§ 17. In the first book we considered the idea merely as such, that is, only according to its general form. It is true that as far as the abstract idea, the concept, is concerned, we obtained a knowledge of it in respect of its content also, because it has content and meaning only in relation to the idea of perception, without which it would be worthless and empty. Accordingly, directing our attention exclusively to the idea of perception, we shall now endeavour to arrive at a knowledge of its content, its more exact definition, and the forms which it presents to us. And it will specially interest us to find an explanation of its peculiar significance, that significance which is otherwise merely felt, but on account of which it is that these pictures do not pass by us entirely strange and meaningless, as they must otherwise do, but speak to us directly, are understood, and obtain an interest which concerns our whole nature.
We direct our attention to mathematics, natural science, and philosophy, for each of these holds out the hope that it will afford us a part of the explanation we desire. Now, taking philosophy first, we find that it is like a monster with many heads, each of which speaks a different language. They are not, indeed, all at variance on the point we are here considering, the significance of the idea of perception. For, with the exception of the Sceptics and the Idealists, the others, for the most part, speak very much in the same way of an object which constitutes the basis of the idea, and which is indeed different in its whole being and nature from the idea, but yet is in all [pg 124] points as like it as one egg is to another. But this does not help us, for we are quite unable to distinguish such an object from the idea; we find that they are one and the same; for every object always and for ever presupposes a subject, and therefore remains idea, so that we recognised objectivity as belonging to the most universal form of the idea, which is the division into subject and object. Further, the principle of sufficient reason, which is referred to in support of this doctrine, is for us merely the form of the idea, the orderly combination of one idea with another, but not the combination of the whole finite or infinite series of ideas with something which is not idea at all, and which cannot therefore be presented in perception. Of the Sceptics and Idealists we spoke above, in examining the controversy about the reality of the outer world.
If we turn to mathematics to look for the fuller knowledge we desire of the idea of perception, which we have, as yet, only understood generally, merely in its form, we find that mathematics only treats of these ideas so far as they fill time and space, that is, so far as they are quantities. It will tell us with the greatest accuracy the how-many and the how-much; but as this is always merely relative, that is to say, merely a comparison of one idea with others, and a comparison only in the one respect of quantity, this also is not the information we are principally in search of.
Lastly, if we turn to the wide province of natural science, which is divided into many fields, we may, in the first place, make a general division of it into two parts. It is either the description of forms, which I call Morphology, or the explanation of changes, which I call Etiology. The first treats of the permanent forms, the second of the changing matter, according to the laws of its transition from one form to another. The first is the whole extent of what is generally called natural history. It teaches us, especially in the sciences of [pg 125] botany and zoology, the various permanent, organised, and therefore definitely determined forms in the constant change of individuals; and these forms constitute a great part of the content of the idea of perception. In natural history they are classified, separated, united, arranged according to natural and artificial systems, and brought under concepts which make a general view and knowledge of the whole of them possible. Further, an infinitely fine analogy both in the whole and in the parts of these forms, and running through them all (unité de plan), is established, and thus they may be compared to innumerable variations on a theme which is not given. The passage of matter into these forms, that is to say, the origin of individuals, is not a special part of natural science, for every individual springs from its like by generation, which is everywhere equally mysterious, and has as yet evaded definite knowledge. The little that is known on the subject finds its place in physiology, which belongs to that part of natural science I have called etiology. Mineralogy also, especially where it becomes geology, inclines towards etiology, though it principally belongs to morphology. Etiology proper comprehends all those branches of natural science in which the chief concern is the knowledge of cause and effect. The sciences teach how, according to an invariable rule, one condition of matter is necessarily followed by a certain other condition; how one change necessarily conditions and brings about a certain other change; this sort of teaching is called explanation. The principal sciences in this department are mechanics, physics, chemistry, and physiology.
