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Thomas Aquinas

Summa Theologica, Part I

Thomas Aquinas · c. 1265–1274

Translated by Fathers of the English Dominican Province. Public domain edition from Project Gutenberg. Ponderspace organises the text; it belongs to whoever published it.

Every question stated with its strongest objections before any answer is given.

Part 25 of 57 · 1401 sections in this edition

As, therefore, the perfection of the universe requires that there should be not only beings incorruptible, but also corruptible beings; so the perfection of the universe requires that there should be some which can fail in goodness, and thence it follows that sometimes they do fail. Now it is in this that evil consists, namely, in the fact that a thing fails in goodness. Hence it is clear that evil is found in things, as corruption also is found; for corruption is itself an evil.

Reply Obj. 1: Evil is distant both from simple being and from simple "not-being," because it is neither a habit nor a pure negation, but a privation.

Reply Obj. 2: As the Philosopher says (Metaph. v, text 14), being is twofold. In one way it is considered as signifying the entity of a thing, as divisible by the ten "predicaments"; and in that sense it is convertible with thing, and thus no privation is a being, and neither therefore is evil a being. In another sense being conveys the truth of a proposition which unites together subject and attribute by a copula, notified by this word "is"; and in this sense being is what answers to the question, "Does it exist?" and thus we speak of blindness as being in the eye; or of any other privation. In this way even evil can be called a being. Through ignorance of this distinction some, considering that things may be evil, or that evil is said to be in things, believed that evil was a positive thing in itself.

Reply Obj. 3: God and nature and any other agent make what is best in the whole, but not what is best in every single part, except in order to the whole, as was said above (Q. 47, A. 2). And the whole itself, which is the universe of creatures, is all the better and more perfect if some things in it can fail in goodness, and do sometimes fail, God not preventing this. This happens, firstly, because "it belongs to Providence not to destroy, but to save nature," as Dionysius says (Div. Nom. iv); but it belongs to nature that what may fail should sometimes fail; secondly, because, as Augustine says (Enchir. 11), "God is so powerful that He can even make good out of evil." Hence many good things would be taken away if God permitted no evil to exist; for fire would not be generated if air was not corrupted, nor would the life of a lion be preserved unless the ass were killed. Neither would avenging justice nor the patience of a sufferer be praised if there were no injustice. _______________________

Whether Evil Is in Good As in Its Subject?

Objection 1: It would seem that evil is not in good as its subject. For good is something that exists. But Dionysius says (Div. Nom. iv, 4) that "evil does not exist, nor is it in that which exists." Therefore, evil is not in good as its subject.

Obj. 2: Further, evil is not a being; whereas good is a being. But "non-being" does not require being as its subject. Therefore, neither does evil require good as its subject.

Obj. 3: Further, one contrary is not the subject of another. But good and evil are contraries. Therefore, evil is not in good as in its subject.

Obj. 4: Further, the subject of whiteness is called white. Therefore also the subject of evil is evil. If, therefore, evil is in good as in its subject, it follows that good is evil, against what is said (Isa. 5:20): "Woe to you who call evil good, and good evil!"

_On the contrary,_ Augustine says (Enchiridion 14) that "evil exists only in good."

_I answer that,_ As was said above (A. 1), evil imports the absence of good. But not every absence of good is evil. For absence of good can be taken in a privative and in a negative sense. Absence of good, taken negatively, is not evil; otherwise, it would follow that what does not exist is evil, and also that everything would be evil, through not having the good belonging to something else; for instance, a man would be evil who had not the swiftness of the roe, or the strength of a lion. But the absence of good, taken in a privative sense, is an evil; as, for instance, the privation of sight is called blindness.

Now, the subject of privation and of form is one and the same--viz. being in potentiality, whether it be being in absolute potentiality, as primary matter, which is the subject of the substantial form, and of privation of the opposite form; or whether it be being in relative potentiality, and absolute actuality, as in the case of a transparent body, which is the subject both of darkness and light. It is, however, manifest that the form which makes a thing actual is a perfection and a good; and thus every actual being is a good; and likewise every potential being, as such, is a good, as having a relation to good. For as it has being in potentiality, so has it goodness in potentiality. Therefore, the subject of evil is good.

Reply Obj. 1: Dionysius means that evil is not in existing things as a part, or as a natural property of any existing thing.

Reply Obj. 2: "Not-being," understood negatively, does not require a subject; but privation is negation in a subject, as the Philosopher says (Metaph. iv, text 4), and such "not-being" is an evil.

Reply Obj. 3: Evil is not in the good opposed to it as in its subject, but in some other good, for the subject of blindness is not "sight," but "animal." Yet, it appears, as Augustine says (Enchiridion 13), that the rule of dialectics here fails, where it is laid down that contraries cannot exist together. But this is to be taken as referring to good and evil in general, but not in reference to any particular good and evil. For white and black, sweet and bitter, and the like contraries, are only considered as contraries in a special sense, because they exist in some determinate genus; whereas good enters into every genus. Hence one good can coexist with the privation of another good.

