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 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 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 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 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 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 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 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 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 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): —
Ὁς γαρ ἑκαστος εχει κρασιν μελεων πολυκαμπτων
Τως νοος ανθρωποισι παρεστηκεν; το γαρ αυτο
Εστιν, ὁπερ φρονεει, μελεων φυσις ανθρωποισι
Και πασιν και παντι; το γαρ πλεον εστι νοημα.
(Ut enim cuique complexio membrorum flexibilium se habet, ita mens hominibus adest: idem namque est, quod sapit, membrorum natura hominibus, et omnibus et omni: quod enim plus est, intelligentia est.)30
§ 21. Whoever has now gained from all these expositions a knowledge in abstracto, and therefore clear and certain, of what every one knows directly in concreto, i. e., as feeling, a knowledge that his will is the real inner nature of his phenomenal being, which manifests itself to him as idea, both in his actions and in their permanent substratum, his body, and that his will is that which is most immediate in his consciousness, though it has not as such completely passed into the form of idea in which object and subject stand over against each other, but makes itself known to him in a direct manner, in which he does not quite clearly distinguish subject and object, yet is not known as a whole to the individual himself, but only in its particular acts, – whoever, I say, has with me gained this conviction will find that of itself it affords him the key to the knowledge of the inmost being of the whole of nature; for he now transfers it to all those phenomena which are not given to him, like his own phenomenal existence, both in direct and indirect knowledge, but only in the latter, thus merely one-sidedly as idea alone. He will recognise this will of which we are speaking not only in those phenomenal existences which exactly resemble his own, in men and animals as their inmost nature, but the course of reflection will lead him to recognise the force which germinates and vegetates in the plant, and indeed the force through which the crystal is formed, that by which the magnet turns to the north pole, the force whose shock he experiences from the contact of two different kinds of metals, the force which appears in the elective affinities of matter as repulsion and attraction, decomposition and combination, and, lastly, even gravitation, which acts so powerfully throughout matter, draws the stone to the earth and the earth to the sun, – all these, I say, he will recognise as different only in their phenomenal existence, but in their inner nature as identical, as that which is directly known to him so intimately and so much better than anything else, and which in its most distinct manifestation is called will. It is this application of reflection alone that prevents us from remaining any longer at the phenomenon, and leads us to the thing in itself. Phenomenal existence is idea and nothing more. All idea, of whatever kind it may be, all object, is phenomenal existence, but the will alone is a thing in itself. As such, it is throughout not idea, but toto genere different from it; it is that of which all idea, all object, is the phenomenal appearance, the visibility, the objectification. It is the inmost nature, the kernel, of every particular thing, and also of the whole. It appears in every blind force of nature and also in the preconsidered action of man; and the great difference between these two is merely in the degree of the manifestation, not in the nature of what manifests itself.
§ 22. Now, if we are to think as an object this thing-in-itself (we wish to retain the Kantian expression as a standing formula), which, as such, is never object, because all object is its mere manifestation, and therefore cannot be it itself, we must borrow for it the name and concept of an object, of something in some way objectively given, consequently of one of its own manifestations. But in order to serve as a clue for the understanding, this can be no other than the most complete of all its manifestations, i. e., the most distinct, the most developed, and directly enlightened by knowledge. Now this is the human will. It is, however, well to observe that here, at any rate, we only make use of a denominatio a potiori, through which, therefore, the concept of will receives a greater extension than it has hitherto had. Knowledge of the identical in different phenomena, and of difference in similar phenomena, is, as Plato so often remarks, a sine qua non of philosophy. But hitherto it was not recognised that every kind of active and operating force in nature is essentially identical with will, and therefore the multifarious kinds of phenomena were not seen to be merely different species of the same genus, but were treated as heterogeneous. Consequently there could be no word to denote the concept of this genus. I therefore name the genus after its most important species, the direct knowledge of which lies nearer to us and guides us to the indirect knowledge of all other species. But whoever is incapable of carrying out the required extension of the concept will remain involved in a permanent misunderstanding. For by the word will he understands only that species of it which has hitherto been exclusively denoted by it, the will which is guided by knowledge, and whose manifestation follows only upon motives, and indeed merely abstract motives, and thus takes place under the guidance of the reason. This, we have said, is only the most prominent example of the manifestation of will. We must now distinctly separate in thought the inmost essence of this manifestation which is known to us directly, and then transfer it to all the weaker, less distinct manifestations of the same nature, and thus we shall accomplish the desired extension of the concept of will. From another point of view I should be equally misunderstood by any one who should think that it is all the same in the end whether we denote this inner nature of all phenomena by the word will or by any other. This would be the case if the thing-in-itself were something whose existence we merely inferred, and thus knew indirectly and only in the abstract. Then, indeed, we might call it what we pleased; the name would stand merely as the symbol of an unknown quantity. But the word will, which, like a magic spell, discloses to us the inmost being of everything in nature, is