular subject, by which it is individualized, is common to many either in reality, or in idea; as human nature is common to many in reality, and in idea; whereas the nature of the sun is not common to many in reality, but only in idea; for the nature of the sun can be understood as existing in many subjects; and the reason is because the mind understands the nature of every species by abstraction from the singular. Hence to be in one singular subject or in many is outside the idea of the nature of the species. So, given the idea of a species, it can be understood as existing in many.

But the singular, from the fact that it is singular, is divided off from all others. Hence every name imposed to signify any singular thing is incommunicable both in reality and idea; for the plurality of this individual thing cannot be; nor can it be conceived in idea. Hence no name signifying any individual thing is properly communicable to many, but only by way of similitude; as for instance a person can be called Achilles metaphorically, forasmuch as he may possess something of the properties of Achilles, such as strength.

On the other hand, forms which are individualized not by any suppositum, but by and of themselves, as being subsisting forms, if understood as they are in themselves, could not be communicable either in reality or in idea; but only perhaps by way of similitude, as was said of individuals. Forasmuch as we are unable to understand simple self-subsisting forms as they really are, we understand them as compound things having forms in matter; therefore, as was said in the first article, we give them concrete names signifying a nature existing in some suppositum. Hence, so far as concerns images, the same rules apply to names we impose to signify the nature of compound things as to names given to us to signify simple subsisting natures.

Since, then, this name God is given to signify the divine nature as stated above (A. 8), and since the divine nature cannot be multiplied as shown above (Q. 11, A. 3), it follows that this name God is incommunicable in reality, but communicable in opinion; just in the same way as this name sun would be communicable according to the opinion of those who say there are many suns. Therefore, it is written: You served them who by nature are not gods, (Gal 4:8), and a gloss adds, Gods not in nature, but in human opinion. Nevertheless this name God is communicable, not in its whole signification, but in some part of it by way of similitude; so that those are called gods who share in divinity by likeness, according to the text, I have said, You are gods (Ps 81:6).

But if any name were given to signify God not as to His nature but as to His suppositum, accordingly as He is considered as this something, that name would be absolutely incommunicable; as, for instance, perhaps the Tetragrammaton among the Hebrew; and this is like giving a name to the sun as signifying this individual thing.

The same applies to the question at issue. For this name God, as signifying the true God, includes the idea of God when it is used to denote God in opinion, or participation. For when we name anyone god by participation, we understand by the name of god some likeness of the true God. Likewise, when we call an idol god, by this name god we understand and signify something which men think is God; thus it is manifest that the name has different meanings, but that one of them is comprised in the other significations. Hence it is manifestly said analogically.

The same remark applies to the Second and Third Objections. For these reasons proceed from the different predication of the name, and not from its various significations.

First, because of its signification. For it does not signify form, but simply existence itself. Hence since the existence of God is His essence itself, which can be said of no other (Q. 3, A. 4), it is clear that among other names this one specially denominates God, for everything is denominated by its form.

Second, on account of its universality. For all other names are either less universal, or, if convertible with it, add something above it at least in idea; hence in a certain way they inform and determine it. Now our intellect cannot know the essence of God itself in this life, as it is in itself, but whatever mode it applies in determining what it understands about God, it falls short of the mode of what God is in Himself. Therefore the less determinate the names are, and the more universal and absolute they are, the more properly they are applied to God. Hence Damascene says (De Fide Orth. i) that, HE WHO IS, is the principal of all names applied to God; for comprehending all in itself, it contains existence itself as an infinite and indeterminate sea of substance. Now by any other name some mode of substance is determined, whereas this name HE WHO IS, determines no mode of being, but is indeterminate to all; and therefore it denominates the infinite ocean of substance.

Third, from its consignification, for it signifies present existence; and this above all properly applies to God, whose existence knows not past or future, as Augustine says (De Trin. v).

And this appears to be the case both in propositions which have an accidental predicate, and in those which have an essential predicate. For it is manifest that man and white are the same in subject, and different in idea; for the idea of man is one thing, and that of whiteness is another. The same applies when I say, man is an animal, since the same thing which is man is truly animal; for in the same suppositum there is sensible nature by reason of which he is called animal, and the rational nature by reason of which he is called man; hence here again predicate and subject are the same as to suppositum, but different as to idea.

