n of
Christ's Body?

Objection 1: It would seem that the Blessed Virgin cooperated
actively in the conception of Christ's body. For Damascene says (De
Fide Orth. iii) that "the Holy Ghost came upon the Virgin, purifying
her, and bestowing on her the power to receive and to bring forth the
Word of God." But she had from nature the passive power of
generation, like any other woman. Therefore He bestowed on her an
active power of generation. And thus she cooperated actively in
Christ's conception.

Obj. 2: Further, all the powers of the vegetative soul are active, as
the Commentator says (De Anima ii). But the generative power, in both
man and woman, belongs to the vegetative soul. Therefore, both in man
and woman, it cooperates actively in the conception of the child.

Obj. 3: Further, in the conception of a child the woman supplies the
matter from which the child's body is naturally formed. But nature is
an intrinsic principle of movement. Therefore it seems that in the
very matter supplied by the Blessed Virgin there was an active
principle.

_On the contrary,_ The active principle in generation is called the
"seminal virtue." But, as Augustine says (Gen. ad lit. x), Christ's
body "was taken from the Virgin, only as to corporeal matter, by the
Divine power of conception and formation, but not by any human
seminal virtue." Therefore the Blessed Virgin did not cooperate
actively in, the conception of Christ's body.

_I answer that,_ Some say that the Blessed Virgin cooperated actively
in Christ's conception, both by natural and by a supernatural power.
By natural power, because they hold that in all natural matter there
is an active principle; otherwise they believe that there would be no
such thing as natural transformation. But in this they are deceived.
Because a transformation is said to be natural by reason not only of
an active but also of a passive intrinsic principle: for the
Philosopher says expressly (Phys. viii) that in heavy and light
things there is a passive, and not an active, principle of natural
movement. Nor is it possible for matter to be active in its own
formation, since it is not in act. Nor, again, is it possible for
anything to put itself in motion except it be divided into two parts,
one being the mover, the other being moved: which happens in animate
things only, as is proved _Phys._ viii.

By a supernatural power, because they say that the mother requires
not only to supply the matter,