7. But over this triple division there must rule another yet more important. Any of these three arts may be either imitative of natural objects or limited to useful appliance. You may either paint a picture that represents a scene, or your street door, to keep it from rotting; you may mold a statue, or a plate; build the resemblance of a cluster of lotus stalks, or only a square pier. Generally speaking, Painting and Sculpture will be imitative, and Architecture merely useful; but there is a great deal of Sculpture--as this crystal ball,[6] for instance, which is not imitative, and a great deal of architecture which, to some extent, is so, as the so-called foils of Gothic apertures; and for many other reasons you will find it necessary to keep distinction clear in your minds between the arts--of whatever kind--which are imitative, and produce a resemblance or image of something which is not present; and those which are limited to the production of some useful reality, as the blade of a knife, or the wall of a house. You will perceive also, as we advance, that sculpture and painting are indeed in this respect only one art; and that we shall have constantly to speak and think of them as simply _graphic_, whether with chisel or color, their principal function being to make us, in the words of Aristotle, "[Greek: theoretikoi tou peri somata kallous]" (Polit. 8. 3), "having capacity and habit of contemplation of the beauty that is in material things;" while architecture, and its correlative arts, are to be practiced under quite other conditions of sentiment. 8. Now it is obvious that so far as the fine arts consist either in imitation or mechanical construction, the right judgment of them must depend on our knowledge of the things they imitate, and forces they resist: and my function of teaching here would (for instance) so far resolve itself, either into demonstration that this painting of a peach[7] does resemble a peach, or explanation of the way in which this plowshare (for instance) is shaped so as to throw the earth aside with least force of thrust. And in both of these methods of study, though of course your own diligence must be your chief master, to a certain extent your Professor of Art can always guide you securely, and can show you, either that the image does truly resemble what it attempts to resemble, or that the structure is rightly prepared for the service it has to perform. But there is yet another virtue of fine art which is, perhaps, exactly that about which you will expect your Professor to teach you most, and which, on the contrary, is exactly that about which you must teach yourselves all that it is essential to learn. [Illustration: FIG. 1]