And apart from this we shall find the restriction to the beauty of art only natural, for in so far as the beauties of Nature may have come under discussion--a rarer occurrence among ancient writers than among ourselves--yet at least it has occurred to no one to insist emphatically on the beauty of natural objects to the extent of proposing a science, or systematic exposition of such beauties. It is true that the point of view of _utility_ has been selected for such exclusive treatment. We have, for example, the conception of a science of natural objects in so far as they are useful in the conflict with diseases, in other words a description of minerals, chemical products, plants, animals, which subserve the art of healing. We do not find any analogous exploitation and consideration of the realm of Nature in its aspect of beauty. In the case of natural beauty we are too keenly conscious that we are dealing with an indefinite subject-matter destitute of any real criterion. It is for this reason that such an effort of comparison would carry with it too little interest to justify the attempt. These preliminary observations over beauty in Nature and art, over the relation of both, and the exclusion of the first-mentioned from the province of our real subject-matter are intended to disabuse us of the notion that the limitation of our science is simply a question of capricious selection. We have, however, not reached the point where a _demonstration_ of this fact is feasible for the reason that such an investigation falls within the limits of our science itself, and it is therefore only at a later stage that we can either discuss or prove the same. Assuming, however, that we have, by way of prelude, limited our inquiry to the beauty of art, we are merely by this first step involved in fresh difficulties.