If, however, we surrender ourselves to its teaching, we soon become convinced that etiology cannot afford us the information we chiefly desire, any more than morphology. The latter presents to us innumerable and infinitely varied forms, which are yet related by an unmistakable family likeness. These are for us ideas, and when only treated in this way, they remain always strange to us, [pg 126] and stand before us like hieroglyphics which we do not understand. Etiology, on the other hand, teaches us that, according to the law of cause and effect, this particular condition of matter brings about that other particular condition, and thus it has explained it and performed its part. However, it really does nothing more than indicate the orderly arrangement according to which the states of matter appear in space and time, and teach in all cases what phenomenon must necessarily appear at a particular time in a particular place. It thus determines the position of phenomena in time and space, according to a law whose special content is derived from experience, but whose universal form and necessity is yet known to us independently of experience. But it affords us absolutely no information about the inner nature of any one of these phenomena: this is called a force of nature, and it lies outside the province of causal explanation, which calls the constant uniformity with which manifestations of such a force appear whenever their known conditions are present, a law of nature. But this law of nature, these conditions, and this appearance in a particular place at a particular time, are all that it knows or ever can know. The force itself which manifests itself, the inner nature of the phenomena which appear in accordance with these laws, remains always a secret to it, something entirely strange and unknown in the case of the simplest as well as of the most complex phenomena. For although as yet etiology has most completely achieved its aim in mechanics, and least completely in physiology, still the force on account of which a stone falls to the ground or one body repels another is, in its inner nature, not less strange and mysterious than that which produces the movements and the growth of an animal. The science of mechanics presupposes matter, weight, impenetrability, the possibility of communicating motion by impact, inertia and so forth as ultimate facts, calls them forces of nature, and their necessary and [pg 127] orderly appearance under certain conditions a law of nature. Only after this does its explanation begin, and it consists in indicating truly and with mathematical exactness, how, where and when each force manifests itself, and in referring every phenomenon which presents itself to the operation of one of these forces. Physics, chemistry, and physiology proceed in the same way in their province, only they presuppose more and accomplish less. Consequently the most complete etiological explanation of the whole of nature can never be more than an enumeration of forces which cannot be explained, and a reliable statement of the rule according to which phenomena appear in time and space, succeed, and make way for each other. But the inner nature of the forces which thus appear remains unexplained by such an explanation, which must confine itself to phenomena and their arrangement, because the law which it follows does not extend further. In this respect it may be compared to a section of a piece of marble which shows many veins beside each other, but does not allow us to trace the course of the veins from the interior of the marble to its surface. Or, if I may use an absurd but more striking comparison, the philosophical investigator must always have the same feeling towards the complete etiology of the whole of nature, as a man who, without knowing how, has been brought into a company quite unknown to him, each member of which in turn presents another to him as his friend and cousin, and therefore as quite well known, and yet the man himself, while at each introduction he expresses himself gratified, has always the question on his lips: “But how the deuce do I stand to the whole company?”
Thus we see that, with regard to those phenomena which we know only as our ideas, etiology can never give us the desired information that shall carry us beyond this point. For, after all its explanations, they still remain quite strange to us, as mere ideas whose significance [pg 128] we do not understand. The causal connection merely gives us the rule and the relative order of their appearance in space and time, but affords us no further knowledge of that which so appears. Moreover, the law of causality itself has only validity for ideas, for objects of a definite class, and it has meaning only in so far as it presupposes them. Thus, like these objects themselves, it always exists only in relation to a subject, that is, conditionally; and so it is known just as well if we start from the subject, i.e., a priori, as if we start from the object, i.e., a posteriori. Kant indeed has taught us this.
But what now impels us to inquiry is just that we are not satisfied with knowing that we have ideas, that they are such and such, and that they are connected according to certain laws, the general expression of which is the principle of sufficient reason. We wish to know the significance of these ideas; we ask whether this world is merely idea; in which case it would pass by us like an empty dream or a baseless vision, not worth our notice; or whether it is also something else, something more than idea, and if so, what. Thus much is certain, that this something we seek for must be completely and in its whole nature different from the idea; that the forms and laws of the idea must therefore be completely foreign to it; further, that we cannot arrive at it from the idea under the guidance of the laws which merely combine objects, ideas, among themselves, and which are the forms of the principle of sufficient reason.
Thus we see already that we can never arrive at the real nature of things from without. However much we investigate, we can never reach anything but images and names. We are like a man who goes round a castle seeking in vain for an entrance, and sometimes sketching the façades. And yet this is the method that has been followed by all philosophers before me.