But in propositions where one same thing is predicated of itself, the same rule in some way applies, inasmuch as the intellect draws to the suppositum what it places in the subject; and what it places in the predicate it draws to the nature of the form existing in the suppositum; according to the saying that predicates are to be taken formally, and subjects materially. To this diversity in idea corresponds the plurality of predicate and subject, while the intellect signifies the identity of the thing by the composition itself.

God, however, as considered in Himself, is altogether one and simple, yet our intellect knows Him by different conceptions because it cannot see Him as He is in Himself. Nevertheless, although it understands Him under different conceptions, it knows that one and the same simple object corresponds to its conceptions. Therefore the plurality of predicate and subject represents the plurality of idea; and the intellect represents the unity by composition.

Now the contraction of the form comes from the matter. Hence, as we have said above (Q. 7, A. 1), forms according as they are the more immaterial, approach more nearly to a kind of infinity. Therefore it is clear that the immateriality of a thing is the reason why it is cognitive; and according to the mode of immateriality is the mode of knowledge. Hence it is said in De Anima ii that plants do not know, because they are wholly material. But sense is cognitive because it can receive images free from matter, and the intellect is still further cognitive, because it is more separated from matter and unmixed, as said in De Anima iii. Since therefore God is in the highest degree of immateriality as stated above (Q. 7, A. 1), it follows that He occupies the highest place in knowledge.

Since therefore God has nothing in Him of potentiality, but is pure act, His intellect and its object are altogether the same; so that He neither is without the intelligible species, as is the case with our intellect when it understands potentially; nor does the intelligible species differ from the substance of the divine intellect, as it differs in our intellect when it understands actually; but the intelligible species itself is the divine intellect itself, and thus God understands Himself through Himself.

Let us now consider how this is. As was laid down above (A. 2), to understand is not an act passing to anything extrinsic; for it remains in the operator as his own act and perfection; as existence is the perfection of the one existing: just as existence follows on the form, so in like manner to understand follows on the intelligible species. Now in God there is no form which is something other than His existence, as shown above (Q. 3). Hence as His essence itself is also His intelligible species, it necessarily follows that His act of understanding must be His essence and His existence.

Thus it follows from all the foregoing that in God, intellect, and the object understood, and the intelligible species, and His act of understanding are entirely one and the same. Hence when God is said to be understanding, no kind of multiplicity is attached to His substance.

Thus appears the Reply to the Third Objection. For the act of divine understanding subsists in itself, and belongs to its very self and is not another’s; hence it need not proceed to infinity.

And this appears still more plainly if we add that the very existence of the first effective cause—viz., God—is His own act of understanding. Hence whatever effects pre-exist in God, as in the first cause, must be in His act of understanding, and all things must be in Him according to an intelligible mode: for everything which is in another, is in it according to the mode of that in which it is.

Now in order to know how God knows things other than Himself, we must consider that a thing is known in two ways: in itself, and in another. A thing is known in itself when it is known by the proper species adequate to the knowable object; as when the eye sees a man through the image of a man. A thing is seen in another through the image of that which contains it; as when a part is seen in the whole by the image of the whole; or when a man is seen in a mirror by the image in the mirror, or by any other mode by which one thing is seen in another.

So we say that God sees Himself in Himself, because He sees Himself through His essence; and He sees other things not in themselves, but in Himself, inasmuch as His essence contains the similitude of things other than Himself.

But this cannot be. For to know a thing in general and not in particular, is to have an imperfect knowledge. Hence our intellect, when it is reduced from potentiality to act, acquires first a universal and confused knowledge of things before it knows them in particular; as proceeding from the imperfect to the perfect, as is clear from Phys. i. If therefore the knowledge of God regarding things other than Himself is only universal and not special, it would follow that His understanding would not be absolutely perfect; therefore neither would His being be perfect; and this is against what was said above (Q. 4, A. 1). We must therefore hold that God knows things other than Himself with a proper knowledge; not only in so far as being is common to them, but in so far as one is distinguished from the other. In proof thereof we may observe that some wishing to show that God knows many things by one, bring forward some examples, as, for instance, that if the center knew itself, it would know all lines that proceed from the center; or if light knew itself, it would know all colors.

Now these examples, although similar in part, namely, as regards universal causality, nevertheless fail in this respect, that multitude and diversity are caused by the one universal principle, not as regards that which is the principle of distinction, but only as regards that in which they communicate. For the diversity of colors is not caused by the light only, but by the different disposition of the diaphanous medium which receives it; and likewise, the diversity of the lines is caused by their different position. Hence it is that this kind of diversity and multitude cannot be known in its principle by proper knowledge, but only in a general way.

