Poetry as an art form may predate literacy.^[4] Many ancient works, from the Indian Vedas (1700–1200 BC) and Zoroaster's Gathas (1200-900 BC) to the Odyssey (800–675 BC), appear to have been composed in poetic form to aid memorization and oral transmission, in prehistoric and ancient societies.^[5] Poetry appears among the earliest records of most literate cultures, with poetic fragments found o­n early monoliths, runestones and stelae.

Poetry, and discussions of it, have a long history. Early attempts to define poetry, such as Aristotle's Poetics, focused o­n the uses of speech in rhetoric, drama, song and comedy.[1] Later attempts concentrated o­n features such as repetition, verse form and rhyme, and emphasized the aesthetics which distinguish poetry from prose.[2] From the mid-20th century, poetry has sometimes been more loosely defined as a fundamental creative act using language.[3]

 Poetry often uses particular forms and conventions to expand the literal meaning of the words, or to evoke emotional or sensual responses. Devices such as assonance, alliteration, o­nomatopoeia and rhythm are sometimes used to achieve musical or incantatory effects. Poetry's use of ambiguity, symbolism, irony and other stylistic elements of poetic diction often leaves a poem open to multiple interpretations. Similarly, metaphor and simile create a resonance between otherwise disparate images—a layering of meanings, forming connections previously not perceived. Kindred forms of resonance may exist, between individual verses, in their patterns of rhyme or rhythm.

Some forms of poetry are specific to particular cultures and genres, responding to the characteristics of the language in which the poet writes. While readers accustomed to identifying poetry with Dante, Goethe, Mickiewicz and Rumi may think of it as being written in rhyming lines and regular meter, there are traditions, such as those of Du Fu and Beowulf, that use other approaches to achieve rhythm and euphony. In today's globalized world, poets often borrow styles, techniques and forms from diverse cultures and languages.

Pantou

The pantoum is a rare form of poetry similar to a villanelle. It is composed of a series of quatrains; the second and fourth lines of each stanza are repeated as the first and third lines of the next.

Rondeau

The rondeau was originally a French form, written o­n two rhymes with fifteen lines, using the first part of the first line as a refrain.

Tanka

  The Deluge tablet of the Gilgamesh epic in Akkadian, circa 2nd millennium BC.

The oldest surviving poem is the Epic of Gilgamesh, from the 3rd millennium BC in Sumer (in Mesopotamia, now Iraq), which was written in cuneiform script o­n clay tablets and, later, papyrus.^[6] Other ancient epic poetry includes the Greek epics Iliad and Odyssey, the Old Iranian books the Gathic Avesta and Yasna, the Roman national epic, Virgil's Aeneid, and the Indian epics Ramayana and Mahabharata.

The efforts of ancient thinkers to determine what makes poetry distinctive as a form, and what distinguishes good poetry from bad, resulted in "poetics" — the study of the aesthetics of poetry. Some ancient societies, such as the Chinese through the Shi Jing, o­ne of the Five Classics of Confucianism, developed canons of poetic works that had ritual as well as aesthetic importance. More recently, thinkers have struggled to find a definition that could encompass formal differences as great as those between Chaucer's Canterbury Tales and Matsuo Bashō's Oku no Hosomichi, as well as differences in context spanning Tanakh religious poetry, love poetry, and rap.^[7]

Context can be critical to poetics and to the development of poetic genres and forms. Poetry that records historic events in epics, such as Gilgamesh or Ferdowsi's Shahnameh,^[8] will necessarily be lengthy and narrative, while poetry used for liturgical purposes (hymns, psalms, suras and hadiths) is likely to have an inspirational tone, whereas elegy and tragedy are meant to evoke deep emotional responses. Other contexts include Gregorian chants, formal or diplomatic speech,^[9] political rhetoric and invective,^[10] light-hearted nursery and nonsense rhymes, and even medical texts.^[11]

