First Act is the universal principle of all acts;
because It is infinite, virtually "precontaining all things," as
Dionysius says (Div. Nom. v). Wherefore things participate of It not
as a part of themselves, but by diffusion of Its processions. Now as
potentiality is receptive of act, it must be proportionate to act.
But the acts received which proceed from the First Infinite Act, and
are participations thereof, are diverse, so that there cannot be one
potentiality which receives all acts, as there is one act, from which
all participated acts are derived; for then the receptive
potentiality would equal the active potentiality of the First Act.
Now the receptive potentiality in the intellectual soul is other than
the receptive potentiality of first matter, as appears from the
diversity of the things received by each. For primary matter receives
individual forms; whereas the intelligence receives absolute forms.
Hence the existence of such a potentiality in the intellectual soul
does not prove that the soul is composed of matter and form.

Reply Obj. 2: To be a subject and to be changed belong to matter by
reason of its being in potentiality. As, therefore, the potentiality
of the intelligence is one thing and the potentiality of primary
matter another, so in each is there a different reason of subjection
and change. For the intelligence is subject to knowledge, and is
changed from ignorance to knowledge, by reason of its being in
potentiality with regard to the intelligible species.

Reply Obj. 3: The form causes matter to be, and so does the agent;
wherefore the agent causes matter to be, so far as it actualizes it
by transmuting it to the act of a form. A subsistent form, however,
does not owe its existence to some formal principle, nor has it a
cause transmuting it from potentiality to act. So after the words
quoted above, the Philosopher concludes, that in things composed of
matter and form "there is no other cause but that which moves from
potentiality to act; while whatsoever things have no matter are
simply beings at once." [*The Leonine edition has, "simpliciter sunt
quod vere entia aliquid." The Parma edition of St. Thomas's
Commentary on Aristotle has, "statim per se unum quiddam est . . .
et ens quiddam."]

Reply Obj. 4: Everything participated is compared to the participator
as its act. But whatever created form be supposed to subsist "per
se," must have existence by participation; for "even life," or
a