In God, however, it is otherwise. For it was shown above (Q. 4, A. 2) that whatever perfection exists in any creature, wholly pre-exists and is contained in God in an excelling manner. Now not only what is common to creatures—viz., being—belongs to their perfection, but also what makes them distinguished from each other; as living and understanding, and the like, whereby living beings are distinguished from the non-living, and the intelligent from the non-intelligent. Likewise every form whereby each thing is constituted in its own species, is a perfection; and thus all things pre-exist in God, not only as regards what is common to all, but also as regards what distinguishes one thing from another. And therefore as God contains all perfections in Himself, the essence of God is compared to all other essences of things, not as the common to the proper, as unity is to numbers, or as the center (of a circle) to the (radiating) lines; but as perfect acts to imperfect; as if I were to compare man to animal; or six, a perfect number, to the imperfect numbers contained under it. Now it is manifest that by a perfect act, imperfect acts can be known not only in general, but also by proper knowledge; thus, for example, whoever knows a man, knows an animal by proper knowledge; and whoever knows the number six, knows the number three also by proper knowledge.

As therefore the essence of God contains in itself all the perfection contained in the essence of any other being, and far more, God can know in Himself all of them with proper knowledge. For the nature proper to each thing consists in some degree of participation in the divine perfection. Now God could not be said to know Himself perfectly unless He knew all the ways in which His own perfection can be shared by others. Neither could He know the very nature of being perfectly, unless He knew all modes of being. Hence it is manifest that God knows all things with proper knowledge, in their distinction from each other.

We must say therefore that God not only knows that all things are in Himself; but by the fact that they are in Him, He knows them in their own nature and all the more perfectly, the more perfectly each one is in Him.

The first kind of discursion cannot belong to God. For many things, which we understand in succession if each is considered in itself, we understand simultaneously if we see them in some one thing; if, for instance, we understand the parts in the whole, or see different things in a mirror. Now God sees all things in one (thing), which is Himself. Therefore God sees all things together, and not successively.

Likewise the second mode of discursion cannot be applied to God. First, because this second mode of discursion presupposes the first mode; for whosoever proceeds from principles to conclusions does not consider both at once; second, because to discourse thus is to proceed from the known to the unknown. Hence it is manifest that when the first is known, the second is still unknown; and thus the second is known not in the first, but from the first. Now the term of discursive reasoning is attained when the second is seen in the first, by resolving the effects into their causes; and then the discursion ceases. Hence as God sees His effects in Himself as their cause, His knowledge is not discursive.

Now it is manifest that God causes things by His intellect, since His being is His act of understanding; and hence His knowledge must be the cause of things, in so far as His will is joined to it. Hence the knowledge of God as the cause of things is usually called the knowledge of approbation.

But when he says the reason why God foreknows some things is because they are future, this must be understood according to the cause of consequence, and not according to the cause of essence. For if things are in the future, it follows that God knows them; but not that the futurity of things is the cause of why God knows them.

Now a certain difference is to be noted in the consideration of those things that are not actual. For though some of them may not be in act now, still they were, or they will be; and God is said to know all these with the knowledge of vision: for since God’s act of understanding, which is His being, is measured by eternity; and since eternity is without succession, comprehending all time, the present glance of God extends over all time, and to all things which exist in any time, as to objects present to Him. But there are other things in God’s power, or the creature’s, which nevertheless are not, nor will be, nor were; and as regards these He is said to have knowledge, not of vision, but of simple intelligence. This is so called because the things we see around us have distinct being outside the seer.

Now some, wishing to show how this can be, said that God knows singular things by universal causes. For nothing exists in any singular thing, that does not arise from some universal cause. They give the example of an astrologer who knows all the universal movements of the heavens, and can thence foretell all eclipses that are to come. This, however, is not enough; for singular things from universal causes attain to certain forms and powers which, however they may be joined together, are not individualized except by individual matter. Hence he who knows Socrates because he is white, or because he is the son of Sophroniscus, or because of something of that kind, would not know him in so far as he is this particular man. Hence according to the aforesaid mode, God would not know singular things in their singularity.

On the other hand, others have said that God knows singular things by the application of universal causes to particular effects. But this will not hold, forasmuch as no one can apply a thing to another unless he first knows that thing; hence this application cannot be the reason of knowing the particular, for it presupposes the knowledge of singular things.

