The influence of Locke and Hume upon the form of Mr. Ruskin’s theories is obvious and avowed. He believes that ‘fact,’ ‘nature,’ and ‘truth’ are only given in sense-perception, and that therefore sensation gives us the truest and fullest knowledge of reality; his distrust of ideas is due to the belief that they distort and obscure the revelations of this unerring mirror of reality. But these assumptions do justice neither to the real independence of the physical world, nor to the claims of the mind to discover and possess absolutely reliable knowledge. And when we are dealing with such a concrete reality as pictorial art we cannot afford to do less than the fullest justice to both nature and mind. We cannot, like the practical man or the students of the physical sciences, rule out the unseen world of human feeling as irrelevant to our immediate purposes, any more than we can neglect the concrete course of phenomena, like the student of the _a priori_ forms of knowledge. In art we have to do with nature and mind in active co-operation. We are therefore bound to treat them as two factors in a common process. We cannot have two aims in art, and we cannot separate (_a_) physical objects from (_b_) an artist’s thoughts and feelings; if we make the attempt we are inevitably driven, as we have seen Mr. Ruskin driven, to maintain that (_a_) is (_b_), and (_b_) (_a_), and then the point of our distinction seems lost. In art criticism the problem is not to separate mind from nature, but to unite them--to bring out the permanent and universal relation which binds them together. And the only way to do this is to treat them both as elements or members in the formed world of the self-conscious subject. It is not the special business of art criticism to show that the conception of nature as what is ‘given’ in sense-perception, and as ‘God’s work’ as distinguished from the action of human intelligence, is contradictory and untenable. The work is already done. The theory of the perceptive judgment, upon which all modern philosophies, realist as well as idealist, are based, is too firmly established to render necessary any further discussion of Locke’s and Hume’s imperfect analysis of perception. All that art criticism has to do is to realise that its own point of view is essentially identical with the point of view of logic and metaphysic, and to adopt and use any of the established truths of these sciences which are relevant to its purposes.