THE DISTINCTION OF INNER AND OUTER EXPERIENCE. 63 was clearly brought out by Kant. It lay beyond Kant's mental horizon to discuss the distinction of outer and inner from the point of view of the historical growth of experience. But he accepts the distinction as justifiable and incorporates it in his theory of knowledge. That which is in space and time belongs to outer sense, that which is in time alone belongs to inner sense. And there is a necessary connexion between the two spheres, for that which is determined in space is determined from the side of the subject in terms of inner sense. By attending to the mental process by which all objects become possible the inward side of experience would be differentiated from the outer. But Kant afterwards saw that in putting this interpretation on the common dis- tinction he involved himself in difficulties which affected the consistency of his theoretical philosophy. For the inner life was perpetually changing, and we could not, as he thought, apply to it the category of substance as the permanent in time. Nor could that product of Kantian abstraction, the spectral pure ego which was without content, serve as a permanent unity to which inner changes were referred. Accordingly in the second edition of the Critique, in the "Remark on the Principles of Judgment," we find Kant modifying his earlier view, and asserting that outer sense is presupposed in the conscious determination of ourselves in time. "It is by means of external perception that we make intelligible to ourselves the various successive changes in which we ourselves exist. . . . No change can possibly be an object of experience apart from the consciousness of something that is permanent, and in inner sense nothing that is permanent can be found." On this view it would be as logically subsequent to and contrasted with the deter- mination of objects in space that the consciousness of inner experience is possible. 1 It is of course evident that Kant in 1 Dr. Caird thinks that the modifications in statement made by Kant in dealing with this point in the second edition of his Critique indicate a movement of his mind, of which perhaps he was not himself fully conscious, towards a larger and more consistent idealism (Phil, of Kant, i., 417, 614). I am not aware how far he is supported in this view by competent Kan- tian scholars. But I venture to think that Kant simply desired to give a statement of his critical idealism less open to objection and more care- fully guarded than that which he had given in the first edition and hi the Prolegomena. While he shows in the second edition that inner sense depends on outer sense, he also repeats that a phenomenon (Erschein- urig) must be a phenomenon of Something (ed. Kehrbach, p. 23). And though he admits that this reference of perception to a reality beyond it might not be necessary for intellectual perception (op. cit. p. 32), yet it is no part of his theory that human intelligence is implicitly a conscious- ness which is capable of exercising an intellectuelle Anschauung.
