Production (computer science)A production or production rule in computer science is a rewrite rule specifying a symbol substitution that can be recursively performed to generate new symbol sequences. A finite set of productions is the main component in the specification of a formal grammar (specifically a generative grammar). The other components are a finite set of nonterminal symbols, a finite set (known as an alphabet) of terminal symbols that is disjoint from and a distinguished symbol that is the start symbol.
Syntactic StructuresSyntactic Structures is an important work in linguistics by American linguist Noam Chomsky, originally published in 1957. A short monograph of about a hundred pages, it is recognized as one of the most significant and influential linguistic studies of the 20th century. It contains the now-famous sentence "Colorless green ideas sleep furiously", which Chomsky offered as an example of a grammatically correct sentence that has no discernible meaning, thus arguing for the independence of syntax (the study of sentence structures) from semantics (the study of meaning).
Linguistic competenceIn linguistics, linguistic competence is the system of unconscious knowledge that one knows when they know a language. It is distinguished from linguistic performance, which includes all other factors that allow one to use one's language in practice. In approaches to linguistics which adopt this distinction, competence would normally be considered responsible for the fact that "I like ice cream" is a possible sentence of English, the particular proposition that it denotes, and the particular sequence of phones that it consists of.
Poverty of the stimulusPoverty of the stimulus (POS) is the controversial argument from linguistics that children are not exposed to rich enough data within their linguistic environments to acquire every feature of their language. This is considered evidence contrary to the empiricist idea that language is learned solely through experience. The claim is that the sentences children hear while learning a language do not contain the information needed to develop a thorough understanding of the grammar of the language.
Generalized phrase structure grammarGeneralized phrase structure grammar (GPSG) is a framework for describing the syntax and semantics of natural languages. It is a type of constraint-based phrase structure grammar. Constraint based grammars are based around defining certain syntactic processes as ungrammatical for a given language and assuming everything not thus dismissed is grammatical within that language. Phrase structure grammars base their framework on constituency relationships, seeing the words in a sentence as ranked, with some words dominating the others.
C-commandIn generative grammar and related frameworks, a node in a parse tree c-commands its sister node and all of its sister's descendants. In these frameworks, c-command plays a central role in defining and constraining operations such as syntactic movement, binding, and scope. Tanya Reinhart introduced c-command in 1976 as a key component of her theory of anaphora. The term is short for "constituent command". Common terms to represent the relationships between nodes are below (refer to the tree on the right): M is a parent or mother to A and B.
Generative semanticsGenerative semantics was a research program in theoretical linguistics which held that syntactic structures are computed on the basis of meanings rather than the other way around. Generative semantics developed out of transformational generative grammar in the mid-1960s, but stood in opposition to it. The period in which the two research programs coexisted was marked by intense and often personal clashes now known as the linguistics wars.
Tree-adjoining grammarTree-adjoining grammar (TAG) is a grammar formalism defined by Aravind Joshi. Tree-adjoining grammars are somewhat similar to context-free grammars, but the elementary unit of rewriting is the tree rather than the symbol. Whereas context-free grammars have rules for rewriting symbols as strings of other symbols, tree-adjoining grammars have rules for rewriting the nodes of trees as other trees (see tree (graph theory) and tree (data structure)).
Linguistics warsThe linguistics wars were a protracted academic dispute inside American theoretical linguistics that took place mostly in the 1960s and 1970s, stemming from an intellectual falling out between Noam Chomsky and some of his early colleagues and doctoral students. The debate began in 1967, when linguists Paul Postal, "Haj" Ross, George Lakoff, and James McCawley—self-dubbed the "Four Horsemen of the Apocalypse" (in reference to the Book of Revelation)—proposed an approach to the relationship between syntax and semantics, which treated deep structures as meanings rather than syntactic objects.
Diachrony and synchronySynchrony and diachrony are two complementary viewpoints in linguistic analysis. A synchronic approach (from συν- "together" and χρόνος "time") considers a language at a moment in time without taking its history into account. Synchronic linguistics aims at describing a language at a specific point of time, often the present. In contrast, a diachronic (from δια- "through" and χρόνος "time") approach, as in historical linguistics, considers the development and evolution of a language through history.