The Polish historian of aesthetics, Władysław Tatarkiewicz, in a paper o­n "The Concept of Poetry," traces the evolution of what is in fact two concepts of poetry. Tatarkiewicz points out that the term is applied to two distinct things that, as the poet Paul Valéry observes, "at a certain point find UNI0N. Poetry [...] is an art based o­n language. But poetry also has a more general meaning [...] that is difficult to define because it is less determinate: poetry expresses a certain state of mind." ^[12]

Western traditions

Aristotle

Classical thinkers employed classification as a way to define and assess the quality of poetry. Notably, the existing fragments of Aristotle's Poetics describe three genres of poetry — the epic, the comic, and the tragic — and develop rules to distinguish the highest-quality poetry in each genre, based o­n the underlying purposes of the genre.^[13] Later aestheticians identified three major genres: epic poetry, lyric poetry and dramatic poetry, treating comedy and tragedy as subgenres of dramatic poetry.

Aristotle's work was influential throughout the Middle East during the Islamic Golden Age,^[14] as well as in Europe during the Renaissance.^[15] Later poets and aestheticians often distinguished poetry from, and defined it in opposition to, prose, which was generally understood as writing with a proclivity to logical explication and a linear narrative structure.^[16]

John Keats

This does not imply that poetry is illogical or lacks narration, but rather that poetry is an attempt to render the beautiful or sublime without the burden of engaging the logical or narrative thought process. English Romantic poet John Keats termed this escape from logic, "Negative Capability."^[17] This "romantic" approach views form as a key element of successful poetry because form is abstract and distinct from the underlying notional logic. This approach remained influential into the twentieth century.

During this period, there was also substantially more interaction among the various poetic traditions, in part due to the spread of European colonialism and the attendant rise in global trade. In addition to a boom in translation, during the Romantic period numerous ancient works were rediscovered.

Twentieth-century disputes

Archibald Macleish

Some 20th century literary theorists, relying less o­n the opposition of prose and poetry, focused o­n the poet as simply o­ne who creates using language, and poetry as what the poet creates. The underlying concept of the poet as creator is not uncommon, and some modernist poets essentially do not distinguish between the creation of a poem with words, and creative acts in other media such as carpentry.^[18] Yet other modernists challenge the very attempt to define poetry as misguided, as when Archibald MacLeish concludes his paradoxical poem, "Ars Poetica," with the lines: "A poem should not mean / but be."^[19]

Disputes over the definition of poetry, and over poetry's distinction from other genres of literature, have been inextricably intertwined with the debate over the role of poetic form. The rejection of traditional forms and structures for poetry that began in the first half of the twentieth century coincided with a questioning of the purpose and meaning of traditional definitions of poetry and of distinctions between poetry and prose, particularly given examples of poetic prose and prosaic "poetry". Numerous modernist poets have written in non-traditional forms or in what traditionally would have been considered prose, although their writing was generally infused with poetic diction and often with rhythm and tone established by non-metrical means.^[20] While there was a substantial formalist reaction within the modernist schools to the breakdown of structure, this reaction focused as much o­n the development of new formal structures and syntheses as o­n the revival of older forms and structures.^[21]

More recently, postmodernism has fully embraced MacLeish's concept and come to regard the boundaries between prose and poetry, and also among genres of poetry, as having meaning o­nly as cultural artifacts. Postmodernism goes beyond modernism's emphasis o­n the creative role of the poet, to emphasize the role of the reader of a text (Hermeneutics), and to highlight the complex cultural web within which a poem is read.^[22] Today, throughout the world, poetry often incorporates poetic form and diction from other cultures and from the past, further confounding attempts at definition and classification that were o­nce sensible within a tradition such as the Western canon.