by no means an unknown quantity, something arrived at only by inference, but is fully and immediately comprehended, and is so familiar to us that we know and understand what will is far better than anything else whatever. The concept of will has hitherto commonly been subordinated to that of force, but I reverse the matter entirely, and desire that every force in nature should be thought as will. It must not be supposed that this is mere verbal quibbling or of no consequence; rather, it is of the greatest significance and importance. For at the foundation of the concept of force, as of all other concepts, there ultimately lies the knowledge in sense-perception of the objective world, that is to say, the phenomenon, the idea; and the concept is constructed out of this. It is an abstraction from the province in which cause and effect reign, i. e., from ideas of perception, and means just the causal nature of causes at the point at which this causal nature is no further etiologically explicable, but is the necessary presupposition of all etiological explanation. The concept will, on the other hand, is of all possible concepts the only one which has its source not in the phenomenal, not in the mere idea of perception, but comes from within, and proceeds from the most immediate consciousness of each of us, in which each of us knows his own individuality, according to its nature, immediately, apart from all form, even that of subject and object, and which at the same time is this individuality, for here the subject and the object of knowledge are one. If, therefore, we refer the concept of force to that of will, we have in fact referred the less known to what is infinitely better known; indeed, to the one thing that is really immediately and fully known to us, and have very greatly extended our knowledge. If, on the contrary, we subsume the concept of will under that of force, as has hitherto always been done, we renounce the only immediate knowledge which we have of the inner nature of the world, for we allow it to disappear in a concept which is abstracted from the phenomenal, and with which we can therefore never go beyond the phenomenal.
§ 23. The will as a thing in itself is quite different from its phenomenal appearance, and entirely free from all the forms of the phenomenal, into which it first passes when it manifests itself, and which therefore only concern its objectivity, and are foreign to the will itself. Even the most universal form of all idea, that of being object for a subject, does not concern it; still less the forms which are subordinate to this and which collectively have their common expression in the principle of sufficient reason, to which we know that time and space belong, and consequently multiplicity also, which exists and is possible only through these. In this last regard I shall call time and space the principium individuationis, borrowing an expression from the old schoolmen, and I beg to draw attention to this, once for all. For it is only through the medium of time and space that what is one and the same, both according to its nature and to its concept, yet appears as different, as a multiplicity of co-existent and successive phenomena. Thus time and space are the principium individuationis, the subject of so many subtleties and disputes among the schoolmen, which may be found collected in Suarez (Disp. 5, Sect. 3). According to what has been said, the will as a thing-in-itself lies outside the province of the principle of sufficient reason in all its forms, and is consequently completely groundless, although all its manifestations are entirely subordinated to the principle of sufficient reason. Further, it is free from all multiplicity, although its manifestations in time and space are innumerable. It is itself one, though not in the sense in which an object is one, for the unity of an object can only be known in opposition to a possible multiplicity; nor yet in the sense in which a concept is one, for the unity of a concept originates only in abstraction from a multiplicity; but it is one as that which lies outside time and space, the principium individuationis, i. e., the possibility of multiplicity. Only when all this has become quite clear to us through the subsequent examination of the phenomena and different manifestations of the will, shall we fully understand the meaning of the Kantian doctrine that time, space and causality do not belong to the thing-in-itself, but are only forms of knowing.
The uncaused nature of will has been actually recognised, where it manifests itself most distinctly, as the will of man, and this has been called free, independent. But on account of the uncaused nature of the will itself, the necessity to which its manifestation is everywhere subjected has been overlooked, and actions are treated as free, which they are not. For every individual action follows with strict necessity from the effect of the motive upon the character. All necessity is, as we have already said, the relation of the consequent to the reason, and nothing more. The principle of sufficient reason is the universal form of all phenomena, and man in his action must be subordinated to it like every other phenomenon. But because in self-consciousness the will is known directly and in itself, in this consciousness lies also the consciousness of freedom. The fact is, however, overlooked that the individual, the person, is not will as a thing-in-itself, but is a phenomenon of will, is already determined as such, and has come under the form of the phenomenal, the principle of sufficient reason. Hence arises the strange fact that every one believes himself a priori to be perfectly free, even in his individual actions, and thinks that at every moment he can commence another manner of life, which just means that he can become another person. But a posteriori, through experience, he finds to his astonishment that he is not free, but subjected to necessity; that in spite of all his resolutions and reflections he does not change his conduct, and that from the beginning of his life to the end of it, he must carry out the very character which he himself condemns, and as it were play the part he has undertaken to the end. I cannot pursue this subject further at present, for it belongs, as ethical, to another part of this work. In the meantime, I only wish to point out here that the phenomenon of the will which in itself is uncaused, is yet as such subordinated to the law of necessity, that is, the principle of sufficient reason, so that in the necessity with which the phenomena of nature follow each other, we may find nothing to hinder us from recognising in them the manifestations of will.