Phrase structure grammar
Encyclopedia
The term phrase structure grammar was originally introduced by Noam Chomsky
as the term for grammar
s as defined by phrase structure rules
, i.e. rewrite rule
s of the type studied previously by Emil Post and Axel Thue
(see Post canonical system
s). Some authors, however, reserve the term for more restricted grammars in the Chomsky hierarchy
: context-sensitive grammar
s, or context-free grammar
s. In a broader sense, phrase structure grammars are also known as constituency grammars. The defining trait of phrase structure grammars is thus their adherence to the constituency relation, as opposed to the dependency relation of dependency grammars
.
, phrase structure grammars are all those grammars that are based on the constituency relation, as opposed to the dependency relation associated with dependency grammars, hence phrase structure grammars are also known as constituency grammars. Any of several related theories for the parsing of natural language
qualify as constituency grammars, and most of them were developed from Chomsky's work, including
Further grammar frameworks also qualify as constituency grammars, although they may not think of the themselves as having spawned from Chomsky's work, e.g.
The fundamental trait that these frameworks all share is that they view sentence structure in terms of the constituency relation. The constituency relation derives from the subject
-predicate
division of Latin and Greek grammars that is based on term logic
and reaches back to Aristotle
in antiquity. Basic clause
structure is understood in terms of a the binary division of the clause into subject (noun phrase
NP) and predicate (verb phrase
VP).
The binary division of the clause results in a one-to-one-or-more correspondence. For each element in a clause, there are one or more nodes in the tree structure that one assumes for that element. A two word sentence such as Luke laughed necessarily implies three (or more) nodes in the syntactic structure: one for the noun Luke (subject NP), one for the verb laughed (predicate VP), and one for the entirety Luke laughed (sentence S). The constituency grammars listed above all view sentence structure in terms of this one-to-one-or-more correspondence.
, a competing understanding of the logic of sentences had arisen. Frege rejected the binary division of the sentence and replaced it with an understanding of sentence logic in terms of predicates and their arguments. On this alternative conception of sentence logic, the binary division of the clause into subject and predicate was not possible. It therefore opened the door to the dependency relation (although the dependency relation had also existed in a less obvious form in traditional grammars long before Frege). The dependency relation was first acknowledged concretely and developed as the basis for a comprehensive theory of syntax and grammar by Lucien Tesnière
in his posthumously published work Éléments de syntaxe structurale (Elements of Structural Syntax).
The dependency relation is a one-to-one correspondence: for every element (word or morph) in a sentence, there is just one node in the syntactic structure. The distinction is thus a graph-theoretical
distinction. The dependency relation restricts the number of nodes in the syntactic structure of a sentence to the exact number of syntactic units (usually words) that that sentence contains. Thus the two word sentence Luke laughed implies just two syntactic nodes, one for Luke and one for laughed. Some prominent dependency grammars are listed here:
Since these grammars are all based on the dependency relation, they are by definition NOT phrase structure grammars.
Noam Chomsky
Avram Noam Chomsky is an American linguist, philosopher, cognitive scientist, and activist. He is an Institute Professor and Professor in the Department of Linguistics & Philosophy at MIT, where he has worked for over 50 years. Chomsky has been described as the "father of modern linguistics" and...
as the term for grammar
Formal grammar
A formal grammar is a set of formation rules for strings in a formal language. The rules describe how to form strings from the language's alphabet that are valid according to the language's syntax...
s as defined by phrase structure rules
Phrase structure rules
Phrase-structure rules are a way to describe a given language's syntax. They are used to break down a natural language sentence into its constituent parts namely phrasal categories and lexical categories...
, i.e. rewrite rule
Rewrite rule
In linguistics, a rewrite rule for natural language in generative grammar is a rule of the form A → X where A is a syntactic category label, such as noun phrase or sentence, and X is a sequence of such labels and/or morphemes, expressing the fact that A can be replaced by X in generating the...
s of the type studied previously by Emil Post and Axel Thue
Axel Thue
Axel Thue was a Norwegian mathematician, known for highly original work in diophantine approximation, and combinatorics....
(see Post canonical system
Post canonical system
A Post canonical system, as created by Emil Post, is a string-manipulation system that starts with finitely-many strings and repeatedly transforms them by applying a finite set of specified rules of a certain form, thus generating a formal language...
s). Some authors, however, reserve the term for more restricted grammars in the Chomsky hierarchy
Chomsky hierarchy
Within the field of computer science, specifically in the area of formal languages, the Chomsky hierarchy is a containment hierarchy of classes of formal grammars....