Reply Obj. 4: The prophet invokes woe to those who say that good as such is evil. But this does not follow from what is said above, as is clear from the explanation given. _______________________

Objection 1: It would seem that evil corrupts the whole good. For one contrary is wholly corrupted by another. But good and evil are contraries. Therefore evil corrupts the whole good.

Obj. 2: Further, Augustine says (Enchiridion 12) that "evil hurts inasmuch as it takes away good." But good is all of a piece and uniform. Therefore it is wholly taken away by evil.

Obj. 3: Further, evil, as long as it lasts, hurts, and takes away good. But that from which something is always being removed, is at some time consumed, unless it is infinite, which cannot be said of any created good. Therefore evil wholly consumes good.

_On the contrary,_ Augustine says (Enchiridion 12) that "evil cannot wholly consume good."

_I answer that,_ Evil cannot wholly consume good. To prove this we must consider that good is threefold. One kind of good is wholly destroyed by evil, and this is the good opposed to evil, as light is wholly destroyed by darkness, and sight by blindness. Another kind of good is neither wholly destroyed nor diminished by evil, and that is the good which is the subject of evil; for by darkness the substance of the air is not injured. And there is also a kind of good which is diminished by evil, but is not wholly taken away; and this good is the aptitude of a subject to some actuality.

The diminution, however, of this kind of good is not to be considered by way of subtraction, as diminution in quantity, but rather by way of remission, as diminution in qualities and forms. The remission likewise of this habitude is to be taken as contrary to its intensity. For this kind of aptitude receives its intensity by the dispositions whereby the matter is prepared for actuality; which the more they are multiplied in the subject the more is it fitted to receive its perfection and form; and, on the contrary, it receives its remission by contrary dispositions which, the more they are multiplied in the matter, and the more they are intensified, the more is the potentiality remitted as regards the actuality.

Therefore, if contrary dispositions cannot be multiplied and intensified to infinity, but only to a certain limit, neither is the aforesaid aptitude diminished or remitted infinitely, as appears in the active and passive qualities of the elements; for coldness and humidity, whereby the aptitude of matter to the form of fire is diminished or remitted, cannot be infinitely multiplied. But if the contrary dispositions can be infinitely multiplied, the aforesaid aptitude is also infinitely diminished or remitted; yet, nevertheless, it is not wholly taken away, because its root always remains, which is the substance of the subject. Thus, if opaque bodies were interposed to infinity between the sun and the air, the aptitude of the air to light would be infinitely diminished, but still it would never be wholly removed while the air remained, which in its very nature is transparent. Likewise, addition in sin can be made to infinitude, whereby the aptitude of the soul to grace is more and more lessened; and these sins, indeed, are like obstacles interposed between us and God, according to Isa. 59:2: "Our sins have divided between us and God." Yet the aforesaid aptitude of the soul is not wholly taken away, for it belongs to its very nature.

Reply Obj. 1: The good which is opposed to evil is wholly taken away; but other goods are not wholly removed, as said above.

Reply Obj. 2: The aforesaid aptitude is a medium between subject and act. Hence, where it touches act, it is diminished by evil; but where it touches the subject, it remains as it was. Therefore, although good is like to itself, yet, on account of its relation to different things, it is not wholly, but only partially taken away.

Reply Obj. 3: Some, imagining that the diminution of this kind of good is like the diminution of quantity, said that just as the continuous is infinitely divisible, if the division be made in an ever same proportion (for instance, half of half, or a third of a third), so is it in the present case. But this explanation does not avail here. For when in a division we keep the same proportion, we continue to subtract less and less; for half of half is less than half of the whole. But a second sin does not necessarily diminish the above mentioned aptitude less than a preceding sin, but perchance either equally or more.

Therefore it must be said that, although this aptitude is a finite thing, still it may be so diminished infinitely, not _per se,_ but accidentally; according as the contrary dispositions are also increased infinitely, as explained above. _______________________

Whether Evil Is Adequately Divided into Pain* and Fault?

[*Pain here means "penalty": such was its original signification, being derived from "poena." In this sense we say "Pain of death, Pain of loss, Pain of sense."--Ed.]

Objection 1: It would seem that evil is not adequately divided into pain and fault. For every defect is a kind of evil. But in all creatures there is the defect of not being able to preserve their own existence, which nevertheless is neither a pain nor a fault. Therefore evil is inadequately divided into pain and fault.

Obj. 2: Further, in irrational creatures there is neither fault nor pain; but, nevertheless, they have corruption and defect, which are evils. Therefore not every evil is a pain or a fault.

Obj. 3: Further, temptation is an evil, but it is not a fault; for "temptation which involves no consent, is not a sin, but an occasion for the exercise of virtue," as is said in a gloss on 2 Cor. 12; not is it a pain; because temptation precedes the fault, and the pain follows afterwards. Therefore, evil is not sufficiently divided into pain and fault.

Obj. 4: _On the contrary,_ It would seem that this division is superfluous: for, as Augustine says (Enchiridion 12), a thing is evil "because it hurts." But whatever hurts is penal. Therefore every evil comes under pain.

