Aristotle · a new plain-English translation from the original language
1| On the Soul, Book 1. Holding knowledge to be among the fine and honorable things, and one kind of knowledge more so than another, either in point of precision or in that it is knowledge of better and more admirable objects, on both these grounds we would reasonably place the inquiry into the soul among the first. Its knowledge also seems to contribute a great deal to truth as a whole, and above all to the study of nature; for the soul is, so to speak, a principle of living things. We seek to study and come to know its nature and its substance, and then whatever attributes belong to it — of which some seem to be affections proper to the soul itself, while others belong to living things as well, but on account of the soul. In every way it is among the most difficult things to arrive at any conviction about it. For since the inquiry is one shared with many other things — I mean the inquiry into substance and into what a thing is — it might perhaps seem to someone that there is a single method applicable to everything of which we wish to know the substance, just just as there is for the demonstration of the derivative properties that belong to things, so that this method would have to be sought out. But if there is no single method common to the question of what a thing is, the undertaking becomes still more difficult; for it will be necessary to grasp, in the case of each thing, what the approach is — and even once that is clear, whether it is some kind of demonstration, or division, or some other method.
2| Further, it involves many puzzles and false starts as to what one ought to start the inquiry from; for different things have different starting points, as with numbers and plane figures. Perhaps the first necessity is to determine under which of the genera the soul falls and what it is — I mean, whether it is a this-something and a substance, or a quality, or a quantity, or some other of the categories that have been distinguished — and further, whether it belongs among things that exist potentially, or is rather a kind of actuality; for this makes no small difference. One must also examine whether it is divisible or without parts, and whether every soul is of one form or not; and if it is not of one form, whether the various souls differ in species or in genus. As things stand, those who speak and inquire about the soul seem to examine only the human soul. One must take care not to overlook whether there is a single account of it, as there is of animal in general, or a different account for each kind, as of horse, dog, human being, god — the universal 'animal' being either nothing at all, or something posterior. Likewise for any other common term that might be predicated of it. Further, if there are not many souls but parts of a soul, one must ask whether it is the whole soul that ought to be investigated first, or its parts. It is difficult, too, to determine among these which are naturally distinct from one another, and whether one ought to investigate the parts first or their functions — for instance, thinking, or the intellect; perceiving, or the faculty of perception —
3| and likewise for the rest. And if the functions are to be investigated first, one might again raise the difficulty whether the objects correlative to them ought to be investigated before the functions themselves — for instance, the object of perception before the faculty of perception, and the object of thought before the faculty of thought. It appears that knowing what a thing is is useful not only for studying the causes of the attributes that belong to substances — as in mathematics, knowing what the straight and the curved are, or what a line and a plane are, is useful for seeing to how many right angles the angles of a triangle are equal — but also, conversely, the attributes contribute a great part toward knowing what the thing is; for when we are able to give an account, in line with how the thing appears to us, of its attributes, either all of them or most, then we shall also be in the best position to speak about its substance. For the starting point of every demonstration is what the thing is, so that in the case of as many definitions as fail to make the attributes known, and from which it is not even easy to conjecture about them, it is clear that all such definitions have been stated merely dialectically and emptily. There is a further difficulty about the affections of the soul: whether all of them are shared also by the body that has the soul, or whether there is something proper to the soul itself. This is a point that must be grasped, but it is not easy.
4| It appears that in most cases the soul undergoes and does nothing apart from the body — for instance, growing angry, being confident, desiring, and perceiving generally. Thinking seems most of all to be something proper to the soul alone; yet if this too is a kind of imagination, or does not occur without imagination, then not even this could exist apart from the body. So if there is some function or affection proper to the soul alone, it could exist separately; but if there is nothing proper to it, it could not be separable, but would be like the straight, which, as straight, has many things belonging to it — for instance, touching a bronze sphere at a point — yet the straight will not touch it if separated from body, since it is inseparable, if indeed it always exists together with some body. So too it seems that all the affections of the soul exist together with the body: anger, gentleness, fear, pity, confidence, and further joy, and loving and hating; for along with these the body undergoes something as well. This is shown by the fact that sometimes, even when strong and vivid affections occur, a person is not provoked to anger or fear, while at other times a person is moved by small and faint occasions, whenever the body is aroused and in the same state as when one is angry. And this is still more evident: people fall into the affections of one who is afraid when nothing fearful is happening at all.
