1. Exposition of the Opinion

26. Now if another opinion be held [GalenGalen, On the Use of the Parts of the Human Body 14, “Nature has thought out a way to provide a double principle of generation for fetuses, that one of them indeed should be male and the other female;” “The woman herself has all the parts that the male has; but if she has some of them smaller and others larger, the art of nature is here too to be admired, that it did not - even in women - make anything less that ought to be more, nor again anything more that was fittingly less;” “It is sufficient enough to reckon that the male’s seed provides the principle of motion and that the women’s seed confers something on it for the generation of the animal.” William of Ware Sentences 3 q.13, “Others say the opposite, and this is the opinion of Galen, that both the man and the woman cooperate in this formation, but the chief part of the action is on the part of the man and the less chief on the part of the woman.” ⁴⁷], that that any mother is, along with the father, an active cause with respect to the formation of the offspring’s body, although a less principal and a secondary cause and making with the father one total cause - then to save how Mary was mother seems more difficult than when positing the first opinion [n.16]; for it is plain that she ministered the matter, even the whole matter, for Christ’s body, but it is not as plain how she could have cooperated with the Holy Spirit in the forming of the body.

27. Answer to this is made as follows [Bonaventure], that she ministered a matter that had an active force in it, but the force did not have any action because its action was anticipated by the Holy Spirit, who suddenly formed the body from the matter ministered to him; the Virgin then was mother (holding this opinion about a mother’s action) because of the fact she provided the matter and - as far as concerns her part - she had wherewith to act but another stronger agent [sc. the Holy Spirit] prevented her power in the acting. An example is given: fertility was given to Aaron’s rod [Numbers 17.6-8] by which it was able to have actively produced flowers and fruits successively, but it did not produce them because the fertility was prevented by the divine power suddenly producing them.