_I answer that,_ Evil, as was said above (A. 3), is the privation of good, which chiefly and of itself consists in perfection and act. Act, however, is twofold; first, and second. The first act is the form and integrity of a thing; the second act is its operation. Therefore evil also is twofold. In one way it occurs by the subtraction of the form, or of any part required for the integrity of the thing, as blindness is an evil, as also it is an evil to be wanting in any member of the body. In another way evil exists by the withdrawal of the due operation, either because it does not exist, or because it has not its due mode and order. But because good in itself is the object of the will, evil, which is the privation of good, is found in a special way in rational creatures which have a will. Therefore the evil which comes from the withdrawal of the form and integrity of the thing, has the nature of a pain; and especially so on the supposition that all things are subject to divine providence and justice, as was shown above (Q. 22, A. 2); for it is of the very nature of a pain to be against the will. But the evil which consists in the subtraction of the due operation in voluntary things has the nature of a fault; for this is imputed to anyone as a fault to fail as regards perfect action, of which he is master by the will. Therefore every evil in voluntary things is to be looked upon as a pain or a fault.

Reply Obj. 1: Because evil is the privation of good, and not a mere negation, as was said above (A. 3), therefore not every defect of good is an evil, but the defect of the good which is naturally due. For the want of sight is not an evil in a stone, but it is an evil in an animal; since it is against the nature of a stone to see. So, likewise, it is against the nature of a creature to be preserved in existence by itself, because existence and conservation come from one and the same source. Hence this kind of defect is not an evil as regards a creature.

Reply Obj. 2: Pain and fault do not divide evil absolutely considered, but evil that is found in voluntary things.

Reply Obj. 3: Temptation, as importing provocation to evil, is always an evil of fault in the tempter; but in the one tempted it is not, properly speaking, a fault; unless through the temptation some change is wrought in the one who is tempted; for thus is the action of the agent in the patient. And if the tempted is changed to evil by the tempter he falls into fault.

Reply Obj. 4: In answer to the opposite argument, it must be said that the very nature of pain includes the idea of injury to the agent in himself, whereas the idea of fault includes the idea of injury to the agent in his operation; and thus both are contained in evil, as including the idea of injury. _______________________

Whether Pain Has the Nature of Evil More Than Fault Has?

Objection 1: It would seem that pain has more of evil than fault. For fault is to pain what merit is to reward. But reward has more good than merit, as its end. Therefore pain has more evil in it than fault has.

Obj. 2: Further, that is the greater evil which is opposed to the greater good. But pain, as was said above (A. 5), is opposed to the good of the agent, while fault is opposed to the good of the action. Therefore, since the agent is better than the action, it seems that pain is worse than fault.

Obj. 3: Further, the privation of the end is a pain consisting in forfeiting the vision of God; whereas the evil of fault is privation of the order to the end. Therefore pain is a greater evil than fault.

_On the contrary,_ A wise workman chooses a less evil in order to prevent a greater, as the surgeon cuts off a limb to save the whole body. But divine wisdom inflicts pain to prevent fault. Therefore fault is a greater evil than pain.

_I answer that,_ Fault has the nature of evil more than pain has; not only more than pain of sense, consisting in the privation of corporeal goods, which kind of pain appeals to most men; but also more than any kind of pain, thus taking pain in its most general meaning, so as to include privation of grace or glory.

There is a twofold reason for this. The first is that one becomes evil by the evil of fault, but not by the evil of pain, as Dionysius says (Div. Nom. iv): "To be punished is not an evil; but it is an evil to be made worthy of punishment." And this because, since good absolutely considered consists in act, and not in potentiality, and the ultimate act is operation, or the use of something possessed, it follows that the absolute good of man consists in good operation, or the good use of something possessed. Now we use all things by the act of the will. Hence from a good will, which makes a man use well what he has, man is called good, and from a bad will he is called bad. For a man who has a bad will can use ill even the good he has, as when a grammarian of his own will speaks incorrectly. Therefore, because the fault itself consists in the disordered act of the will, and the pain consists in the privation of something used by the will, fault has more of evil in it than pain has.

The second reason can be taken from the fact that God is the author of the evil of pain, but not of the evil of fault. And this is because the evil of pain takes away the creature's good, which may be either something created, as sight, destroyed by blindness, or something uncreated, as by being deprived of the vision of God, the creature forfeits its uncreated good. But the evil of fault is properly opposed to uncreated good; for it is opposed to the fulfilment of the divine will, and to divine love, whereby the divine good is loved for itself, and not only as shared by the creature. Therefore it is plain that fault has more evil in it than pain has.

Reply Obj. 1: Although fault results in pain, as merit in reward, yet fault is not intended on account of the pain, as merit is for the reward; but rather, on the contrary, pain is brought about so that the fault may be avoided, and thus fault is worse than pain.

Reply Obj. 2: The order of action which is destroyed by fault is the more perfect good of the agent, since it is the second perfection, than the good taken away by pain, which is the first perfection.

