§ 3. The exceeding nobility of these ideas.
Such are the function and force of ideas of relation. They are what I have asserted in the second chapter of this section to be the noblest subjects of art. Dependent upon it only for expression, they cause all the rest of its complicated sources of pleasure to take, in comparison with them, the place of mere language or decoration; nay, even the noblest ideas of beauty sink at once beside these into subordination and subjection. It would add little to the influence of Landseer's picture above instanced, Chap. II., § 4, that the form of the dog should be conceived with every perfection of curve and color which its nature was capable of, and that the ideal lines should be carried out with the science of a Praxiteles; nay, the instant that the beauty so obtained interfered with the impression of agony and desolation, and drew the mind away from the feeling of the animal to its outward form, that instant would the picture become monstrous and degraded. The utmost glory of the human body is a mean subject of contemplation, compared to the emotion, exertion and character of that which animates it; the lustre of the limbs of the Aphrodite is faint beside that of the brow of the Madonna; and the divine form of the Greek god, except as it is the incarnation and expression of divine mind, is degraded beside the passion and the prophecy of the vaults of the Sistine.
§ 4. Why no subdivision of so extensive a class is necessary.
Ideas of relation are of course, with respect to art generally, the most extensive as the most important source of pleasure; and if we proposed entering upon the criticism of historical works, it would be absurd to attempt to do so without further subdivision and arrangement. But the old landscape painters got over so much canvas without either exercise of, or appeal to, the intellect, that we shall be little troubled with the subject as far as they are concerned; and whatever subdivision we may adopt, as it will therefore have particular reference to the works of modern artists, will be better understood when we have obtained some knowledge of them in less important points.
By the term "ideas of relation," then, I mean in future to express all those sources of pleasure, which involve and require, at the instant of their perception, active exertion of the intellectual powers.