Article 12 — Whether the sensitive or vegetative souls are in the seed when it is separated

The twelfth point of inquiry is whether the sensitive or vegetative souls are in the seed when this is separated. (Parallel texts: ST I.118.1, ad 3, ad 4; In II Sent. 18.2.1.)

Obj. 1: And it seems that this is so. For Gregory of Nyssa says that it is reprehensible to hold either opinion, whether of those who foolishly assert a previous existence of souls in a certain state and order becoming to them, or of those who maintain that our souls are created after our bodies. (Gregory of Nyssa, On the Making of Man 29 (PL 67:396).) Now, if the soul was not in the seed from its beginning, it must come to be after the body. Therefore, the soul was in the seed from the beginning.

Obj. 2: If the sensitive soul was not in the seed from the beginning, just as the rational soul was not, the same account will belong to the sensitive and the rational souls. Now, the rational soul is created. Therefore, the sensitive soul is also created, although we have proved the contrary to be the case.

Obj. 3: The Philosopher says, in On Animals, that the power residing in the seed is like a son going forth from his father’s house. (Aristotle, On the Generation of Animals 2.4, 740a5–10.) Now, the son is of the same species as his father. Therefore, the power in the seed is of the same species as the sensitive soul from which it derives.

Obj. 4: The Philosopher says, in On Animals, that this same power is like an art that, were it in the matter, would work toward the perfection of the artwork. (Aristotle, On the Generation of Animals 2.4, 740b24–31.) Now, the species of the artwork is within the art. Therefore, the species of the sensitive soul produced through the seed is in that power of the seed.

Obj. 5: The separation of the seed is natural, whereas the separation of a segmented animal is contrary to nature. Now, according to the Philosopher, the soul is in the separated part of a segmented animal. Much more, then, is it in the seed when separated.

Obj. 6: In On Animals, the Philosopher says that, in the generation of an animal, the male provides the soul. (Aristotle, On the Generation of Animals 2.4, 738b20, 740b24.) Now, nothing issues from the father except the seed. Therefore, the soul is in the seed.

Obj. 7: An accident is not transmitted unless its subject be transmitted. Now, certain diseases are transmitted from parents to their children, such as leprosy, gout, and so on. Consequently, the subject of these diseases is also transmitted, which subject cannot be soulless. Therefore, the soul is in the seed from the beginning.

Obj. 8: Hippocrates says that generation is prevented by the excision of a vein near the ears. (Hippocrates, Places in Man 3. This is Hippocrates of Kos, known as the “Father of Medicine,” who lived ca. 460–375 BC.) Now, this would not be unless the seed were taken from the whole body, as though it were an action existing before. Since, then, the soul is in whatever is actually part of an animal, it would seem that the soul is in the seed from the beginning.

Obj. 9: He also says that a certain horse on account of too frequent coition was found to have no brain. But this would not be unless the seed were taken from that which is an actual part. Therefore, the same conclusion follows.

Obj. 10: The superfluous is not part of the substance of a thing. Accordingly, if the seed is superfluous, it will not belong to the substance of the generator, and thus the child that results from the seed will not be of his father’s substance, which is incongruous. Therefore, the seed is part of the generator’s substance, and consequently, the soul is therein actually.

Obj. 11: That which has no soul is inanimate. If, then, the seed is without soul, it will be inanimate. Consequently, an inanimate body will be transformed and become animate, and this would seem incongruous. Therefore, the soul is in the seed from the beginning.

On the contrary (1), the Philosopher says that the seed and the fruit are in a sort of potency toward the soul but are without soul. (Aristotle, On the Soul 2.1, 412b25–413a4; 2.3, 736b7–12.)

Furthermore (2), it would seem impossible for the seed to have soul from the first except in two ways: either by the transmission of the generator’s entire soul into the seed, or by the transmission of part thereof. Now, either of these seems to be incongruous, since from the former it would follow that the soul does not remain in the father, and from the latter, that not the entire soul remains. Therefore, the soul is not in the seed from the beginning.

I answer that some held the opinion that the soul is in the seed from the moment of its separation, so that they would have it that, just as body is divided from a body, so too simultaneously is soul propagated by a soul, such that right away with the small particle of the body there would also be a soul there.