Therefore it must be said otherwise, that, since God is the cause of things by His knowledge, as stated above (A. 8), His knowledge extends as far as His causality extends. Hence as the active power of God extends not only to forms, which are the source of universality, but also to matter, as we shall prove further on (Q. 44, A. 2), the knowledge of God must extend to singular things, which are individualized by matter. For since He knows things other than Himself by His essence, as being the likeness of things, or as their active principle, His essence must be the sufficing principle of knowing all things made by Him, not only in the universal, but also in the singular. The same would apply to the knowledge of the artificer, if it were productive of the whole thing, and not only of the form.

The reason of this is to be found in the fact that the knowledge of every knower is measured by the mode of the form which is the principle of knowledge. For the sensible image in sense is the likeness of only one individual thing, and can give the knowledge of only one individual. But the intelligible species of our intellect is the likeness of the thing as regards its specific nature, which is participable by infinite particulars; hence our intellect by the intelligible species of man in a certain way knows infinite men; not however as distinguished from each other, but as communicating in the nature of the species; and the reason is because the intelligible species of our intellect is the likeness of man not as to the individual principles, but as to the principles of the species. On the other hand, the divine essence, whereby the divine intellect understands, is a sufficing likeness of all things that are, or can be, not only as regards the universal principles, but also as regards the principles proper to each one, as shown above. Hence it follows that the knowledge of God extends to infinite things, even as distinct from each other.

In evidence of this, we must consider that a contingent thing can be considered in two ways; first, in itself, in so far as it is now in act: and in this sense it is not considered as future, but as present; neither is it considered as contingent (as having reference) to one of two terms, but as determined to one; and on account of this it can be infallibly the object of certain knowledge, for instance to the sense of sight, as when I see that Socrates is sitting down. In another way a contingent thing can be considered as it is in its cause; and in this way it is considered as future, and as a contingent thing not yet determined to one; forasmuch as a contingent cause has relation to opposite things: and in this sense a contingent thing is not subject to any certain knowledge. Hence, whoever knows a contingent effect in its cause only, has merely a conjectural knowledge of it.

Now God knows all contingent things not only as they are in their causes, but also as each one of them is actually in itself. And although contingent things become actual successively, nevertheless God knows contingent things not successively, as they are in their own being, as we do; but simultaneously. The reason is because His knowledge is measured by eternity, as is also His being; and eternity being simultaneously whole comprises all time, as said above (Q. 10, A. 2). Hence all things that are in time are present to God from eternity, not only because He has the types of things present within Him, as some say; but because His glance is carried from eternity over all things as they are in their presentiality. Hence it is manifest that contingent things are infallibly known by God, inasmuch as they are subject to the divine sight in their presentiality; yet they are future contingent things in relation to their own causes.

On the other hand some say that this antecedent is contingent, because it is a compound of necessary and contingent; as this saying is contingent, Socrates is a white man. But this also is to no purpose; for when we say, God knew this contingent to be future, contingent is used here only as the matter of the word, and not as the chief part of the proposition. Hence its contingency or necessity has no reference to the necessity or contingency of the proposition, or to its being true or false. For it may be just as true that I said a man is an ass, as that I said Socrates runs, or God is: and the same applies to necessary and contingent. Hence it must be said that this antecedent is absolutely necessary.

Nor does it follow, as some say, that the consequent is absolutely necessary, because the antecedent is the remote cause of the consequent, which is contingent by reason of the proximate cause. But this is to no purpose. For the conditional would be false were its antecedent the remote necessary cause, and the consequent a contingent effect; as, for example, if I said, if the sun moves, the grass will grow.

Therefore we must reply otherwise, that when the antecedent contains anything belonging to an act of the soul, the consequent must be taken not as it is in itself, but as it is in the soul: for the existence of a thing in itself is different from the existence of a thing in the soul. For example, when I say, What the soul understands is immaterial, this is to be understood that it is immaterial as it is in the intellect, not as it is in itself. Likewise if I say, If God knew anything, it will be, the consequent must be understood as it is subject to the divine knowledge, i.e., as it is in its presentiality. And thus it is necessary, as also is the antecedent: For everything that is, while it is, must be necessarily be, as the Philosopher says (Peri Herm. i).

