Do not quail. I am sure in the new heavens and earth, God will allow new quail, as well as new cats and dogs.
1 This truth [the title] can be clearly inferred from what has been already said.
2 For we demonstrated above that no operation of the sensitive part of the soul can be performed without the body. In the souls of brute animals, however, there is no operation superior to those of the sensitive part, since they neither understand nor reason. This is evident from the fact that all animals of the same species operate in the same way, as though moved by nature and not as operating by art; every swallow builds its nest and every spider spins its web, in the same manner. The souls of brutes, then, are incapable of any operation that does not involve the body. Now, since every substance is possessed of some operation, the soul of a brute animal will be unable to exist apart from its body; so that it perishes along with the body.
Notes And this includes “talking” monkeys and “counting” horses, animals which excel at mimicry but who cannot apprehend universals.
3 Likewise, every form separate from matter is understood in act, for the agent intellect renders species intelligible in act by way of abstraction, as we see from what was said above. But if the soul of the brute animal continues to exist after its body has passed away, then that soul will be a form separate from matter, and therefore a form understood in act. And yet, as Aristotle says in De anima III , with things separate from matter, that which understands is identical with that which is understood. It follows that the soul of a brute animal, if it survives the body, will be intellectual; and this is impossible.
4 Then, too, in every thing capable of attaining a certain perfection, we find a natural desire for that perfection, since good is what all things desire, yet in such fashion that each thing desires the good proper to itself. In brutes, however, we find no desire for perpetual existence, but only a desire for the perpetuation of their several species, since we do observe in them the desire to reproduce and thereby perpetuate the species—a desire common also to plants and to inanimate things, though not as regards desire proper to an animal as such, because animal appetite is consequent upon apprehension. For, since the apprehending power of the sensitive soul is limited to the here and now, that soul cannot possibly be cognizant of perpetual existence. Nor, then, does it desire such existence with animal appetite. Therefore, the soul of a brute animal is incapable of perpetual existence…
Notes We skip some simple arguments to bring the best counterargument in the next three paragraphs, and its solution in the fourth.
9 Nevertheless, it would seem possible to show that the souls of such animals are immortal. For, if a thing possesses an operation through itself, distinctly its own, then it is subsisting through itself. But the sensitive soul in brutes enjoys an operation through itself, wherein the body has no part, namely, motion; for a mover is compounded of two parts, the one being mover and the other moved. Since the body is a thing moved, it remains that the soul is exclusively a mover, and, consequently, is subsisting through itself. Hence, the soul cannot be corrupted by accident, when the body is corrupted, for only those things are corrupted by accident which do not have being through themselves. Nor can the soul be corrupted through itself, since it neither has a contrary nor is composed of contraries. The result of the argument, therefore, is that the soul is altogether incorruptible.
10 And, seemingly, Plato’s argument that every soul is immortal comes to the same thing, namely, that the soul is a self-mover; and everything of this sort must be immortal. For the body dies only when its mover departs from it, and a thing cannot abandon itself. That is why Plato inferred that a thing which moves itself cannot die. And thus he came to the conclusion that every soul possessed of the power of motion, even that of brute animals, is immortal. Now, we have remarked that this argument is reductively the same as the preceding one, since, given Plato’s position that nothing moves without being moved, a thing that moves itself is a mover through itself and therefore has an operation through itself.
11 Now, Plato also maintained that the sensitive soul enjoys an operation of its own, not only in respect to movement, but also as regards sensation. For he said that sensation is a movement of the sensing soul itself, and that the soul, thus moved, moved the body to sensation; wherefore Plato said, in defining sense, that it is the motion of the soul through the body.
12 Now, these Platonic dicta are patently false. For the act of sensation is not an act of movement; rather, to sense is to be moved; since, through the sensible objects altering the condition of the senses in acting upon them, the animal is made actually sentient from being only potentially so. However, it cannot be maintained that the passivity of the sense in respect of the sensible is the same as that of the intellect in relation to the intelligible, so that sensation could then be an operation of the soul without a bodily instrument, just as understanding is. This is impossible, because the intellect grasps things in abstraction from matter and material conditions, which are individuating principles, whereas the sense does not, being manifestly limited to the perception of particulars, while the intellect attains to universals. Clearly, then, the senses are passive to things as existing in matter, but not the intellect, which is passive to things according as they are abstracted. Thus, in the intellect there is passivity in utter independence of corporeal matter, but not in the senses…
Notes Aha! Animals are sentient, our good saint says; the opposite thinking is a modern confusion. Senses are not intellection, a phrase so important you ought to repeat it to yourself.
14 There is also the fact that sense is overwhelmed by an exceedingly high degree of intensity on the part of its objects; but the intellect is not, because he who understands the higher intelligibles is more and not less able to understand other things. Hence, the state of passivity brought about in the sense by the sensible differs in kind from that which the intelligible causes in the intellect; the latter occurs without a bodily organ, the former with a bodily organ, the harmonious structure of whose parts is shattered by the pre-eminent power of some sensible objects…
Notes Students take note: more knowledge is better than less.
20 It is, then, clearly impossible for any operation of the brute animal’s soul to be independent of its body. And from this it can be inferred with necessity that the soul of the brute perishes with the body.
Notes So long, Spot.