The beauty in still-life paintings may arise from several causes, namely, the pleasure experienced from the excellence of the imitation; the harmony of tones; the beauty of the things imitated; the association of ideas; and the pleasure derived from the acquisition of knowledge. Aristotle seemed to think this last one of the principal reasons for our appreciation of the painter's work, though he agreed that the better the imitation, the greater the pleasure to the observer. The argument appears to apply particularly to the lower forms of life because in nature they are not often closely examined. A cauliflower for instance may be seen a thousand times by one who would not carefully note its structure, but if he see an imitation of it painted by a good artist, his astonishment at the excellence of the imitation might cause him to observe the representation closely, and learn much about the vegetable which he did not know before. In this way the information gained would add to his pleasure. As in landscape, from the absence of abstract qualities from the things represented, and since the position of the signs may be indefinitely varied without a sense of incongruity resulting, there can be no ideal in still-life, and so the painter cannot pass beyond experience without achieving the abnormal. The painter of still-life has the choice of four kinds of imitation, namely, the representation of products of nature which are in themselves beautiful, as roses and fine plumaged birds; the imitation of products of human industry which are in themselves beautiful, as sculptured plate or fine porcelain; the representation of natural and manual products which in themselves are neither beautiful nor displeasing, but interest from association of ideas, as certain fruits, books, and musical instruments; and the imitation of things which in themselves are not pleasing to the sight, as dead game, kitchen utensils, and so on. Obviously the artist may assort any two or more of these varieties in the same picture. He may also associate them with life, but here he is met with a grave difficulty which goes to the very root of art. If two forms, not being merely accessories, are associated together in a design, the lower form must necessarily be subordinated, otherwise the mind of the observer will be disturbed by the apparent double objective. A live dog or other animal in a still-life composition will immediately attract the eye of the observer, drawing off his attention from the inanimate objects represented, which will consequently thereafter lose much of their interest. The presence of a man is still worse. Not only is it natural and inevitable that a human being should take precedence of whatever is inanimate in a work of art, but in the case of still-life, where he is painted of natural size, he must necessarily overshadow everything else in the picture. Further, his own representation is much injured because the surroundings exercise a