114 NEW BOOKS. which appeared in 1783, two years after the first edition of the Critique. Of the peculiarity, not to say the weakness, so essential to Kantism, of this dualism of pure and practical reason, the thorough-paced intei- lectualist Aristotle keeps clear. But for ' practical reason ' we should have had from Kant no metaphysics, neither speculative nor practical. Kantian metaphysics deal with the Absolute, with the unknowable, but not with the unthinkable, nor with the unbelievable, nay, they deal with that which man must think and believe, in virtue of those ' ideas of superior reason,' self, world, God, and again those ' postulates of practical reason,' God, liberty, immortality (pp. 198-199). Not only are we compelled to think as though these things were, but further we are driven und>er stress of the ' categorical imperative,' to admit them for certainties certainties, however, of a peculiar order, not truths intellectually discerned and evidenced, but practical needs of our nature (pp. 207-208). In this re- admission of metaphysics by a side-door after they have been ejected by the main entrance, Comte and Kant act consistently together, as M. Sentroul points out in an interesting page (p. 190). Kant will ever have his admirers ; it is for them to defend him against the witticism of Secre"tan (quoted on p. 192) : " There are two parts in the system of Kant, a science which is not true, and a truth which is not known ". Any student seeking an introduction to Kant would do well to apply to M. Sentroul. A book so pregnant with thought should have an index. J. RICKABY. Die Bilder von der Materie. Eine psychologische Untersuchung iiber die Grundlagen der Physik. By Dr. JULIUS SCHULTZ. Gottingen : Van- denhoeck & Euprecht. London : Williams and Norgate, 1905. Pp. viii, 201. It is a somewhat curious fact that though no country has been more productive "than Germany of starting-points for that pragmatist move- ment which is now manifesting itself so vigorously in American, English, French and Italian philosophy, yet it has nowhere been more difficult hitherto to find a contemporary thinker who employs the new mode of philosophising in its entirety. In very various ways Lotze, Wundt, Ostwald, Mach, Nietzsche, Paulsen, Windelband, Eucken, Sinimel and Jerusalem have all made important and even essential contributions to the new standpoint ; but somehow no one has seemed able to put them together and to perceive their full significance. Germany in short has lagged behind ; in part, perhaps, because she has been strangely remiss in translating James's epoch-making Psychology. In Dr. Schultz, however, we may welcome an almost full-blown, and certainly full-blooded, pragmatist, whose testimony is not the less precious because he seems to have developed his position for himself. He had shown in his remarkable Psychologie der Axiome how clearly he had perceived that our axiomatic principles are human postulates whose meaning lies in their relation to experience. Or as he well says in his present work, which is as lively and stimulating as its predecessor, though its ingenious discussions are so technical as to appeal primarily to physi- cists, an axiom is "a proposition curiously coagulated out of a priori postulation, arbitrary construction and empirical testing" (p. 39). He has grasped, that is, how very complex these ' self-evident ' principles really are. But still there is a striking divergence from the type of prag- matism with which we are familiar in this country. Dr. Schultz considers his method apriorist, and himself a Kantian, and an opponent of positivism in science. This clearly shows that empiricism for him is still the enemy,,
