The work of art must seize upon you, wrap you up in itself and carry you away. It is the means by which the artist conveys his passion. It is the current which he puts forth, which sweeps you along in his passion
The pain passes, the beauty remains.
In painting, as in the other arts, there's not a single process, no matter how insignificant, which can be reasonably made into a formula. You come to nature with your theories, and she knocks them all flat.
If the painter works directly from nature, he ultimately looks for nothing but momentary effects; he does not try to compose, and soon he gets monotonous.