5| If this is so, it is clear that the affections are accounts embodied in matter. So the definitions of them would be of this kind — for instance, that being angry is a certain motion of a body of such-and-such a kind, or of a part or capacity of it, produced by this for the sake of that. And for these reasons the study of the soul, either all of it or this kind of soul, already belongs to the student of nature. A student of nature and a dialectician would define each of these affections differently — for instance, what anger is: the dialectician will say it is a desire for retaliation, or something of that sort; the student of nature, a boiling of the blood and heat around the heart. Of these two, the latter gives the matter, the former the form and the account. For the account is the form of the thing, but it must exist in matter of a certain kind if it is to exist at all — just as the account of a house is of this sort, that it is a shelter preventing destruction by winds and rains and heat; but one person will state the matter — stones, bricks, timber — while another will state the form present in these, namely for the sake of these ends. Which of these, then, is the student of nature? Is it the one concerned with the matter, ignorant of the account, or the one concerned only with the account? Or rather the one who works from both together? Then what is each of the other two? Or is there no one who is concerned with the affections of matter that are not separable, nor even insofar as they are separable, but the student of nature is concerned with everything that is a function and affection of a body and matter of this or that kind —
6| while whatever is not of this kind belongs to someone else, and in some cases to a craftsman, if it should so happen, such as a builder or a doctor; and of things that are not separable, but insofar as they are not the affections of such-and-such a body, taken by abstraction, that belongs to the mathematician; while insofar as they are separated altogether, that belongs to the first philosopher. But we must return to the point from which the discussion began. We were saying that the affections of the soul are inseparable from the natural matter of living things insofar as they belong to them in this way — anger and fear — and not as line and plane are separable.
7| In examining the soul it is necessary, as we proceed, to raise together the difficulties one must resolve, and to bring in as well the opinions of our predecessors, of all who have declared anything about it, so that we may take up what has been well said, and be on guard against whatever has not been said well. The starting point of the inquiry is to set out what seems most of all to belong to it by nature. What is ensouled seems to differ from what is soulless most of all in two respects, motion and perception. And we have received from our predecessors roughly these same two points about the soul; for some say that what moves things is, above all and primarily, soul. Supposing that what is not itself moved cannot move something else, they took the soul to be one of the things that are moved. Hence Democritus says it is a kind of fire and something hot; for since shapes and atoms are unlimited, he says that the spherical ones are fire and soul, like the things called motes in the air, which appear in the sunbeams coming through windows, whose scattered mixture he calls the elements of the whole of nature. Leucippus says the same. Of these, the spherical ones are soul, because such shapes are especially able to penetrate everywhere and to move the rest while being themselves in motion, on the supposition that soul is what provides living things with motion.
8| This is also why breathing has been taken to be the boundary-mark of life: as what surrounds bodies compresses them, and squeezes out those shapes which give living things their motion — since these shapes themselves are never at rest — help comes from outside, from other such shapes entering in during breathing; for these prevent the shapes already present in living things from being expelled, by helping to hold back what compresses and congeals them, and an animal lives for just as long as it is able to do this. What is said by the Pythagoreans seems to carry the same thought: some of them said that soul is the specks of dust in the air, others that it is what moves these. The reason given for this view is that these specks are seen to be continuously in motion, even when there is a complete calm. Those who say that soul is what moves itself tend toward the same position; for all of these thinkers seem to have taken motion to be what is most proper to soul, and to hold that everything else is moved through the agency of soul, while soul is moved by itself, because they see nothing that moves something else without itself being in motion. In the same way Anaxagoras too says that soul is what moves things, as does anyone else who has said that intellect moved the whole — though not in quite the unqualified way that Democritus does.
9| For Democritus simply identifies soul and intellect; for he holds that what appears is true — which is why he approved of Homer's line that Hector 'lay with his wits astray.' He does not, then, treat intellect as some capacity concerned with truth, but says that soul and intellect are the same thing. Anaxagoras is less clear about the two: in many places he speaks of intellect as the cause of what is fine and right, but elsewhere he says this same thing is soul; for he says it is present in all animals, both great and small, both honored and less honored. But intellect in the sense of practical wisdom does not appear to be present alike in all animals, nor even in all human beings. So those who fixed their attention on the fact that ensouled things move took soul to be what is most capable of causing motion; those who fixed their attention on knowing and perceiving what is say that soul is the principles — some making these several, others making this one principle only, as Empedocles makes soul out of all the elements, while also holding that each of these elements is itself a soul, saying it this way: 'for by earth we see earth, by water water, by aether divine aether, but by fire consuming fire, by love love, and strife by baneful strife.'
