In his contact with the external world the artist identifies himself with his object. If he is painting a tree he in a measure becomes the tree; he values it at all because it expresses for him concretely what he feels in its presence. The object and his spirit fuse; and through the fusion they together grow into a new and larger unity. What his work expresses is not the object for its own sake but this larger unity of his identity with it. To appreciate the artist's work, therefore, we must in our turn merge ourselves in his emotion, and becoming one with it, so extend our personality into larger life. To make the artist's emotion our own, to identify ourselves with the object which he presents to us, we must pass beyond the material form in which the work is embodied, letting the spirit and meaning of it speak to our spirit. In itself an individual picture or statue or symphony is an objective, material thing, received into consciousness along the channel of the senses; but its origin and its end alike are in emotion. The material form, whether in nature or in works of art, is only the means by which the emotion is communicated. A landscape in nature is composed of meadow and hills, blue sky and tumbling clouds; these are the facts of the landscape. But they are not fixed and inert. The imagination of the beholder combines these elements into a harmony of color and mass; his spirit flows into consonance with the harmony his imagination has compelled out of nature, becoming one with it. To regard the world not as facts and things, but as everywhere the stimulus of feeling, feeling which becomes our own experience, is the condition of appreciation.