Art, then, differs from morality, philosophy, love and religion, in that it presents directly to sense the variety in unity which they manifest only to the mind and spirit. Like them, it deals with life, but the unity that it attains by selection and exclusion is unlike their unity in being tangible. Made by man, it has this one supreme advantage, that it is adapted from the outset to his needs. What it cannot unify it can exclude. Though nature care nothing for the peculiarities of the eye, a landscape painter can omit a tree that upsets the balance of his composition. Actual men and women present all sorts of incongruities of figure, but the sculptor can suppress the stooping shoulders, the knobby hips, and the bandy legs. Language bristles with trivial and vulgar words, but no poet except Walt Whitman thinks it necessary to write about hatters, who cannot, according to Stevenson, «be tolerated in emotional verse.» Out of the infinite number of sounds that besiege our natural ears, musicians have selected about ninety definite tones, preordained to congruity, with which to weave their marvelous fabric. That is ever the method of art; it excludes the irrelevant or the discordant, in order to secure a salient and pure integrity. By sacrificing something of the richness of experience, it gains a rationality unknown in experience. Browning's Pippa is a gentle, noble soul, bringing goodness everywhere; in real life she would be a poor mill-girl insulted by a thousand sordid and accidental details. Shelley portrays Beatrice Cenci in the transfiguring light of poetic truth; actual experience would show her tortured by a sinister and ignoble fate. No Greek youth could have matched the perfect plastic beauty of the Disk-thrower, and no Italian woman ever symbolized cruel, sphinx-like loveliness as does the Mona Lisa. Corot's nature is grayer and softer and more harmonious than ever existed on earth. And such songs as Schumann's «Ich Grolle Nicht» and Tschaïkowsky's «Nur Wer die Sehnsucht Kennt» pulsate with a passion as intense but far less torn and fragmentary than that by which they were inspired. This serene perfection, which wraps like a mantle all works of genuine art, results from harmonious organization, and is attained only by excluding the irrelevancies always present in nature. Whistler is wise as well as witty when he exclaims that «to ask the painter to copy nature as he sees it is to invite the pianist to sit on the keyboard.» Were there, to be sure, a perfect adjustment between nature and our faculties, were we able to discern the unity that must exist even in the infinitely complex Whole of the world, then such a dictum would be outgrown, and selection would cease to be the procedure of art. But until we have grown to possess universal synthetic power art will have its solacing mission and its selective method as now.