Now some urge an objection and say that this distinction holds good with regard to forms that are separable from the subject; thus if I said, It is possible for a white thing to be black, it is false as applied to the saying, and true as applied to the thing: for a thing which is white, can become black; whereas this saying, a white thing is black, can never be true. But in forms that are inseparable from the subject, this distinction does not hold, for instance, if I said, A black crow can be white; for in both senses it is false. Now to be known by God is inseparable from the thing; for what is known by God cannot be not known. This objection, however, would hold if these words that which is known implied any disposition inherent to the subject; but since they import an act of the knower, something can be attributed to the thing known, in itself (even if it always be known), which is not attributed to it in so far as it stands under actual knowledge; thus material existence is attributed to a stone in itself, which is not attributed to it inasmuch as it is known.

Now just as He knows material things immaterially, and composite things simply, so likewise He knows enunciable things not after the manner of enunciable things, as if in His intellect there were composition or division of enunciations; for He knows each thing by simple intelligence, by understanding the essence of each thing; as if we by the very fact that we understand what man is, were to understand all that can be predicated of man. This, however, does not happen in our intellect, which discourses from one thing to another, forasmuch as the intelligible species represents one thing in such a way as not to represent another. Hence when we understand what man is, we do not forthwith understand other things which belong to him, but we understand them one by one, according to a certain succession. On this account the things we understand as separated, we must reduce to one by way of composition or division, by forming an enunciation. Now the species of the divine intellect, which is God’s essence, suffices to represent all things. Hence by understanding His essence, God knows the essences of all things, and also whatever can be accidental to them.

We may also say that Lord, Creator and the like, import the relations consequent upon the acts which are understood as terminating in the creatures themselves, as they are in themselves; and thus these relations are attributed to God variously, according to the variation of creatures. But knowledge and love, and the like, import relations consequent upon the acts which are understood to be in God; and therefore these are predicated of God in an invariable manner.

Therefore, it must be conceded that this proposition is not true, Whatever God knew He knows, if referred to enunciable propositions. But because of this, it does not follow that the knowledge of God is variable. For as it is without variation in the divine knowledge that God knows one and the same thing sometime to be, and sometime not to be, so it is without variation in the divine knowledge that God knows an enunciable proposition is sometime true, and sometime false. The knowledge of God, however, would be variable if He knew enunciable things by way of enunciation, by composition and division, as occurs in our intellect. Hence our knowledge varies either as regards truth and falsity, for example, if when a thing suffers change we retained the same opinion about it; or as regards diverse opinions, as if we first thought that anyone was sitting, and afterwards thought that he was not sitting; neither of which can be in God.

In accordance with this, therefore, it must be said that God has of Himself a speculative knowledge only; for He Himself is not operable. But of all other things He has both speculative and practical knowledge. He has speculative knowledge as regards the mode; for whatever we know speculatively in things by defining and dividing, God knows all this much more perfectly.

Now of things which He can make, but does not make at any time, He has not a practical knowledge, according as knowledge is called practical from the end. But He has a practical knowledge of what He makes in some period of time. And, as regards evil things, although they are not operable by Him, yet they fall under His practical knowledge, like good things, inasmuch as He permits, or impedes, or directs them; as also sicknesses fall under the practical knowledge of the physician, inasmuch as he cures them by his art.

In answer to what is objected on the contrary, we must say that perfect knowledge of operable things is obtainable only if they are known in so far as they are operable. Therefore, since the knowledge of God is in every way perfect, He must know what is operable by Him, formally as such, and not only in so far as they are speculative. Nevertheless this does not impair the nobility of His speculative knowledge, forasmuch as He sees all things other than Himself in Himself, and He knows Himself speculatively; and so in the speculative knowledge of Himself, he possesses both speculative and practical knowledge of all other things.

In all things not generated by chance, the form must be the end of any generation whatsoever. But an agent does not act on account of the form, except in so far as the likeness of the form is in the agent, as may happen in two ways. For in some agents the form of the thing to be made pre-exists according to its natural being, as in those that act by their nature; as a man generates a man, or fire generates fire. Whereas in other agents (the form of the thing to be made pre-exists) according to intelligible being, as in those that act by the intellect; and thus the likeness of a house pre-exists in the mind of the builder. And this may be called the idea of the house, since the builder intends to build his house like to the form conceived in his mind. As then the world was not made by chance, but by God acting by His intellect, as will appear later (Q. 46, A. 1), there must exist in the divine mind a form to the likeness of which the world was made. And in this the notion of an idea consists.

