P 327 THE TRANSCENDENTAL DIALECTIC BOOK II THE DIALECTICAL INFERENCES OF PURE REASON ALTHOUGH a purely transcendental idea is, in accordance with the original laws of reason, a quite necessary product of reason, its object, it may yet be said, is something of which we have no concept. For in respect of an object which is adequate to the demands of reason, it is not, in fact, possible that we should ever be able to form a concept of the understanding, that is, a concept that allows of being exhibited and intuited in a possible experience. But we should be better advised and less likely to be misunderstood if we said that although we cannot have any knowledge of the object which corresponds to an idea, we yet have a problematic concept of it. The transcendental (subjective) reality of the pure concepts of reason depends on our having been led to such ideas by a necessary syllogism. There will therefore be syllogisms which contain no empirical premisses, and by means of which we conclude from something which we know to something else of which we have no concept, and to which, owing to an inevitable illusion, we yet ascribe objective reality. These conclusions are, then, rather to be called pseudo-rational than rational, although in view of their origin they may well lay claim to the latter title, since they are not fictitious and have not arisen fortuitously, but have sprung from the very nature of reason. They are sophistications not of men but of pure reason itself. Even the wisest of men cannot free himself from them. After long effort he perhaps succeeds in guarding himself against P 328 actual error; but he will never be able to free himself from the illusion, which unceasingly mocks and torments him. There are, then, only three kinds of dialectical syllogisms -- just so many as there are ideas in which their conclusions result. In the first kind of syllogism I conclude from the transcendental concept of the subject, which contains nothing manifold, the absolute unity of this subject itself, of which, however, even in so doing, I possess no concept whatsoever. This dialectical inference I shall entitle the transcendental paralogism. The second kind of pseudo-rational inference is directed to the transcendental concept of the absolute totality of the series of conditions for any given appearance. From the fact that my concept of the unconditioned synthetic unity of the series, as thought in a certain way, is always self-contradictory, I conclude that there is really a unity of the opposite kind, although of it also I have no concept. The position of reason in these dialectical inferences I shall entitle the antinomy of pure reason. Finally, in the third kind of pseudo-rational inference, from the totality of the conditions under which objects in general, in so far as they can be given me, have to be thought, I conclude to the absolute synthetic unity of all conditions of the possibility of things in general, i.e. from things which I do not know through the merely transcendental concept of them I infer an ens entium, which I know even less through any transcendental concept, and of the unconditioned necessity of which I can form no concept whatsoever. This dialectical syllogism I shall entitle the ideal of pure reason. SECOND BOOK OF THE TRANSCENDENTAL DIALECTIC CHAPTER I THE PARALOGISMS OF PURE REASON A logical paralogism is a syllogism which is fallacious in form, be its content what it may. A transcendental paralogism is one in which there is a transcendental ground, constraining us to draw a formally invalid conclusion. Such a fallacy is P 329 therefore grounded in the nature of human reason, and gives rise to an illusion which cannot be avoided, although it may, indeed, be rendered harmless. We now come to a concept which was not included in the general list of transcendental concepts but which must yet be counted as belonging to that list, without, however, in the least altering it or declaring it defective. This is the concept or, if the term be preferred, the judgment, 'I think'. As is easily seen, this is the vehicle of all concepts, and therefore also of transcendental concepts, and so is always included in the conceiving of these latter, and is itself transcendental. But it can have no special designation, because it serves only to introduce all our thought, as belonging to consciousness. Meanwhile, however free it be of empirical admixture (impressions of the senses), it yet enables us to distinguish, through the nature of our faculty of representation, two kinds of objects. 'I', as thinking, am an object of inner sense, and am called 'soul'. That which is an object of the outer senses is called 'body'. Accordingly the expression 'I', as a thinking being, signifies the object of that psychology which may be entitled the 'rational doctrine of the soul', inasmuch as I am not here seeking to learn in regard to the soul anything more than can be inferred, independently of all experience (which determines me more specifically and in concreto), from this concept 'I', so far as it is present in all thought. The rational doctrine of the soul is really an undertaking of this kind; for if in this science the least empirical element of my thought, or any special perception of my inner state, were intermingled with the grounds of knowledge, it would no longer be a rational but an empirical doctrine of the soul. Thus we have here what professes to be a science built upon the single proposition 'I think'. Whether this claim be well or ill grounded, we may, very fittingly, in accordance with the nature of a transcendental philosophy, proceed to investigate. The reader must not object that this proposition, which expresses the perception of the self, contains an inner experience, and that the rational doctrine of the soul founded upon it is never pure and is therefore to that extent based upon an empirical principle. For this inner perception is nothing more than the mere apperception 'I think', by which even P 330 transcendental concepts are made possible; what we assert in them is 'I think substance, cause', etc. For inner experience in general and its possibility, or perception in general and its relation to other perception, in which no special distinction or empirical determination is given, is not to be regarded as empirical knowledge but as knowledge of the empirical in general, and has to be reckoned with the investigation of the possibility of any and every experience, which is certainly a transcendental enquiry. The least object of perception (for example, even pleasure or displeasure), if added to the universal representation of self-consciousness, would at once transform rational psychology into empirical psychology. 'I think' is, therefore, the sole text of rational psychology, and from it the whole of its teaching has to be developed. Obviously, if this thought is to be related to an object (myself), it can contain none but transcendental predicates of that object, since the least empirical predicate would destroy the rational purity of the science and its independence of all experience. All that is here required is that we follow the guidance of the categories, with this difference only, that since our starting- point is a given thing, 'I' as thinking being, we begin with the category of substance, whereby a thing in itself is represented, and so proceed backwards through the series, without, however, otherwise changing the order adopted in the table of the categories. The topic of the rational doctrine of the soul, from which everything else that it contains must be derived, is accordingly as follows: I The soul is substance. 2 As regards its quality it is simple. 3 As regards the different times in which it exists, it is numerically identical, that is, unity (not plurality). P 331 4 It is in relation to possible objects in space. All the concepts of pure psychology arise from these elements, simply by way of combination, without admission of any other principle. This substance, merely as object of inner sense, gives the concept of immateriality; as simple substance, that of incorruptibility; its identity, as intellectual substance, personality; all these three together, spirituality; while the relation to objects in space gives commercium with bodies, and so leads us to represent the thinking substance as the principle of life in matter, that is, as soul (anima), and as the ground of animality. This last, in turn, as limited by spirituality, gives the concept of immortality. In connection with these concepts we have four paralogisms of a transcendental psychology -- which is wrongly regarded as a science of pure reason -- concerning the nature of our thinking being. We can assign no other basis for this teaching than the simple, and in itself completely empty, representation 'I'; and we cannot even say that this is a concept, but only that it is a bare consciousness which accompanies all concepts. Through this I or he or it (the thing) which thinks, nothing further is represented than a transcendental subject of the thoughts = X. It is known only through the thoughts which are its predicates, and of it, apart from them, we cannot have any concept whatsoever, but can only revolve in a perpetual circle, since any judgment upon it has always already made use of its representation. ++ The reader who has difficulty in guessing the psychological meaning of these expressions taken in their transcendental abstractness, and in discovering why the last-mentioned attribute of the soul belongs to the category of existence, will find the terms sufficiently explained and justified in the sequel. Further, I have to apologise for the Latin expressions which, contrary to good taste, have usurped the place of their German equivalents, both in this section and in the work as a whole. My excuse is that I have preferred to lose somewhat in elegance of language rather than to increase, in however minor a degree, the reader's difficulties. P 331 And the reason why this inconvenience is inseparably bound up with it, is that consciousness in itself is not a representation distinguishing a particular object, but a form P 332 of representation in general, that is, of representation in so far as it is to be entitled knowledge; for it is only of knowledge that I can say that I am thereby thinking something. It must, on first thoughts, seem strange that the condition under which alone I think, and which is therefore merely a property of myself as subject, should likewise be valid for everything that thinks, and that on a seemingly empirical proposition we can presume to base an apodeictic and universal judgment, namely, that that which thinks must, in all cases, be constituted as the voice of self-consciousness declares it to be constituted in my own self. The reason is this: we must assign to things, necessarily and a priori, all the properties that constitute the conditions under which alone we think them. Now I cannot have any representation whatsoever of a thinking being, through any outer experience, but only through self-consciousness. Objects of this kind are, therefore, nothing more than the transference of this consciousness of mine to other things, which in this way alone can be represented as thinking beings. The proposition, 'I think', is, however, here taken only problematically, not in so far as it may