§ 18. In fact, the meaning for which we seek of that [pg 129] world which is present to us only as our idea, or the transition from the world as mere idea of the knowing subject to whatever it may be besides this, would never be found if the investigator himself were nothing more than the pure knowing subject (a winged cherub without a body). But he is himself rooted in that world; he finds himself in it as an individual, that is to say, his knowledge, which is the necessary supporter of the whole world as idea, is yet always given through the medium of a body, whose affections are, as we have shown, the starting-point for the understanding in the perception of that world. His body is, for the pure knowing subject, an idea like every other idea, an object among objects. Its movements and actions are so far known to him in precisely the same way as the changes of all other perceived objects, and would be just as strange and incomprehensible to him if their meaning were not explained for him in an entirely different way. Otherwise he would see his actions follow upon given motives with the constancy of a law of nature, just as the changes of other objects follow upon causes, stimuli, or motives. But he would not understand the influence of the motives any more than the connection between every other effect which he sees and its cause. He would then call the inner nature of these manifestations and actions of his body which he did not understand a force, a quality, or a character, as he pleased, but he would have no further insight into it. But all this is not the case; indeed the answer to the riddle is given to the subject of knowledge who appears as an individual, and the answer is will. This and this alone gives him the key to his own existence, reveals to him the significance, shows him the inner mechanism of his being, of his action, of his movements. The body is given in two entirely different ways to the subject of knowledge, who becomes an individual only through his identity with it. It is given as an idea in intelligent perception, as an object among objects and [pg 130] subject to the laws of objects. And it is also given in quite a different way as that which is immediately known to every one, and is signified by the word will. Every true act of his will is also at once and without exception a movement of his body. The act of will and the movement of the body are not two different things objectively known, which the bond of causality unites; they do not stand in the relation of cause and effect; they are one and the same, but they are given in entirely different ways,—immediately, and again in perception for the understanding. The action of the body is nothing but the act of the will objectified, i.e., passed into perception. It will appear later that this is true of every movement of the body, not merely those which follow upon motives, but also involuntary movements which follow upon mere stimuli, and, indeed, that the whole body is nothing but objectified will, i.e., will become idea. All this will be proved and made quite clear in the course of this work. In one respect, therefore, I shall call the body the objectivity of will; as in the previous book, and in the essay on the principle of sufficient reason, in accordance with the one-sided point of view intentionally adopted there (that of the idea), I called it the immediate object. Thus in a certain sense we may also say that will is the knowledge a priori of the body, and the body is the knowledge a posteriori of the will. Resolutions of the will which relate to the future are merely deliberations of the reason about what we shall will at a particular time, not real acts of will. Only the carrying out of the resolve stamps it as will, for till then it is never more than an intention that may be changed, and that exists only in the reason in abstracto. It is only in reflection that to will and to act are different; in reality they are one. Every true, genuine, immediate act of will is also, at once and immediately, a visible act of the body. And, corresponding to this, every impression upon the body is also, on the other hand, at once [pg 131] and immediately an impression upon the will. As such it is called pain when it is opposed to the will; gratification or pleasure when it is in accordance with it. The degrees of both are widely different. It is quite wrong, however, to call pain and pleasure ideas, for they are by no means ideas, but immediate affections of the will in its manifestation, the body; compulsory, instantaneous willing or not-willing of the impression which the body sustains. There are only a few impressions of the body which do not touch the will, and it is through these alone that the body is an immediate object of knowledge, for, as perceived by the understanding, it is already an indirect object like all others. These impressions are, therefore, to be treated directly as mere ideas, and excepted from what has been said. The impressions we refer to are the affections of the purely objective senses of sight, hearing, and touch, though only so far as these organs are affected in the way which is specially peculiar to their specific nature. This affection of them is so excessively weak an excitement of the heightened and specifically modified sensibility of these parts that it does not affect the will, but only furnishes the understanding with the data out of which the perception arises, undisturbed by any excitement of the will. But every stronger or different kind of affection of these organs of sense is painful, that is to say, against the will, and thus they also belong to its objectivity. Weakness of the nerves shows itself in this, that the impressions which have only such a degree of strength as would usually be sufficient to make them data for the understanding reach the higher degree at which they influence the will, that is to say, give pain or pleasure, though more often pain, which is, however, to some extent deadened and inarticulate, so that not only particular tones and strong light are painful to us, but there ensues a generally unhealthy and hypochondriacal disposition which is not distinctly understood. The identity of the body and the will shows itself further, [pg 132] among other ways, in the circumstance that every vehement and excessive movement of the will, i.e., every emotion, agitates the body and its inner constitution directly, and disturbs the course of its vital functions. This is shown in detail in “Will in Nature,” p. 27 of the second edition and p. 28 of the third.