10| In the same way Plato too, in the Timaeus, constructs soul out of the elements; for like is known by like, he holds, and things are made out of the principles. The same point was made in the discussions on philosophy: the living thing itself is made out of the idea of the one itself together with the primary length, breadth, and depth, and the rest similarly. And there is yet another way of putting it: intellect is the one, knowledge is the two — for it proceeds singly toward one thing — the number of the plane is opinion, and the number of the solid is perception; for the numbers were said to be the forms themselves and the principles, and they are made out of the elements. Things are judged, some by intellect, some by knowledge, some by opinion, some by perception, and these numbers are the forms of the things judged. And since soul was thought to be both capable of causing motion and capable of knowing, some thinkers wove the two together, declaring soul to be a number that moves itself. Thinkers differ over the principles — what they are and how many — and differing from both of these, those who mix the two together and declare the principles to be drawn from both and declare the principles to be drawn from both.
11| They differ also over the number of the principles: some say there is one, others several. And they render their account of soul to match: for they have taken the nature of the primary things to be what is capable of causing motion, and not unreasonably. This is why some have thought soul to be fire; for fire is the finest-parted of the elements and most nearly incorporeal, and moreover it is itself in motion and is what first moves the other elements. Democritus has put the matter rather more elegantly, declaring the reason for each of these two claims: soul, he says, is the same thing as intellect, and this is one of the primary and indivisible bodies, and it is capable of causing motion because of the smallness of its parts and its shape; and of shapes he says the spherical is the most mobile, and such is the shape of both intellect and fire. Anaxagoras, as we said before too, seems to distinguish soul from intellect, but in practice treats the two as a single nature, except that he posits intellect above all else as a principle; at any rate he says that intellect alone, of all things that are, is simple, unmixed, and pure. He assigns both functions to this same principle, both knowing and causing motion, saying that intellect moved the whole. And Thales too, to judge from what is recorded of him, seems to have supposed soul to be something that causes motion, if indeed he said that the stone has a soul because it moves iron.
12| Diogenes, like certain others, thought air to be the finest-parted of all things and a principle, and held that soul knows and causes motion for this reason: that in being the first thing, and everything else coming from it, it knows; and in being the finest-parted, it is capable of causing motion. Heraclitus too says that the principle is soul, if indeed it is the exhalation out of which he composes everything else; and this is the most incorporeal thing and always flowing, and what is in motion is known by what is in motion. He, like most others, held that things that are, are in motion. Alcmaeon seems to have held a view about soul close to these: he says it is immortal because it resembles the immortal beings, and that this belongs to it as something always in motion; for all the divine things too, he says, are in continuous and unceasing motion — the moon, the sun, the stars, and the whole heaven. Among the cruder thinkers, some have declared soul to be water, as Hippo did. They seem to have been persuaded by the case of seed, on the grounds that the seed of all things is moist; and indeed he refutes those who say soul is blood, on the ground that seed is not blood, and that seed is the primary soul. Others say it is blood, as Critias does, taking perceiving to be most proper to soul, and holding that this belongs to soul because of the nature of blood.
13| For every one of the elements has found some champion, except earth; no one has declared for earth alone, except insofar as someone has said that soul is made of all the elements, or is all of them. All thinkers define soul, one might say, by three marks: motion, perception, and the incorporeal; and each of these is traced back to the principles. This is why those who define soul by knowing make it either an element or something made out of the elements, and they speak much alike, except in one point: they say that like is known by like; and since soul knows everything, they compose it out of all the principles. So those who speak of some single cause and a single element also posit soul as one thing, such as fire or air; while those who speak of several principles make soul several as well. Anaxagoras alone says that intellect is unaffected, and has nothing in common with anything else. But being of this kind, how it will know, and for what reason, he has not said, nor is this clear from what has been said. Those who introduce oppositions among the principles compose soul out of the opposites as well; while those who take one member of an opposition, such as hot or cold or some other such thing, likewise posit soul as one of these single things.
