1
Repetition sometimes works in poetry, but rarely in prose. The musical provocateur John Cage once wrote a lecture in which a single page was repeated fourteen times, with the refrain "If anybody is sleep let him go to sleep" (Cage, 1961). Midway through, the artist Jean Reynal stood up and screamed, "John, I dearly love you, but I can't bear another minute.Gary F. Marcus
2
Sometimes guitar riffs get repeated over and over ("vamping, " in the lingo of musicians), but generally there is a soloist proving variation that runs above that background, lest the song sound monotonous. Philip Glass's minimalist compositions (such as the soundtrack to 'Koyaanisqatsi') deviate from much of the classical music that preceded them, with much less obvious movement than, say, the Romantic-era compositions that his work seems to rebel against, yet his works, too, consist not only of extensive repetition but also of constant (though subtle) variation. Virtually every song you've ever heard consists of exactly that: themes that recur over and over, overlaid with variations.Gary F. Marcus
3
Our sense of a composition largely inheres in how we feel about the individual parts; narrative arcs are almost always essential in drama but (unless there are lyrics involved) often less essential in music. All of this is, I suspect, again symptomatic of human memory limitations. We live, to a remarkable degree, in the present; what happened thirty seconds ago is already rapidly fading from our memory (or at least rapidly becomes harder for us to retrieve).Gary F. Marcus
4
But nobody is born being able to hear [intervals], and many people never master them. Some people never even notice that "Twinkle, Twinkle, Little Star" and "The Alphabet Song" follow the same melody (and hence consist of the same sequence of intervals).Gary F. Marcus