Page:Mind (New Series) Volume 8.djvu/271

 HANS CORNELIUS, Psychologie als Erfahrungswissenschaft. 257 knowledge both of mind and matter. Its application to mind is the more interesting, but the English reader will be better enabled to catch the drift of the author if we first refer to his account of our belief in the external world. In his fifth chapter, which treats of this topic, he makes no reference to Mill's famous discus- sion in the Examination of Hamilton, and he does not use the phrase " permanent possibility of sensations ". Yet his theory is simply identical with Mill's. Concepts of material objects as existing independently of the subject which cognises them are for him, as for Mill, simply concepts of the possibility of obtaining certain sensations by the observance of certain conditions. He calls them " concepts of empirical connexion". A material object is for him simply an organised group of expectations. He does not deal with the objections which have been brought against this theory; indeed, he seems to be unaware of them. For instance, he does not face the difficulty that the order and con- nexion of physical facts is quite different from any possible order and connexion of subjective experiences in the way of sensation, e.g., that though we cannot see or touch simultaneously the inside and the outside of a solid body, yet both exist simultane- ously. Nor does he explain how it is that physical science recog- nises the existence of much which cannot by its very nature be actually experienced in the way of sensation, e.g., molecules and their interaction, the luminiferous ether, and so on. It is charac- teristic of Cornelius's point of view that he refuses to assume the existence of the material world as a datum for explaining the process by which the individual mind comes to be aware of such a world. For him this would be arguing in a circle. He supposes that the only means of ascertaining the nature and validity of our knowledge of the external world is by tracing its psychological growth. If we assume such a world to be given at the outset, we already prejudge the question which is to be solved. In following this line of thought, Prof. Cornelius appears to us to place himself in an altogether untenable position. He confuses two distinct problems ; on the one hand, there is the question, How does the apprehension of an external world, such as it actually exists for ordinary consciousness, come into being ? on the other, there is the question, whether the view taken of the external world by the ordinary consciousness is a right one ; and what sort of correction it requires from critical reflexion. If these two problems are identified, confusion may arise in two ways. Either pyschology is substituted for epistemology, or epistemology for psychology. In the first case, an account of the stages through which the ordinary consciousness of the external world has arisen, takes the place of a criticism of its validity. In the second case, an account is given, not of the processes by which the ordinary consciousness of the external world arises, but of the processes by which an author supposes that what he takes to be the true view of external reality may be obtained. It is the second course which is followed 17