contain perception of an existent (the Cartesian cogito, ergo sum), but in respect of its mere possibility, in order to see what properties applicable to its subject (be that subject actually existent or not) may follow from so simple a proposition. If our knowledge of thinking beings in general, by means of pure reason, were based on more than the cogito, if we likewise made use of observations concerning the play of our thoughts and the natural laws of the thinking self to be derived from these thoughts, there would arise an empirical psychology, which would be a kind of physiology of inner sense, capable perhaps of explaining the appearances of inner sense, but never of revealing such properties as do not in any way belong to possible experience (e.g. the properties of the simple), nor of yielding any apodeictic knowledge regarding the nature of thinking beings in general. It would not, therefore, be a rational psychology. Since the proposition 'I think' (taken problematically) contains the form of each and every judgment of the understanding and accompanies all categories as their vehicle, it is evident that the inferences from it admit only of a transcendental P 333 employment of the understanding. And since this employment excludes any admixture of experience, we cannot, after what has been shown above, entertain any favourable anticipations in regard to its methods of procedure. We therefore propose to follow it, with a critical eye, through all the predicaments of pure psychology. THE PARALOGISMS OF PURE REASON FIRST PARALOGISM: OF SUBSTANTIALITY That, the representation of which is the absolute subject of our judgments and cannot therefore be employed as determination of another thing, is substance. I, as a thinking being, am the absolute subject of all my possible judgments, and this representation of myself cannot be employed as predicate of any other thing. Therefore I, as thinking being (soul), am substance. Critique of the First Paralogism of Pure Psychology In the analytical part of the Transcendental Logic we have shown that pure categories, and among them that of substance, have in themselves no objective meaning, save in so far as they rest upon an intuition, and are applied to the manifold of this intuition, as functions of synthetic unity. In the absence of this manifold, they are merely functions of a judgment, without content. I can say of any and every thing that it is substance, in the sense that I distinguish it from mere predicates and determinations of things. Now in all our thought the 'I' is the subject, in which thoughts inhere only as determinations; and this 'I' cannot be employed as the determination of another thing. Everyone must, therefore, necessarily regard himself as substance, and thought as [consisting] only [in] accidents of his being, determinations of his state. But what use am I to make of this concept of a substance? That I, as a thinking being, persist for myself, and do not in any natural manner either arise or perish, can by no means be P 334 deduced from it. Yet there is no other use to which I can put the concept of the substantiality of my thinking subject, and apart from such use I could very well dispense with it. So far from being able to deduce these properties merely from the pure category of substance, we must, on the contrary, take our start from the permanence of an object given in experience as permanent. For only to such an object can the concept of substance be applied in a manner that is empirically serviceable. In the above proposition, however, we have not taken as our basis any experience; the inference is merely from the concept of the relation which all thought has to the 'I' as the common subject in which it inheres. Nor should we, in resting it upon experience, be able, by any sure observation, to demonstrate such permanence. The 'I' is indeed in all thoughts, but there is not in this representation the least trace of intuition, distinguishing the 'I' from other objects of intuition. Thus we can indeed perceive that this representation is invariably present in all thought, but not that it is an abiding and continuing intuition, wherein the thoughts, as being transitory, give place to one another. It follows, therefore, that the first syllogism of transcendental psychology, when it puts forward the constant logical subject of thought as being knowledge of the real subject in which the thought inheres, is palming off upon us what is a mere pretence of new insight. We do not have, and cannot have, any knowledge whatsoever of any such subject. Consciousness is, indeed, that which alone makes all representations to be thoughts, and in it, therefore, as the transcendental subject, all our perceptions must be found; but beyond this logical meaning of the 'I', we have no knowledge of the subject in itself, which as substratum underlies this 'I', as it does all thoughts. The proposition, 'The soul is substance', may, however, quite well be allowed to stand, if only it be recognised that this concept [of the soul as substance] does not carry us a single step further, and so cannot yield us any of the usual deductions of the pseudo-rational doctrine of the soul, as, for instance, the everlasting duration of the human soul in all changes and even in death -- if, that is to say, we recognise that this concept signifies a substance only in idea, not in reality. P 335 SECOND PARALOGISM: OF SIMPLICITY That, the action of which can never be regarded as the concurrence of several things acting, is simple. Now the soul, or the thinking 'I', is such a being. Therefore, etc. Critique of the Second Paralogism of Transcendental Psychology This is the Achilles of all dialectical inferences in the pure doctrine of the soul. It is no mere sophistical play, contrived by a dogmatist in order to impart to his assertions a superficial plausibility, but an inference which appears to withstand even the keenest scrutiny and the most scrupulously exact investigation. It is as follows. Every composite substance is an aggregate of several substances, and the action of a composite, or whatever inheres in it as thus composite, is an aggregate of several actions or accidents, distributed among the plurality of the substances. Now an effect which arises from the concurrence of many acting substances is indeed possible, namely, when this effect is external only (as, for instance, the motion of a body is the combined motion of all its parts). But with thoughts, as internal accidents belonging to a thinking being, it is different. For suppose it be the composite that thinks: then every part of it would be a part of the thought, and only all of them taken together would contain the whole thought. But this cannot consistently be maintained. For representations (for instance, the single words of a verse), distributed among different beings, never make up a whole thought (a verse), and it is therefore impossible that a thought should inhere in what is essentially composite. It is therefore possible only in a single substance, which, not being an aggregate of many, is absolutely simple. ++ This proof can very easily be given the customary syllogistic correctness of form. But for my purpose it is sufficient to have made clear, though in popular fashion, the bare ground of proof. P 335 The so-called nervus probandi of this argument lies in the proposition, that if a multiplicity of representations are to form a single representation, they must be contained in the P 336 absolute unity of the thinking subject. No one, however, can prove this proposition from concepts. For how should he set about the task of achieving this? The proposition, 'A thought can only be the effect of the absolute unity of the thinking being', cannot be treated as analytic. For the unity of the thought, which consists of many representations, is collective, and as far as mere concepts can show, may relate just as well to the collective unity of different substances acting together (as the motion of a body is the composite motion of all its parts) as to the absolute unity of the subject. Consequently, the necessity of presupposing, in the case of a composite thought, a simple substance, cannot be demonstrated in accordance with the principle of identity. Nor will anyone venture to assert that the proposition allows of being known synthetically and completely a priori from mere concepts -- not, at least, if he understands the ground of the possibility of a priori synthetic propositions, as above explained. It is likewise impossible to derive this necessary unity of the subject, as a condition of the possibility of every thought, from experience. For experience yields us no knowledge of necessity, apart even from the fact that the concept of absolute unity is quite outside its province. Whence then are we to derive this proposition upon which the whole psychological syllogism depends? It is obvious that, if I wish to represent to myself a thinking being, I must put myself in his place, and thus substitute, as it were, my own subject for the object I am seeking to consider (which does not occur in any other kind of investigation), and that we demand the absolute unity of the subject of a thought, only because otherwise we could not say, 'I think' (the manifold in a representation). For although the whole of the thought could be divided and distributed among many subjects, the subjective 'I' can never be thus divided and distributed, and it is this 'I' that we presuppose in all thinking. Here again, as in the former paralogism, the formal proposition of apperception, 'I think', remains the sole ground to which rational psychology can appeal when it thus ventures upon an extension of its knowledge. This proposition, however, is not itself an experience, but the form of apperception, P 337 which belongs to and precedes every experience; and as such it must always be taken only in relation to some possible knowledge, as a merely subjective condition of that knowledge. We have no right to transform it into a condition of the possibility of a knowledge of objects, that is, into a concept of thinking being in general. For we are not in a position to represent such being to ourselves save by putting ourselves, with the formula of our consciousness, in the place of every other intelligent being. Nor is the simplicity of myself (as soul) really inferred from the proposition, 'I think'; it is already involved in every thought. The proposition, 'I am simple', must be regarded as an immediate expression of apperception, just as what is referred to as the Cartesian inference, cogito, ergo sum, is really a tautology, since the cogito (sum cogitans) asserts my existence immediately. 