5. Feature theory. The system of phonological oppositions.

Phonology can be viewed as a product of the grammaticalization of real-world observations as filtered through the cognitive-perceptual system, thus as a "grammar of speech sounds".  From this point of view its organization mirrors that of grammar as a whole:

Grammar as a whole:	Phonology:
Lexicon	Features
Morphology	Geometry
Syntax	Phonotactics
Semantics	Phonetic interpretation

Phonology thus contains a lexicon of elementary terms (features), a morphology stating how features are combined into segments (geometry), a syntax specifying how segments align with each other (phonotactic principles, notably sonority), and a semantics indicating how these formal constructions are interpreted in speech output (phonetic interpretation).  

Within this overall organization, features play a central role as the ultimate constitutive elements of phonological representation:

 Features are universal in the sense that all languages define their speech sounds in terms of a small feature set.

 Features are distinctive in that they commonly distinguish one phoneme from another.

 Features delimit the number of theoretically possible speech sound contrasts within and across languages.

 Features are economical in allowing relatively large phoneme systems to be defined in terms of a much smaller feature set.

 Features define natural classes of sounds observed in recurrent phonological patterns.   

 Patterns of markedness, underlying crosslinguistic universals, involve the distinction between marked and unmarked features.

Although features must be defined in terms abstract enough to account for these various roles, they are ultimately grounded in cognitive and peripheral properties of the human organism.  We are currently exploring a model which views all features as grounded in quantal relations between articulatory movements and their acoustic effects.

The theory of distinctive features includes the following important items:

• features, and not phonemes, are fundamental units of linguistic analysis;

• constituents of signs do not have to be linearly arranged;

• language has an essentially spoken character: signifiants are to be found in the structuring of sounds;

• a small universal set of distinctive features functions to differentiate signifiants in natural languages;

• features can be defined both in articulatory and acoustic terms;

• they are realized on the surface.

The phoneme is functional because it functions to make one word or its grammatical form distinct from the other; it functions because it constitutes words; and because due to the fact that it really functions we recognize words (even though they are not pronounced properly). Phoneme manifests itself in a certain pattern of distribution. The patterns of distribution may be different. The simplest is free variation – the variation of one and the same phoneme pronounced by the same or different speaker. E.g.: phoneme /k/ pronounced with different degrees of aspiration which doesn’t affect the differentiatory properties of this phoneme.

Complementary distribution is another pattern of phoneme environment – when one sound occurs in different environments, it is supposed to be one phoneme which manifests itself in the form of different allophones. Sounds are in contrastive distribution when we find them in contrasted pairs: said-sad, bed-bad, take-cake.

Phonemes are discovered by the method of minimal pairs, or by distinctive oppositions. This method consists in finding as many pairs of words as possible which differ in one phoneme. The substitution of one sound for another is called commutation test. If such substitution results in the change of meaning, the commuted sounds are different phonemes. The method of distinctive oppositions proves whether the phonemic difference is relevant or not. E.g.: /t/ is a forelingual, plosive, occlusive, voiceless, fortis phoneme. /d/ is also a forelingual plosive occlusive but voiced lenis phoneme. So, for /t, d/ the only relevant distinctive features are: voiceless, fortis vs. voiced lenis. Other features are irrelevant.

A phonemic system presupposes a system of oppositions. But opposition is not exclusively a phonological concept, it is a logical one, and the role it plays in phonology is strongly reminiscent of its role in psychology. It is impossible to study phonological oppositions (of which phonemes are only the terms) without analyzing the concept of the opposition from the point of view of psychology and logic (Trubetzkoy 2001[1936]:15).

Types of opposition. Depending on the number of relevant distinctive features oppositions can be: a) single, b) double; c) multiple. Originally (in 1929) it was only correlative, e.g. p/b; t/d or i/i: Π/ L (i.e., presence vs. absence). All others are disjunctive. In 1936/1939 opposition classification was elaborated to cover: their relation to the overall system Рbilateral or multilateral; isolated or proportional. The relation between the members of the opposition can be privative, gradual or equipollent. Their distinctive validity may be constant or suspendable.

The functional notion of opposition is that of contrast: a phonological opposition exists between two sound sequences when the substitution of one for the other results in a different meaning. Oppositions can be classified along several simultaneous dimensions:

• isolated (the same combination does not serve to distinguish any other pair) e.g. /d/ and /m/;

• proportional (recurrent) e.g. /p/ and /b/ (cf. /t/ and /d/, /s/ and /z/ etc.);

• bilateral (exactly two phonemes are distinguished minimally on a given dimension), e.g. English voiced and unvoiced, since there is no third value;

• multilateral (the same property distinguishes more than two phonemes along the same dimension) e.g. /p/, /t/, /k/ along place of articulation;

• privative (one phoneme contains a property which is lacking in the other) e.g. phonemes with and without an added nasal resonance, vowels with and without rounding;

• equipollent (when two phonemes differ in that they contain different properties) e.g. front and back vowels;

• gradual (phonemes possess a given property to varying degrees) e.g. mid and high vowels.