is, not to find a mysterious higher reality beyond experience, but to unify the latter, to render it self-consistent.
It is impossible to summarize in a few words Ostwald's very condensed sketch of his Naturphilosophie. There are some interesting and true things said in regard to laws of nature, order, space, time, the place of mathematics in science, etc., etc.; but, on the whole, the essay is an exhibition of the futility of undertaking to set up a reasoned world-view without an adequate comprehension of the development of modern philosophy. When, for instance, Ostwald discusses the empirical origin of mathematics he misses entirely the meaning of Kant's inquiry in regard to the foundations of knowledge, and, when he develops his theory of energy as the unifying and all-explaining category for life, mind, self-consciousness, society, morals, etc., we are treated to the sad spectacle of an eminent chemist entering fields of whose peculiar character and significance for philosophy he has hardly an inkling. We are offered a barren abstraction, an x called 'energy,' a "night in which all cows are black." We are asked to believe that there is a philosophical import in calling society, morality, art, religion, and knowledge, and the minds that create these realities, forms of energy. If anyone regards this process of kalsomining the world of differentiated experience into dull monochrome as up-to-date philosophizing, for him, of course, Kant and Hegel, Plato and Aristotle, have lived in vain.
Ebbinghaus gives a comprehensive, and, in the main, sound outline of psychology. His treatment of the problem of mind and body is, however, open to criticism. If he offers the parallelistic theory simply as a methodological assumption for psychological inquiry, he should have said as much; if it is offered as a final or metaphysical theory, then alternative views are treated too cavalierly, and his arguments for parallelism are not adequate. One does not establish the final truth of parallelism simply by an appeal to the law of the conservation of energy and by a citation of the experiments of Rubner and At- water on outgo and intake of animal energy.
In the essay Philosophie der Geschichte Eucken shows, first, the necessity of a philosophy of history, from the need that civilized man, with his historical culture, is under of settling his accounts with the past and determining in what relation the present should stand to the past. Eucken points out that the notions of the significance of history, of progress, etc., are of Christian origin. He traces the growth in modern times of the historical consciousness and of an explicit philosophy of history. After pointing out the weakness of the economic and positi-