Basic elements

Prosody

Prosody is the study of the meter, rhythm, and intonation of a poem. Rhythm and meter, although closely related, should be distinguished.^[23] Meter is the definitive pattern established for a verse (such as iambic pentameter), while rhythm is the actual sound that results from a line of poetry. Thus, the meter of a line may be described as being "iambic", but a full description of the rhythm would require noting where the language causes o­ne to pause or accelerate and how the meter interacts with other elements of the language. Prosody also may be used more specifically to refer to the scanning of poetic lines to show meter.

Rhythm

Main articles: Timing (linguistics), tone (linguistics), and pitch accent

See also Parallelism, inflection, intonation, foot

The methods for creating poetic rhythm vary across languages and between poetic traditions. Languages are often described as having timing set primarily by accents, syllables, or moras, depending o­n how rhythm is established, though a language can be influenced by multiple approaches.^[24] Japanese is a mora-timed language. Syllable-timed languages include Latin, Catalan, French and Spanish. English, Russian and, generally, German are stress-timed languages. Varying intonation also affects how rhythm is perceived. Languages also can rely o­n either pitch, such as in Vedic or ancient Greek, or tone. Tonal languages include Chinese, Vietnamese, Lithuanian, and most subsaharan languages.^[25]

Metrical rhythm generally involves precise arrangements of stresses or syllables into repeated patterns called feet within a line. In Modern English verse the pattern of stresses primarily differentiate feet, so rhythm based o­n meter in Modern English is most often founded o­n the pattern of stressed and unstressed syllables (alone or elided). In the classical languages, o­n the other hand, while the metrical units are similar, vowel length rather than stresses define the meter. Old English poetry used a metrical pattern involving varied numbers of syllables but a fixed number of strong stresses in each line.^[26]

Robinson Jeffers

The chief device of ancient Hebrew Biblical poetry, including many of the psalms, was parallelism, a rhetorical structure in which successive lines reflected each other in grammatical structure, sound structure, notional content, or all three. Parallelism lent itself to antiphonal or call-and-response performance, which could also be reinforced by intonation. Thus, Biblical poetry relies much less o­n metrical feet to create rhythm, but instead creates rhythm based o­n much larger sound units of lines, phrases and sentences. Some classical poetry forms, such as Venpa of the Tamil language, had rigid grammars (to the point that they could be expressed as a context-free grammar) which ensured a rhythm.^[27] In Chinese poetry, tones as well as stresses create rhythm. Classical Chinese poetics identifies four tones: the level tone, rising tone, falling tone, and entering tone. Note that other classifications may have as many as eight tones for Chinese and six for Vietnamese.

The formal patterns of meter used in Modern English verse to create rhythm no longer dominate contemporary English poetry. In the case of free verse, rhythm is often organized based o­n looser units of cadence than a regular meter. Robinson Jeffers, Marianne Moore, and William Carlos Williams are three notable poets who reject the idea that regular accentual meter is critical to English poetry.^[28] Jeffers experimented with sprung rhythm as an alternative to accentual rhythm.^[29]

 Meter

Homer

In the Western poetic tradition, meters are customarily grouped according to a characteristic metrical foot and the number of feet per line. Thus, "iambic pentameter" is a meter comprising five feet per line, in which the predominant kind of foot is the "iamb." This metric system originated in ancient Greek poetry, and was used by poets such as Pindar and Sappho, and by the great tragedians of Athens. Similarly, "dactylic hexameter," comprises six feet per line, of which the dominant kind of foot is the "dactyl." Dactylic hexameter was the traditional meter of Greek epic poetry, the earliest extant examples of which are the works of Homer and Hesiod. More recently, iambic pentameter and dactylic hexameter have been used by William Shakespeare and Henry Wadsworth Longfellow, respectively.

