C. STU3IPF'S TONPSYCHOLOGIE, I. 599 and the special the case that, in reading the introductory part, one is apt to be irritated by the frequent forward references and hints of what is coining. In addition to these difficulties in getting at the author's theory as a whole, there are others arising from the want of any clear simple arrangement. There seems to be a haphazardness in the sequence of topics. This would probably have been removed by the addition of a synthetic to a purely analytic treatment, a progressive unfolding of a doctrine of sensa- tion in its relation to stimulus, of attention and its effects, and finally of sense-judgment and its several forms. The above brief account of the author's theory will suffice to indicate its great psychological importance just now. Dr. Stumpf is thoroughly abreast with the latest results of psycho-physical research. And he has given a new turn to the discussion of the problems involved, by emphasising the psychical complexity of phenomena which the mere physiologist is apt to regard as quite simple. The whole conception of sense-judgment, though of course not altogether new, is a real contribution to a sound psychology of the senses. Further, his attempts to distinguish the different factors in the formation of sense-judgments and to apply the methods of Fechner and others to the determination of their value must be welcomed by all those who desire to see psychology transformed into what Kant said it never could be, an exact science. At the same time it strikes me that, in maintaining the exist- ence and importance of the internal intellectual element in sense-perception over against mere sensation, the author has fallen into a kind of psychological dualism. Sensations are conceived as real things having a perfectly definite content independently of the mind which may or may not observe them. Dr. Stumpf makes a show of contending that the sensations, the existence of which he thus asserts, are not " unconscious," but this can hardly be taken seriously. An impression which I cannot detect with a full act of attention cannot surely have any individual existence in my consciousness, however wide we make the region of consciousness. The author adopts a not infrequent tone of irony when dealing with the objections of Delbceuf to such a conception, but he seems to forget that Fechner, towards whom he is of course always most respectful, is quite as clear as Del- bceuf on this point. Is not Fechner's conception of a tendency to a psychical result, due to the presence of certain of the co- operant conditions, much more scientific than that of an actual result of which we can know nothing, even if the very conception of it is not self-contradictory ? Surely in psychology it is time to recognise that in employing popular language and talking about sensations and attention to sensations we are speaking loosely. A sensation is a product of external and internal con- ditions combined. Its particular content is of course determined, largely at least, by the former, but this content is only realised