14| That is also why they follow the names they use: some say the soul is hot, because life is named after this; others say it is called soul because of breathing and the cooling that comes with it. These, then, are the traditional views about the soul, and the reasons they give for holding them. We must first examine the question of motion. For perhaps it is not only false that the substance of the soul is such as those say who call the soul that which moves itself, or that which is capable of moving; rather, it may be one of the impossible things for motion to belong to it at all. Now that what moves need not itself be moved has been said earlier. Since everything that is moved is moved in two ways (for it is moved either in virtue of something else or in its own right; and we call things moved in virtue of something else which are moved by being in something that is moved, as sailors are — for they are not moved in the same way as the ship: the ship is moved in its own right, while they are moved by being in something that is moved. This is clear in the case of the parts of the body: for walking is the motion proper to feet, and this belongs to human beings too, but it does not belong to sailors when they are being carried along) — since, then, being moved is spoken of in two ways, we are now inquiring about the soul, whether it is moved in its own right and shares in motion. Since there are four kinds of motion — locomotion, alteration, decay, and growth — the soul, if it is moved, would be moved by one of these, or by several, or by all of them. And if it is moved not accidentally, motion would belong to it by nature; and if this is so, place would belong to it too, for all the motions mentioned occur in place.
15| If the substance of the soul is to move itself, then being moved will not belong to it accidentally, as it does to the white or to the three-cubit thing — for these too are moved, but accidentally: for it is the body to which they belong that is moved. That is also why there is no place belonging to them; but there will be a place belonging to the soul, if indeed it shares in motion by nature. Further, if it is moved by nature, it could also be moved by force; and if by force, then also by nature. The same holds for rest as well: to whatever place a thing is moved by nature, in that place it also rests by nature; and likewise, to whatever place a thing is moved by force, in that place it also rests by force. But what forced motions and forced restings would belong to the soul is not easy to render even for those willing to invent them. Further, if it is to be moved upward, it will be fire, and if downward, earth; for these are the motions of these bodies. And the same account holds for the intermediate bodies as well. Further, since the soul evidently moves the body, it is reasonable that it moves the body with the very motions by which it itself is moved. And if this is so, it is also true to say, converting the statement, that whatever motion the body is moved with, the soul is moved with that same motion too. But the body is moved by locomotion;
16| so the soul too would change along with the body, either shifting as a whole or shifting part by part. And if this is possible, it would also be possible for it to go out and come back in again; and from this it would follow that dead animals could rise again. As for motion that is accidental, the soul could also be moved by something else, for an animal could be pushed by force. But a thing to which being moved by itself belongs in its substance ought not to be moved by another, except accidentally — just as what is good in its own right, or for its own sake, ought not to be for the sake of something else, the one being what it is on account of something else, the other for the sake of something else. And one would most plausibly say that the soul is moved by the objects of perception, if indeed it is moved at all. But then again, if it moves itself, it too would be moved, so that if every motion is a displacement of the thing moved in respect of which it is moved, the soul too would be displaced from its substance, unless it moves itself only accidentally. But rather, the motion belongs to its very substance, in its own right. Some also say that the soul moves the body in which it is by moving itself in the same way — Democritus, for instance, speaking much like Philippus the comic playwright. For he says that Daedalus made the wooden statue of Aphrodite move by pouring in molten silver.