Reply Obj. 3: Pain and fault are not to be compared as end and order to the end; because one may be deprived of both of these in some way, both by fault and by pain; by pain, accordingly as a man is removed from the end and from the order to the end; by fault, inasmuch as this privation belongs to the action which is not ordered to its due end. _______________________

We next inquire into the cause of evil. Concerning this there are three points of inquiry:

(1) Whether good can be the cause of evil?

(2) Whether the supreme good, God, is the cause of evil?

(3) Whether there be any supreme evil, which is the first cause of all evils? _______________________

Objection 1: It would seem that good cannot be the cause of evil. For it is said (Matt. 7:18): "A good tree cannot bring forth evil fruit."

Obj. 2: Further, one contrary cannot be the cause of another. But evil is the contrary to good. Therefore good cannot be the cause of evil.

Obj. 3: Further, a deficient effect can proceed only from a deficient cause. But evil is a deficient effect. Therefore its cause, if it has one, is deficient. But everything deficient is an evil. Therefore the cause of evil can only be evil.

Obj. 4: Further, Dionysius says (Div. Nom. iv) that evil has no cause. Therefore good is not the cause of evil.

_On the contrary,_ Augustine says (Contra Julian. i, 9): "There is no possible source of evil except good."

_I answer that,_ It must be said that every evil in some way has a cause. For evil is the absence of the good, which is natural and due to a thing. But that anything fail from its natural and due disposition can come only from some cause drawing it out of its proper disposition. For a heavy thing is not moved upwards except by some impelling force; nor does an agent fail in its action except from some impediment. But only good can be a cause; because nothing can be a cause except inasmuch as it is a being, and every being, as such, is good.

And if we consider the special kinds of causes, we see that the agent, the form, and the end, import some kind of perfection which belongs to the notion of good. Even matter, as a potentiality to good, has the nature of good. Now that good is the cause of evil by way of the material cause was shown above (Q. 48, A. 3). For it was shown that good is the subject of evil. But evil has no formal cause, rather is it a privation of form; likewise, neither has it a final cause, but rather is it a privation of order to the proper end; since not only the end has the nature of good, but also the useful, which is ordered to the end. Evil, however, has a cause by way of an agent, not directly, but accidentally.

In proof of this, we must know that evil is caused in the action otherwise than in the effect. In the action evil is caused by reason of the defect of some principle of action, either of the principal or the instrumental agent; thus the defect in the movement of an animal may happen by reason of the weakness of the motive power, as in the case of children, or by reason only of the ineptitude of the instrument, as in the lame. On the other hand, evil is caused in a thing, but not in the proper effect of the agent, sometimes by the power of the agent, sometimes by reason of a defect, either of the agent or of the matter. It is caused by reason of the power or perfection of the agent when there necessarily follows on the form intended by the agent the privation of another form; as, for instance, when on the form of fire there follows the privation of the form of air or of water. Therefore, as the more perfect the fire is in strength, so much the more perfectly does it impress its own form, so also the more perfectly does it corrupt the contrary. Hence that evil and corruption befall air and water comes from the perfection of the fire: but this is accidental; because fire does not aim at the privation of the form of water, but at the bringing in of its own form, though by doing this it also accidentally causes the other. But if there is a defect in the proper effect of the fire--as, for instance, that it fails to heat--this comes either by defect of the action, which implies the defect of some principle, as was said above, or by the indisposition of the matter, which does not receive the action of the fire, the agent. But this very fact that it is a deficient being is accidental to good to which of itself it belongs to act. Hence it is true that evil in no way has any but an accidental cause; and thus is good the cause of evil.

Reply Obj. 1: As Augustine says (Contra Julian. i): "The Lord calls an evil will the evil tree, and a good will a good tree." Now, a good will does not produce a morally bad act, since it is from the good will itself that a moral act is judged to be good. Nevertheless the movement itself of an evil will is caused by the rational creature, which is good; and thus good is the cause of evil.

Reply Obj. 2: Good does not cause that evil which is contrary to itself, but some other evil: thus the goodness of the fire causes evil to the water, and man, good as to his nature, causes an act morally evil. And, as explained above (Q. 19, A. 9), this is by accident. Moreover, it does happen sometimes that one contrary causes another by accident: for instance, the exterior surrounding cold heats (the body) through the concentration of the inward heat.

Reply Obj. 3: Evil has a deficient cause in voluntary things otherwise than in natural things. For the natural agent produces the same kind of effect as it is itself, unless it is impeded by some exterior thing; and this amounts to some defect belonging to it. Hence evil never follows in the effect, unless some other evil pre-exists in the agent or in the matter, as was said above. But in voluntary things the defect of the action comes from the will actually deficient, inasmuch as it does not actually subject itself to its proper rule. This defect, however, is not a fault, but fault follows upon it from the fact that the will acts with this defect.

Reply Obj. 4: Evil has no direct cause, but only an accidental cause, as was said above. _______________________

Whether the Supreme Good, God, Is the Cause of Evil?