: context-sensitive grammar
Context-sensitive grammar
A context-sensitive grammar is a formal grammar in which the left-hand sides and right-hand sides of any production rules may be surrounded by a context of terminal and nonterminal symbols...
s, or context-free grammar
Context-free grammar
In formal language theory, a context-free grammar is a formal grammar in which every production rule is of the formwhere V is a single nonterminal symbol, and w is a string of terminals and/or nonterminals ....
s. In a broader sense, phrase structure grammars are also known as constituency grammars. The defining trait of phrase structure grammars is thus their adherence to the constituency relation, as opposed to the dependency relation of dependency grammars
Dependency grammar
Dependency grammar is a class of modern syntactic theories that are all based on the dependency relation and that can be traced back primarily to the work of Lucien Tesnière. Dependency grammars are distinct from phrase structure grammars , since they lack phrasal nodes. Structure is determined by...
.
Constituency relation
In linguisticsLinguistics
Linguistics is the scientific study of human language. Linguistics can be broadly broken into three categories or subfields of study: language form, language meaning, and language in context....
, phrase structure grammars are all those grammars that are based on the constituency relation, as opposed to the dependency relation associated with dependency grammars, hence phrase structure grammars are also known as constituency grammars. Any of several related theories for the parsing of natural language
Natural language
In the philosophy of language, a natural language is any language which arises in an unpremeditated fashion as the result of the innate facility for language possessed by the human intellect. A natural language is typically used for communication, and may be spoken, signed, or written...
qualify as constituency grammars, and most of them were developed from Chomsky's work, including
- Government and Binding TheoryGovernment and binding theoryGovernment and binding is a theory of syntax and a phrase structure grammar in the tradition of transformational grammar developed principally by Noam Chomsky in the 1980s...
, - Generalized Phrase Structure Grammar,
- Head-Driven Phrase Structure GrammarHead-driven phrase structure grammarHead-driven phrase structure grammar is a highly lexicalized, non-derivational generative grammar theory developed by Carl Pollard and Ivan Sag. It is the immediate successor to generalized phrase structure grammar. HPSG draws from other fields such as computer science and uses Ferdinand de...
, - Lexical Functional GrammarLexical functional grammarLexical functional grammar is a grammar framework in theoretical linguistics, a variety of generative grammar. It is a type of phrase structure grammar, as opposed to a dependency grammar. The development of the theory was initiated by Joan Bresnan and Ronald Kaplan in the 1970s, in reaction to...
, and - The Minimalist Program.
Further grammar frameworks also qualify as constituency grammars, although they may not think of the themselves as having spawned from Chomsky's work, e.g.
- Categorial GrammarCategorial grammarCategorial grammar is a term used for a family of formalisms in natural language syntax motivated by the principle of compositionality and organized according to the view that syntactic constituents should generally combine as functions or according to a function-argument relationship...
The fundamental trait that these frameworks all share is that they view sentence structure in terms of the constituency relation. The constituency relation derives from the subject
Subject (grammar)
The subject is one of the two main constituents of a clause, according to a tradition that can be tracked back to Aristotle and that is associated with phrase structure grammars; the other constituent is the predicate. According to another tradition, i.e...
-predicate
Predicate (grammar)
There are two competing notions of the predicate in theories of grammar. Traditional grammar tends to view a predicate as one of two main parts of a sentence, the other being the subject, which the predicate modifies. The other understanding of predicates is inspired from work in predicate calculus...
division of Latin and Greek grammars that is based on term logic
Term logic
In philosophy, term logic, also known as traditional logic or aristotelian logic, is a loose name for the way of doing logic that began with Aristotle and that was dominant until the advent of modern predicate logic in the late nineteenth century...
and reaches back to Aristotle
Aristotle
Aristotle was a Greek philosopher and polymath, a student of Plato and teacher of Alexander the Great. His writings cover many subjects, including physics, metaphysics, poetry, theater, music, logic, rhetoric, linguistics, politics, government, ethics, biology, and zoology...
in antiquity. Basic clause
Clause
In grammar, a clause is the smallest grammatical unit that can express a complete proposition. In some languages it may be a pair or group of words that consists of a subject and a predicate, although in other languages in certain clauses the subject may not appear explicitly as a noun phrase,...
structure is understood in terms of a the binary division of the clause into subject (noun phrase
Noun phrase
In grammar, a noun phrase, nominal phrase, or nominal group is a phrase based on a noun, pronoun, or other noun-like word optionally accompanied by modifiers such as adjectives....
