“And this cannot be, just as there cannot be two men, or even two leaves on a tree, exactly alike. Still less can two works from different realms of art, the musical and the literary, be absolutely alike. If they coincide, then either one is a work of art and the other a counterfeit, or both are counterfeits. Two live leaves cannot be exactly alike, but two artificial leaves may be. And so it is with works of art. They can only coincide completely when neither the one nor the other is art, but only cunningly devised semblances of it.”