Since the dawn of human language, people have used rhythmic arrangements of words to convey special meanings. The use of rhythm is something that poetry and song have in common. In both cases, rhythm contributes to the way that meaning is organized and offered. Rhythm, or meter, helped oral poets remember the next line as they orated, and for both ancient audiences and modern readers, rhythm in poetry contributes to the overall pleasure of poetry.
As with songs, poets from many cultures writing in a wide range of traditions use rhythm, or meter, to lend a musicality to their words. Sometimes, this is evident in a refrain that is rhythmically identical each time it occurs, though some of the words might be different. As well, the particular arrangement of short or long syllabic stresses can give rhythm in poetry a nonverbal subtext; for example, a line that contains plodding, long syllables will sound dirgelike, while one that plays triplets that stress the first sound will seem tumbling and playful.
Many types of formal poetry impose a particular rhythm within the lines of a poem. For example, a sonnet, by definition, is a 16-line poem composed in iambic pentameter. Pentameter refers to a line of poetry that contains five feet, or beats. Iambs stress every other syllable; a famous example is found in Shakespeare’s Sonnet 18, which begins: “Shall I compare thee to a summer’s day?” Writing a successful poem whose form requires rhythmic consistency is a sign of a poet’s brilliance.
To the ancient Greeks, though, rhythm in poetry served a very practical purpose. Most of their poems were very long narratives that recounted events that occurred to many characters over a great many years, which meant it could be very difficult to remember the finer points. Certain rhythms helped orators mentally group events and ideas, thus contributing to their ability to recall what came next in the poems. Griots, West African poets who come from a tradition that is both ancient and modern, recount genealogies that stretch many generations into the past. Information for a multitude of families is most easily mentally retained by organizing it rhythmically.
As any child knows, rhythm in poetry adds to the delight. Just as children love to bounce, dance, and clap along with a favorite poem, adults, too, find increased pleasure in poetry’s reliable beats as well as its occasional rhythmic surprises. Patterns of stressed and unstressed syllables set up subconscious expectations in a listener or reader. When those expectations are met, it produces a sense of security; when those expectations are turned upside down by an unexpected rhythm that breaks the beat, it results in unexpected delight.