17| And Democritus speaks in a similar way: for he says that the indivisible spheres are in motion, because it is their nature never to remain still, and that they drag along and move the whole body with them. But we shall ask whether these same spheres also produce rest. How they will produce it is hard, or even impossible, to say. And in general the soul does not appear to move the animal in this way, but rather through some choice and thinking. Timaeus too gives a similar physical account of how the soul moves the body: because it is itself moved, it also moves the body, on account of being interwoven with it. For having been composed out of the elements, and divided according to the harmonic numbers, so that it might have an innate perception of harmony and the whole might be carried in concordant motions, he bent the straight line round into a circle; and having divided the one circle into two circles joined together at two points, he divided one of these again into seven circles, on the view that the motions of the heavens are the motions of the soul. Now first of all it is not right to say that the soul is a magnitude; for it is clear he means the soul of the whole to be such as what is called intellect is — for surely it is not like the perceptive soul, nor like the appetitive soul;
18| for the motion of these is not circular motion. But intellect is one and continuous, as thinking is; and thinking is thoughts, and these are one by succession, as a number is, not as a magnitude is. That is why intellect too is not continuous in that way, but is either without parts or not continuous as a magnitude is. For how indeed will it think, if it is a magnitude, by means of any one of its own parts? — parts either in the sense of magnitude, or in the sense of a point, if a point too must be called a part. Now if the parts are points, and these are infinite, clearly it will never traverse them all; and if they are parts in the sense of magnitude, it will think the same thing many times, or infinitely many times. But it evidently is possible for it to think a thing even once. And if contact with any one of its parts is sufficient, why need it move in a circle, or indeed have magnitude at all? But if it is necessary for it to think by making contact with the whole circle, what is the contact made with the parts? Further, how will that which has parts think that which has none, and that which has none think that which has parts? It is necessary, on this view, that intellect be this circle: for the motion of intellect is thinking, and the motion of a circle is revolution. If, then, thinking is revolution, the circle whose revolution of this kind is thinking would itself be intellect.
19| But then it will always be thinking something; for it must, if indeed the revolution is eternal. Practical thoughts have limits (for they are all for the sake of something else), but theoretical thoughts are bounded in the same way as the accounts that express them. And every account is either a definition or a demonstration. Now demonstrations proceed from a starting point, and have, in a sense, an end in the syllogism or the conclusion; and even if they are not brought to completion, still they do not bend back again to the starting point, but by continually taking on a middle term and an extreme they proceed in a straight line — whereas revolution bends back again to its starting point. But definitions are all bounded. Further, if the same revolution occurs many times, it will be necessary to think the same thing many times. Further, thinking seems to resemble a kind of rest and a coming to a stand, rather than motion; and the same holds for the syllogism as well. But surely what is not easy but forced is not a state of blessedness either; and if its motion is not its substance, it would be moving contrary to its nature. And it is also burdensome for it to be mixed with the body and unable to be released from it, and moreover something to be fled from, if indeed it is better for intellect to be without the body, as is customarily said and as many agree. But the cause of the heaven's being carried round in a circle is also unclear.
20| For neither is the substance of the soul the cause of its being carried in a circle — rather it is moved in this way only accidentally — nor is the body the cause; rather the soul is the cause for the body. But nor is it said to be because this is better; and yet it ought to be for this reason that god makes the soul move in a circle, because moving is better for it than staying at rest, and moving in this way rather than another. But since an inquiry of this kind belongs more properly to other discussions, let us leave it aside for now. But this absurdity attaches both to this account and to most of the accounts given about the soul: they connect the soul and set it into a body without further determining for what cause and in what condition of the body this happens. And yet this would seem to be necessary; for it is on account of their community that the one acts and the other is acted on, and the one is moved and the other moves, and none of these relations holds between things taken at random. But these thinkers only attempt to say what sort of thing the soul is, and add no further determination about the body that is to receive it — as though it were possible, as in the Pythagorean myths, for any soul at random to put on any body at random; for it seems that each thing has its own proper form and shape.
21| What they say is much like saying that carpentry puts on flutes; for a craft must use its instruments, and the soul must use the body. There is also another opinion handed down about the soul, one that seems plausible to many people no less than any of those mentioned, and one that has, so to speak, given an account of itself even before the discussions carried on in public: they say the soul is a kind of harmony. For harmony, they say, is a blending and composition of opposites, and the body is composed of opposites. And yet harmony is a certain ratio of the things mixed, or a composition of them, while the soul cannot be either of these. Further, causing motion does not belong to harmony, while everyone, so to speak, attributes this above all to the soul. It fits better to speak of harmony in connection with health, and generally with the excellences of the body, than in connection with the soul. This is most evident if one tries to render the affections and functions of the soul in terms of some harmony; for it is difficult to fit them together. Further, if we should speak of harmony with an eye to two things, it applies most properly to magnitudes that have motion and position, to their composition, when they are so fitted together as to admit nothing akin into themselves, and from this usage it is extended to the ratio of things mixed. On neither account, then, is it reasonable; and the composition of the parts of the body is very easy to examine and refute — for the compositions of the parts are many and occur in many ways.
