Phonology

Phonology is typically distinguished from phonetics, which concerns the physical production, acoustic transmission and perception of the sounds or signs of language.

Nikolai Trubetzkoy in Grundzüge der Phonologie (1939) defines phonology as "the study of sound pertaining to the system of language," as opposed to phonetics, which is "the study of sound pertaining to the act of speech" (the distinction between language and speech being basically Ferdinand de Saussure's distinction between langue and parole).

[7] Early evidence for a systematic study of the sounds in a language appears in the 4th century BCE Ashtadhyayi, a Sanskrit grammar composed by Pāṇini.

[11] Baudouin de Courtenay's subsequent work, though often unacknowledged, is considered to be the starting point of modern phonology.

One of its leading members was Prince Nikolai Trubetzkoy, whose Grundzüge der Phonologie (Principles of Phonology),[6] published posthumously in 1939, is among the most important works in the field from that period.

Louis Hjelmslev's glossematics also contributed with a focus on linguistic structure independent of phonetic realization or semantics.

[9]: 175 In 1968, Noam Chomsky and Morris Halle published The Sound Pattern of English (SPE), the basis for generative phonology.

Ordered phonological rules govern how underlying representation is transformed into the actual pronunciation (the so-called surface form).

Prominent figures in this field include Jonathan Kaye, Jean Lowenstamm, Jean-Roger Vergnaud, Monik Charette, and John Harris.

The appeal to phonetic grounding of constraints and representational elements (e.g. features) in various approaches has been criticized by proponents of "substance-free phonology", especially by Mark Hale and Charles Reiss.

However, English speakers intuitively treat both sounds as variations (allophones, which cannot give origin to minimal pairs) of the same phonological category, that is of the phoneme /p/.

(Traditionally, it would be argued that if an aspirated [pʰ] were interchanged with the unaspirated [p] in spot, native speakers of English would still hear the same words; that is, the two sounds are perceived as "the same" /p/.)

The presence or absence of minimal pairs, as mentioned above, is a frequently used criterion for deciding whether two sounds should be assigned to the same phoneme.

The findings and insights of speech perception and articulation research complicate the traditional and somewhat intuitive idea of interchangeable allophones being perceived as the same phoneme.

In addition to the minimal units that can serve the purpose of differentiating meaning (the phonemes), phonology studies how sounds alternate, or replace one another in different forms of the same morpheme (allomorphs), as well as, for example, syllable structure, stress, feature geometry, tone, and intonation.

The principles of phonological analysis can be applied independently of modality because they are designed to serve as general analytical tools, not language-specific ones.

Nikolai Trubetzkoy, 1920s
The vowels of modern (Standard) Arabic (left) and (Israeli) Hebrew (right) from the phonemic point of view. Note the intersection of the two circles—the distinction between short a , i and u is made by both speakers, but Arabic lacks the mid articulation of short vowels, while Hebrew lacks the distinction of vowel length.
The vowels of modern (Standard) Arabic and (Israeli) Hebrew from the phonetic point of view. The two circles are totally separate—none of the vowel-sounds made by speakers of one language is made by speakers of the other.