Math is music. Music is math.
The idea that math and music are closely related was first introduced to me by Enid Blyton's Malory Towers series—which I read during my middle school years. One of the major recurring characters in the story is Irene, a scatterbrained comedic relief who is nontheless a genius in both maths and music.
She once mentioned that her two areas of expertise are really quite similar, to the befuddlement of the other girls. "How?" they wondered, "Math is so dull, and music so lovely!"
But, as I became more familiar with both, I began to realize how much these two domains are indeed closely related. Music is inherently mathematical, and its components—pitch, tempo, chord progression, etc.—can all be expressed in numbered ratios.
In fact, ancient civilizations have long studied the relationship of mathematics and sound (music). The Pythagoreans, while investigating the numerical ratios of musical scales, concluded thusly: "All nature consists of harmony arising out of numbers"
Math & Music: Poetry's Heartbeat
This relationship between math and music naturally flows into poetry.
Often described as "music in words," ancient poets used to sing their verses, translating meter and diction to pitch, rhythms and time signatures.
Perhaps this is also why many classical forms of poetry, such as haiku and sonnets, are confined by strict syllable counts or rhythmic patterns; even modern forms of poetry invented more recently are directly inspired by mathematical concepts (e.g. Fibonacci) and structural geometry (e.g. Parallelogram de Crystalline).
Meanwhile, literary and rhetorical techniques (e.g. rhymes, repetition, aphorism, alliteration, assonance, consonance, symmetry and volta) form specific acoustic patterns that mirror musical harmony.
In short, the language of poetry is the loom that weaves mathematical precision (through meters and line counts) with musical expressions (through tone and sound) into one tapestry.
Stepping into the Rhythm
I used to think that poetries are defined by rhymes. Without it, they are just prose or statements with line breaks.
But as I became more familiar with the many different kinds of unrhymed poetry—etheree, lanterne, blitz, ekphraisis, shadorma, etc.—I realize that poetry is much more than just how the lines sound when they end.
Instead, the rise and fall of syllables, the ebb and flow of breath between phrases, the strategically placed pauses (caesura) that pave each line, is what gives poetry its voice.
"It's the journey that counts," in other words. Not just the bulls eye where the words must land; but the grace of its entire arc, where the rhythm, structure, and meaning align.