sciences are themselves at present able to attain. It is quite enough that we should be able so to conceive of philosophy, in a tentative and hypothetical way, that it shall seem more available and therefore valuable in respect to the practical mission which it aims to fulfill.
There can be little doubt that many of the previous claims made during the history of the development of reflective thinking among mankind, have, by their exaggeration and their failure to make themselves good in experience, contributed to the prevalent disparaging judgment of both the theoretical tenability and the practical value of philosophy. For example, in the preface to the Principles of Philosophy, Descartes contends that, by the wisdom which philosophy imparts, we are to understand "not merely prudence in the management of affairs, but a perfect knowledge of all that man can know, as well for the conduct of his life as for the preservation of his health and the discovery of all the arts. And that knowledge, to subserve these ends, must necessarily be deduced from first principles."
But during the century which has elapsed since the death of the great master of the critical and a priori philosophy, the result of his failures has been more conspicuous than that of his successes. This has naturally caused men to withdraw their confidence from all attempts "to deduce from first principles" a "perfect knowledge of all that man can know," in a form to subserve all the practical ends of life and "the discovery of all the arts." And to-day the most extensive claims of the most haughty advocate of the supremacy of the 'science of sciences' would scarcely venture in the face of modern opinion to make good the conception of Descartes.
It was the attempt by the deductive method to gain a perfect knowledge of the transcendent world which Kant controverted, and which he supposed himself to have once for all thrown out of court for those who should be able to see clearly what were the constitutional limits of human reason in its speculative use. In the form which metaphysics had then taken as a development in somewhat direct line from the Cartesian principles, it is not perhaps untrue to the facts of history to say that Kant accom-
