Summa Theologica, by St. Thomas Aquinas, [1947], at sacred-texts.com
After the foregoing we must consider the first production of man, concerning which there are four subjects of treatment: (1) the production of man himself; (2) the end of this production; (3) the state and condition of the first man; (4) the place of his abode. Concerning the production of man, there are three things to be considered: (1) the production of man's soul; (2) the production of man's body; (3) the production of the woman.
Under the first head there are four points of inquiry:
(1) Whether man's soul was something made, or was of the Divine substance?
(2) Whether, if made, it was created?
(3) Whether it was made by angelic instrumentality?
(4) Whether it was made before the body?
Objection 1: It would seem that the soul was not made, but was God's substance. For it is written (Gn. 2:7): "God formed man of the slime of the earth, and breathed into his face the breath of life, and man was made a living soul." But he who breathes sends forth something of himself. Therefore the soul, whereby man lives, is of the Divine substance.
Objection 2: Further, as above explained (Q[75], A[5]), the soul is a simple form. But a form is an act. Therefore the soul is a pure act; which applies to God alone. Therefore the soul is of God's substance.
Objection 3: Further, things that exist and do differ are the same. But God and the mind exist, and in no way differ, for they could only be differentiated by certain differences, and thus would be composite. Therefore God and the human mind are the same.
On the contrary, Augustine (De Orig. Animae iii, 15) mentions certain opinions which he calls "exceedingly and evidently perverse, and contrary to the Catholic Faith," among which the first is the opinion that "God made the soul not out of nothing, but from Himself."
I answer that, To say that the soul is of the Divine substance involves a manifest improbability. For, as is clear from what has been said (Q[77] , A[2]; Q[79], A[2]; Q[84], A[6]), the human soul is sometimes in a state of potentiality to the act of intelligence ---acquires its knowledge somehow from things---and thus has various powers; all of which are incompatible with the Divine Nature, Which is a pure act---receives nothing from any other---and admits of no variety in itself, as we have proved (Q[3], AA[1],7; Q[9], A[1]).
This error seems to have originated from two statements of the ancients. For those who first began to observe the nature of things, being unable to rise above their imagination, supposed that nothing but bodies existed. Therefore they said that God was a body, which they considered to be the principle of other bodies. And since they held that the soul was of the same nature as that body which they regarded as the first principle, as is stated De Anima i, 2, it followed that the soul was of the nature of God Himself. According to this supposition, also, the Manichaeans, thinking that God was corporeal light, held that the soul was part of that light bound up with the body.
Then a further step in advance was made, and some surmised the existence of something incorporeal, not apart from the body, but the form of a body; so that Varro said, "God is a soul governing the world by movement and reason," as Augustine relates (De Civ. Dei vii, 6 [*The words as quoted are to be found iv. 31.]) So some supposed man's soul to be part of that one soul, as man is a part of the whole world; for they were unable to go so far as to understand the different degrees of spiritual substance, except according to the distinction of bodies.
But, all these theories are impossible, as proved above (Q[3], AA[1],8; and Q[75], A[1]), wherefore it is evidently false that the soul is of the substance of God.
Reply to Objection 1: The term "breathe" is not to be taken in the material sense; but as regards the act of God, to breathe [spirare], is the same as to "make a spirit." Moreover, in the material sense, man by breathing does not send forth anything of his own substance, but an extraneous thing.
Reply to Objection 2: Although the soul is a simple form in its essence, yet it is not its own existence, but is a being by participation, as above explained (Q[75], A[5], ad 4). Therefore it is not a pure act like God.
Reply to Objection 3: That which differs, properly speaking, differs in something; wherefore we seek for difference where we find also resemblance. For this reason things which differ must in some way be compound; since they differ in something, and in something resemble each other. In this sense, although all that differ are diverse, yet all things that are diverse do not differ. For simple things are diverse; yet do not differ from one another by differences which enter into their composition. For instance, a man and a horse differ by the difference of rational and irrational; but we cannot say that these again differ by some further difference.
Objection 1: It would seem that the soul was not produced by creation. For that which has in itself something material is produced from matter. But the soul is in part material, since it is not a pure act. Therefore the soul was made of matter; and hence it was not created.
Objection 2: Further, every actuality of matter is educed from the potentiality of that matter; for since matter is in potentiality to act, any act pre-exists in matter potentially. But the soul is the act of corporeal matter, as is clear from its definition. Therefore the soul is educed from the potentiality of matter.
Objection 3: Further, the soul is a form. Therefore, if the soul is created, all other forms also are created. Thus no forms would come into existence by generation; which is not true.
On the contrary, It is written (Gn. 1:27): "God created man to His own image." But man is like to God in his soul. Therefore the soul was created.
I answer that, The rational soul can be made only by creation; which, however, is not true of other forms. The reason is because, since to be made is the way to existence, a thing must be made in such a way as is suitable to its mode of existence. Now that properly exists which itself has existence; as it were, subsisting in its own existence. Wherefore only substances are properly and truly called beings; whereas an accident has not existence, but something is (modified) by it, and so far is it called a being; for instance, whiteness is called a being, because by it something is white. Hence it is said Metaph. vii, Did. vi, 1 that an accident should be described as "of something rather than as something." The same is to be said of all non-subsistent forms. Therefore, properly speaking, it does not belong to any non-existing form to be made; but such are said to be made through the composite substances being made. On the other hand, the rational soul is a subsistent form, as above explained (Q[75], A[2]). Wherefore it is competent to be and to be made. And since it cannot be made of pre-existing matter---whether corporeal, which would render it a corporeal being---or spiritual, which would involve the transmutation of one spiritual substance into another, we must conclude that it cannot exist except by creation.