'I am simple' means nothing more than that this representation, 'I', does not contain in itself the least manifoldness and that it is absolute (although merely logical) unity. Thus the renowned psychological proof is founded merely on the indivisible unity of a representation, which governs only the verb in its relation to a person. It is obvious that in attaching 'I' to our thoughts we designate the subject of inherence only transcendentally, without noting in it any quality whatsoever -- in fact, without knowing anything of it either by direct acquaintance or otherwise. It means a something in general (transcendental subject), the representation of which must, no doubt, be simple, if only for the reason that there is nothing determinate in it. Nothing, indeed, can be represented that is simpler than that which is represented through the concept of a mere something. But the simplicity of the representation of a subject is not eo ipso knowledge of the simplicity of the subject itself, for we abstract altogether from its properties when we designate it solely by the entirely empty expression 'I', an expression which I can apply to every thinking subject. This much, then, is certain, that through the 'I', I always P 338 entertain the thought of an absolute, but logical, unity of the subject (simplicity). It does not, however, follow that I thereby know the actual simplicity of my subject. The proposition, 'I am substance', signifies, as we have found, nothing but the pure category, of which I can make no use (empirically) in concreto; and I may therefore legitimately say: 'I am a simple substance', that is, a substance the representation of which never contains a synthesis of the manifold. But this concept, as also the proposition, tells us nothing whatsoever in regard to myself as an object of experience, since the concept of substance is itself used only as a function of synthesis, without any underlying intuition, and therefore without an object. It concerns only the condition of our knowledge; it does not apply to any assignable object. We will test the supposed usefulness of the proposition by an experiment. Everyone must admit that the assertion of the simple nature of the soul is of value only in so far as I can thereby distinguish this subject from all matter, and so can exempt it from the dissolution to which matter is always liable. This is indeed, strictly speaking, the only use for which the above proposition is intended, and is therefore generally expressed as 'The soul is not corporeal'. If, then, I can show that, although we allow full objective validity -- the validity appropriate to a judgment of pure reason derived solely from pure categories -- to this cardinal proposition of the rational doctrine of the soul (that is, that everything which thinks is a simple substance), we still cannot make the least use of this proposition in regard to the question of its dissimilarity from or relation to matter, this will be the same as if I had relegated this supposed psychological insight to the field of mere ideas, without any real objective use. In the Transcendental Aesthetic we have proved, beyond all question, that bodies are mere appearances of our outer sense and not things in themselves. We are therefore justified in saying that our thinking subject is not corporeal; in other words, that, inasmuch as it is represented by us as object of inner sense, it cannot, in so far as it thinks, be an object of outer sense, that is, an appearance in space. This is equivalent to saying that thinking beings, as such, can never be found by us among outer appearances, and that their thoughts, consciousness, P 339 desires, etc. , cannot be outwardly intuited. All these belong to inner sense. This argument does, in fact, seem to be so natural and so popular that even the commonest understanding appears to have always relied upon it, and thus already, from the earliest times, to have regarded souls as quite different entities from their bodies. But although extension, impenetrability, cohesion, and motion -- in short, everything which outer senses can give us -- neither are nor contain thoughts, feeling, desire, or resolution, these never being objects of outer intuition, nevertheless the something which underlies the outer appearances and which so affects our sense that it obtains the representations of space, matter, shape, etc. , may yet, when viewed as noumenon (or better, as transcendental object), be at the same time the subject of our thoughts. That the mode in which our outer sense is thereby affected gives us no intuition of representations, will, etc. , but only of space and its determinations, proves nothing to the contrary. For this something is not extended, nor is it impenetrable or composite, since all these predicates concern only sensibility and its intuition, in so far as we are affected by certain (to us otherwise unknown) objects. By such statements we are not, however, enabled to know what kind of an object it is, but only to recognise that if it be considered in itself, and therefore apart from any relation to the outer senses, these predicates of outer appearances cannot be assigned to it. On the other hand, the predicates of inner sense, representations and thought, are not inconsistent with its nature. Accordingly, even granting the human soul to be simple in nature, such simplicity by no means suffices to distinguish it from matter, in respect of the substratum of the latter -- if, that is to say, we consider matter, as indeed we ought to, as mere appearance. If matter were a thing in itself, it would, as a composite being, be entirely different from the soul, as a simple being. But matter is mere outer appearance, the substratum of which cannot be known through any predicate that we can assign to it. I can therefore very well admit the possibility that it is in itself simple, although owing to the manner in which it affects our senses it produces in us the intuition of the extended and so of P 340 the composite. I may further assume that the substance which in relation to our outer sense possesses extension is in itself the possessor of thoughts, and that these thoughts can by means of its own inner sense be consciously represented. In this way, what in one relation is entitled corporeal would in another relation be at the same time a thinking being, whose thoughts we cannot intuit, though we can indeed intuit their signs in the [field of] appearance. Accordingly, the thesis that only souls (as particular kinds of substances) think, would have to be given up; and we should have to fall back on the common expression that men think, that is, that the very same being which, as outer appearance, is extended, is (in itself) internally a subject, and is not composite, but is simple and thinks. But, without committing ourselves in regard to such hypotheses, we can make this general remark. If I understand by soul a thinking being in itself, the question whether or not it is the same in kind as matter -- matter not being a thing in itself, but merely a species of representations in us -- is by its very terms illegitimate. For it is obvious that a thing in itself is of a different nature from the determinations which constitute only its state. If, on the other hand, we compare the thinking 'I' not with matter but with the intelligible that lies at the basis of the outer appearance which we call matter, we have no knowledge whatsoever of the intelligible, and therefore are in no position to say that the soul is in any inward respect different from it. The simple consciousness is not, therefore, knowledge of the simple nature of the self as subject, such as might enable us to distinguish it from matter, as from a composite being. If, therefore, in the only case in which this concept can be of service, namely, in the comparison of myself with objects of outer experience, it does not suffice for determining what is specific and distinctive in the nature of the self, then though we may still profess to know that the thinking 'I', the soul (a name for the transcendental object of inner sense), is simple, such a way of speaking has no sort of application to real objects, and therefore cannot in the least extend our knowledge. P 341 Thus the whole of rational psychology is involved in the collapse of its main support. Here as little as elsewhere can we hope to extend our knowledge through mere concepts -- still less by means of the merely subjective form of all our concepts, consciousness -- in the absence of any relation to possible experience. For [as we have thus found], even the fundamental concept of a simple nature is such that it can never be met with in any experience, and such, therefore, that there is no way of attaining to it, as an objectively valid concept. THIRD PARALOGISM: OF PERSONALITY That which is conscious of the numerical identity of itself at different times is in so far a person. Now the soul is conscious, etc. Therefore it is a person. Critique of the Third Paralogism of Transcendental Psychology If I want to know through experience, the numerical identity of an external object, I shall pay heed to that permanent element in the appearance to which as subject everything else is related as determination, and note its identity throughout the time in which the determinations change. Now I am an object of inner sense, and all time is merely the form of inner sense. Consequently, I refer each and all of my successive determinations to the numerically identical self, and do so throughout time, that is, in the form of the inner intuition of myself. This being so, the personality of the soul has to be regarded not as inferred but as a completely identical proposition of self-consciousness in time; and this, indeed, is why it is valid a priori. For it really says nothing more than that in the whole time in which I am conscious of myself, I am conscious of this time as belonging to the unity of myself; and it comes to the same whether I say that this whole time is in me, as individual unity, or that I am to be found as numerically identical in all this time. In my own consciousness, therefore, identity of person is unfailingly met with. But if I view myself from the standpoint of another person (as object of his outer intuition), it is this P 342 outer observer who first represents me in time, for in the apperception time is represented, strictly speaking, only in me. Although he admits, therefore, the 'I', which accompanies, and indeed with complete identity, all representations at all times in my consciousness, he will draw no inference from this to the objective permanence of myself. For just as the time in which the observer sets me is not the time of my own but of his sensibility, so the identity which is necessarily bound up with my consciousness is not therefore bound up with his, that is, with the consciousness which contains the outer intuition of my subject. The identity of the consciousness of myself at different times is therefore only a formal condition of my thoughts and their coherence, and in no way proves the numerical identity of my subject. Despite the logical identity of the 'I', such a change may have occurred in it as does not allow of the retention of its identity, and yet we may ascribe to it the same-sounding 'I', which in every different state, even in one involving change of the [thinking] subject, might still retain the thought of the preceding subject and so hand it over to the subsequent subject. Although the dictum of certain ancient schools, that everything in the world is in a flux and nothing is permanent and abiding, cannot be reconciled with the admission of substances, it is not refuted by the unity of self-consciousness. ++ An elastic ball which impinges on another similar ball in a straight line communicates to the latter its whole motion, and therefore its whole state (that is, if we take account only of the positions in space). If, then, in analogy with such bodies, we postulate substances