In the opening chapter, he draws a connection between poetry and music, arguing that poetry is rhythmic, melodious, and serves as a form of music. I couldn't agree more. Here's the way he states it:
[W]hatever its form, written poetry is characterized by a kind of music. Accent structures in words naturally make a sort of melody. In the word melody itself the first syllable is stressed, which makes it louder than the others, and most native English speakers will give it a higher pitch than other syllables. The word melody has a melody! Good poetry plays with speech sounds to create a pleasing set of pitch patterns, and good poetry contains rhythmic groupings that are songlike. When a poem succeeds, it is a sensual experience - the way the words feel in the mouth of the speaker and the way they sound in the ears of the hearer are part of the encounter. Unlike prose, most poems ask to be read aloud. This is why poetry lovers usually do so. Just reading the poem is not enough. The reader needs to feel the rhythms.
--Daniel J. Levitin, The World in Six Songs