NP) and predicate (verb phrase
Verb phrase
In linguistics, a verb phrase or VP is a syntactic unit composed of at least one verb and the dependents of that verb. One can distinguish between two types of VPs, finite VPs and non-finite VPs . While phrase structure grammars acknowledge both, dependency grammars reject the existence of a...
VP).
The binary division of the clause results in a one-to-one-or-more correspondence. For each element in a clause, there are one or more nodes in the tree structure that one assumes for that element. A two word sentence such as Luke laughed necessarily implies three (or more) nodes in the syntactic structure: one for the noun Luke (subject NP), one for the verb laughed (predicate VP), and one for the entirety Luke laughed (sentence S). The constituency grammars listed above all view sentence structure in terms of this one-to-one-or-more correspondence.
Dependency relation
By the time of Gottlob FregeGottlob Frege
Friedrich Ludwig Gottlob Frege was a German mathematician, logician and philosopher. He is considered to be one of the founders of modern logic, and made major contributions to the foundations of mathematics. He is generally considered to be the father of analytic philosophy, for his writings on...
, a competing understanding of the logic of sentences had arisen. Frege rejected the binary division of the sentence and replaced it with an understanding of sentence logic in terms of predicates and their arguments. On this alternative conception of sentence logic, the binary division of the clause into subject and predicate was not possible. It therefore opened the door to the dependency relation (although the dependency relation had also existed in a less obvious form in traditional grammars long before Frege). The dependency relation was first acknowledged concretely and developed as the basis for a comprehensive theory of syntax and grammar by Lucien Tesnière
Lucien Tesnière
Lucien Tesnière was one of the most prominent and influential French linguists.Tesnière was born in Mont-Saint-Aignan on May 13, 1893...
in his posthumously published work Éléments de syntaxe structurale (Elements of Structural Syntax).
The dependency relation is a one-to-one correspondence: for every element (word or morph) in a sentence, there is just one node in the syntactic structure. The distinction is thus a graph-theoretical
Graph theory
In mathematics and computer science, graph theory is the study of graphs, mathematical structures used to model pairwise relations between objects from a certain collection. A "graph" in this context refers to a collection of vertices or 'nodes' and a collection of edges that connect pairs of...
distinction. The dependency relation restricts the number of nodes in the syntactic structure of a sentence to the exact number of syntactic units (usually words) that that sentence contains. Thus the two word sentence Luke laughed implies just two syntactic nodes, one for Luke and one for laughed. Some prominent dependency grammars are listed here:
- Algebraic SyntaxAlgebraic syntaxRecursive categorical syntax, also sometimes called algebraic syntax, is an algebraic theory of syntax developed by Michael Brame as an alternative to transformational-generative grammar.-References:...
- Operator GrammarOperator GrammarOperator Grammar is a mathematical theory of human language that explains how language carries information. This theory is the culmination of the life work of Zellig Harris, with major publications toward the end of the last century...
- Functional Generative DescriptionFunctional Generative DescriptionFunctional Generative Description is a linguistic framework developed at Charles University in Prague since the 1960s by a team led by Petr Sgall...
- Algebraic SyntaxAlgebraic syntaxRecursive categorical syntax, also sometimes called algebraic syntax, is an algebraic theory of syntax developed by Michael Brame as an alternative to transformational-generative grammar.-References:...
- Lexicase
- Meaning-Text TheoryMeaning-Text TheoryMeaning–text theory is a theoretical linguistic framework, first put forward in Moscow by Aleksandr Žolkovskij and Igor Mel’čuk, for the construction of models of natural language...
- Word GrammarWord grammarWord grammar has been developed by Richard Hudson since the 1980s. It started as a model of syntax, whose most distinctive characteristic is its use of dependency grammar, an approach to syntax in which the sentence's structure is almost entirely contained in the information about individual words,...
Since these grammars are all based on the dependency relation, they are by definition NOT phrase structure grammars.
Non-descript grammars
Other grammars generally avoid attempts to group syntactic units into clusters in a manner that would allow classification in terms of the constituency vs. dependency distinction. In this respect, the following grammar frameworks do not come down solidly on either side of the dividing line:- Construction grammarConstruction grammarThe term construction grammar covers a family of theories, or models, of grammar that are based on the idea that the primary unit of grammar is the grammatical construction rather than the atomic syntactic unit and the rule that combines atomic units, and that the grammar of a language is made up...
- Cognitive grammarCognitive grammarCognitive grammar is a cognitive approach to language developed by Ronald Langacker, which considers the basic units of language to be symbols or conventional pairings of a semantic structure with a phonological label. Grammar consists of constraints on how these units can be combined to generate...