such that the one communicates to the other representations together with the consciousness of them, we can conceive a whole series of substances of which the first transmits its state together with its consciousness to the second, the second its own state with that of the preceding substance to the third, and this in turn the states of all the preceding substances together with its own consciousness and with their consciousness to another. The last substance would then be conscious of all the states of the previously changed substances, as being its own states, because they would have been transferred to it together with the consciousness of them. And yet it would not have been one and the same person in all these states. P 343 For we are unable from our own consciousness to determine whether, as souls, we are permanent or not. Since we reckon as belonging to our identical self only that of which we are conscious, we must necessarily judge that we are one and the same throughout the whole time of which we are conscious. We cannot, however, claim that this judgment would be valid from the standpoint of an outside observer. For since the only permanent appearance which we encounter in the soul is the representation 'I' that accompanies and connects them all, we are unable to prove that this 'I', a mere thought, may not be in the same state of flux as the other thoughts which, by means of it, are linked up with one another. It is indeed strange that personality, and its presupposition, permanence, and therefore the substantiality of the soul, should have to be proved at this stage and not earlier. For could we have presupposed these latter [permanence and substantiality], there would follow, not indeed the continuance of consciousness, yet at least the possibility of a continuing consciousness in an abiding subject, and that is already sufficient for personality. For personality does not itself at once cease because its activity is for a time interrupted. This permanence, however, is in no way given prior to that numerical identity of our self which we infer from identical apperception, but on the contrary is inferred first from the numerical identity. (If the argument proceeded aright, the concept of substance, which is applicable only empirically, would first be brought in after such proof of numerical identity. ) Now, since this identity of person [presupposing, as it does, numerical identity] in nowise follows from the identity of the 'I' in the consciousness of all the time in which I know myself, we could not, earlier in the argument, have founded upon it the substantiality of the soul. Meanwhile we may still retain the concept of personality just as we have retained the concept of substance and of the simple -- in so far as it is merely transcendental, that is, concerns the unity of the subject, otherwise unknown to us, in the determinations of which there is a thoroughgoing connection through apperception. Taken in this way, the concept is necessary for practical employment and is sufficient for P 344 such use; but we can never parade it as an extension of our self-knowledge through pure reason, and as exhibiting to us from the mere concept of the identical self an unbroken continuance of the subject. For this concept revolves perpetually in a circle, and does not help us in respect to any question which aims at synthetic knowledge. What matter may be as a thing in itself (transcendental object) is completely unknown to us, though, owing to its being represented as something external, its permanence as appearance can indeed be observed. But if I want to observe the mere 'I' in the change of all representations, I have no other correlatum to use in my comparisons except again myself, with the universal conditions of my consciousness. Consequently, I can give none but tautological answers to all questions, in that I substitute my concept and its unity for the properties which belong to myself as object, and so take for granted that which the questioner has desired to know. THE FOURTH PARALOGISM: OF IDEALITY (IN REGARD TO OUTER RELATION) That, the existence of which can only be inferred as a cause of given perceptions, has a merely doubtful existence. Now all outer appearances are of such a nature that their existence is not immediately perceived, and that we can only infer them as the cause of given perceptions. Therefore the existence of all objects of the outer senses is doubtful. This uncertainty I entitle the ideality of outer appearances, and the doctrine of this ideality is called idealism, as distinguished from the counter-assertion of a possible certainty in regard to objects of outer sense, which is called dualism. Critique of the Fourth Paralogism of Transcendental Psychology Let us first examine the premisses. We are justified, [it is argued], in maintaining that only what is in ourselves can be perceived immediately, and that my own existence is the sole object of a mere perception. The existence, therefore, of an actual object outside me (if this word 'me' be taken in the P 345 intellectual [not in the empirical] sense) is never given directly in perception. Perception is a modification of inner sense, and the existence of the outer object can be added to it only in thought, as being its outer cause, and accordingly as being inferred. For the same reason, Descartes was justified in limiting all perception, in the narrowest sense of that term, to the proposition, 'I, as a thinking being, exist. ' Obviously, since what is without is not in me, I cannot encounter it in my apperception, nor therefore in any perception, which, properly regarded, is merely the determination of apperception. I am not, therefore, in a position to perceive external things, but can only infer their existence from my inner perception, taking the inner perception as the effect of which something external is the proximate cause. Now the inference from a given effect to a determinate cause is always uncertain, since the effect may be due to more than one cause. Accordingly, as regards the relation of the perception to its cause, it always remains doubtful whether the cause be internal or external; whether, that is to say, all the so-called outer perceptions are not a mere play of our inner sense, or whether they stand in relation to actual external objects as their cause. At all events, the existence of the latter is only inferred, and is open to all the dangers of inference, whereas the object of inner sense (I myself with all my representations) is immediately perceived, and its existence does not allow of being doubted. The term 'idealist' is not, therefore, to be understood as applying to those who deny the existence of external objects of the senses, but only to those who do not admit that their existence is known through immediate perception, and who therefore conclude that we can never, by way of any possible experience, be completely certain as to their reality. Before exhibiting our paralogism in all its deceptive illusoriness, I have first to remark that we must necessarily distinguish two types of idealism, the transcendental and the empirical. By transcendental idealism I mean the doctrine that appearances are to be regarded as being, one and all, representations only, not things in themselves, and that time and space are therefore only sensible forms of our intuition, not determinations given as existing by themselves, nor conditions of objects viewed as things in themselves. To this idealism P 346 there is opposed a transcendental realism which regards time and space as something given in themselves, independently of our sensibility. The transcendental realist thus interprets outer appearances (their reality being taken as granted) as things-in-themselves, which exist independently of us and of our sensibility, and which are therefore outside us -- the phrase 'outside us' being interpreted in conformity with pure concepts of understanding. It is, in fact, this transcendental realist who afterwards plays the part of empirical idealist. After wrongly supposing that objects of the senses, if they are to be external, must have an existence by themselves, and independently of the senses, he finds that, judged from this point of view, all our sensuous representations are inadequate to establish their reality. The transcendental idealist, on the other hand, may be an empirical realist or, as he is called, a dualist; that is, he may admit the existence of matter without going outside his mere self-consciousness, or assuming anything more than the certainty of his representations, that is, the cogito, ergo sum. For he considers this matter and even its inner possibility to be appearance merely; and appearance, if separated from our sensibility, is nothing. Matter is with him, therefore, only a species of representations (intuition), which are called external, not as standing in relation to objects in themselves external, but because they relate perceptions to the space in which all things are external to one another, while yet the space itself is in us. From the start, we have declared ourselves in favour of this transcendental idealism; and our doctrine thus removes all difficulty in the way of accepting the existence of matter on the unaided testimony of our mere self-consciousness, or of declaring it to be thereby proved in the same manner as the existence of myself as a thinking being is proved. There can be no question that I am conscious of my representations; these representations and I myself, who have the representations, therefore exist. External objects (bodies), however, are mere appearances, and are therefore nothing but a species of my representations, the objects of which are something only through these representations. Apart from them they are nothing. Thus external things exist as well as I myself, and P 347 both indeed, upon the immediate witness of my self-consciousness. The only difference is that the representation of myself, as the thinking subject, belongs to inner sense only, while the representations which mark extended beings belong also to outer sense. In order to arrive at the reality of outer objects I have just as little need to resort to inference as I have in regard to the reality of the object of my inner sense, that is, in regard to the reality of my thoughts. For in both cases alike the objects are nothing but representations, the immediate perception (consciousness) of which is at the same time a sufficient proof of their reality. The transcendental idealist is, therefore, an empirical realist, and allows to matter, as appearance, a reality which does not permit of being inferred, but is immediately perceived. Transcendental realism, on the other hand, inevitably falls into difficulties, and finds itself obliged to give way to empirical idealism, in that it regards the objects of outer sense as something distinct from the senses themselves, treating mere appearances as self-subsistent beings, existing outside us. On such a view as this, however clearly we may be conscious of our representation of these things, it is still far from certain that, if the representation exists, there exists also the object corresponding to it. In our system, on the other hand, these external things, namely matter, are in all their configurations and alterations nothing but mere appearances, that