And this is contrary to the concept of generation in the strict sense. Fourthly, because that which is caused by God is either something subsistent: and thus it must needs be essentially distinct from the preexisting form, which was nonsubsistent; and we shall then come back to the opinion of those who held the existence of several souls in the body. Or else it would not be subsistent, but a perfection of the preexisting soul: and then the intellective soul would perish with the body: and this is unacceptable . . . We must therefore say that, when a more perfect form supervenes, the previous form is corrupted, since the generation of one being always implies the corruption of another being, both in men and in animals: and this occurs in such a way that the subsequent form has all the perfections of the previous form, and something more. In this way, through various generations and corruptions, we arrive at the ultimate substantial form, both in man as well as in other animals. And this can also be seen in animals generated from putrefaction. We must conclude therefore that the intellective soul is created by God at the end of human generation, with the disappearance of the preexisting forms, and that this soul is both sensitive and nutritive.
The rational soul, at the moment in which it is created, therefore formats, so to speak, the two souls—vegetative and sensitive—and recharges them as an integral part of the rational soul.
In the Summa contra Gentiles (book 2, part 89, reply to argument 11) it is repeated that there is an order, a grading in the generative process, “due to intermediate forms in which the fetus is equipped from the beginning until its final form.”1
At what point in the formation of the fetus is it infused with that intellective soul that makes it a human person in all respects? Traditional doctrine was very cautious on this point, and it was generally said to be forty days. Thomas says only that the soul is created when the body of the fetus is ready to receive it.
In the Summa (part 3, question 33, article 2) Thomas asks whether Christ’s soul was created at the same time as his body. Note that, since Christ’s conception did not take place through the transfer of semen but through the grace of the Holy Spirit, it should not be surprising if in such a case God had created the fetus and the rational soul at the same time. But even Christ, as Man and God, must follow human laws: “The beginning of the infusion of the soul may be considered in two ways. First, in regard to the disposition of the body. In this sense the soul of Christ, like the soul of other men, was infused when his body was formed. Secondly, in relation to time alone. And thus, because Christ’s body was perfectly formed in a shorter space of time than that of other men, so he also received his soul before them.”
But the problem here is not so much when a fetus becomes a human being, but whether the embryo is already a human being. And Thomas is very clear on this point, as we have seen. And even though the Supplement to the Summa is not written by him but probably by his disciple Reginald of Piperno, it is interesting to read question 80, article 4. The problem is whether, upon the resurrection of bodies, all that has contributed to the growth of these bodies is resurrected. Several apparently grotesque questions arise from this. Food is transformed into substance of a human nature; humans eat the flesh of oxen: therefore, if what was the substance of a human nature is resurrected, will the flesh of oxen also be resurrected? It is impossible for one and the same thing to be resurrected in different men. And yet it is possible for something to have belonged in substance to different men, as in the case of the cannibal who eats human flesh, which is transformed into his own substance. Who then is resurrected? The eater or the one who is eaten?
Question 80 is answered in a complex and tortuous manner and seems not to side with any of the various opinions. But what interests us is that at the end of the discussion it is said that natural beings are what they are, not in terms of matter, but in their form. Therefore if the matter that first had the form of beef is then resurrected in man in the form of human flesh, it will certainly not do so as the flesh of an ox but as that of a human being. Otherwise it would mean that the mud from which Adam’s body was created would also be resurrected. As for the question of cannibalism, according to one view, the flesh eaten never truly becomes part of the human nature of the person eating it, but remains that of the person who has been eaten. Such flesh will therefore be resurrected in the latter and not in the former.
But the specific point that interests us is that, according to this question, embryos will not take part in the resurrection of the flesh unless they have first been animated by the rational soul.
Now it would be infantile to ask Thomas to absolve those who carry out an abortion within a given period of time, and probably he didn’t even think of the moral implications of his reasoning, which today we would describe as being purely scientific. It is curious, however, that the church, which is always quoting the teachings of Thomas Aquinas, has decided on this point to distance itself tacitly from his position.
Something similar has happened with the theory of evolution, with which the church came to terms a long time ago—it was sufficient to interpret the six days of the creation figuratively, as the fathers of the church have always done, and in this way there are no biblical objections to an evolutionary view. Indeed, the book of Genesis is an extremely Darwinian text because it tells us that the creation took place in stages from the least complex to the most complex, from mineral to vegetable, animal, and human.
In the beginning God created the heaven and the earth . . . And God said, Let there be light: and there was light. And God saw the light, that it was good: and God divided the light from the darkness. And God called the light Day, and the darkness he called Night . . . And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament . . . And God said, Let the waters under the heaven be gathered together unto one place, and let the dry land appear: and it was so. And God called the dry land Earth; and the gathering together of the waters called he Seas . . .
And God said, Let the earth bring forth grass, the herb yielding seed, and the fruit tree yielding fruit after his kind . . . And God made two great lights; the greater light to rule the day, and the lesser light to rule the night: he made the stars also . . . And God said, Let the waters bring forth abundantly the moving creature that hath life, and fowl that may fly above the earth in the open firmament of heaven. And God created great whales, and every living creature that moveth, which the waters brought forth abundantly . . . And God said, Let the earth bring forth the living creature after his kind, cattle, and creeping thing, and beast of the earth after his kind . . . And God said, Let us make man in our image, after our likeness . . . And the Lord God formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living soul. (Genesis 1:1–27 and 2:7)
The choice of a battle against evolution and in defense of life, back as far as the embryo, seems rather more in line with the positions of Protestant fundamentalism.
But, as I have said, this lecture was not intended to enter into present disputes but only to explain the thinking of Thomas Aquinas, with which the church of Rome can do as it pleases. I therefore propose to stop here, leaving these documents for the consideration of my listeners.
[Lecture given on November 25, 2008, in Bologna, at the Scuola Superiore di Studi Umanistici, during a conference on the ethics of research, later published in the proceedings: Etica della ricerca medica e identità culturale europea, edited by Francesco Galofaro (Bologna: CLUEB, 2009).]
The end