Objection 1: It would seem that the supreme good, God, is the cause of evil. For it is said (Isa. 45:5,7): "I am the Lord, and there is no other God, forming the light, and creating darkness, making peace, and creating evil." And Amos 3:6, "Shall there be evil in a city, which the Lord hath not done?"

Obj. 2: Further, the effect of the secondary cause is reduced to the first cause. But good is the cause of evil, as was said above (A. 1). Therefore, since God is the cause of every good, as was shown above (Q. 2, A. 3; Q. 6, AA. 1, 4), it follows that also every evil is from God.

Obj. 3: Further, as is said by the Philosopher (Phys. ii, text 30), the cause of both safety and danger of the ship is the same. But God is the cause of the safety of all things. Therefore He is the cause of all perdition and of all evil.

_On the contrary,_ Augustine says (QQ. 83, qu. 21), that, "God is not the author of evil because He is not the cause of tending to not-being."

_I answer that,_ As appears from what was said (A. 1), the evil which consists in the defect of action is always caused by the defect of the agent. But in God there is no defect, but the highest perfection, as was shown above (Q. 4, A. 1). Hence, the evil which consists in defect of action, or which is caused by defect of the agent, is not reduced to God as to its cause.

But the evil which consists in the corruption of some things is reduced to God as the cause. And this appears as regards both natural things and voluntary things. For it was said (A. 1) that some agent inasmuch as it produces by its power a form to which follows corruption and defect, causes by its power that corruption and defect. But it is manifest that the form which God chiefly intends in things created is the good of the order of the universe. Now, the order of the universe requires, as was said above (Q. 22, A. 2, ad 2; Q. 48, A. 2), that there should be some things that can, and do sometimes, fail. And thus God, by causing in things the good of the order of the universe, consequently and as it were by accident, causes the corruptions of things, according to 1 Kings 2:6: "The Lord killeth and maketh alive." But when we read that "God hath not made death" (Wis. 1:13), the sense is that God does not will death for its own sake. Nevertheless the order of justice belongs to the order of the universe; and this requires that penalty should be dealt out to sinners. And so God is the author of the evil which is penalty, but not of the evil which is fault, by reason of what is said above.

Reply Obj. 1: These passages refer to the evil of penalty, and not to the evil of fault.

Reply Obj. 2: The effect of the deficient secondary cause is reduced to the first non-deficient cause as regards what it has of being and perfection, but not as regards what it has of defect; just as whatever there is of motion in the act of limping is caused by the motive power, whereas what there is of obliqueness in it does not come from the motive power, but from the curvature of the leg. And, likewise, whatever there is of being and action in a bad action, is reduced to God as the cause; whereas whatever defect is in it is not caused by God, but by the deficient secondary cause.

Reply Obj. 3: The sinking of a ship is attributed to the sailor as the cause, from the fact that he does not fulfil what the safety of the ship requires; but God does not fail in doing what is necessary for the safety of all. Hence there is no parity. _______________________

Whether There Be One Supreme Evil Which Is the Cause of Every Evil?

Objection 1: It would seem that there is one supreme evil which is the cause of every evil. For contrary effects have contrary causes. But contrariety is found in things, according to Ecclus. 33:15: "Good is set against evil, and life against death; so also is the sinner against a just man." Therefore there are many contrary principles, one of good, the other of evil.

Obj. 2: Further, if one contrary is in nature, so is the other. But the supreme good is in nature, and is the cause of every good, as was shown above (Q. 2, A. 3; Q. 6, AA. 2, 4). Therefore, also, there is a supreme evil opposed to it as the cause of every evil.

Obj. 3: Further, as we find good and better things, so we find evil and worse. But good and better are so considered in relation to what is best. Therefore evil and worse are so considered in relation to some supreme evil.

Obj. 4: Further, everything participated is reduced to what is essential. But things which are evil among us are evil not essentially, but by participation. Therefore we must seek for some supreme essential evil, which is the cause of every evil.

Obj. 5: Further, whatever is accidental is reduced to that which is _per se._ But good is the accidental cause of evil. Therefore, we must suppose some supreme evil which is the _per se_ cause of evils. Nor can it be said that evil has no _per se_ cause, but only an accidental cause; for it would then follow that evil would not exist in the many, but only in the few.

Obj. 6: Further, the evil of the effect is reduced to the evil of the cause; because the deficient effect comes from the deficient cause, as was said above (AA. 1, 2). But we cannot proceed to infinity in this matter. Therefore, we must suppose one first evil as the cause of every evil.

_On the contrary,_ The supreme good is the cause of every being, as was shown above (Q. 2, A. 3; Q. 6, A. 4). Therefore there cannot be any principle opposed to it as the cause of evils.

_I answer that,_ It appears from what precedes that there is no one first principle of evil, as there is one first principle of good.

First, indeed, because the first principle of good is essentially good, as was shown above (Q. 6, AA. 3, 4). But nothing can be essentially bad. For it was shown above that every being, as such, is good (Q. 5, A. 3); and that evil can exist only in good as in its subject (Q. 48, A. 3).

