was
non-subsistent; and we shall then come back to the opinion of those
who held the existence of several souls in the body--or else it is
not subsistent, but a perfection of the pre-existing soul: and from
this it follows of necessity that the intellectual soul perishes with
the body, which cannot be admitted.

There is again another explanation, according to those who held that
all men have but one intellect in common: but this has been disproved
above (Q. 76, A. 2).

We must therefore say that since the generation of one thing is the
corruption of another, it follows of necessity that both in men and
in other animals, when a more perfect form supervenes the previous
form is corrupted: yet so that the supervening form contains the
perfection of the previous form, and something in addition. It is in
this way that through many generations and corruptions we arrive at
the ultimate substantial form, both in man and other animals. This
indeed is apparent to the senses in animals generated from
putrefaction. We conclude therefore that the intellectual soul is
created by God at the end of human generation, and this soul is at
the same time sensitive and nutritive, the pre-existing forms being
corrupted.

Reply Obj. 3: This argument holds in the case of diverse agents not
ordered to one another. But where there are many agents ordered to
one another, nothing hinders the power of the higher agent from
reaching to the ultimate form; while the powers of the inferior
agents extend only to some disposition of matter: thus in the
generation of an animal, the seminal power disposes the matter, but
the power of the soul gives the form. Now it is manifest from what
has been said above (Q. 105, A. 5; Q. 110, A. 1) that the whole of
corporeal nature acts as the instrument of a spiritual power,
especially of God. Therefore nothing hinders the formation of the
body from being due to a corporeal power, while the intellectual soul
is from God alone.

Reply Obj. 4: Man begets his like, forasmuch as by his seminal power
the matter is disposed for the reception of a certain species of form.

Reply Obj. 5: In the action of the adulterer, what is of nature is
good; in this God concurs. But what there is of inordinate lust is
evil; in this God does not concur.
_______________________

THIRD ARTICLE [I, Q. 118, Art. 3]

Whether Human Souls Were Created Together at the Beginning of the
World?

Objection 1: It would seem that human soul