Now it can easily be seen how this is not repugnant to the simplicity of God, if we consider that the idea of a work is in the mind of the operator as that which is understood, and not as the image whereby he understands, which is a form that makes the intellect in act. For the form of the house in the mind of the builder is something understood by him, to the likeness of which he forms the house in matter. Now, it is not repugnant to the simplicity of the divine mind that it understand many things; though it would be repugnant to its simplicity were His understanding to be formed by a plurality of images. Hence many ideas exist in the divine mind, as things understood by it.

As can be proved thus. Inasmuch as He knows His own essence perfectly, He knows it according to every mode in which it can be known. Now it can be known not only as it is in itself, but as it can be participated in by creatures according to some degree of likeness. But every creature has its own proper species, according to which it participates in some degree in likeness to the divine essence. So far, therefore, as God knows His essence as capable of such imitation by any creature, He knows it as the particular type and idea of that creature; and in like manner as regards other creatures. So it is clear that God understands many particular types of things and these are many ideas.

Now a thing understood may be in relation to an intellect either essentially or accidentally. It is related essentially to an intellect on which it depends as regards its essence; but accidentally to an intellect by which it is knowable; even as we may say that a house is related essentially to the intellect of the architect, but accidentally to the intellect upon which it does not depend.

Now we do not judge of a thing by what is in it accidentally, but by what is in it essentially. Hence, everything is said to be true absolutely, in so far as it is related to the intellect from which it depends; and thus it is that artificial things are said to be true as being related to our intellect. For a house is said to be true that expresses the likeness of the form in the architect’s mind; and words are said to be true so far as they are the signs of truth in the intellect. In the same way natural things are said to be true in so far as they express the likeness of the species that are in the divine mind. For a stone is called true, which possesses the nature proper to a stone, according to the preconception in the divine intellect. Thus, then, truth resides primarily in the intellect, and secondarily in things according as they are related to the intellect as their principle.

Consequently there are various definitions of truth. Augustine says (De Vera Relig. xxxvi), Truth is that whereby is made manifest that which is; and Hilary says (De Trin. v) that Truth makes being clear and evident and this pertains to truth according as it is in the intellect. As to the truth of things in so far as they are related to the intellect, we have Augustine’s definition (De Vera Relig. xxxvi), Truth is a supreme likeness without any unlikeness to a principle: also Anselm’s definition (De Verit. xii), Truth is rightness, perceptible by the mind alone; for that is right which is in accordance with the principle; also Avicenna’s definition (Metaph. viii, 6), The truth of each thing is a property of the essence which is immutably attached to it. The definition that Truth is the equation of thought and thing is applicable to it under either aspect.

This it does by composing and dividing: for in every proposition it either applies to, or removes from the thing signified by the subject, some form signified by the predicate: and this clearly shows that the sense is true of any thing, as is also the intellect, when it knows what a thing is; but it does not thereby know or affirm truth. This is in like manner the case with complex or non-complex words. Truth therefore may be in the senses, or in the intellect knowing what a thing is, as in anything that is true; yet not as the thing known in the knower, which is implied by the word truth; for the perfection of the intellect is truth as known. Therefore, properly speaking, truth resides in the intellect composing and dividing; and not in the senses; nor in the intellect knowing what a thing is.

And thus the Objections given are solved.

Now we have said (A. 1) that truth resides primarily in the intellect; and secondarily in things, according as they are related to the divine intellect. If therefore we speak of truth, as it exists in the intellect, according to its proper nature, then are there many truths in many created intellects; and even in one and the same intellect, according to the number of things known. Whence a gloss on Ps. 11:2, Truths are decayed from among the children of men, says: As from one man’s face many likenesses are reflected in a mirror, so many truths are reflected from the one divine truth. But if we speak of truth as it is in things, then all things are true by one primary truth; to which each one is assimilated according to its own entity. And thus, although the essences or forms of things are many, yet the truth of the divine intellect is one, in conformity to which all things are said to be true.

In things that depend on God, falseness cannot be found, in so far as they are compared with the divine intellect; since whatever takes place in things proceeds from the ordinance of that intellect, unless perhaps in the case of voluntary agents only, who have it in their power to withdraw themselves from what is so ordained; wherein consists the evil of sin. Thus sins themselves are called untruths and lies in the Scriptures, according to the words of the text, Why do you love vanity, and seek after lying? (Ps 4:3): as on the other hand virtuous deeds are called the truth of life as being obedient to the order of the divine intellect. Thus it is said, He that doth truth, cometh to the light (John 3:21).