Secondly, because the first principle of good is the highest and perfect good which pre-contains in itself all goodness, as shown above (Q. 6, A. 2). But there cannot be a supreme evil; because, as was shown above (Q. 48, A. 4), although evil always lessens good, yet it never wholly consumes it; and thus, while good ever remains, nothing can be wholly and perfectly bad. Therefore, the Philosopher says (Ethic. iv, 5) that "if the wholly evil could be, it would destroy itself"; because all good being destroyed (which it need be for something to be wholly evil), evil itself would be taken away, since its subject is good.

Thirdly, because the very nature of evil is against the idea of a first principle; both because every evil is caused by good, as was shown above (A. 1), and because evil can be only an accidental cause, and thus it cannot be the first cause, for the accidental cause is subsequent to the direct cause.

Those, however, who upheld two first principles, one good and the other evil, fell into this error from the same cause, whence also arose other strange notions of the ancients; namely, because they failed to consider the universal cause of all being, and considered only the particular causes of particular effects. For on that account, if they found a thing hurtful to something by the power of its own nature, they thought that the very nature of that thing was evil; as, for instance, if one should say that the nature of fire was evil because it burnt the house of a poor man. The judgment, however, of the goodness of anything does not depend upon its order to any particular thing, but rather upon what it is in itself, and on its order to the whole universe, wherein every part has its own perfectly ordered place, as was said above (Q. 47, A. 2, ad 1).

Likewise, because they found two contrary particular causes of two contrary particular effects, they did not know how to reduce these contrary particular causes to the universal common cause; and therefore they extended the contrariety of causes even to the first principles. But since all contraries agree in something common, it is necessary to search for one common cause for them above their own contrary proper causes; as above the contrary qualities of the elements exists the power of a heavenly body; and above all things that exist, no matter how, there exists one first principle of being, as was shown above (Q. 2, A. 3).

Reply Obj. 1: Contraries agree in one genus, and they also agree in the nature of being; and therefore, although they have contrary particular causes, nevertheless we must come at last to one first common cause.

Reply Obj. 2: Privation and habit belong naturally to the same subject. Now the subject of privation is a being in potentiality, as was said above (Q. 48, A. 3). Hence, since evil is privation of good, as appears from what was said above (Q. 48, AA. 1, 2, 3), it is opposed to that good which has some potentiality, but not to the supreme good, who is pure act.

Reply Obj. 3: Increase in intensity is in proportion to the nature of a thing. And as the form is a perfection, so privation removes a perfection. Hence every form, perfection, and good is intensified by approach to the perfect term; but privation and evil by receding from that term. Hence a thing is not said to be evil and worse, by reason of access to the supreme evil, in the same way as it is said to be good and better, by reason of access to the supreme good.

Reply Obj. 4: No being is called evil by participation, but by privation of participation. Hence it is not necessary to reduce it to any essential evil.

Reply Obj. 5: Evil can only have an accidental cause, as was shown above (A. 1). Hence reduction to any 'per se' cause of evil is impossible. And to say that evil is in the greater number is simply false. For things which are generated and corrupted, in which alone can there be natural evil, are the smaller part of the whole universe. And again, in every species the defect of nature is in the smaller number. In man alone does evil appear as in the greater number; because the good of man as regards the senses is not the good of man as man--that is, in regard to reason; and more men seek good in regard to the senses than good according to reason.

Reply Obj. 6: In the causes of evil we do not proceed to infinity, but reduce all evils to some good cause, whence evil follows accidentally. _______________________

TREATISE ON THE ANGELS (QQ. 50-64) _______________________

OF THE SUBSTANCE OF THE ANGELS ABSOLUTELY CONSIDERED (In Five Articles)

Now we consider the distinction of corporeal and spiritual creatures: firstly, the purely spiritual creature which in Holy Scripture is called angel; secondly, the creature wholly corporeal; thirdly, the composite creature, corporeal and spiritual, which is man.

Concerning the angels, we consider first what belongs to their substance; secondly, what belongs to their intellect; thirdly, what belongs to their will; fourthly, what belongs to their creation.

Their substance we consider absolutely and in relation to corporeal things.

Concerning their substance absolutely considered, there are five points of inquiry:

(1) Whether there is any entirely spiritual creature, altogether incorporeal?

(2) Supposing that an angel is such, we ask whether it is composed of matter and form?

(5) Of their immortality or incorruptibility. _______________________

Whether an Angel Is Altogether Incorporeal?

Objection 1: It would seem that an angel is not entirely incorporeal. For what is incorporeal only as regards ourselves, and not in relation to God, is not absolutely incorporeal. But Damascene says (De Fide Orth. ii) that "an angel is said to be incorporeal and immaterial as regards us; but compared to God it is corporeal and material. Therefore he is not simply incorporeal."

Obj. 2: Further, nothing is moved except a body, as the Philosopher says (Phys. vi, text 32). But Damascene says (De Fide Orth. ii) that "an angel is an ever movable intellectual substance." Therefore an angel is a corporeal substance.