is, representations in us, of the reality of which we are immediately conscious. Since, so far as I know, all psychologists who adopt empirical idealism are transcendental realists, they have certainly proceeded quite consistently in ascribing great importance to empirical idealism, as one of the problems in regard to which the human mind is quite at a loss how to proceed. For if we regard outer appearances as representations produced in us by their objects, and if these objects be things existing in themselves outside us, it is indeed impossible to see how we can come to know the existence of the objects otherwise than by inference from the effect to the cause; and this being so, it must always remain doubtful whether the cause in question be in us or outside us. We can indeed admit that something, which P 348 may be (in the transcendental sense) outside us, is the cause of our outer intuitions, but this is not the object of which we are thinking in the representations of matter and of corporeal things; for these are merely appearances, that is, mere kinds of representation, which are never to be met with save in us, and the reality of which depends on immediate consciousness, just as does the consciousness of my own thoughts. The transcendental object is equally unknown in respect to inner and to outer intuition. But it is not of this that we are here speaking, but of the empirical object, which is called an external object if it is represented in space, and an inner object if it is represented only in its time-relations. Neither space nor time, however, is to be found save in us. The expression 'outside us' is thus unavoidably ambiguous in meaning, sometimes signifying what as thing in itself exists apart from us, and sometimes what belongs solely to outer appearance. In order, therefore, to make this concept, in the latter sense -- the sense in which the psychological question as to the reality of our outer intuition has to be understood -- quite unambiguous, we shall distinguish empirically external objects from those which may be said to be external in the transcendental sense, by explicitly entitling the former 'things which are to be found in space'. Space and time are indeed a priori representations, which dwell in us as forms of our sensible intuition, before any real object, determining our sense through sensation, has enabled us to represent the object under those sensible relations. But the material or real element, the something which is to be intuited in space, necessarily presupposes perception. Perception exhibits the reality of something in space; and in the absence of perception no power of imagination can invent and produce that something. It is sensation, therefore, that indicates a reality in space or in time, according as it is related to the one or to the other mode of sensible intuition. (Once sensation is given -- if referred to an object in general, though not as determining that object, it is entitled perception -- thanks to its manifoldness we can picture in imagination many objects which have no empirical place in space or time outside the imagination. ) P 349 This admits of no doubt; whether we take pleasure and pain, or the sensations of the outer senses, colours, heat, etc. , perception is that whereby the material required to enable us to think objects of sensible intuition must first be given. This perception, therefore (to consider, for the moment, only outer intuitions), represents something real in space. For, in the first place, while space is the representation of a mere possibility of coexistence, perception is the representation of a reality. Secondly, this reality is represented in outer sense, that is, in space. Thirdly, space is itself nothing but mere representation, and therefore nothing in it can count as real save only what is represented in it; and conversely, what is given in it, that is, represented through perception, is also real in it. For if it were not real, that is, immediately given through empirical intuition, it could not be pictured in imagination, since what is real in intuitions cannot be invented a priori. All outer perception, therefore, yields immediate proof of something real in space, or rather is the real itself. In this sense empirical realism is beyond question; that is, there corresponds to our outer intuitions something real in space. Space itself, with all its appearances, as representations, is, indeed, only in me, but nevertheless the real, that is, the material of all objects of outer intuition, is actually given in this space, independently of all imaginative invention. Also, it is impossible that in this space anything outside us (in the transcendental sense) should be given, space itself being nothing outside our sensibility. Even the most rigid idealist cannot, therefore, require a proof that the object outside us (taking 'outside' in the strict [transcendental] sense) corresponds to our perception. ++ We must give full credence to this paradoxical but correct proposition, that there is nothing in space save what is represented in it. For space is itself nothing but representation, and whatever is in it must therefore be contained in the representation. Nothing whatsoever is in space, save in so far as it is actually represented in it. It is a proposition which must indeed sound strange, that a thing can exist only in the representation of it, but in this case the objection falls, inasmuch as the things with which we are here concerned are not things in themselves, but appearances only, that is, representations. P 349 For if there be any such object, it could not be P 350 represented and intuited as outside us, because such representation and intuition presuppose space, and reality in space, being the reality of a mere representation, is nothing other than perception itself. The real of outer appearances is therefore real in perception only, and can be real in no other way. From perceptions knowledge of objects can be generated, either by mere play of imagination or by way of experience; and in the process there may, no doubt, arise illusory representations to which the objects do not correspond, the deception being attributable sometimes to a delusion of imagination (in dreams) and sometimes to an error of judgment in so-called sense-deception). To avoid such deceptive illusion, we have to proceed according to the rule: Whatever is connected with a perception according to empirical laws, is actual. But such deception, as well as the provision against it, affects idealism quite as much as dualism, inasmuch as we are concerned only with the form of experience. Empirical idealism, and its mistaken questionings as to the objective reality of our outer perceptions, is already sufficiently refuted, when it has been shown that outer perception yields immediate proof of something actual in space, and that this space, although in itself only a mere form of representations, has objective reality in relation to all outer appearances, which also are nothing else than mere representations; and when it has likewise been shown that in the absence of perception even imagining and dreaming are not possible, and that our outer senses, as regards the data from which experience can arise, have therefore their actual corresponding objects in space. The dogmatic idealist would be one who denies the existence of matter, the sceptical idealist one who doubts its existence, because holding it to be incapable of proof. The former must base his view on supposed contradictions in the possibility of there being such a thing as matter at all -- a view with which we have not yet been called upon to deal. The following section on dialectical inferences, which represents reason as in strife with itself in regard to the concepts which it makes for itself of the possibility of what belongs to the P 351 connection of experience, will remove this difficulty. The sceptical idealist, however, who merely challenges the ground of our assertion and denounces as insufficiently justified our conviction of the existence of matter, which we thought to base on immediate perception, is a benefactor of human reason in so far as he compels us, even in the smallest advances of ordinary experience, to keep on the watch, lest we consider as a well-earned possession what we perhaps obtain only illegitimately. We are now in a position to appreciate the value of these idealist objections. Unless we mean to contradict ourselves in our commonest assertions, they drive us by main force to view all our perceptions, whether we call them inner or outer, as a consciousness only of what is dependent on our sensibility. They also compel us to view the outer objects of these perceptions not as things in themselves, but only as representations, of which, as of every other representation, we can become immediately conscious, and which are entitled outer because they depend on what we call 'outer sense', whose intuition is space. Space itself, however, is nothing but an inner mode of representation in which certain perceptions are connected with one another. If we treat outer objects as things in themselves, it is quite impossible to understand how we could arrive at a knowledge of their reality outside us, since we have to rely merely on the representation which is in us. For we cannot be sentient [of what is] outside ourselves, but only [of what is] in us, and the whole of our self-consciousness therefore yields nothing save merely our own determinations. Sceptical idealism thus constrains us to have recourse to the only refuge still open, namely, the ideality of all appearances, a doctrine which has already been established in the Transcendental Aesthetic independently of these consequences, which we could not at that stage foresee. If then we ask, whether it follows that in the doctrine of the soul dualism alone is tenable, we must answer: 'Yes, certainly; but dualism only in the empirical sense'. That is to say, in the connection of experience matter, as substance in the [field of] appearance, is really given to outer sense, just as the thinking 'I', also as substance in the [field of] appearance, is given to inner sense. Further, appearances in both fields P 352 must be connected with each other according to the rules which this category introduces into that connection of our outer as well as of our inner perceptions whereby they constitute one experience. If, however, as commonly happens, we seek to extend the concept of dualism, and take it in the transcendental sense, neither it nor the two counter-alternatives -- pneumatism on the one hand, materialism on the other -- would have any sort of basis, since we should then have misapplied our concepts, taking the difference in the mode of representing objects, which, as regards what they are in themselves, still remain unknown to us, as a difference in the things themselves. Though the 'I', as represented through inner sense in time, and objects in space outside me, are specifically quite distinct appearances, they are not for that reason thought as being different things. Neither the transcendental object which underlies outer appearances nor that which underlies inner intuition, is in itself either matter or a thinking being, but a ground (to us unknown) of the appearances which supply to us the empirical concept of the