22| Of what, then, or how, should one suppose the intellect to be a composition — or the perceptive part, or the appetitive part? Likewise it is absurd to say that the soul is the ratio of the mixture; for the mixture of the elements does not have the same ratio by which flesh is formed as that by which bone is formed. It will follow, then, that there are many souls, and throughout the whole body, if indeed all parts are mixtures of the elements, and the ratio of the mixture is harmony and soul. One might demand this same account from Empedocles too; for he says that each thing is by a certain ratio. Is the ratio, then, the soul, or is the soul rather something else that comes to be present in the limbs? Further, is love the cause of any mixture at random, or of the mixture according to the ratio? And is this love itself the ratio, or something besides the ratio? These questions, then, involve such difficulties. But if the soul is something other than the mixture, why is it that it is destroyed at the same time as being flesh, and as being the other parts of the animal, is destroyed? Further, if it is not the case that each of the parts has soul — unless the soul is the ratio of the mixture — what is it that perishes when the soul departs?
23| That the soul, then, can be neither a harmony nor something carried around in a circle is clear from what has been said. But that it is moved accidentally, as we said, and can move itself — as, for instance, being moved in that in which it is, and this in turn being moved by the soul — this is possible; but it is not possible for it to be moved locally in any other way. But one might more reasonably raise a difficulty about it as being moved, looking to considerations of the following kind. For we say that the soul feels pain and joy, is confident and afraid, and further feels anger and perceives and thinks discursively; and all of these seem to be motions. Hence one might suppose that it is moved. But this is not necessary; for even granting to the fullest extent that feeling pain, or joy, or discursive thought, are motions, and that each of these is a being-moved, still the being-moved is due to the soul — as, for instance, being angry or afraid is the heart being moved in such-and-such a way, and thinking discursively is perhaps something of this kind, or something else. Of these, some occur by a local motion of certain things, others by alteration — what sort, and how, is another discussion. But to say that the soul is angry is like saying that the soul weaves or builds a house;
24| for it is perhaps better not to say that the soul pities, or learns, or thinks discursively, but that the man does these with his soul — not as though the motion were in the soul, but sometimes as extending up to the soul, sometimes as proceeding from it: for instance, perception proceeds from these particular things, while recollection proceeds from the soul toward the motions or restings that are in the sense organs. But the intellect seems to come to be present as being a certain substance, and not to be destroyed. For it would be destroyed above all by the dimming that comes with old age, but as it is, the same thing happens as happens with the sense organs: if an old man could get an eye of a certain kind, he would see just as a young man does. So old age is not a case of the soul having been affected in some way, but of that in which the soul is — as in cases of drunkenness and disease. And so both understanding and contemplation fade away because something else within is being destroyed, while the intellect itself is unaffected. But discursive thought, and loving or hating, are not affections of that, but of this particular thing that has it, insofar as it has it; and that is why, when this perishes, it neither remembers nor loves; for these did not belong to the intellect, but to the composite, which has perished — while the intellect is perhaps something more divine, and unaffected.
25| That the soul, then, cannot be moved is clear from these considerations; and if it is not moved at all, then plainly it is not moved by itself either. But by far the least reasonable of the views mentioned is the claim that the soul is a number that moves itself; for impossibilities attach to it, first those that follow from being moved at all, and separately those that follow from calling it a number. For how must one conceive of a unit being moved, and by what, and how, given that it is without parts and without differentiation? For if it is both capable of moving and capable of being moved, it must be differentiated. Further, since they say that a moved point makes a line, and a moved line a plane, the motions of the units too will be lines; for the point is a unit having position, and the number of the soul is already somewhere and has position. Further, if one takes away a number or a unit from a number, a different number is left; but plants, and many animals too, when divided, live on, and seem to have the same soul in species. It would seem to make no difference to speak of units or of small bodies; for if points arise from the little spheres of Democritus, and only the quantity remains, there will be within it something that moves and something that is moved, just as in a continuum;
26| For what has just been said does not follow because of a difference in largeness or smallness, but because it is a quantity. Hence there must necessarily be something that moves the units. And if in the animal it is the soul that is the mover, then this holds for the number too, so that the soul is not both mover and moved, but only mover. Now it is somehow possible for this to be a unit; for it must have some differentia relative to the others; but what difference could there be for a unit-point except position? If, then, the units in the body and the points are different from one another, the units will be in the same place; for each unit will occupy the place of a point. Yet what prevents there being an infinite number of them in the same place, if two can be there? For things whose place is indivisible are themselves indivisible too. And if the points in the body are the number that constitutes the soul, or if the number arising from the points in the body is the soul, why do not all bodies have soul? For points seem to be present in everything, and infinitely many of them. Further, how is it possible for souls to be separated and released from bodies, if lines are not divided into points?
