74 AETHUB JAMES BALFOUE. described by Kant himself as his disciples, and that the most Hegelian would, I suppose, accept very little without quali- fication of Hegel's positive contributions to the theory of the universe. Still, much as they differ among themselves, their mode of attacking the problems of philosophy is sufficiently similar to make it just, as it is undoubtedly con- venient, to give them a common name ; and no name is perhaps more appropriate than that of Neo-Kantian, which indicates both their connexion with and their difference from the philosopher to whom they most often appeal. By this school many valuable contributions to meta- physical literature have been made during recent years. But they have, I believe, been all, or almost all, of one kind. They have been devoted exclusively to criticising or expounding the views of previous thinkers ; never, until these Prolegomena appeared, to systematising the opinions of any members of the school themselves. These opinions had to be collected from such works as Green's Introduction to Hume, or Professor Caird's treatise on Kant ; works from which, naturally enough, information respecting the philo- sophy of Hume and Kant could be more easily extracted, than information respecting the philosophy of Green and Caird. The singular uniformity with which this rule has been observed causes especial interest to attach to the first im- portant violation of it ; and the interest is greatly strengthened by the fact that Green, to whom this fortunate innovation is due, is the individual who, perhaps more than any other, has contributed by his writings and by his personal influence to the spread of the new ideas. We can now for the first time contemplate in a connected whole the outlines of the Neo- Kantian scheme of metaphysics ; and it is surely of the greatest importance to the interests of Philosophy that a serious effort should be made by those who are not as yet prepared to accept the scheme as it stands, to explain where their difficulties lie. The following pages are intended as a contribution to this object. They aim neither at estimating the genius of the author of the Prolegomena, nor at investi- gating the sources from which his system may be in part derived. I have throughout treated the " Metaphysics of Knowledge " critically not historically as a body of reasoned doctrines, logically self-sufficient and self-contained, the value of which has to be tested by argument and by argument alone. I am aware that the result of this may be to give a controversial tone to the succeeding comments which in the opinion of many may seem unnecessary and even, under the circumstances, misplaced. But, after all, it is only by con-