former as well as of the latter mode of existence. If then, as this critical argument obviously compels us to do, we hold fast to the rule above established, and do not push our questions beyond the limits within which possible experience can present us with its object, we shall never dream of seeking to inform ourselves about the objects of our senses as they are in themselves, that is, out of all relation to the senses. But if the psychologist takes appearances for things in themselves, and as existing in and by themselves, then whether he be a materialist who admits into his system nothing but matter alone, or a spiritualist who admits only thinking beings (that is, beings with the form of our inner sense), or a dualist who accepts both, he will always, owing to this misunderstanding, be entangled in pseudo-rational speculations as to how that which is not a thing in itself, but only the appearance of a thing in general, can exist by itself. Consideration of Pure Psychology as a whole, in view of these Paralogisms If we compare the doctrine of the soul as the physiology of inner sense, with the doctrine of the body as a physiology of P 353 the object of the outer senses, we find that while in both much can be learnt empirically, there is yet this notable difference In the latter science much that is a priori can be synthetically known from the mere concept of an extended impenetrable being, but in the former nothing whatsoever that is a priori can be known synthetically from the concept of a thinking being. The cause is this. Although both are appearances, the appearance to outer sense has something fixed or abiding which supplies a substratum as the basis of its transitory determinations and therefore a synthetic concept, namely, that of space and of an appearance in space; whereas time, which is the sole form of our inner intuition, has nothing abiding, and therefore yields knowledge only of the change of determinations, not of any object that can be thereby determined. For in what we entitle 'soul', everything is in continual flux and there is nothing abiding except (if we must so express ourselves) the 'I', which is simple solely because its representation has no content, and therefore no manifold, and for this reason seems to represent, or (to use a more correct term) denote, a simple object. In order that it should be possible, by pure reason, to obtain knowledge of the nature of a thinking being in general, this 'I' would have to be an intuition which, in being presupposed in all thought (prior to all experience), might as intuition yield a priori synthetic propositions. This 'I' is, however, as little an intuition as it is a concept of any object; it is the mere form of consciousness, which can accompany the two kinds of representation and which is in a position to elevate them to the rank of knowledge only in so far as something else is given in intuition which provides material for a representation of an object. Thus the whole of rational psychology, as a science surpassing all powers of human reason, proves abortive, and nothing is left for us but to study our soul under the guidance of experience, and to confine ourselves to those questions which do not go beyond the limits within which a content can be provided for them by possible inner experience. But although rational psychology cannot be used to extend knowledge, and when so employed is entirely made up of value, if it is taken as nothing more than a critical treatment P 354 of our dialectical inferences, those that arise from the common and natural reason of men. Why do we have resort to a doctrine of the soul founded exclusively on pure principles of reason? Beyond all doubt, chiefly in order to secure our thinking self against the danger of materialism. This is achieved by means of the pure concept of our thinking self which we have just given. For by this teaching so completely are we freed from the fear that on the removal of matter all thought, and even the very existence of thinking beings, would be destroyed, that on the contrary it is clearly shown, that if I remove the thinking subject the whole corporeal world must at once vanish: it is nothing save an appearance in the sensibility of our subject and a mode of its representations. I admit that this does not give me any further knowledge of the properties of this thinking self, nor does it enable me to determine its permanence or even that it exists independently of what we may conjecture to be the transcendental substratum of outer appearances; for the latter is just as unknown to me as is the thinking self. But it is nevertheless possible that I may find cause, on other than merely speculative grounds, to hope for an independent and continuing existence of my thinking nature, throughout all possible change of my state. In that case much will already have been gained if, while freely confessing my own ignorance, I am yet in a position to repel the dogmatic assaults of a speculative opponent, and to show him that he can never know more of the nature of the self in denying the possibility of my expectations than I can know in clinging to them. Three other dialectical questions, constituting the real goal of rational psychology, are grounded on this transcendental illusion in our psychological concepts, and cannot be decided except by means of the above enquiries: namely (1) of the possibility of the communion of the soul with an organised body, i.e. concerning animality and the state of the soul in the life of man; (2) of the beginning of this communion, that is, of the soul in and before birth; (3) of the end of this communion, that is, of the soul in and after death (the question of immortality). P 355 Now I maintain that all the difficulties commonly found in these questions, and by means of which, as dogmatic objections, men seek to gain credit for a deeper insight into the nature of things than any to which the ordinary understanding can properly lay claim, rest on a mere delusion by which they hypostatise what exists merely in thought, and take it as a real object existing, in the same character, outside the thinking subject. In other words, they regard extension, which is nothing but appearance, as a property of outer things that subsists even apart from our sensibility, and hold that motion is due to these things and really occurs in and by itself, apart from our senses. For matter, the communion of which with the soul arouses so much questioning, is nothing but a mere form, or a particular way of representing an unknown object by means of that intuition which is called outer sense. There may well be something outside us to which this appearance, which we call matter, corresponds; in its character of appearance it is not, however, outside us, but is only a thought in us, although this thought, owing to the above-mentioned outer sense, represents it as existing outside us. Matter, therefore, does not mean a kind of substance quite distinct and heterogeneous from the object of inner sense (the soul), but only the distinctive nature of those appearances of objects -- in themselves unknown to us -- the representations of which we call outer as compared with those which we count as belonging to inner sense, although like all other thoughts these outer representations belong only to the thinking subject. They have, indeed, this deceptive property that, representing objects in space, they detach themselves as it were from the soul and appear to hover outside it. Yet the very space in which they are intuited is nothing but a representation, and no counterpart of the same quality is to be found outside the soul. Consequently, the question is no longer of the communion of the soul with other known substances of a different kind outside us, but only of the connection of the representations of inner sense with the modifications of our outer sensibility -- as to how these can be so connected with each other according to settled laws that they exhibit the unity of a coherent experience. As long as we take inner and outer appearances together as mere representations in experience, we find nothing absurd P 356 and strange in the association of the two kinds of senses. But as soon as we hypostatise outer appearances and come to regard them not as representations but as things existing by themselves outside us, with the same quality as that with which they exist in us, and as bringing to bear on our thinking subject the activities which they exhibit as appearances in relation to each other, then the efficient causes outside us assume a character which is irreconcilable with their effects in us. For the cause relates only to outer sense, the effect to inner sense -- senses which, although combined in one subject, are extremely unlike each other. In outer sense we find no other outer effects save changes of place, and no forces except mere tendencies which issue in spatial relations as their effects. Within us, on the other hand, the effects are thoughts, among which is not to be found any relation of place, motion, shape, or other spatial determination, and we altogether lose the thread of the causes in the effects to which they are supposed to have given rise in inner sense. We ought, however, to bear in mind that bodies are not objects in themselves which are present to us, but a mere appearance of we know not what unknown object; that motion is not the effect of this unknown cause, but only the appearance of its influence on our senses. Neither bodies nor motions are anything outside us; both alike are mere representations in us; and it is not, therefore, the motion of matter that produces representations in us; the motion itself is representation only, as also is the matter which makes itself known in this way. Thus in the end the whole difficulty which we have made for ourselves comes to this, how and why the representations of our sensibility are so interconnected that those which we entitle outer intuitions can be represented according to empirical laws as objects outside us -- a question which is not in any way bound up with the supposed difficulty of explaining the origin of our representations from quite heterogeneous efficient causes outside us. That difficulty has arisen from our taking the appearances of an unknown cause as being the cause itself outside us, a view which can result in nothing but confusion. In the case of judgments in which a misapprehension has taken deep root through long custom, it is impossible at once to give to their correction that clarity P 357 which can be achieved in other cases where no such inevitable illusion confuses the concept. Our freeing of reason from sophistical theories can hardly, therefore, at this stage have the clearness which is necessary for its complete success. The following comments will, I think, be helpful as contributing towards this ultimate clarity. All objections can be divided into dogmatic, critical, and sceptical. A dogmatic objection is directed against a proposition, a critical objection against the proof of a proposition. The former requires an insight into the nature of the object such that we can maintain the opposite of what the proposition has alleged in regard to this object. It is therefore itself dogmatic, claiming acquaintance with the constitution of the object fuller than that of the counter-assertion. A