The representation of space, which painting alone of all the arts can achieve, does not imply, however, a representation of the full plastic quality of individual objects, which is the function of sculpture. This, to be sure, can be done in painting, as the great sculptor-painters of the Renaissance have shown; but it cannot be done so well as in sculpture; and when done tends to interfere with other things. It makes objects stand out too much by themselves, destroying their felt unity with other elements on the canvas, so that when provided with all the colors of life, they seem rather real than painted, and look as if they wished to leave the world of representation, where they belong, and touch hands with the spectator. The depth and the extent of space, the distance and the distribution of objects, light and shade and air, are all independent of the plasticity of individual things, which tends to disappear in proportion as they are emphasized. Only when attention is directed to the individual object does its full plasticity appear; see it as an element of the environing whole, and it flattens out to view. There are, in fact, two ways of seeing, to each of which corresponds a mode of painting. On the one hand, we may see distributively, holding objects as individuals each in our attention, neglecting light and space and air. Or else we may see synthetically, first the whole which light and space and air compose, and then individual things as bearers of these. The one is the more practical way of seeing; because, for practical purposes, the separate thing that can be grasped and used is all important, and the film of light and air and the neighborhood of other things are of no account. The other is more theoretical and sthetic; for to a pure vision which does not think of handling, there are no separate things, but only differences of shape and color and location in a single object, the visible whole. [Footnote: Cf. Lipps, _Aesthetik_, Bd. 2, s. 165, et seq.]