Lastly, the knowledge which I have of my will, though it is immediate, cannot be separated from that which I have of my body. I know my will, not as a whole, not as a unity, not completely, according to its nature, but I know it only in its particular acts, and therefore in time, which is the form of the phenomenal aspect of my body, as of every object. Therefore the body is a condition of the knowledge of my will. Thus, I cannot really imagine this will apart from my body. In the essay on the principle of sufficient reason, the will, or rather the subject of willing, is treated as a special class of ideas or objects. But even there we saw this object become one with the subject; that is, we saw it cease to be an object. We there called this union the miracle κατ᾽ εξοχην, and the whole of the present work is to a certain extent an explanation of this. So far as I know my will specially as object, I know it as body. But then I am again at the first class of ideas laid down in that essay, i.e., real objects. As we proceed we shall see always more clearly that these ideas of the first class obtain their explanation and solution from those of the fourth class given in the essay, which could no longer be properly opposed to the subject as object, and that, therefore, we must learn to understand the inner nature of the law of causality which is valid in the first class, and of all that happens in accordance with it from the law of motivation which governs the fourth class.
The identity of the will and the body, of which we have now given a cursory explanation, can only be proved in the manner we have adopted here. We have proved this identity for the first time, and shall do so more and [pg 133] more fully in the course of this work. By “proved” we mean raised from the immediate consciousness, from knowledge in the concrete to abstract knowledge of the reason, or carried over into abstract knowledge. On the other hand, from its very nature it can never be demonstrated, that is, deduced as indirect knowledge from some other more direct knowledge, just because it is itself the most direct knowledge; and if we do not apprehend it and stick to it as such, we shall expect in vain to receive it again in some indirect way as derivative knowledge. It is knowledge of quite a special kind, whose truth cannot therefore properly be brought under any of the four rubrics under which I have classified all truth in the essay on the principle of sufficient reason, § 29, the logical, the empirical, the metaphysical, and the metalogical, for it is not, like all these, the relation of an abstract idea to another idea, or to the necessary form of perceptive or of abstract ideation, but it is the relation of a judgment to the connection which an idea of perception, the body, has to that which is not an idea at all, but something toto genere different, will. I should like therefore to distinguish this from all other truth, and call it κατ᾽ εξοχην philosophical truth. We can turn the expression of this truth in different ways and say: My body and my will are one;—or, What as an idea of perception I call my body, I call my will, so far as I am conscious of it in an entirely different way which cannot be compared to any other;—or, My body is the objectivity of my will;—or, My body considered apart from the fact that it is my idea is still my will, and so forth.27
§ 19. In the first book we were reluctantly driven to explain the human body as merely idea of the subject which knows it, like all the other objects of this world of perception. But it has now become clear that what enables us consciously to distinguish our own body from all other objects which in other respects are precisely the [pg 134] same, is that our body appears in consciousness in quite another way toto genere different from idea, and this we denote by the word will; and that it is just this double knowledge which we have of our own body that affords us information about it, about its action and movement following on motives, and also about what it experiences by means of external impressions; in a word, about what it is, not as idea, but as more than idea; that is to say, what it is in itself. None of this information have we got directly with regard to the nature, action, and experience of other real objects.
It is just because of this special relation to one body that the knowing subject is an individual. For regarded apart from this relation, his body is for him only an idea like all other ideas. But the relation through which the knowing subject is an individual, is just on that account a relation which subsists only between him and one particular idea of all those which he has. Therefore he is conscious of this one idea, not merely as an idea, but in quite a different way as a will. If, however, he abstracts from that special relation, from that twofold and completely heterogeneous knowledge of what is one and the same, then that one, the body, is an idea like all other ideas. Therefore, in order to understand the matter, the individual who knows must either assume that what distinguishes that one idea from others is merely the fact that his knowledge stands in this double relation to it alone; that insight in two ways at the same time is open to him only in the case of this one object of perception, and that this is to be explained not by the difference of this object from all others, but only by the difference between the relation of his knowledge to this one object, and its relation to all other objects. Or else he must assume that this object is essentially different from all others; that it alone of all objects is at once both will and idea, while the rest are only ideas, i.e., only phantoms. Thus he must assume that his body is the only real individual in [pg 135] the world, i.e., the only phenomenon of will and the only immediate object of the subject. That other objects, considered merely as ideas, are like his body, that is, like it, fill space (which itself can only be present as idea), and also, like it, are causally active in space, is indeed demonstrably certain from the law of causality which is a priori valid for ideas, and which admits of no effect without a cause; but apart from the fact that we can only reason from an effect to a cause generally, and not to a similar cause, we are still in the sphere of mere ideas, in which alone the law of causality is valid, and beyond which it can never take us. But whether the objects known to the individual only as ideas are yet, like his own body, manifestations of a will, is, as was said in the First Book, the proper meaning of the question as to the