Now, this further point is also clear: In the very beginning of conception the rational soul was united to the body.
 The Word of God, of course, assumed the body through the soul’s mediation, for the body of a man is not more subject to assumption by God than other bodies except because of the rational soul. The Word of God, then, did not assume the body without the rational soul. Therefore, since the Word of God assumed the body in the very beginning of conception, necessarily the rational soul was united to the body in the very beginning of conception.
 Moreover, one who grants what is posterior in a generation must grant also that which is prior in the order of generation. But the posterior in a generation is that which is most perfect. But the most perfect is the generated individual, and this in human generation is an hypostasis or person, and it is toward constituting this that the body and soul are ordered. Granted, then, a personality of the man generated, there must needs exist a body and a rational soul. But the personality of the man Christ is not different from the personality of God’s Word. But the Word of God united a human body to Himself in the very conception. Therefore, the personality of that man was there. Therefore, the rational soul must also have been there.
 It would also have been awkward if the Word, the fount and origin of all perfections and forms, were united to a thing. not formed, which still was lacking the perfection of nature. Now, anything corporeal that comes into being is, before its animation, formless and still lacking the perfection of nature. It was, therefore, not fitting for the Word of God to be united to a body not yet animated. Thus, from the moment of conception that soul had to be united to the body.
 Hence, this point too, is clear: The body assumed in the moment of conception was a formed body, if the assumption of something not formed was improper for the Word. But the soul demands its proper matter, just as any other natural form does. But the proper matter of the soul is the organized body, for a soul is “the entelechy of a natural organic body having life potentially.” If, then, the soul from the beginning of the conception was united to the body (this has been shown), the body from the beginning of the conception was of necessity organized and formed. And even the organization of the body precedes in the order of generation the introduction of the rational soul. Here, again, if one grants what is posterior, he must grant what is prior.
 But there is no reason why a quantitative increase up to the due measure should not follow on the body’s being animated. And so, regarding the conception of the man assumed, one should hold that in the very beginning of conception the body was organized and formed, but had not yet its due quantity.
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