critical objection, since it leaves the validity or invalidity of the proposition unchallenged, and assails only the proof, does not presuppose fuller acquaintance with the object or oblige us to claim superior knowledge of its nature; it shows only that the assertion is unsupported, not that it is wrong. A sceptical objection sets assertion and counter-assertion in mutual opposition to each other as having equal weight, treating each in turn as dogma and the other as the objection thereto. And the conflict, as the being thus seemingly dogmatic on both the opposing sides, is taken as showing that all judgment in regard to the object is completely null and void. Thus dogmatic and sceptical objections alike lay claim to such insight into their object as is required to assert or to deny something in regard to it. A critical objection, on the other hand, confines itself to pointing out that in the making of the assertion something has been presupposed that is void and merely fictitious; and it thus overthrows the theory by removing its alleged foundation without claiming to establish anything that bears directly upon the constitution of the object. So long as we hold to the ordinary concepts of our reason with regard to the communion in which our thinking subject stands with the things outside us, we are dogmatic, looking upon them as real objects existing independently of us, in accordance with a certain transcendental dualism which does not assign these outer appearances to the subject as representations, but sets them, just as they are given us in P 358 sensible intuition, as objects outside us, completely separating them from the thinking subject. This subreption is the basis of all theories in regard to the communion between soul and body. The objective reality thus assigned to appearances is never brought into question. On the contrary, it is taken for granted; the theorising is merely as to the mode in which it has to be explained and understood. There are three usual systems devised on these lines, and they are indeed the only possible systems: that of physical influence, that of predetermined harmony, and that of supernatural intervention. The two last methods of explaining the communion between the soul and matter are based on objections to the first view, which is that of common sense. It is argued, namely, that what appears as matter cannot by its immediate influence be the cause of representations, these being effects which are quite different in kind from matter. Now those who take this line cannot attach to what they understand by 'object of outer senses' the concept of a matter which is nothing but appearance, and so itself a mere representation produced by some sort of outer objects. For in that case they would be saying that the representations of outer objects (appearances) cannot be outer causes of the representations in our mind; and this would be a quite meaningless objection, since no one could dream of holding that what he has once come to recognise as mere representation, is an outer cause. On our principles they can establish their theory only by showing that that which is the true (transcendental) object of our outer senses cannot be the cause of those representations (appearances) which we comprehend under the title 'matter'. No one, however, can have the right to claim that he knows anything in regard to the transcendental cause of our representations of the outer senses; and their assertion is therefore entirely groundless. If, on the other hand, those who profess to improve upon the doctrine of physical influence keep to the ordinary outlook of transcendental dualism, and suppose matter, as such, to be a thing-in- itself (not the mere appearance of an unknown thing), they will direct their objection to showing that such an outer object, which in itself exhibits no causality save that of movements, can never be the efficient cause of representations, but that a P 359 third entity must intervene to establish, if not reciprocal interaction, at least correspondence and harmony between the two. But in arguing in this way, they begin their refutation by admitting into their dualism the proton pseudos of [a doctrine of] physical influence, and consequently their objection is not so much a disproof of natural influence as of their own dualistic presupposition. For the difficulties in regard to the connection of our thinking nature with matter have their origin, one and all, in the illicitly assumed dualistic view, that matter as such is not appearance, that is, a mere representation of the mind to which an unknown object corresponds, but is the object in itself as it exists outside us independently of all sensibility. As against the commonly accepted doctrine of physical influence, an objection of the dogmatic type is not, therefore, practicable. For if the opponent of the doctrine accepts the view that matter and its motion are mere appearances and so themselves mere representations, his difficulty is then simply this, that it is impossible that the unknown object of our sensibility should be the cause of the representations in us. He cannot, however, have the least justification for any such contention, since no one is in a position to decide what an unknown object may or may not be able to do. And this transcendental idealism, as we have just proved, he cannot but concede. His only way of escape would be frankly to hypostatise representations, and to set them outside himself as real things. The doctrine of physical influence, in its ordinary form, is, however, subject to a well-founded critical objection. The alleged communion between two kinds of substances, the thinking and the extended, rests on a crude dualism, and treats the extended substances, which are really nothing but mere representations of the thinking subject, as existing by themselves. This mistaken interpretation of physical influence can thus be effectively disposed of: we have shown that the proof of it is void and illicit. The much-discussed question of the communion between the thinking and the extended, if we leave aside all that is merely fictitious, comes then simply to this: how in a thinking subject outer intuition, namely, that of space, with its filling- in of shape and motion, is possible. And this is a question which no man can possibly answer. This gap in our knowledge P 360 can never be filled; all that can be done is to indicate it through the ascription of outer appearances to that transcendental object which is the cause of this species of representations, but of which we can have no knowledge whatsoever and of which we shall never acquire any concept. In all problems which may arise in the field of experience we treat these appearances as objects in themselves, without troubling ourselves about the primary ground of their possibility (as appearances). But to advance beyond these limits the concept of a transcendental object would be indispensably required. The settlement of all disputes or objections which concern the state of the thinking nature prior to this communion (prior to life), or after the cessation of such communion (in death), rests upon these considerations regarding the communion between thinking beings and extended beings. The opinion that the thinking subject has been capable of thought prior to any communion with bodies would now appear as an assertion that, prior to the beginning of the species of sensibility in virtue of which something appears to us in space, those transcendental objects, which in our present state appear as bodies, could have been intuited in an entirely different manner. The opinion that the soul after the cessation of all communion with the corporeal world could still continue to think, would be formulated as the view that, if that species of sensibility, in virtue of which transcendental objects, at present quite unknown to us, appear as a material world, should cease, all intuition of the transcendental objects would not for that reason be removed, and it would still be quite possible that those same unknown objects should continue to be known by the thinking subject, though no longer, indeed, in the quality of bodies. Now on speculative principles no one can give the least ground for any such assertion. Even the possibility of what is asserted cannot be established; it can only be assumed. But it is equally impossible for anyone to bring any valid dogmatic objection against it. For whoever he may be, he knows just as little of the absolute, inner cause of outer corporeal appearances as I or anybody else. Since he cannot, therefore, offer any justification for claiming to know on what the outer appearances in our present state (that of life) really rest, neither can he know that the condition of all outer intuition P 361 or the thinking subject itself, will cease with this state (in death). Thus all controversy in regard to the nature of the thinking being and its connection with the corporeal world is merely a result of filling the gap where knowledge is wholly lacking to us with paralogisms of reason, treating our thoughts as things and hypostatising them. Hence originates an imaginary science, imaginary both in the case of him who affirms and of him who denies, since all parties either suppose some knowledge of objects of which no human being has any concept, or treat their own representations as objects, and so revolve in a perpetual circle of ambiguities and contradictions. Nothing but the sobriety of a critique, at once strict and just, can free us from this dogmatic delusion, which through the lure of an imagined felicity keeps so many in bondage to theories and systems. Such a critique confines all our speculative claims rigidly to the field of possible experience; and it does this not by shallow scoffing at ever-repeated failures or pious sighs over the limits of our reason, but by an effective determining of these limits in accordance with established principles, inscribing its nihil ulterius on those Pillars of Hercules which nature herself has erected in order that the voyage of our reason may be extended no further than the continuous coastline of experience itself reaches -- a coast we cannot leave without venturing upon a shoreless ocean which, after alluring us with ever- deceptive prospects, compels us in the end to abandon as hopeless all this vexatious and tedious endeavour. * * * We still owe the reader a clear general exposition of the transcendental and yet natural illusion in the paralogisms of pure reason, and also a justification of the systematic ordering of them which runs parallel with the table of the categories. We could not have attempted to do so at the beginning of this section without running the risk of becoming obscure or of clumsily anticipating the course of our argument. We shall now try to fulfil this obligation. All illusion may be said to consist in treating the subjective condition of thinking as being knowledge of the object. Further in the Introduction to the Transcendental Dialectic we have P 362 shown that pure reason concerns itself solely with the totality of the synthesis of the conditions, for a given conditioned. Now since the dialectical illusion of pure reason cannot be an empirical illusion, such as occurs in certain specific instances of empirical knowledge, it will relate to what is universal in the conditions of thinking, and there will therefore be only three cases of the dialectical employment of pure reason. 