LECTIO SEVEN

             § 309. Having distinguished the capacities of 'soul' from one another, and explained how and in what order he means to discuss them, the Philosopher now treats of them in the order indicated. This he does in two stages. First, he examines one by one the divisions into which he has analysed soul, coming to certain conclusions about all of them. After that, in the penultimate chapter of this book, where he says, 'All living things have the vegetative soul', he explains the interrelation of these 'parts' of soul.

             The former section divides into four treatises:

 (1) On the vegetative principle.

 (2) Starting at 'These questions being settled', on the sensitive principle.

 (3) At 'As to the part of the soul by which it knows', on the intellect.

 (4) At 'We must now consider' on the principle of local movement.

             To the appetitive principle is assigned no special treatise, because it does not of itself constitute any special grade of animate being. It is treated, along with motion, in Book III.

             Treatise (1) divides into two parts: the first part contains certain preliminaries to the study of the vegetative principle; the second, beginning at 'Since the vegetative and generative', contains Aristotle's conclusions on this matter. The former section again divides into (a) a statement of his aim, and (b) at 'For the most natural,' an exposition of certain things which an understanding of the vegetative principle presupposes.

             § 310. (a) First of all, then, he remarks that if, as we saw in the last chapter, objects and acts have to be defined before potencies, and the fundamental potency before those which follow from it, we ought in consequence to begin by discussing nourishment, the object with which the vegetative principle deals, and generation, which is this principle's activity. Now this principle should be discussed first; because, whenever it coexists in one subject with the other parts of 'soul', it is as it were their foundation; for through its activities the physical reality, underlying both sensitivity and intelligence, is maintained. Besides, this part of 'soul' is common to all living things, and while it can exist apart from the others, they cannot exist without it; and it is always best to start with the more general datum. Its activities, then, being reproduction and taking nourishment, it is with these that we begin.

             § 311. (b) Next, when he says 'For the most natural' he settles a few preliminary questions; and this in two stages. First, he shows that to generate one's kind is an act of the vegetative principle. This he had not yet shown, having spoken so far only of growth and decay in this connection. Next, at 'The soul is cause', he proves that a soul is the principle of all vegetative activities (for indeed these activities might have seemed to come from mere nature, and not from a life-principle, since it is of their essence that they make use of the active and passive physical and corporeal qualities; and still more, because life in plants is hard to discern and latent).

             § 312. The first point is proved thus. All activities found to be natural to all living things spring, as we have seen, from the vegetative principle as the fundamental condition of there being any life at all; and reproduction being one such activity, it must spring from the vegetative principle. Indeed, he relates reproduction to this principle because it is, as he says, the activity most natural to all living things; and this because in a certain way the process of generation is common to all beings, even to inanimate things. Of course the latter are generated differently; still, they are generated. But with them the generating principle is something quite exterior to the thing that comes into being, whereas animate things proceed from an interior principle inasmuch as they spring from the seed with its potentiality for new life.

             § 313. There are, however, three exceptions to the general rule that living things reproduce their kind. First, the immature; for children do not beget. Secondly, those defective in some essential requirement, such as the impotent and eunuchs. Thirdly, the case of spontaneous generation from putrefying matter. In this last case the life resulting is of a type so inferior that the general environment suffices to cause it, i.e. the influence of the heavenly bodies and the right material conditions. But these causes alone are not sufficient to generate the higher animals: this requires also the activity of particular causes of the same species as the animals generated.

             § 314. Hence he says that any living thing can reproduce its kind provided that it is 'mature' (excluding children) and not 'defective' (excluding eunuchs and such like) and that the effect generated is not 'spontaneously generated' (excluding things produced by putrefaction, which are said to come to be 'spontaneously' because they spring up without seed, which is something like the way things are done, as we say, spontaneously, i.e. not under exterior compulsion). And what he means by living things producing their like is that animals produce animals and plants plants; and more precisely that each species produces its like, men producing men and olive-trees olive-trees. And the reason why living things produce their like is that they may continuously participate, so far as they can, in what is divine and immortal, i.e. that they may become as like to the divine as possible.

             § 315. For just as there are degrees of perfection in one and the same being, inasmuch as it develops from potentiality into act, so there are more and less perfect beings; and therefore the more perfect a given thing is in itself, the more does it resemble the more perfect beings. Hence just as, while a thing is moving from potency to actuality, and as long as it is still in potency, it has a natural relation and inclination towards actuality, and when it attains incomplete actuality it still desires a more complete actuality, so, in the same way, everything in a lower form of existence is inclined to the maximum possible assimilation to the higher form. Hence Aristotle adds that 'all things seek this', i.e. an assimilation to what is divine and imperishable, and this is that 'for the sake of which they do all that they do by nature'.

