summa-contra-gentiles

CHAPTERS LXXX AND LXXXI 227
which clearly cannot remain after the body, since they are
acts of certain organs of the body, and operate through
those organs. Hence Aristotle says that the soul does not
understand ivithout phantasms,^ and that it understands
nothing ivithout the passive intellect,' which he calls the
cogitative power, and which is corruptible. For this reason
he says (i
De AnimaY that man's act of understanding is
corrupted when something within him is corrupted, namely
the phantasm or the passive intellect. And it is stated in
3 De Anima* that after death we do not remember what we
knew in life. It is
accordingly evident that no operation of
the soul can remain after death. Therefore neither does
its substance remain, since no substance can be without
operation.
^
Now, since these arguments lead to a false conclusion,
as was shown above,* we must endeavour to answer them.
And, in the first it
place, must be observed that whatever
things have to be adapted and proportionate to one another,
are together multiplied or unified, each by
its own cause.
Wherefore if the being of one depends on the other, its
unity or multiplicity depends also thereon ;
otherwise it
depends on some other extrinsic cause. Now form and
matter need always to be mutually proportionate and
naturally adapted, so to speak, because the proper act is
produced in its proper matter. Consequently matter and
form must always agree in point of multitude and unity.
Hence if the being of the form depend on matter, its multiplication,
as also its unity, depends on matter. But if not,
the form must needs be multiplied according to the multiplication
of the matter, that is together with matter, and in
proportion thereto :
yet not so that the unity or multiplicity
of the very form depend on matter. Now it has been shown^
that the human soul is a form independent of matter as to
its being. Wherefore it follows that souls are indeed multiplied
according as bodies are multiplied, and yet the multiplication
of bodies is not the cause of the multiplication of
souls. Therefore it does not follow that the plurality of
^ 3 De Anima vii. 3.
* Ibid., v. 2.
' iv. 14. * v 2
'
Ch. Ixxxi. • Ch. Ixxii. '
Ch. Ix\-iii.