408 NEW BOOKS. theoretical side of the work presented by Dr. Sidis and his colleagues, since the full statement of their principles is postponed. Apparently the theory of subconscious mental systems is accepted without reserve ; in its applications to the cases presented it bears a close resemblance to Janet's theory of desa<i/'i'</<tfi<>n mentale. Since, however, almost the only mention of former investigations consists in references to previous work of Dr. Sidis, it is rather difficult to understand in what relation the work is supposed to stand to that of other investigators. In general the volume presents a vigorous and interesting attempt to analyse the phenomena of mental disease. The details in the application of the methods show great patience and ingenuity, and even where the general conclusions which are offered seem not to have an adequate basis of fact the mode of interpretation and presentation is suggestive. W. G. SMITH. The Economic Jt/t^r/nrtntin,, <>/ Ui^tnnj. By EDWIN R. A. SELIGMAN. New York : The Columbia University Press ; London : Macmillan & Co., 1902. Pp. ix., 166. This is in the main a reproduction of some articles that appeared in the I'olificitl Nr/Vmr (>inn 1<-rhj. The gist of Prof. Seligman's contention is contained in the following passage (pp. 157-8): "Human activity is indeed the activity of sentient beings, and, therefore, the history of mankind is the history of mental development ; but human life depends upon the relation between the individual and his environment. In the struggle that has thus far gone on between individuals and groups in their desire to make the best of their environment, the paramount con- siderations have necessarily been economic in character. The view of history which lays stress on these paramount considerations is what we call the economic interpretation of history. They are not the exclusive considerations, and in particular instances the action and reaction of social forces may give the decisive influence to non -economic factors. Taking man, however, for what he has thus far been and still is, it is difficult to deny that the underlying influence in its broadest aspects has very generally been of this economic character. The economic interpretation of history, in its proper formulation, does not exhaust the possibilities of life and progress ; it does not explain all the niceties of human development ; but it emphasises the forces which have hitherto been so largely instrumental in the rise and fall, in the prosperity and decadence, in the glory and failure, in the weal and woe of nations and peoples. It is a relative, rather than an absolute, explanation. It is substantially true of the past ; it will tend to become less and less true of the future." In developing his theme, the author displays considerable learning and not a little critical acumen. His judgments are sober and carefully formed ; but of course his treatment cannot pretend to be exhaustive. Apart from a somewhat detailed consideration of the great movements of history, general statements on such a subject, when not paradoxical, are apt to be almost truistic. Mr. Seligman has, however, given us a vigorous sketch of an important subject ; and we may perhaps hope for a more thorough investigation of it in future. J. S. M.
