What is music about? What, as Plato would say, does it imitate? Our experience of Time in its twofold aspect, natural or organic repetition, and historical novelty created by choice. And the full development of music as an art depends upon a recognition that these two aspects are different and that choice, being an experience confined to man, is more significant than repetition. A succession of two musical notes is an act of choice; the first causes the second, not in the scientific sense of making it occur necessarily, but in the historical sense of provoking it, of providing it with a motive for occurring. A successful melody is a self-determined history; it is freely what it intends to be, yet is a meaningful whole, not an arbitrary succession of notes.
— W. H. Auden, from The Dyer’s Hand