Obj. 3: Further, Ambrose says (De Spir. Sanct. i, 7): "Every creature is limited within its own nature." But to be limited belongs to bodies. Therefore, every creature is corporeal. Now angels are God's creatures, as appears from Ps. 148:2: "Praise ye" the Lord, "all His angels"; and, farther on (verse 4), "For He spoke, and they were made; He commanded, and they were created." Therefore angels are corporeal.

_On the contrary,_ It is said (Ps. 103:4): "Who makes His angels spirits."

_I answer that,_ There must be some incorporeal creatures. For what is principally intended by God in creatures is good, and this consists in assimilation to God Himself. And the perfect assimilation of an effect to a cause is accomplished when the effect imitates the cause according to that whereby the cause produces the effect; as heat makes heat. Now, God produces the creature by His intellect and will (Q. 14, A. 8; Q. 19, A. 4). Hence the perfection of the universe requires that there should be intellectual creatures. Now intelligence cannot be the action of a body, nor of any corporeal faculty; for every body is limited to "here" and "now." Hence the perfection of the universe requires the existence of an incorporeal creature.

The ancients, however, not properly realizing the force of intelligence, and failing to make a proper distinction between sense and intellect, thought that nothing existed in the world but what could be apprehended by sense and imagination. And because bodies alone fall under imagination, they supposed that no being existed except bodies, as the Philosopher observes (Phys. iv, text 52,57). Thence came the error of the Sadducees, who said there was no spirit (Acts 23:8).

But the very fact that intellect is above sense is a reasonable proof that there are some incorporeal things comprehensible by the intellect alone.

Reply Obj. 1: Incorporeal substances rank between God and corporeal creatures. Now the medium compared to one extreme appears to be the other extreme, as what is tepid compared to heat seems to be cold; and thus it is said that angels, compared to God, are material and corporeal, not, however, as if anything corporeal existed in them.

Reply Obj. 2: Movement is there taken in the sense in which it is applied to intelligence and will. Therefore an angel is called an ever mobile substance, because he is ever actually intelligent, and not as if he were sometimes actually and sometimes potentially, as we are. Hence it is clear that the objection rests on an equivocation.

Reply Obj. 3: To be circumscribed by local limits belongs to bodies only; whereas to be circumscribed by essential limits belongs to all creatures, both corporeal and spiritual. Hence Ambrose says (De Spir. Sanct. i, 7) that "although some things are not contained in corporeal place, still they are none the less circumscribed by their substance." _______________________

Whether an Angel Is Composed of Matter and Form?

Objection 1: It would seem that an angel is composed of matter and form. For everything which is contained under any genus is composed of the genus, and of the difference which added to the genus makes the species. But the genus comes from the matter, and the difference from the form (Metaph. xiii, text 6). Therefore everything which is in a genus is composed of matter and form. But an angel is in the genus of substance. Therefore he is composed of matter and form.

Obj. 2: Further, wherever the properties of matter exist, there is matter. Now the properties of matter are to receive and to substand; whence Boethius says (De Trin.) that "a simple form cannot be a subject": and the above properties are found in the angel. Therefore an angel is composed of matter and form.

Obj. 3: Further, form is act. So what is form only is pure act. But an angel is not pure act, for this belongs to God alone. Therefore an angel is not form only, but has a form in matter.

Obj. 4: Further, form is properly limited and perfected by matter. So the form which is not in matter is an infinite form. But the form of an angel is not infinite, for every creature is finite. Therefore the form of an angel is in matter.

_On the contrary,_ Dionysius says (Div. Nom. iv): "The first creatures are understood to be as immaterial as they are incorporeal."

_I answer that,_ Some assert that the angels are composed of matter and form; which opinion Avicebron endeavored to establish in his book of the _Fount of Life._ For he supposes that whatever things are distinguished by the intellect are really distinct. Now as regards incorporeal substance, the intellect apprehends that which distinguishes it from corporeal substance, and that which it has in common with it. Hence he concludes that what distinguishes incorporeal from corporeal substance is a kind of form to it, and whatever is subject to this distinguishing form, as it were something common, is its matter. Therefore, he asserts the universal matter of spiritual and corporeal things is the same; so that it must be understood that the form of incorporeal substance is impressed in the matter of spiritual things, in the same way as the form of quantity is impressed in the matter of corporeal things.

But one glance is enough to show that there cannot be one matter of spiritual and of corporeal things. For it is not possible that a spiritual and a corporeal form should be received into the same part of matter, otherwise one and the same thing would be corporeal and spiritual. Hence it would follow that one part of matter receives the corporeal form, and another receives the spiritual form. Matter, however, is not divisible into parts except as regarded under quantity; and without quantity substance is indivisible, as Aristotle says (Phys. i, text 15). Therefore it would follow that the matter of spiritual things is subject to quantity; which cannot be. Therefore it is impossible that corporeal and spiritual things should have the same matter.