27| As we said, it turns out that in one respect this view says the same as those who posit the soul as a body made of fine parts, but in another respect, since it says, as Democritus does, that the body is moved by the soul, it has a peculiarity of its own that is absurd. For if the soul is present throughout the whole perceiving body, then, if the soul is some kind of body, there must be two bodies in the same place; and for those who call the soul a number, it follows that there are many points in a single point, or that every body has soul, unless some distinct number arises that is other than the points already present in the body. It also follows that the animal is moved by the number, in just the way we said Democritus too makes it move; for what difference does it make whether one speaks of small spheres or large units, or simply of units in motion? In either case it is necessary that the animal be moved by the motion of these things. For those, then, who have woven motion and number together into one, these consequences follow, and many others of the same kind. For it is impossible that such a thing be not only a definition of soul, but even an accidental attribute of it. This is clear if one tries to render the affections and functions of the soul from this account — reasonings, perceptions, pleasures, pains, and all the rest of that kind; for, as we said before, it is not even easy to divine these from such principles.
28| Three ways have been handed down by which people define the soul: some have declared it to be the thing most capable of motion, because it moves itself; others have declared it to be the body most fine-parted, or the least corporeal of all bodies. We have gone through fairly fully what difficulties and contradictions these views involve. It remains to examine in what sense the soul is said to be composed of the elements. People say this so that the soul may perceive the things that exist and know each of them; but many impossible consequences necessarily follow for the theory. They posit that like is known by like, as if positing that the soul is the very things it knows. But these elements are not the only things there are — there are also many other things, indeed perhaps infinite in number, namely the things composed out of them. Grant, then, that the soul knows and perceives the elements out of which each of these things is composed; but by what will it know or perceive the composite whole — for instance, what god is, or man, or flesh, or bone? And likewise for any other of the composite things; for none of these consists of the elements taken in just any condition, but in a certain ratio and combination, as Empedocles too says of bone: The gracious earth in its broad-breasted crucibles received two of the eight parts of gleaming Nestis, and four of Hephaestus; and the bones became white.
29| There is, then, no benefit in the elements being present in the soul, unless the ratios and the combination are present in it as well; for like will know each like thing, but it will know neither bone nor man at all, unless these too are present in it. That this is impossible needs no argument; for who would even raise the question whether a stone or a man is present in the soul? And likewise the good, or the not-good. And the same holds concerning everything else as well. Further, since being is spoken of in many ways (for it signifies now a this-something, now a quantity or a quality, or some other of the categories that have been distinguished), will the soul be composed out of all of them, or not? But there do not seem to be elements common to all of them. Is it, then, composed only of the elements of substances? How, then, does it come to know each of the other categories as well? Or will they say that each genus has its own elements and principles, out of which the soul is composed? Then it will be a quantity, a quality, and a substance all at once. But it is impossible for something composed out of the elements of quantity to be a substance and not a quantity. These consequences, then, and others like them, follow for those who say the soul is composed out of all the categories. It is also absurd to say, on the one hand, that like is unaffected by like, and yet, on the other, that like perceives like and knows like by like.
