DISCUSSIONS.
PROFESSOR LADD'S CRITICISM OF JAMES'S PSYCHOLOGY.
There seem to me to be two features in James's Psychology of epoch-making importance: (1) its point of view, its conception of psychology as a natural science; (2) its contention that all our so-called ideas at any moment form one undivided mental state.
Professor Ladd (Review, No. 1) confines himself almost entirely to the first of these. He criticises it on the following grounds: (1) that psychology as a natural science is not a science; (2) that it can never become one; (3) that as Professor James conceives it, it excludes nearly all the scientific data and conclusions of psychology, — among them, nearly all those of physiological psychology, and all of introspection psychology as explanatory science; (4) that Professor James himself does not treat psychology as a natural science, that the "metaphysics of physics is interwoven into the very texture of both his volumes," thereby illustrating the fact that his conception is impracticable and erroneous.
Of the first argument it is sufficient to say that it is not to the point as criticism of a book that is described by its author as "mainly a mass of descriptive details."
But psychology is not only not a natural science now, it can never become one. "The attempt to establish psychology as a natural science upon such an extremely tenuous and cloudy foundation as our present or prospective knowledge of cerebral 'explosions' and 'overlappings' is doomed to failure from the very beginning." How does Professor Ladd know? How has he been able to measure the possibilities of the human mind? And, supposing he is right, has the limit of human achievement in this direction been already reached? If not, it would seem worth while for investigators to prosecute their inquiries in this field a little longer. Moreover, if Professor Ladd is right, the best way to prove it is to treat psychology as a natural science precisely in the sense in which Professor James conceives it. The first condition not only of solving a problem, but of proving that it is insoluble is to clearly conceive it. As Professor James puts it in his shorter work, "To work an hypothesis for all it is worth is the real and often the only way to prove its insufficiency." From Professor Ladd's own point of view, therefore, just such a clear and definite formulation of the problem of psychology as Professor James makes seems to me to have a very high value.
