Semantics (disambiguation): Difference between revisions

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Theoretical linguistics is that branch of linguistics that is most concerned with developing models of linguistic knowledge. Part of this endeavor involves the search for and explanation of linguistic universals, that is, properties all languages have in common. The fields that are generally considered the core of theoretical linguistics are syntax, phonology, morphology, and semantics. Phonology is often informed by phonetics, which like psycholinguistics and sociolinguistics is often excluded from the purview of theoretical linguistics.

Phonology

Phonology is the branch of theoretical linguistics concerned with the production and comprehension of speech sounds in language.

Morphology

Morphology is the study of word structure. For example in the sentences The dog runs and The dogs run, the wordforms runs and dogs have an affix -s added, distinguishing them from the bare forms dog and run. Adding this suffix to a nominal stem gives plural forms, adding it to verbal stems restricts the subject to third person singular. Some morphological theories operate with two distinct suffixes -s, called allomorphs of the morphemes Plural and Third person singular, respectively. Languages differ wrt. to their morphological structure. Along one axis, we may distinguish analytic languages, with few or no suffixes or other morphological processes from synthetic languages with many suffixes. Along another axis, we may distinguish agglutinative languages, where suffixes express one grammatical property each, and are added neatly one after another, from fusional languages, with non-concatenative morphological processes (infixation, Umlaut, Ablaut, etc.) and/or with less clear-cut suffix boundaries.

Syntax

Syntax is the study of language structure and word order. It is concerned with the relationship between units at the level of morphology. Syntax seeks to delineate exactly those sentences which make up a given language, by using formal means. Syntax seeks to describe formally exactly how structural relations between elements (lexical items/words and operators) in a sentence contribute to its interpretation. Syntax uses principles of formal logic and Set Theory to formalise and represent accurately the hierarchical relationship between elements in a sentence. Thus, in active declaritive sentences in English the subject is followed by the main verb which in turn is followed by the object (SVO). This order of elements is crucial to its correct interpretation and it is exactly this which syntacticians try to capture. They argue that there must be such a formal computational component contained within the language faculty of normal speakers of a language and seek to describe it. Abstract syntax trees are the primary means of describing hierarchies in sentences.

Semantics

Semantics is the study of meaning in words and sentences. There are a number of approaches to semantics, but one approach, pioneered by Richard Montague and known as model-theoretic semantcs (or simply Montague semantics) is based on the idea of interpretation. An interpretation is a mapping from the domain of sentences to a formal structure known as a model. Models include relationships and attributes that may be defined in set-theoretic terms (e.g., older than, inanimate, owner of, etc.) for a property to be semantically interesting, it must hold in all interpretations (or all interpretations satisfying a suitable sent of restrictions). This ensures that they do not reflect accidental or contingent information.

Rule to Rule Hypothesis

An important idea in the semantics of natural languages is the rule to rule hypothesis. The idea is that any phrase structure rule or, more generally, syntactic construct, will have a corresponding semantic relationship. Thus, in the sentence

John sees Sally.

the relationship between John and Sally established by the verb see must correspond to a relationship on the level of models to which the verb see is mapped.