We all know that music is comprised of sound; however, many have argued that all sound is not music. Stravinsky advanced this view convincingly when he explained that when we simply hear the rustle of leaves or the sound of a brook, we are not hearing music nor are we utilizing musical ability to hear or even enjoy these sounds of nature. These sounds are “promises of music; it take a human being to keep them: a human being who is sensitive to natures many voices, of course, but who in addition feels the need of putting them in order and who is gifted for that task with a very special aptitude. In his hands all that I have considered as not being music will become music. From this I conclude that tonal elements become music only by virtue of their being organized, and that such organization presupposes a conscious human act.”
How do humans organize sound so that it becomes music? Stravinsky specifically mentions tonality, and that is one way in which we organize sound into music. Tonality is a culturally learned concept. Western cultures organize tones into major and minor tonalities, and less often into others such as Dorian or Mixolydian. Eastern cultures organize music into very different tonalities, but tonalities nonetheless. While Stravinsky’s observation of music as a human constructed entity, restricting ourselves to tonality will be of little help in a discussion of music and poetry, because poetry, as spoken language, has no tonality, at least in Western culture.
There are other ways that humans organize music. The two most significant ones are rhythm, meter, and phrases. These are elements that are critical to both music and poetry. In both disciplines, sounds are made that are of variable durations that are perceived in patterns. Whether we are performing a music, or reading aloud poetry, the notes or words respectively are heard in patterns of durations that we naturally form into groups of sounds that make sense to us, and make what would otherwise be a barrage of noise into intelligible and enjoyable art.
These rhythmic patterns in music, combined with tonal elements, result in musical phrases that end with a pause that marks the end of the phrase and signal the immanent beginning of the next phrase. An example of this is the famous “Ode to Joy” theme from Beethoven’s ninth symphony. The antecedent phrase ends with the longest duration heard thus far on a tone from the dominant chord, and the consequent phrase ends on a duration of equal length but on a tone from the tonic chord which in this case is also the tonic tone. That tonic note of finality punctuates the phrase with the musical equivalent of a period, whereas the end of the antecedent phrase on the dominant punctuates the phrase with the musical equivalent of a comma. Both phrases are of equal length and are comprised of identical rhythms. The structure provides a high degree of predictability that brings stability to our perception of the music. The effect is the same as a rhyme scheme in poetry. Rhythm, meter, and the rhyming pattern also bring predictability, at least that a rhyming word is coming, and of when the rhyme will occur within the established meter and rhyme scheme. In both music and poetry, when the predicted tone or rhyme, respectively, does not occur, tension is built; a tension that remains until the expectation is met.
There is an aspect of the similarity between music and poetry that goes beyond structure. I refer to the expressiveness humans achieve with both art forms. Leonard Bernstein discussed this extensively in his Norton Lecture, “The Unanswered Question” at Harvard University. Music can never have the literalness that language does, because no music has literal meaning. Musical meaning is always more abstract, and is come to through the interaction with not only the organizing mind, but the creative imagination. Prose, on the other hand, falls far short of such expressive abstraction, but not poetry. Poetry, like music, thrives on abstraction, illusion, and even at times whimsy. Poetry utilizes language in a way that replaces relative precision with literary suggestion that appeals to the human imagination.
If you are interested in reading more on this subject, I suggest Poetics of Music in the Form of Six Lessons by Igor Stravinsky, and The Unanswered Question by Leonard Bernstein. Both were lectures later published that each gave when they were honored with the Charles Eliot Norton chair at Harvard University.