30| But they posit that perceiving is a kind of being affected and being moved; and likewise thinking and knowing. That the claim — made by Empedocles — that each thing is known by the bodily elements and by reference to what is like it involves many difficulties and awkward consequences is confirmed by what has just been said. For whatever is present in the bodies of animals as simply earth — bones, sinews, hairs — seems to perceive nothing, and so not even the things like it, and yet it ought to. Further, each of the principles will have more ignorance in it than understanding; for each will know one thing, but will be ignorant of many things, namely all the rest. It even follows for Empedocles that god is the least intelligent of all beings; for he alone will fail to know one of the elements, strife, whereas mortal things will know all of them, since each of them is composed out of all the elements. And in general, for what reason do not all existing things have soul, since everything is either an element or is composed out of one element, or several, or all of them? For it is necessary that it know one thing, or some things, or all things. One might also raise the question what it is that unifies the elements; for the elements at least resemble matter, and that which holds them together, whatever it is, is the most authoritative factor of all; but it is impossible for there to be anything superior to and ruling over the soul —
31| and still more impossible for there to be anything ruling over the intellect; for it is reasonable that intellect should be the most primary thing and, by nature, in authority, whereas they say the elements are the first of existing things. Both all those who, because the soul knows and perceives the things that exist, say it is composed out of the elements, and those who say it is the thing most capable of motion, are not speaking about soul in general. For not all things that perceive are capable of motion; for some animals evidently remain stationary in place. And yet it is this motion alone — motion in place — that the soul is thought to produce in the animal. And likewise for all those who make intellect and the perceptive faculty out of the elements; for plants evidently live without sharing in locomotion or in perception, and many animals do not have thought. But even if one were to concede these points, and posit that intellect is some part of the soul, and likewise the perceptive faculty, they still would not, on this view, be speaking universally about soul as such, nor about any soul as a whole, nor about any single soul. This same difficulty besets also the account given in the so-called Orphic verses; for it says that the soul enters in from the whole universe as animals breathe, being carried by the winds. But this cannot happen to plants, nor to some animals, since not all of them breathe.
32| This has escaped the notice of those who hold this view. If the soul must be made out of the elements, there is no need for it to be made out of all of them; one member of each pair of contraries is enough, since it can discriminate both itself and its opposite. For it is by the straight that we know both the straight itself and the curved (the ruler is the judge of both), whereas the curved is a judge neither of itself nor of the straight. And some say that soul is mixed in the whole universe, which is perhaps why Thales thought that all things are full of gods. But this has certain difficulties. For what reason does soul, when it is in air or in fire, not make an animal, while in mixed bodies it does, and this even though it is thought to be better in the former? One might also ask for what reason the soul in air is better and more immortal than the soul in animals. Either way the result is absurd and unreasonable: to call fire or air an animal is among the more unreasonable things to say, and yet to refuse to call them animals when soul is present in them is also absurd. They seem to have supposed that soul is present in these because the whole is uniform in kind with its parts. So they are forced to say that the soul too is uniform in kind with its parts, if it is by the cutting-off of some portion of the surrounding medium that the animals in living things become ensouled.
33| But if air when split apart is uniform in kind, while soul is non-uniform in its parts, then clearly some part of it will be present and some part will not. It is necessary, then, that soul either be uniform in its parts or else not be present in just any part whatever of the universe. It is plain, then, from what has been said, that knowing does not belong to soul because it is made of the elements, and that it is neither well said nor truly said that soul moves itself. But since knowing belongs to soul, and so do perceiving and forming opinion, and further desiring and wishing and the appetitions generally, and since motion from place to place also comes to belong to animals through soul, and further growth and prime and decay, the question is whether each of these belongs to the whole soul, and whether it is with the whole of it that we think and perceive and do and undergo each of the other things, or whether different things belong to different parts. And is living, then, situated in some one of these, or in several, or in all, or does it have some other cause? Now some say that soul is divisible, and that with one part it thinks and with another it desires. What then, if it is by nature divisible, holds the soul together?
34| For it is certainly not the body; on the contrary, it seems rather that the soul holds the body together, since at any rate when the soul departs the body breathes out and decays. If, then, something else makes the soul one, that above all would be soul. But then again one will have to ask about that thing too, whether it is one or has many parts. For if it is one, why should not soul immediately also be one? But if it is divisible, the argument will again ask what it is that holds that together, and so the process will go on to infinity. One might also raise a difficulty about the parts of the soul, as to what power each has in the body. For if the whole soul holds the whole body together, it would be fitting that each of the parts too should hold together some part of the body. But this seems impossible; it is hard even to imagine what part, or how, intellect could hold together. Plants too, and certain of the insects among animals, are observed to live when divided, as though each of the divided parts had the same soul in species, if not in number; at any rate each of the parts has perception and moves from place to place for some time. And if they do not continue to do so, there is nothing strange in that, since they do not have organs to preserve their nature.