Now to these conceptions relate four paralogisms of a transcendental psychology, which is falsely held to be a science of pure reason, touching the nature of our thinking being. We can, however, lay at the foundation of this science nothing but the simple and in itself perfectly contentless representation “i” which cannot even be called a conception, but merely a consciousness which accompanies all conceptions. By this “I,” or “He,” or “It,” who or which thinks, nothing more is represented than a transcendental subject of thought = x, which is cognized only by means of the thoughts that are its predicates, and of which, apart from these, we cannot form the least conception. Hence in a perpetual circle, inasmuch as we must always employ it, in order to frame any judgement respecting it. And this inconvenience we find it impossible to rid ourselves of, because consciousness in itself is not so much a representation distinguishing a particular object, as a form of representation in general, in so far as it may be termed cognition; for in and by cognition alone do I think anything.
It must, however, appear extraordinary at first sight that the condition under which I think, and which is consequently a property of my subject, should be held to be likewise valid for every existence which thinks, and that we can presume to base upon a seemingly empirical proposition a judgement which is apodeictic and universal, to wit, that everything which thinks is constituted as the voice of my consciousness declares it to be, that is, as a self-conscious being. The cause of this belief is to be found in the fact that we necessarily attribute to things à priori all the properties which constitute conditions under which alone we can cogitate them. Now I cannot obtain the least representation of a thinking being by means of external experience, but solely through self-consciousness. Such objects are consequently nothing more than the transference of this consciousness of mine to other things which can only thus be represented as thinking beings. The proposition, “I think,” is, in the present case, understood in a problematical sense, not in so far as it contains a perception of an existence (like the Cartesian “Cogito, ergo sum”), but in regard to its mere possibility—for the purpose of discovering what properties may be inferred from so simple a proposition and predicated of the subject of it.
If at the foundation of our pure rational cognition of thinking beings there lay more than the mere Cogito—if we could likewise call in aid observations on the play of our thoughts, and the thence derived natural laws of the thinking self, there would arise an empirical psychology which would be a kind of physiology of the internal sense and might possibly be capable of explaining the phenomena of that sense. But it could never be available for discovering those properties which do not belong to possible experience (such as the quality of simplicity), nor could it make any apodeictic enunciation on the nature of thinking beings: it would therefore not be a rational psychology.
Now, as the proposition “I think” (in the problematical sense) contains the form of every judgement in general and is the constant accompaniment of all the categories, it is manifest that conclusions are drawn from it only by a transcendental employment of the understanding. This use of the understanding excludes all empirical elements; and we cannot, as has been shown above, have any favourable conception beforehand of its procedure. We shall therefore follow with a critical eye this proposition through all the predicaments of pure psychology; but we shall, for brevity’s sake, allow this examination to proceed in an uninterrupted connection.
Before entering on this task, however, the following general remark may help to quicken our attention to this mode of argument. It is not merely through my thinking that I cognize an object, but only through my determining a given intuition in relation to the unity of consciousness in which all thinking consists. It follows that I cognize myself, not through my being conscious of myself as thinking, but only when I am conscious of the intuition of myself as determined in relation to the function of thought. All the modi of self-consciousness in thought are hence not conceptions of objects (conceptions of the understanding—categories); they are mere logical functions, which do not present to thought an object to be cognized, and cannot therefore present my Self as an object. Not the consciousness of the determining, but only that of the determinable self, that is, of my internal intuition (in so far as the manifold contained in it can be connected conformably with the general condition of the unity of apperception in thought), is the object.
1. In all judgements I am the determining subject of that relation which constitutes a judgement. But that the I which thinks, must be considered as in thought always a subject, and as a thing which cannot be a predicate to thought, is an apodeictic and identical proposition. But this proposition does not signify that I, as an object, am, for myself, a self-subsistent being or substance. This latter statement—an ambitious one—requires to be supported by data which are not to be discovered in thought; and are perhaps (in so far as I consider the thinking self merely as such) not to be discovered in the thinking self at all.
2. That the I or Ego of apperception, and consequently in all thought, is singular or simple, and cannot be resolved into a plurality of subjects, and therefore indicates a logically simple subject—this is self-evident from the very conception of an Ego, and is consequently an analytical proposition. But this is not tantamount to declaring that the thinking Ego is a simple substance—for this would be a synthetical proposition. The conception of substance always relates to intuitions, which with me cannot be other than sensuous, and which consequently lie completely out of the sphere of the understanding and its thought: but to this sphere belongs the affirmation that the Ego is simple in thought. It would indeed be surprising, if the conception of “substance,” which in other cases requires so much labour to distinguish from the other elements presented by intuition—so much trouble, too, to discover whether it can be simple (as in the case of the parts of matter)—should be presented immediately to me, as if by revelation, in the poorest mental representation of all.
3. The proposition of the identity of my Self amidst all the manifold representations of which I am conscious, is likewise a proposition lying in the conceptions themselves, and is consequently analytical. But this identity of the subject, of which I am conscious in all its representations, does not relate to or concern the intuition of the subject, by which it is given as an object. This proposition cannot therefore enounce the identity of the person, by which is understood the consciousness of the identity of its own substance as a thinking being in all change and variation of circumstances. To prove this, we should require not a mere analysis of the proposition, but synthetical judgements based upon a given intuition.
4. I distinguish my own existence, as that of a thinking being, from that of other things external to me—among which my body also is reckoned. This is also an analytical proposition, for other things are exactly those which I think as different or distinguished from myself. But whether this consciousness of myself is possible without things external to me; and whether therefore I can exist merely as a thinking being (without being man)—cannot be known or inferred from this proposition.
Thus we have gained nothing as regards the cognition of myself as object, by the analysis of the consciousness of my Self in thought. The logical exposition of thought in general is mistaken for a metaphysical determination of the object.
Our Critique would be an investigation utterly superfluous, if there existed a possibility of proving à priori, that all thinking beings are in themselves simple substances, as such, therefore, possess the inseparable attribute of personality, and are conscious of their existence apart from and unconnected with matter. For we should thus have taken a step beyond the world of sense, and have penetrated into the sphere of noumena; and in this case the right could not be denied us of extending our knowledge in this sphere, of establishing ourselves, and, under a favouring star, appropriating to ourselves possessions in it. For the proposition: “Every thinking being, as such, is simple substance,” is an à priori synthetical proposition; because in the first place it goes beyond the conception which is the subject of it, and adds to the mere notion of a thinking being the mode of its existence, and in the second place annexes a predicate (that of simplicity) to the latter conception—a predicate which it could not have discovered in the sphere of experience. It would follow that à priori
