City of God
I bookmarked this when I read that book a few days ago, meaning to quote it here:
Yet science teaches us something about song: Scientific formulas describe the laws by which the universe operates and suggest in equations that a balance is possible even if things are in apparent imbalance. So do songs. Songs are compensatory. When a singer asks, Why did you do this to me, why did you break my heart . . . the inhering formula is that the degree of betrayal is equivalent to the eloquence of the cry of pain. [...] And when a song is good, a standard, we recognize it as expressing a truth. Like a formula, it can apply to everyone, not just the singer.
This passage actually has relatively little to do with the rest of the book, although it does suggest a connection between a couple of themes which do show up repeatedly.