reality of the external world. To deny this is theoretical egoism, which on that account regards all phenomena that are outside its own will as phantoms, just as in a practical reference exactly the same thing is done by practical egoism. For in it a man regards and treats himself alone as a person, and all other persons as mere phantoms. Theoretical egoism can never be demonstrably refuted, yet in philosophy it has never been used otherwise than as a sceptical sophism, i.e., a pretence. As a serious conviction, on the other hand, it could only be found in a madhouse, and as such it stands in need of a cure rather than a refutation. We do not therefore combat it any further in this regard, but treat it as merely the last stronghold of scepticism, which is always polemical. Thus our knowledge, which is always bound to individuality and is limited by this circumstance, brings with it the necessity that each of us can only be one, while, on the other hand, each of us can know all; and it is this limitation that creates the need for philosophy. We therefore who, for this very reason, are striving to extend the limits of our knowledge through philosophy, will treat this sceptical argument of theoretical egoism [pg 136] which meets us, as an army would treat a small frontier fortress. The fortress cannot indeed be taken, but the garrison can never sally forth from it, and therefore we pass it by without danger, and are not afraid to have it in our rear.
The double knowledge which each of us has of the nature and activity of his own body, and which is given in two completely different ways, has now been clearly brought out. We shall accordingly make further use of it as a key to the nature of every phenomenon in nature, and shall judge of all objects which are not our own bodies, and are consequently not given to our consciousness in a double way but only as ideas, according to the analogy of our own bodies, and shall therefore assume that as in one aspect they are idea, just like our bodies, and in this respect are analogous to them, so in another aspect, what remains of objects when we set aside their existence as idea of the subject, must in its inner nature be the same as that in us which we call will. For what other kind of existence or reality should we attribute to the rest of the material world? Whence should we take the elements out of which we construct such a world? Besides will and idea nothing is known to us or thinkable. If we wish to attribute the greatest known reality to the material world which exists immediately only in our idea, we give it the reality which our own body has for each of us; for that is the most real thing for every one. But if we now analyse the reality of this body and its actions, beyond the fact that it is idea, we find nothing in it except the will; with this its reality is exhausted. Therefore we can nowhere find another kind of reality which we can attribute to the material world. Thus if we hold that the material world is something more than merely our idea, we must say that besides being idea, that is, in itself and according to its inmost nature, it is that which we find immediately in ourselves as will. I say according to its inmost nature; but we must first come [pg 137] to know more accurately this real nature of the will, in order that we may be able to distinguish from it what does not belong to itself, but to its manifestation, which has many grades. Such, for example, is the circumstance of its being accompanied by knowledge, and the determination by motives which is conditioned by this knowledge. As we shall see farther on, this does not belong to the real nature of will, but merely to its distinct manifestation as an animal or a human being. If, therefore, I say,—the force which attracts a stone to the earth is according to its nature, in itself, and apart from all idea, will, I shall not be supposed to express in this proposition the insane opinion that the stone moves itself in accordance with a known motive, merely because this is the way in which will appears in man.28 We shall now proceed more clearly and in detail to prove, establish, and develop to its full extent what as yet has only been provisionally and generally explained.29
§ 20. As we have said, the will proclaims itself primarily in the voluntary movements of our own body, as the inmost nature of this body, as that which it is besides being object of perception, idea. For these voluntary movements are nothing else than the visible aspect of the individual acts of will, with which they are directly coincident and identical, and only distinguished through the form of knowledge into which they have passed, and in which alone they can be known, the form of idea.
But these acts of will have always a ground or reason outside themselves in motives. Yet these motives never determine more than what I will at this time, in this [pg 138] place, and under these circumstances, not that I will in general, or what I will in general, that is, the maxims which characterise my volition generally. Therefore the inner nature of my volition cannot be explained from these motives; but they merely determine its manifestation at a given point of time: they are merely the occasion of my will showing itself; but the will itself lies outside the province of the law of motivation, which determines nothing but its appearance at each point of time. It is only under the presupposition of my empirical character that the motive is a sufficient ground of explanation of my action. But if I abstract from my character, and then ask, why, in general, I will this and not that, no answer is possible, because it is only the manifestation of the will that is subject to the principle of sufficient reason, and not the will itself, which in this respect is to be called groundless. At this point I presuppose Kant's doctrine of the empirical and intelligible character, and also my own treatment of the subject in “The Fundamental Problems of Ethics,” pp. 48, 58, and 178, et seq., of first edition (p. 174, et seq., of second edition). I shall also have to speak more fully on the question in the Fourth Book. For the present, I have only to draw attention to this, that the fact of one manifestation being established through another, as here the deed through the motive, does not at all conflict with the fact that its real nature is will, which itself has no ground; for as the principle of sufficient reason in all its aspects is only the form of knowledge, its validity extends only to the idea, to the phenomena, to the visibility of the will, but not to the will itself, which becomes visible.