But this opinion does not seem to be true, because (as the Philosopher proves in On Animals) the seed is not separated from an actual part, but from the surplus remaining after the final digestion, what was not assimilated with a final assimilation. (Aristotle, On the Generation of Animals 1.18–19, 725a11–28, 726a26–727b34.) Now, no part of the body is actually perfected by the soul unless it be finally assimilated; therefore, the seed, before being separated, was not yet perfected by the soul, such that the soul would be its form. Nonetheless, there was in the seed a certain power in respect of which, by the action of the soul, it was already altered and brought to the disposition right before the final assimilation; whence even after separation, soul is not there, but rather a certain power of soul. For this reason, the Philosopher says, in On Animals, that in the seed there is a power of the principle of the soul. (Aristotle, On the Generation of Animals 2.3, 736b9–12, 736b35, 737a30–34.)

Moreover, if the soul were in the seed from the beginning, it would be either there in its species as a soul actually, or not, but instead as a certain power that would later be transformed into a soul. The former cannot be the case; for, since the soul is the act of an organized body, (Aristotle, On the Soul 2.1, 412b5.) the body is not receptive of the soul before it is in any sort of organization. Moreover, it would follow that all that it brings about in seeds is a certain disposition of the matter, and consequently, there would be no generation, since generation does not follow but precedes the substantial form—unless one were to say that besides the soul there is another substantial form of the body, the result being that the soul would not be substantially united to the body, seeing that it would be added to the body after the latter had already been established as this thing by the other form.

It would follow, moreover, that the generation of a living thing would not be a generation but a certain separation, just as timber cut off from timber is actually timber.

The second alternative is also impossible, since in that case, it would follow that the substantial form arises not at once but by degrees in the matter, such that there would be movement in substance, as there is in quantity and quality, which is contrary to the teaching of the Philosopher. (Aristotle, Physics 5.2, 225b10, 226a24–32.) It would also follow that substantial forms are subject to increase and decrease, which is impossible. It follows, then, that there is not a soul in the seed, but a certain power of the soul that acts toward the production of a soul, itself derived from the soul.

Reply Obj. 1: The body of a living thing, for example, that of a lion or an olive, is not a soul but rather is the seed of the body only before the soul, and before the power that acts toward a soul. For the proportion of the seed to such a power is the same as that of a body toward the soul.

Reply Obj. 2: There is this difference between the rational and other souls, that the rational soul is not from the power of the seed, as the other souls are, although no soul is in the seed from the beginning.

Reply Obj. 3: This power is likened to a son going forth from his father’s house not as regards the completion of the species, but as regards the acquisition of things that each of them lacks for a certain completion. For a first perfection is often made manifest through a likeness of second perfection.

Reply Obj. 4: The likeness between this power and art consists in the fact that just as the artwork pre-exists within the art as in an active power, so too are living things that are to be generated within the formative power.

Reply Obj. 5: The cutting apart of a segmented animal is violent and against nature because the part cut away was actually a part and perfected by the soul; whence by the cutting of the matter the soul remains in either part, which soul was actually one in the whole body and potentially several. This happens because in animals of this kind the whole body is composed of almost homogeneous parts, for their souls, being of a lower degree of perfection than others, require but little diversity of organs. Therefore, when a part is severed, it can be receptive to the soul as having sufficient organs for receiving soul, as happens in the case of other like bodies such as wood, stone, water, and air. The Philosopher proves from this, in On Animals, that the seed was not actually a part before its separation, for the reason that its separation would not have been natural but a sort of corruption; (Aristotle, On the Generation of Animals 1.18, 723b9–16, 724b30.) therefore, it does not follow that the soul remains in the seed itself after its separation.

Reply Obj. 6: The male is said to provide the soul inasmuch as the seed of the male contains a power that acts for the sake of the soul.

Reply Obj. 7: The diseases mentioned in the objection are not transmitted together with the seed as though they were actually in the seed, but because their principles are in the seed through a certain indisposition of the seed.

Reply Obj. 8: Seeing that the semen is a certain surplus, it has certain channels proper to it, like other superfluities, and if these outlets be cut off, generation is prevented, and not because something of what was an actual part of the body has been destroyed.

Reply Obj. 9: It is the same with the immoderate emission of seed as with the immoderate discharge of other superfluities, which destroys what has already been converted, a destruction that is violent and unnatural. But things that happen contrary to nature must not be ascribed to the action of nature.

Reply Obj. 10: The seed is a surplus in the sense that, although it is not actually a part of the father’s substance, it is potentially the whole thereof, and for this reason, the child is said to be of his father’s substance.

Reply Obj. 11: Although the seed is not actually animate, it is animate by power; whence it is not simply speaking inanimate.