Since it is not the purpose of any art to represent mere things, but to express concrete "states of the soul," the center of which is always some feeling, exact fidelity in the representation of objects is not necessary for good painting or drawing. Only so much of things needs to be represented as is necessary to give back the life of them. Necessary above all is the object as a whole, for to this our feelings are attached; now this can usually be far better represented through an impressionistic sketch, which gives only the significant features, than by a painstaking and detailed drawing. Since, furthermore, the life of things can be conveyed through color and line as such, a certain departure from realism is legitimate for this end. Without some freedom from the exact truth of the colors and lines of things, the artist is unable to choose and compose them for expressive purposes; when exactly like the objects which they represent, they tend to lose all expressive power of their own, becoming mere signs or equivalents of things. A certain amount of variation from the normal may be necessary in order that the sense symbols shall call attention to themselves, in order that we be prevented, as we are not in the ordinary observation of nature, from looking through them to the things which they mean. Whenever, moreover, the artist wishes to render a unique reaction to a scene, he can do so only through a courageous use of the subtle language of color and line, which may require a distortion of the "real" local qualities of things; for, if he makes a plain, realistic copy of the scene itself, he can evoke, and so express, only the normal emotional responses to it.