             § 316. Now 'that for the sake of which' something is done can mean two things: (a) the end aimed at directly by an activity, as health is the direct aim of doctoring; and (b) as the end aimed at indirectly; and this again may be taken in two ways. For we might take the 'end' to include also that subject in which the activity's direct aim is realised, and in this sense the end of doctoring would be not health merely, but a healthy body. Alternately, we could mean by 'end' not only what is principally intended, but also the means to be employed; we might say, e.g. that the end of doctoring was to keep the body warm, because warmth preserves that harmony of elements in the body which is health. So then, when it is said here that perpetuity of being is the reason for the activity in question, we are referring either to some imperishable nature which material things strive, by reproducing their kind, to resemble, or to the reproductive process itself, which is the means to this end.

             § 317. Because, then, the lower forms of life are unable to share in the perpetual, divine being by way of continuity of their individual identity--since it is absolutely and intrinsically necessary (not merely a necessity imposed from without) that all corruptible things should individually pass away since they are intrinsically material--it follows that they can only share in it so far as their nature allows; the more lasting natures more, the less lasting less; but all sharing in it continuously by way of reproduction; each remaining one and the same, not indeed literally, but 'as if the same', in the sense that one and the same species remains. Hence he adds that it does not remain one thing numerically, i.e. in the strict sense of the terms, but only specifically; and this because each individual reproduces its like according to species.

             § 318. Then, at 'The soul is the cause', he shows the connection between the activities attributed to the vegetative principle and the soul. And he does two things here: first, he establishes a truth; secondly, at 'Empedocles', he points out an error. The proof of the truth, again, has two stages. First, he states his aim, asserting that the soul is principle and cause of the living body; and since these terms are ambiguous, going on to distinguish three senses in which this proposition is to be taken. Soul, he says, is cause of the living body, (a) as the source of its movements, (b) as 'that for the sake of which', or end, and (c) as its 'essence' or form.

             § 319. In the second place, at 'That it is', he proves his proposition; and first with regard to soul being the cause of the living body as its form. Here he uses two arguments: first, the cause of anything as its 'essence', i.e. form, is the same as the cause of its being, for everything has actual existence through its form. Now it is the soul that gives being to living things; for their being is precisely their life, which they have from the soul. Hence the soul causes the body as its form.

             § 320. Then the second argument, at 'Further': the actuality of anything is the immanent idea and form of the thing as in potency. Now the soul, as we have seen, is the living body's actuality. Therefore it is the form and immanent idea of the living body.

             § 321. Next, at 'It is manifest', he shows that the soul is a final cause of living bodies. For Nature, like mind, acts for a purpose, as was shown in Book II of the Physics. But the mind, in its constructions, always orders and arranges materials in view of some form. So also, then, does Nature. If then the soul is the living body's form, it must also be its final cause.

             § 322. Moreover the soul is the end not only of living bodies, but also of all sublunary natural bodies. For it is evident that all such bodies are, as it were, instruments of 'soul'--not only of animals' souls but of the plant soul as well. Thus men turn to their own purposes both animals and inanimate things; animals make use of plants and inanimate things; and plants of the inanimate things which support and feed them. If then the action of things is an index to their nature it seems that all inanimate bodies are naturally instruments of animate things and exist for their sake. And, incidentally, the lower animate things exist for the higher. After this he distinguishes 'for the sake of' into the two aspects which have already been explained.

             § 323. Thirdly, at 'But also the soul', he shows that the soul is the source of movement in the body. The form of every natural body, he explains, is the principle of the characteristic movement of that particular kind of body--e.g. the form of fire is cause of fire's movement. Now certain movements are characteristic of living bodies; such, for instance, as that by which animals move themselves about from place to place, though this, to be sure, is not found in all living things. Similarly sensation involves a certain alteration of the body not found except in beings that have soul. So too with growth and decay; these movements imply the use of food and therefore also a soul. The soul, then, is the principle of all these movements.

415b 28-416a 18

THE VEGETATIVE PRINCIPLE CONTINUED

TWO ERRORS REFUTED

             EMPEDOCLES is mistaken here, adding that growth occurs in plants by their sending a root downwards, because earth is by nature below, and also upwards because of fire.§ 324

             Nor did he understand aright 'up' and 'down'; for these are not for all things the same as for the Universe; but roots of plants correspond to the head in animals, if it is permissible to identify organs by their functions. For we reckon those organs to be the same which perform the same operations.§§ 325-7

             Besides, what holds fire and earth together if they tend in contrary directions? They must come apart if there is nothing to prevent this. But if there is such a thing, it must be the soul; and be also the cause of growth and nourishment.§ 328

             Now it seems to some that the nature of fire is the sole cause of growth and nutrition; for it certainly seems to be the only one of the bodies and elements that is self-nourishing and self-increasing. Whence the notion that it is this that is operative in plants and animals.§§ 329-30

             It is indeed a concomitant cause, but the cause absolutely is not fire, but rather the soul. For the increase of fire is infinite so long as there is anything combustible. But there are limitations to all things that subsist naturally, and some definite principle governs their dimensions and growth. And this belongs to the soul, not to fire, and to a specific principle rather than to matter.§§ 331-2