But in relation to our intellect, natural things which are compared thereto accidentally, can be called false; not simply, but relatively; and that in two ways.

In one way according to the thing signified, and thus a thing is said to be false as being signified or represented by word or thought that is false. In this respect anything can be said to be false as regards any quality not possessed by it; as if we should say that a diameter is a false commensurable thing, as the Philosopher says (Metaph. v, 34). So, too, Augustine says (Soliloq. ii, 10): The true tragedian is a false Hector: even as, on the contrary, anything can be called true, in regard to that which is becoming to it.

In another way a thing can be called false, by way of cause—and thus a thing is said to be false that naturally begets a false opinion. And whereas it is innate in us to judge things by external appearances, since our knowledge takes its rise from sense, which principally and naturally deals with external accidents, therefore those external accidents, which resemble things other than themselves, are said to be false with respect to those things; thus gall is falsely honey; and tin, false gold. Regarding this, Augustine says (Soliloq. ii, 6): We call those things false that appear to our apprehension like the true: and the Philosopher says (Metaph. v, 34): Things are called false that are naturally apt to appear such as they are not, or what they are not. In this way a man is called false as delighting in false opinions or words, and not because he can invent them; for in this way many wise and learned persons might be called false, as stated in Metaph. v, 34.

The knowledge of things by the senses is in proportion to the existence of their likeness in the senses; and the likeness of a thing can exist in the senses in three ways. In the first way, primarily and of its own nature, as in sight there is the likeness of colors, and of other sensible objects proper to it. Second, of its own nature, though not primarily; as in sight there is the likeness of shape, size, and of other sensible objects common to more than one sense. Third, neither primarily nor of its own nature, but accidentally, as in sight, there is the likeness of a man, not as man, but in so far as it is accidental to the colored object to be a man.

Sense, then, has no false knowledge about its proper objects, except accidentally and rarely, and then, because of the unsound organ it does not receive the sensible form rightly; just as other passive subjects because of their indisposition receive defectively the impressions of the agent. Hence, for instance, it happens that on account of an unhealthy tongue sweet seems bitter to a sick person. But as to common objects of sense, and accidental objects, even a rightly disposed sense may have a false judgment, because it is referred to them not directly, but accidentally, or as a consequence of being directed to other things.

But in affirming and denying, the intellect may be deceived, by attributing to the thing of which it understands the essence, something which is not consequent upon it, or is opposed to it. For the intellect is in the same position as regards judging of such things, as sense is as to judging of common, or accidental, sensible objects. There is, however, this difference, as before mentioned regarding truth (Q. 16, A. 2), that falsity can exist in the intellect not only because the knowledge of the intellect is false, but because the intellect is conscious of that knowledge, as it is conscious of truth; whereas in sense, falsity does not exist as known, as stated above (A. 2).

But because falsity of the intellect is concerned essentially only with the composition of the intellect, falsity occurs also accidentally in that operation of the intellect whereby it knows the essence of a thing, in so far as composition of the intellect is mixed up in it. This can take place in two ways. In one way, by the intellect applying to one thing the definition proper to another; as that of a circle to a man. Wherefore the definition of one thing is false of another. In another way, by composing a definition of parts which are mutually exclusive. For thus the definition is not only false of the thing, but false in itself. A definition such as a reasonable four-footed animal would be of this kind, and the intellect false in making it; for such a statement as some reasonable animals are four-footed is false in itself. For this reason the intellect cannot be false in its knowledge of simple essences; but it is either true, or it understands nothing at all.

The same must be said of life. The name is given from a certain external appearance, namely, self-movement, yet not precisely to signify this, but rather a substance to which self-movement and the application of itself to any kind of operation, belong naturally. To live, accordingly, is nothing else than to exist in this or that nature; and life signifies this, though in the abstract, just as the word running denotes to run in the abstract. Hence living is not an accidental but an essential predicate.

Sometimes, however, life is used less properly for the operations from which its name is taken, and thus the Philosopher says (Ethic. ix, 9) that to live is principally to sense or to understand.

Wherefore the Reply to the Third Objection is clear.

