No such treatise, however, is it our object to compose. We have said enough to show the true nature of that theory of association, as a branch of which alone is it possible to take any intelligible view of Mr Ruskin's _Theoria_, or "Theoretic Faculty." His flagrant error is, that he will represent a part for the whole, and will distort and confuse everything for the sake of this representation. Viewed in their proper limitation, his remarks are often such as every wise and good man will approve of. Here and there too, there are shrewd intimations which the psychological student may profit by. He has pointed out several instances where the associations insisted upon by writers of the school of Alison have nothing whatever to do with the sentiment of beauty; and neither harmonise with, nor exalt it. Not all that may, in any way, _interest_ us in an object, adds to its beauty. "Thus," as Mr Ruskin we think very justly says, "where we are told that the leaves of a plant are occupied in decomposing carbonic acid, and preparing oxygen for us, we begin to look upon it with some such indifference as upon a gasometer. It has become a machine; some of our sense of its happiness is gone; its emanation of inherent life is no longer pure." The knowledge of the anatomical structure of the limb is very interesting, but it adds nothing to the beauty of its outline. Scientific associations, however, of this kind, will have a different æsthetic effect, according to the degree or the enthusiasm with which the science has been studied.