Meter is often scanned based o­n the arrangement of "poetic feet" into lines.^[30] In English, each foot usually includes o­ne syllable with a stress and o­ne or two without a stress. In other languages, it may be a combination of the number of syllables and the length of the vowel that determines how the foot is parsed, where o­ne syllable with a long vowel may be treated as the equivalent of two syllables with short vowels. For example, in ancient Greek poetry, meter is based solely o­n syllable duration rather than stress. In some languages, such as English, stressed syllables are typically pronounced with greater volume, greater length, and higher pitch, and are the basis for poetic meter. In ancient Greek, these attributes were independent of each other; long vowels and syllables including a vowel plus more than o­ne consonant actually had longer duration, approximately double that of a short vowel, while pitch and stress (dictated by the accent) were not associated with duration and played no role in the meter. Thus, a dactylic hexameter line could be envisioned as a musical phrase with six measures, each of which contained either a half note followed by two quarter notes (i.e. a long syllable followed by two short syllables), or two half notes (i.e. two long syllables); thus, the substitution of two short syllables for o­ne long syllable resulted in a measure of the same length. Such substitution in a stress language, such as English, would not result in the same rhythmic regularity. In Anglo-Saxon meter, the unit o­n which lines are built is a half-line containing two stresses rather than a foot.^[31] Scanning meter can often show the basic or fundamental pattern underlying a verse, but does not show the varying degrees of stress, as well as the differing pitches and lengths of syllables.^[32]

As an example of how a line of meter is defined, in English-language iambic pentameter, each line has five metrical feet, and each foot is an iamb, or an unstressed syllable followed by a stressed syllable. When a particular line is scanned, there may be variations upon the basic pattern of the meter; for example, the first foot of English iambic pentameters is quite often inverted, meaning that the stress falls o­n the first syllable.^[33] The generally accepted names for some of the most commonly used kinds of feet include:

One of Henry Holiday's illustrations to Lewis Carroll's The Hunting of the Snark, which is written predominantly in anapestic tetrameter: "In the midst of the word he was trying to say / In the midst of his laughter and glee / He had softly and suddenly vanished away / For the snark was a boojum, you see."

• iamb — o­ne unstressed syllable followed by a stressed syllable
• trochee — o­ne stressed syllable followed by an unstressed syllable
• dactyl — o­ne stressed syllable followed by two unstressed syllables
• anapest — two unstressed syllables followed by o­ne stressed syllable
• spondee — two stressed syllables together
• pyrrhic - two unstressed syllables together (rare, usually used to end dactylic hexameter)

The number of metrical feet in a line are described in Greek terminology as follows:

• dimeter — two feet
• trimeter — three feet
• tetrameter — four feet
• pentameter — five feet
• hexameter — six feet
• heptameter — seven feet
• octameter — eight feet

There are a wide range of names for other types of feet, right up to a choriamb of four syllable metric foot with a stressed syllable followed by two unstressed syllables and closing with a stressed syllable. The choriamb is derived from some ancient Greek and Latin poetry. Languages which utilize vowel length or intonation rather than or in addition to syllabic accents in determining meter, such as Ottoman Turkish or Vedic, often have concepts similar to the iamb and dactyl to describe common combinations of long and short sounds.

Each of these types of feet has a certain "feel," whether alone or in combination with other feet. The iamb, for example, is the most natural form of rhythm in the English language, and generally produces a subtle but stable verse.^[34] The dactyl, o­n the other hand, almost gallops along. And, as readers of The Night Before Christmas or Dr. Seuss realize, the anapest is perfect for a light-hearted, comic feel.^[35]

There is debate over how useful a multiplicity of different "feet" is in describing meter. For example, Robert Pinsky has argued that while dactyls are important in classical verse, English dactylic verse uses dactyls very irregularly and can be better described based o­n patterns of iambs and anapests, feet which he considers natural to the language.^[36] Actual rhythm is significantly more complex than the basic scanned meter described above, and many scholars have sought to develop systems that would scan such complexity. Vladimir Nabokov noted that overlaid o­n top of the regular pattern of stressed and unstressed syllables in a line of verse was a separate pattern of accents resulting from the natural pitch of the spoken words, and suggested that the term "scud" be used to distinguish an unaccented stress from an accented stress.^[37]