Other things have self-movement in a higher degree, that is, not only with regard to executing the movement, but even as regards to the form, the principle of movement, which form they acquire of themselves. Of this kind are animals, in which the principle of movement is not a naturally implanted form; but one received through sense. Hence the more perfect is their sense, the more perfect is their power of self-movement. Such as have only the sense of touch, as shellfish, move only with the motion of expansion and contraction; and thus their movement hardly exceeds that of plants. Whereas such as have the sensitive power in perfection, so as to recognize not only connection and touch, but also objects apart from themselves, can move themselves to a distance by progressive movement. Yet although animals of the latter kind receive through sense the form that is the principle of their movement, nevertheless they cannot of themselves propose to themselves the end of their operation, or movement; for this has been implanted in them by nature; and by natural instinct they are moved to any action through the form apprehended by sense.

Hence such animals as move themselves in respect to an end they themselves propose are superior to these. This can only be done by reason and intellect; whose province it is to know the proportion between the end and the means to that end, and duly coordinate them. Hence a more perfect degree of life is that of intelligent beings; for their power of self-movement is more perfect. This is shown by the fact that in one and the same man the intellectual faculty moves the sensitive powers; and these by their command move the organs of movement. Thus in the arts we see that the art of using a ship, i.e., the art of navigation, rules the art of ship-designing; and this in its turn rules the art that is only concerned with preparing the material for the ship.

But although our intellect moves itself to some things, yet others are supplied by nature, as are first principles, which it cannot doubt; and the last end, which it cannot but will. Hence, although with respect to some things it moves itself, yet with regard to other things it must be moved by another. Wherefore that being whose act of understanding is its very nature, and which, in what it naturally possesses, is not determined by another, must have life in the most perfect degree. Such is God; and hence in Him principally is life. From this the Philosopher concludes (Metaph. xii, 51), after showing God to be intelligent, that God has life most perfect and eternal, since His intellect is most perfect and always in act.

Accordingly as to things willed by God, we must observe that He wills something of absolute necessity: but this is not true of all that He wills. For the divine will has a necessary relation to the divine goodness, since that is its proper object. Hence God wills His own goodness necessarily, even as we will our own happiness necessarily, and as any other faculty has necessary relation to its proper and principal object, for instance the sight to color, since it tends to it by its own nature. But God wills things apart from Himself in so far as they are ordered to His own goodness as their end. Now in willing an end we do not necessarily will things that conduce to it, unless they are such that the end cannot be attained without them; as, we will to take food to preserve life, or to take a ship in order to cross the sea. But we do not necessarily will things without which the end is attainable, such as a horse for a journey which we can take on foot, for we can make the journey without one. The same applies to other means. Hence, since the goodness of God is perfect, and can exist without other things inasmuch as no perfection can accrue to Him from them, it follows that His willing things apart from Himself is not absolutely necessary. Yet it can be necessary by supposition, for supposing that He wills a thing, then He is unable not to will it, as His will cannot change.

This can be shown in three ways: First, from the order itself of active causes. Since both intellect and nature act for an end, as proved in Phys. ii, 49, the natural agent must have the end and the necessary means predetermined for it by some higher intellect; as the end and definite movement is predetermined for the arrow by the archer. Hence the intellectual and voluntary agent must precede the agent that acts by nature. Hence, since God is first in the order of agents, He must act by intellect and will.

This is shown, second, from the character of a natural agent, of which the property is to produce one and the same effect; for nature operates in one and the same way unless it be prevented. This is because the nature of the act is according to the nature of the agent; and hence as long as it has that nature, its acts will be in accordance with that nature; for every natural agent has a determinate being. Since, then, the Divine Being is undetermined, and contains in Himself the full perfection of being, it cannot be that He acts by a necessity of His nature, unless He were to cause something undetermined and indefinite in being: and that this is impossible has been already shown (Q. 7, A. 2). He does not, therefore, act by a necessity of His nature, but determined effects proceed from His own infinite perfection according to the determination of His will and intellect.

Third, it is shown by the relation of effects to their cause. For effects proceed from the agent that causes them, in so far as they pre-exist in the agent; since every agent produces its like. Now effects pre-exist in their cause after the mode of the cause. Wherefore since the Divine Being is His own intellect, effects pre-exist in Him after the mode of intellect, and therefore proceed from Him after the same mode. Consequently, they proceed from Him after the mode of will, for His inclination to put in act what His intellect has conceived appertains to the will. Therefore the will of God is the cause of things.