1. The synthesis of the conditions of a thought in general. 2. The synthesis of the conditions of empirical thinking. 3. The synthesis of the conditions of pure thinking. In all these three cases pure reason occupies itself only with the absolute totality of this synthesis, that is, with that condition which is itself unconditioned. On this division is founded the threefold transcendental illusion which gives occasion for the three main sections of the Dialectic, and for the three pretended sciences of pure reason -- transcendental psychology, cosmology, and theology. Here we are concerned only with the first. Since, in thinking in general, we abstract from all relation of the thought to any object (whether of the senses or of the pure understanding), the synthesis of the conditions of a thought in general (No. 1) is not objective at all, but merely a synthesis of the thought with the subject, which is mistaken for a synthetic representation of an object. It follows from this that the dialectical inference to the condition of all thought in general, which is itself unconditioned, does not commit a material error (for it abstracts from all content or objects), but is defective in form alone, and must therefore be called a paralogism. Further, since the one condition which accompanies all thought is the 'I' in the universal proposition 'I think', reason has to deal with this condition in so far as it is itself unconditioned. It is only the formal condition, namely, the logical unity of every thought, in which I abstract from all objects; but nevertheless it is represented as an object which I think, namely, I myself and its unconditioned unity. If anyone propounds to me the question, 'What is the constitution P 363 of a thing which thinks? ', I have no a priori knowledge wherewith to reply. For the answer has to be synthetic -- an analytic answer will perhaps explain what is meant by thought, but beyond this cannot yield any knowledge of that upon which this thought depends for its possibility. For a synthetic solution, however, intuition is always required; and owing to the highly general character of the problem, intuition has been left entirely out of account. Similarly no one can answer in all its generality the question, 'What must a thing be, to be movable? ' For the question contains no trace of the answer, viz. impenetrable extension (matter). But although I have no general answer to the former question, it still seems as if I could reply in the special case of the proposition which expresses self-consciousness -- 'I think'. For this 'I' is the primary subject, that is, substance; it is simple, etc. But these would then have to be propositions derived from experience, and in the absence of a universal rule which expresses the conditions of the possibility of thought in general and a priori, they could not contain any such non-empirical predicates. Suspicion is thus thrown on the view, which at first seemed to me so plausible, that we can form judgments about the nature of a thinking being, and can do so from concepts alone. But the error in this way of thinking has not yet been detected. Further investigation into the origin of the attributes which I ascribe to myself as a thinking being in general can, however, show in what the error consists. These attributes are nothing but pure categories, by which I do not think a determinate object but only the unity of the representations -- in order to determine an object for them. In the absence of an underlying intuition the category cannot by itself yield a concept of an object; for by intuition alone is the object given, which thereupon is thought in accordance with the category. If I am to declare a thing to be a substance in the [field of] appearance, predicates of its intuition must first be given me, and I must be able to distinguish in these the permanent from the transitory and the substratum (the thing itself) from what is merely inherent in it. If I call a thing in the [field of] appearance simple, I mean by this that the intuition of it, although a part of the appearance, is not P 364 itself capable of being divided into parts, etc. But if I know something as simple in concept only and not in the [field of] appearance, I have really no knowledge whatsoever of the object, but only of the concept which I make for myself of a something in general that does not allow of being intuited. I say that I think something as completely simple, only because I have really nothing more to say of it than merely that it is something. Now the bare apperception, 'I', is in concept substance, in concept simple, etc. ; and in this sense all those psychological doctrines are unquestionably true. Yet this does not give us that knowledge of the soul for which we are seeking. For since none of these predicates are valid of intuition, they cannot have any consequences which are applicable to objects of experience, and are therefore entirely void. The concept of substance does not teach me that the soul endures by itself, nor that it is a part of outer intuitions which cannot itself be divided into parts, and cannot therefore arise or perish by any natural alterations. These are properties which would make the soul known to me in the context of experience and might reveal something concerning its origin and future state. But if I say, in terms of the mere category, 'The soul is a simple substance', it is obvious that since the bare concept of substance (supplied by the understanding) contains nothing beyond the requirement that a thing be represented as being subject in itself, and not in turn predicate of anything else, nothing follows from this as regards the permanence of the 'I', and the attribute 'simple' certainly does not aid in adding this permanence. Thus, from this source, we learn nothing whatsoever as to what may happen to the soul in the changes of the natural world. If we could be assured that the soul is a simple part of matter, we could use this knowledge, with the further assistance of what experience teaches in this regard, to deduce the permanence, and, as involved in its simple nature, the indestructibility of the soul. But of all this, the concept of the 'I', in the psychological principle 'I think', tells us nothing. That the being which thinks in us is under the impression that it knows itself through pure categories, and precisely P 365 through those categories which in each type of category express absolute unity, is due to the following reason. Apperception is itself the ground of the possibility of the categories, which on their part represent nothing but the synthesis of the manifold of intuition, in so far as the manifold has unity in apperception. Self-consciousness in general is therefore the representation of that which is the condition of all unity, and itself is unconditioned. We can thus say of the thinking 'I' (the soul) which regards itself as substance, as simple, as numerically identical at all times, and as the correlate of all existence, from which all other existence must be inferred, that it does not know itself through the categories, but knows the categories, and through them all objects, in the absolute unity of apperception, and so through itself. Now it is, indeed, very evident that I cannot know as an object that which I must presuppose in order to know any object, and that the determining self (the thought) is distinguished from the self that is to be determined (the thinking subject) in the same way as knowledge is distinguished from its object. Nevertheless there is nothing more natural and more misleading than the illusion which leads us to regard the unity in the synthesis of thoughts as a perceived unity in the subject of these thoughts. We might call it the subreption of the hypostatised consciousness (apperceptionis substantiatae). If we desire to give a logical title to the paralogism contained in the dialectical syllogisms of the rational doctrine of the soul, then in view of the fact that their premisses are correct, we may call it a sophisma figurae dictionis. Whereas the major premiss, in dealing with the condition, makes a merely transcendental use of the category, the minor premiss and the conclusion, in dealing with the soul which has been subsumed under this condition, use the same category empirically. Thus, for instance, in the paralogism of substantiality, the concept of substance is a pure intellectual concept, which in the absence of the conditions of sensible intuition admits only of transcendental use, that is, admits of no use whatsoever. But in the minor premiss the very same concept is applied to the object P 366 of all inner experience without our having first ascertained and established the condition of such employment in concreto, namely, the permanence of this object. We are thus making an empirical, but in this case inadmissible, employment of the category. Finally, in order to show the systematic interconnection of all these dialectical assertions of a pseudo-rational doctrine of the soul in an order determined by pure reason, and so to show that we have them in their completeness, we may note that apperception has been carried through all the classes of the categories but only in reference to those concepts of understanding which in each class form the basis of the unity of the others in a possible perception, namely, subsistence, reality, unity (not plurality), and existence. Reason here represents all of these as conditions, which are themselves unconditioned, of the possibility of a thinking being. Thus the soul knows in itself -- (1) the unconditioned unity of relation, i.e. that it itself is not inherent [in something else] but self-subsistent. (2) the unconditioned unity of quality, that is, that it is not a real whole but simple. (3) the unconditioned unity in the plurality in time, i.e. that it is not numerically different at different times but one and the very same subject. (4) the unconditioned unity of existence in space, i.e. that it is not the consciousness of many things outside it, but the consciousness of the existence of itself only, and of other things merely as its representations. Reason is the faculty of principles. The assertions of pure psychology do not contain empirical predicates of the soul but those predicates, if there be any such, which are meant to determine the object in itself independently of experience, and so by mere reason. They ought, therefore, to be founded on principles and universal concepts bearing on the nature of thinking beings in ge neral. ++ How the simple here again corresponds to the category of reality I am not yet in a position to explain. This will be shown in the next chapter on the occasion of this same concept being put by reason to yet another use. P 367 But instead we find that the single representation, 'I am', governs them all. This representation just because it expresses the pure formula of all my experience in general announces itself as a universal proposition valid for all thinking beings; and since it is at the same time in all respects unitary, it carries with it the illusion of an absolute unity of the conditions of thought in general, and so extends itself further than possible experience can reach.