No Embryos in Paradise, Umberto Eco
No Embryos in Paradise
IT IS NOT MY INTENTION in this lecture to support philosophical, theological, and bioethical positions on problems relating to abortion, stem cells, embryos, and the so-called right to life. My approach is purely historical and seeks to examine what Saint Thomas Aquinas thought about such matters. At most, the fact that the church of today thinks differently makes my reconstruction particularly curious.
The debate is extremely old, dating back to Origen, who claimed that God created human souls that had existed from the very beginning. His view was immediately challenged, not least in the light of the words of Genesis (2:7) that “the Lord formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living soul.” In the Bible, therefore, God creates the body, and then breathes a soul into it, and this doctrine, which became the church’s official doctrine, is called creationism. But this position posed problems so far as the transmission of original sin. If the soul is not transmitted by the parents, why are babies not free from original sin, so that they have to be baptized? Thus Tertullian (in De anima) claimed that the soul of the parent is “translated” from father to son through his semen. But traducianism was immediately judged to be heretical, since it presumed that the soul had a material origin.
The person who found himself in difficulty was Saint Augustine: he had to reckon with the Pelagians, who denied the transmission of original sin. He therefore supported the creationist doctrine (against bodily traducianism) while admitting, at the same time, a sort of spiritual traducianism. But all commentators take the view that his position is rather convoluted. Augustine was tempted to accept traducianism, but finally, in epistle 190, he admits to being uncertain and observes that the holy scriptures support neither traducianism nor creationism. We can also see how he wavers between the two positions in De genesi ad litteram.
Saint Thomas Aquinas was decidedly creationist, and resolved the question of original guilt in a most elegant way. Original sin is transmitted by semen like a natural infection (Summa Theologica, second part of part 1, question 81, article 1, reply to objections 1 and 2), but this has nothing to do with the transmission of the rational soul:
It is said that the child will not carry the iniquity of the father in the sense that he will not be punished for the sin of the father, unless he is a party to the blame. But this is what happens in our case: in fact original sin is transmitted from father to child through procreation, in the same way that actual sin is transmitted by imitation . . . Yet the soul is not transmitted, because the power of the semen is not able to produce a rational soul, nevertheless the semen cooperates as an instrument. Thus, through the power of the semen, human nature is transmitted from parents to children, and the corruption of human nature with it. In fact, he who is born becomes a party to the guilt of his parent; because by force of procreation, he inherits his nature from him.
If the soul is not transmitted with the semen, then when is it introduced into the fetus? Remember that, according to Thomas, plants have a vegetative soul, which in animals is supplanted by the sensitive soul, whereas in human beings these two functions are supplanted by the rational soul, which is what produces intelligent man—and what, moreover, makes a person, insofar as the person was, by ancient tradition, an “individual substance of a rational nature.” It is the rational soul that will endure the corruption of the body and will be sent to damnation or to eternal glory—this is what makes man what he is and distinguishes him from an animal or a plant.
Thomas has a very biological view about the formation of the fetus: God introduces the soul only when the fetus acquires, stage by stage, first a vegetative soul and then a sensitive soul. Only at that point, in a body already formed, is the rational soul created (Summa, part 1, question 90).
Therefore the embryo has only a sensitive soul (Summa, part 1, question 76, article 3):
The philosopher teaches that the embryo is first animal and then man. But this cannot be so, if the essence of the sensitive soul and the intellective soul are identical: since an animal is so made from its sensitive soul, man however is so constituted by that intellective soul. The essence of the sensitive soul and the intellective soul is therefore not the same . . . We must therefore conclude that in man there exists one soul, which is sensitive, intellective, and vegetative. This can be easily explained if we consider the differences of species and forms.
For we observe that the species and forms differ from one another according to various grades of perfection: thus in the order of nature animate beings are more perfect than inanimate beings, animals more than plants; men more than beasts; and in each of these kinds there are various grades. For this reason Aristotle . . . compares the various animals to [geometrical] figures, one of which contains another so that, for example, the pentagon contains and transcends the rectangle. In a similar way, the intellective soul contains virtually all that belongs to the sensitive soul of animals and the vegetative soul of plants. Therefore, in the same way that the surface of the pentagon is not a rectangle because it has one figure different to that of the rectangle, so that the figure of the rectangle being contained in the pentagon would be superfluous, likewise Socrates is not a man by one soul and animal by another, but he is both man and animal by the same soul . . . the embryo has first of all a soul that is merely sensitive, and when eliminated, it is supplanted by a more perfect soul, which is both sensitive and intellective.
In the Summa (part 1, question 118, article 1, reply to objection 4) it is said that the sensitive soul is transmitted with the semen:
In perfect animals, generated by coitus, the active force, according to the Philosopher, is in the semen of the male: but the fetal matter is provided by the female. This vegetative soul exists in this material from the very beginning, not at a later instance but in the initial act, like the sensitive soul exists in one who sleeps. But when it begins to attract nourishment, then it actually operates. This matter is therefore transmuted by the power enclosed in the semen of the male, until it becomes the sensitive soul: not in the sense that the power present in the semen passes to become the sensitive soul; because in such a case, the generator and the generated would be the same thing; and the process would be more like nourishment and growth than generation, as the Philosopher observes. But when, by the power of the active principle in the semen, the sensitive soul is produced in the principal structure of the generated being, then the sensitive soul of the offspring begins to work toward the perfection of its own body, through the acts of nutrition and development. The active power of the semen ceases to exist as soon as the semen is dissolved and the spirit enclosed within it has vanished. Nor is there anything strange in this fact, because this force is not a principal agent, but instrumental; and the movement of the instrument ceases once the effect is produced in the being.
And in the Summa (part 1, question 118, article 2, reply) Thomas denies that the power of the semen can produce the intellective element, and therefore that a soul exists at the moment of conception. Since the intellective soul is an immaterial substance, it cannot be caused through procreation, but only through creation by God. Anyone admitting that the intellective soul is transmitted by semen would also have to admit that it does not exist alone and, as a result, that it is corrupted upon the corruption of the body.
In the same question (ad secundum) Thomas also denies that to the vegetative soul, present at the beginning, there is added another, namely, the sensitive soul; and after this another still, that is, the intellective soul. In this way man would have three souls, so that one would be in the power of another. And he denies that the same soul, which at the beginning was merely vegetative, then develops, by action of the power of the semen, until it also becomes sensitive; and finally develops until it becomes an intellective soul, not just by the active power of the semen, but through the power of a superior agent, namely God, who would come from outside to illuminate it:
But this does not hold. First, because no substantial form is susceptible of more or less; but the addition of greater perfection changes the species, just as the addition of unity changes the species of number. Now it is not possible for the same identical form to belong to different species. Secondly, because it would follow from this that the generation of an animal would be a continuous movement, proceeding from the imperfect to the perfect, as happens in alteration. Thirdly, because the generation of a man or an animal would no longer be generation in the strict sense, because their subject would already be taking place. For if the vegetative soul is
