Page:Mind (New Series) Volume 8.djvu/272

 258 CRITICAL NOTICES: by Cornelius. His doctrine of the nature of external reality is determined from the outset by his general theory of knowledge ; and the psychological part of his work simply consists in showing how an individual mind may attain, not the actually existing appre- hension of an external world, with all its possible errors and confusions, but that view of it which, according to Cornelius, is the true one. The result is that his psychology, so far as regards this question, is merely his theory of knowledge in masquerade. We have still to consider the alleged circle of assuming the existence of an external world when the problem is to trace its origin. In reality, there is no such circle, so long as we retain the strictly psychological attitude. The psychologist has to investigate the processes through which the presentation of an external world grows up in an individual subject. It would certainly be a circle to assume that this subject whom he is studying already possesses a knowledge of the external world, but it is no circle to assume that he himself possesses such a knowledge. If he did not possess such a knowledge, the problem could have no existence for Mm. The most interesting application which Cornelius makes of his theory of knowledge is to the nature of psychological analysis. We may merely by attention, without alteration of other con- ditions, succeed in discriminating in a presented object constituents which we have previously failed to discriminate. On the other hand, so soon as attention is withdrawn, the distinctions which previously existed disappear. In a musical note, for example, we only discriminate overtones when we specially attend to them. The problem discussed by Cornelius is as follows : What sort of existence, if any, have the discriminated differences before they are discerned and after they have ceased to be discerned ? In both cases he answers in accordance with his general theory of knowledge that undiscriminated differences exist only as per- manent possibilities of discrimination. If I say that in a complex of sensible qualities elements exist which I do not distinguish, I merely mean, or at least ought merely to mean, that these elements would be discernible by me under certain conditions. This view certainly evades many difficulties, and it has a neatness which is attractive. For reasons which I have given elsewhere, I cannot myself accept it. It has been criticised most thoroughly by Mr. Shand in his article on " Feeling and Thought " (MiND, N.S., No. 28, October, 1898). The apparent simplicity of Prof. Cornelius's theory of psycho- logical analysis is marred by a further development which the facts compel him to give to it. When differences cease to be discriminated, they ought, according to the theory, to exist only as possibilities of discrimination. It is therefore with something of a shock that we find Cornelius treating them as persistent agencies determining the whole course of mental life. The total