It is, further, impossible for an intellectual substance to have any kind of matter. For the operation belonging to anything is according to the mode of its substance. Now to understand is an altogether immaterial operation, as appears from its object, whence any act receives its species and nature. For a thing is understood according to its degree of immateriality; because forms that exist in matter are individual forms which the intellect cannot apprehend as such. Hence it must be that every individual substance is altogether immaterial.

But things distinguished by the intellect are not necessarily distinguished in reality; because the intellect does not apprehend things according to their mode, but according to its own mode. Hence material things which are below our intellect exist in our intellect in a simpler mode than they exist in themselves. Angelic substances, on the other hand, are above our intellect; and hence our intellect cannot attain to apprehend them, as they are in themselves, but by its own mode, according as it apprehends composite things; and in this way also it apprehends God (Q. 3).

Reply Obj. 1: It is difference which constitutes the species. Now everything is constituted in a species according as it is determined to some special grade of being because "the species of things are like numbers," which differ by addition and subtraction of unity, as the Philosopher says (Metaph. viii, text 10). But in material things there is one thing which determines to a special grade, and that is the form; and another thing which is determined, and this is the matter; and hence from the latter the genus is derived, and from the former the "difference." Whereas in immaterial things there is no separate determinator and thing determined; each thing by its own self holds a determinate grade in being; and therefore in them genus and "difference" are not derived from different things, but from one and the same. Nevertheless, this differs in our mode of conception; for, inasmuch as our intellect considers it as indeterminate, it derives the idea of their genus; and inasmuch as it considers it determinately, it derives the idea of their "difference."

Reply Obj. 2: This reason is given in the book on the _Fount of Life,_ and it would be cogent, supposing that the receptive mode of the intellect and of matter were the same. But this is clearly false. For matter receives the form, that thereby it may be constituted in some species, either of air, or of fire, or of something else. But the intellect does not receive the form in the same way; otherwise the opinion of Empedocles (De Anima i, 5, text 26) would be true, to the effect that we know earth by earth, and fire by fire. But the intelligible form is in the intellect according to the very nature of a form; for as such is it so known by the intellect. Hence such a way of receiving is not that of matter, but of an immaterial substance.

Reply Obj. 3: Although there is no composition of matter and form in an angel, yet there is act and potentiality. And this can be made evident if we consider the nature of material things which contain a twofold composition. The first is that of form and matter, whereby the nature is constituted. Such a composite nature is not its own existence but existence is its act. Hence the nature itself is related to its own existence as potentiality to act. Therefore if there be no matter, and supposing that the form itself subsists without matter, there nevertheless still remains the relation of the form to its very existence, as of potentiality to act. And such a kind of composition is understood to be in the angels; and this is what some say, that an angel is composed of, "whereby he is," and "what is," or "existence," and "what is," as Boethius says. For "what is," is the form itself subsisting; and the existence itself is whereby the substance is; as the running is whereby the runner runs. But in God "existence" and "what is" are not different as was explained above (Q. 3, A. 4). Hence God alone is pure act.

Reply Obj. 4: Every creature is simply finite, inasmuch as its existence is not absolutely subsisting, but is limited to some nature to which it belongs. But there is nothing against a creature being considered relatively infinite. Material creatures are infinite on the part of matter, but finite in their form, which is limited by the matter which receives it. But immaterial created substances are finite in their being; whereas they are infinite in the sense that their forms are not received in anything else; as if we were to say, for example, that whiteness existing separate is infinite as regards the nature of whiteness, forasmuch as it is not contracted to any one subject; while its "being" is finite as determined to some one special nature.

Whence it is said (De Causis, prop. 16) that "intelligence is finite from above," as receiving its being from above itself, and is "infinite from below," as not received in any matter. _______________________

Whether the Angels Exist in Any Great Number?

Objection 1: It would seem that the angels are not in great numbers. For number is a species of quantity, and follows the division of a continuous body. But this cannot be in the angels, since they are incorporeal, as was shown above (A. 1). Therefore the angels cannot exist in any great number.

Obj. 2: Further, the more a thing approaches to unity, so much the less is it multiplied, as is evident in numbers. But among other created natures the angelic nature approaches nearest to God. Therefore since God is supremely one, it seems that there is the least possible number in the angelic nature.

Obj. 3: Further, the proper effect of the separate substances seems to be the movements of the heavenly bodies. But the movements of the heavenly bodies fall within some small determined number, which we can apprehend. Therefore the angels are not in greater number than the movements of the heavenly bodies.

Obj. 4: Dionysius says (Div. Nom. iv) that "all intelligible and intellectual substances subsist because of the rays of the divine goodness." But a ray is only multiplied according to the different things that receive it. Now it cannot be said that their matter is receptive of an intelligible ray, since intellectual substances are immaterial, as was shown above (A. 2). Therefore it seems that the multiplication of intellectual substances can only be according to the requirements of the first bodies--that is, of the heavenly ones, so that in some way the shedding form of the aforesaid rays may be terminated in them; and hence the same conclusion is to be drawn as before.