If now every action of my body is the manifestation of an act of will in which my will itself in general, and as a whole, thus my character, expresses itself under given motives, manifestation of the will must be the inevitable condition and presupposition of every action. For the fact of its manifestation cannot depend upon something [pg 139] which does not exist directly and only through it, which consequently is for it merely accidental, and through which its manifestation itself would be merely accidental. Now that condition is just the whole body itself. Thus the body itself must be manifestation of the will, and it must be related to my will as a whole, that is, to my intelligible character, whose phenomenal appearance in time is my empirical character, as the particular action of the body is related to the particular act of the will. The whole body, then, must be simply my will become visible, must be my will itself, so far as this is object of perception, an idea of the first class. It has already been advanced in confirmation of this that every impression upon my body also affects my will at once and immediately, and in this respect is called pain or pleasure, or, in its lower degrees, agreeable or disagreeable sensation; and also, conversely, that every violent movement of the will, every emotion or passion, convulses the body and disturbs the course of its functions. Indeed we can also give an etiological account, though a very incomplete one, of the origin of my body, and a somewhat better account of its development and conservation, and this is the substance of physiology. But physiology merely explains its theme in precisely the same way as motives explain action. Thus the physiological explanation of the functions of the body detracts just as little from the philosophical truth that the whole existence of this body and the sum total of its functions are merely the objectification of that will which appears in its outward actions in accordance with a motive, as the establishment of the individual action through the motive and the necessary sequence of the action from the motive conflicts with the fact that action in general, and according to its nature, is only the manifestation of a will which itself has no ground. If, however, physiology tries to refer even these outward actions, the immediate voluntary movements, to causes in the organism,—for example, if it [pg 140] explains the movement of the muscles as resulting from the presence of fluids (“like the contraction of a cord when it is wet,” says Reil in his “Archiv für Physiologie,” vol. vi. p. 153), even supposing it really could give a thorough explanation of this kind, yet this would never invalidate the immediately certain truth that every voluntary motion (functiones animales) is the manifestation of an act of will. Now, just as little can the physiological explanation of vegetative life (functiones naturales vitales), however far it may advance, ever invalidate the truth that the whole animal life which thus develops itself is the manifestation of will. In general, then, as we have shown above, no etiological explanation can ever give us more than the necessarily determined position in time and space of a particular manifestation, its necessary appearance there, according to a fixed law; but the inner nature of everything that appears in this way remains wholly inexplicable, and is presupposed by every etiological explanation, and merely indicated by the names, force, or law of nature, or, if we are speaking of action, character or will. Thus, although every particular action, under the presupposition of the definite character, necessarily follows from the given motive, and although growth, the process of nourishment, and all the changes of the animal body take place according to necessarily acting causes (stimuli), yet the whole series of actions, and consequently every individual act, and also its condition, the whole body itself which accomplishes it, and therefore also the process through which and in which it exists, are nothing but the manifestation of the will, the becoming visible, the objectification of the will. Upon this rests the perfect suitableness of the human and animal body to the human and animal will in general, resembling, though far surpassing, the correspondence between an instrument made for a purpose and the will of the maker, and on this account appearing as design, i.e., the teleological explanation of [pg 141] the body. The parts of the body must, therefore, completely correspond to the principal desires through which the will manifests itself; they must be the visible expression of these desires. Teeth, throat, and bowels are objectified hunger; the organs of generation are objectified sexual desire; the grasping hand, the hurrying feet, correspond to the more indirect desires of the will which they express. As the human form generally corresponds to the human will generally, so the individual bodily structure corresponds to the individually modified will, the character of the individual, and therefore it is throughout and in all its parts characteristic and full of expression. It is very remarkable that Parmenides already gave expression to this in the following verses, quoted by Aristotle (Metaph. iii. 5):—