Courbet.
XXII
Many people imagine that art is capable of an indefinite progress toward perfection. This is a mistake. There is a limit where it must stop. And for this reason: the conditions which govern the imitation of nature are fixed. The object is to produce a picture, that is to say, a plane surface either with or without a border, and on this surface the representation of something produced by the sole means of different colouring substances. Since it is obliged to remain thus circumscribed, it is easy to foresee the limit of perfectibility. When the picture has succeeded in satisfying our minds in all the conditions imposed on its production, it will cease to interest. Such is the fate of everything which has attained its end: we grow indifferent and abandon it.
In the conditions governing the production of the picture, every means has been explored. The most difficult problem was that of complete relief, depth of perspective carried to the point of perfect illusion. The stereoscope has solved the problem. It only remains now to combine this perfection with the other kinds of perfection already found. Let no man imagine that art, bound by these conditions of the plane surface, can ever free itself from the circle which limits it. It is easy to foresee that its last word will soon have been said.
Wiertz.
XXIII