Reply to Objection 1: The soul's simple essence is as the material element, while its participated existence is its formal element; which participated existence necessarily co-exists with the soul's essence, because existence naturally follows the form. The same reason holds if the soul is supposed to be composed of some spiritual matter, as some maintain; because the said matter is not in potentiality to another form, as neither is the matter of a celestial body; otherwise the soul would be corruptible. Wherefore the soul cannot in any way be made of pre-existent matter.
Reply to Objection 2: The production of act from the potentiality of matter is nothing else but something becoming actually that previously was in potentiality. But since the rational soul does not depend in its existence on corporeal matter, and is subsistent, and exceeds the capacity of corporeal matter, as we have seen (Q[75], A[2]), it is not educed from the potentiality of matter.
Reply to Objection 3: As we have said, there is no comparison between the rational soul and other forms.
Objection 1: It would seem that the rational soul is not immediately made by God, but by the instrumentality of the angels. For spiritual things have more order than corporeal things. But inferior bodies are produced by means of the superior, as Dionysius says (Div. Nom. iv). Therefore also the inferior spirits, who are the rational souls, are produced by means of the superior spirits, the angels.
Objection 2: Further, the end corresponds to the beginning of things; for God is the beginning and end of all. Therefore the issue of things from their beginning corresponds to the forwarding of them to their end. But "inferior things are forwarded by the higher," as Dionysius says (Eccl. Hier. v); therefore also the inferior are produced into existence by the higher, and souls by angels.
Objection 3: Further, "perfect is that which can produce its like," as is stated Metaph. v. But spiritual substances are much more perfect than corporeal. Therefore, since bodies produce their like in their own species, much more are angels able to produce something specifically inferior to themselves; and such is the rational soul.
On the contrary, It is written (Gn. 2:7) that God Himself "breathed into the face of man the breath of life."
I answer that, Some have held that angels, acting by the power of God, produce rational souls. But this is quite impossible, and is against faith. For it has been proved that the rational soul cannot be produced except by creation. Now, God alone can create; for the first agent alone can act without presupposing the existence of anything; while the second cause always presupposes something derived from the first cause, as above explained (Q[75], A[3]): and every agent, that presupposes something to its act, acts by making a change therein. Therefore everything else acts by producing a change, whereas God alone acts by creation. Since, therefore, the rational soul cannot be produced by a change in matter, it cannot be produced, save immediately by God.
Thus the replies to the objections are clear. For that bodies produce their like or something inferior to themselves, and that the higher things lead forward the inferior---all these things are effected through a certain transmutation.
Objection 1: It would seem that the human soul was made before the body. For the work of creation preceded the work of distinction and adornment, as shown above (Q[66], A[1]; Q[70], A[1]). But the soul was made by creation; whereas the body was made at the end of the work of adornment. Therefore the soul of man was made before the body.
Objection 2: Further, the rational soul has more in common with the angels than with the brute animals. But angels were created before bodies, or at least, at the beginning with corporeal matter; whereas the body of man was formed on the sixth day, when also the animals were made. Therefore the soul of man was created before the body.
Objection 3: Further, the end is proportionate to the beginning. But in the end the soul outlasts the body. Therefore in the beginning it was created before the body.
On the contrary, The proper act is produced in its proper potentiality. Therefore since the soul is the proper act of the body, the soul was produced in the body.
I answer that, Origen (Peri Archon i, 7,8) held that not only the soul of the first man, but also the souls of all men were created at the same time as the angels, before their bodies: because he thought that all spiritual substances, whether souls or angels, are equal in their natural condition, and differ only by merit; so that some of them---namely, the souls of men or of heavenly bodies---are united to bodies while others remain in their different orders entirely free from matter. Of this opinion we have already spoken (Q[47], A[2]); and so we need say nothing about it here.
Augustine, however (Gen. ad lit. vii, 24), says that the soul of the first man was created at the same time as the angels, before the body, for another reason; because he supposes that the body of man, during the work of the six days, was produced, not actually, but only as to some "causal virtues"; which cannot be said of the soul, because neither was it made of any pre-existing corporeal or spiritual matter, nor could it be produced from any created virtue. Therefore it seems that the soul itself, during the work of the six days, when all things were made, was created, together with the angels; and that afterwards, by its own will, was joined to the service of the body. But he does not say this by way of assertion; as his words prove. For he says (Gen. ad lit. vii, 29): "We may believe, if neither Scripture nor reason forbid, that man was made on the sixth day, in the sense that his body was created as to its causal virtue in the elements of the world, but that the soul was already created."
Now this could be upheld by those who hold that the soul has of itself a complete species and nature, and that it is not united to the body as its form, but as its administrator. But if the soul is united to the body as its form, and is naturally a part of human nature, the above supposition is quite impossible. For it is clear that God made the first things in their perfect natural state, as their species required. Now the soul, as a part of human nature, has its natural perfection only as united to the body. Therefore it would have been unfitting for the soul to be created without the body.
Therefore, if we admit the opinion of Augustine about the work of the six days (Q[74], A[2]), we may say that the human soul preceded in the work of the six days by a certain generic similitude, so far as it has intellectual nature in common with the angels; but was itself created at the same time as the body. According to the other saints, both the body and soul of the first man were produced in the work of the six days.
Reply to Objection 1: If the soul by its nature were a complete species, so that it might be created as to itself, this reason would prove that the soul was created by itself in the beginning. But as the soul is naturally the form of the body, it was necessarily created, not separately, but in the body.
Reply to Objection 2: The same observation applies to the second objection. For if the soul had a species of itself it would have something still more in common with the angels. But, as the form of the body, it belongs to the animal genus, as a formal principle.
Reply to Objection 3: That the soul remains after the body, is due to a defect of the body, namely, death. Which defect was not due when the soul was first created.