Summa contra Gentiles2.85 Chapter LXXXV. That the soul is not made of God*s substance

From the foregoing it is clear that the soul is not of God’s substance.

For it has been shown above that the divine substance is eternal, and that nothing pertaining thereto begins anew. Whereas human souls did not exist before bodies, as we have proved. Therefore the soul cannot be of the divine substance.

Moreover. It was shown above that God cannot be the form of anything. Whereas the soul is the form of the body, as we have proved. Therefore it is not of the divine substance.

Further. Everything from which something is made is in potentiality to that which is thus made from it. But God’s substance is not in potentiality to anything: for it is pure act, as we proved above. Therefore it is impossible that the soul or any other thing whatsoever be made from God’s substance.

Again. That from which something is made is changed in some way. But God is utterly unchangeable, as we proved above. Therefore it is impossible for anything to be made from Him.

Moreover. The soul shows evident signs of variation in knowledge and virtue, and their opposites: whereas in God there is no variation whatever, neither per se, nor accidental.

Again. It was shown above that God is pure act, wherein there is no potentiality: whereas in the human soul we find both potentiality and act; for it contains the possible intellect which is in potentiality to all that is intelligible, besides the active intellect, as shown above. Therefore the human soul is not from the divine nature.

Again. Since the divine substance is altogether indivisible, the soul cannot be part thereof, but only the whole. Now the divine substance cannot possibly be but one, as we showed above. It follows, therefore, that there would be for all men only one soul as regards the intellect: and this has been refuted above. Therefore the soul is not from the divine substance.

This opinion arose apparently from a triple source. For some maintained that no substance is incorporeal. Consequently they asserted that God is the most noble body, whether this be air, fire, or any other thing that they considered to be a principle, and they affirmed that the soul was of the nature of this body. For they all ascribed to the soul, whatever they considered to be a principle, as Aristotle says (i De Anuna) A and thus it followed that the soul is from the divine substance. From this root sprang the opinion of Manes who thought that God is a bright body extending through infinite space, whereof, said he, the human soul is a fragment.

But this opinion was refuted above, both because we proved that God is not a body and because we have shown that neither the human soul nor any intellectual substance is a body.

Some have maintained that for all men there is but one intellect, whether active only, or both active and possible, as stated above. And since the ancients asserted that every separate substance is God, it followed that our soul, namely the intellect whereby we understand, is of the divine nature. Wherefore even nowadays certain adherents to the Christian faith, who hold that the active intellect is a separate being, say expressly that the active intellect is God.

But this opinion about the unity of our active intellect was disproved above.

Possibly also, this opinion may have arisen from the very likeness of our soul to God. For it is on account of man’s soul that intelligence, which is esteemed most proper to God, is found to be befitting to no substance in this lower world, save man alone. Hence it might seem that the soul was allied to the divine nature: and especially so to those men who were convinced of the human soul’s immortality.

Moreover this would seem to be confirmed by the fact that after it had been said (Gen. i.): Let Us make man to Our image and likeness, it is added God formed man of the slime of the earth; and breathed into his face the breath of life. From which text some wished to conclude that the soul is of the divine nature: since he who breathes into another’s face, puts forth into another the identical thing which was in himself. And so Scripture would seem to imply that God put into man something divine in order to give him life.

But the aforesaid likeness does not prove that man is a part of the divine substance: for in understanding he suffers from manifold defects, which cannot be said of God. Wherefore this likeness indicates an imperfect image rather than consubstantiality. In fact Scripture indicates this when it says that man was made to God’s image. Hence the aforesaid breathing shows that life came forth from God into man by way of a certain likeness, and not according to identity of substance. For which reason also the spirit of life is stated to have been breathed into his face: because, since the organs of several senses are situate in this part of the body, the signs of life are more evidenced in the face. Accordingly God is said to have breathed the spirit into man’s face, because He gave man the spirit of life, but not by parting it from His own substance. For he who breathes the breath of his body into the face of someone, whence the metaphor is apparently taken, blows into his face the air, but does not send forth part of his substance into him.