finite-state grammar (FSG)

A type of GRAMMAR discussed by Noam Chomsky in his book Syntactic Structures (1957) as an illustration of a simple GENERATIVE DEVICE. Finite-state grammars generate by working through a SENTENCE ‘from left to right’; an INITIAL ELEMENT is selected, and thereafter the possibilities of occurrence of all other elements are wholly determined by the nature of the elements preceding them. For example, in the sentence The cat saw the dog, the grammar would start by specifying the first WORD (i.e. selecting one of the set of possible first words for a sentence in English), proceed from this ‘initial state’ to specify the next word (i.e. one of the set of words which can follow the), and continue this process until the ‘final state’ of the sentence has been arrived at. Chomsky shows how this extremely simple kind of grammar is incapable of accounting for many important processes of sentence formation, as in DISCONTINUOUS CONSTRUCTIONS, e.g. The boys who saw John are going, where the grammatical relationship of boys to are cannot be handled in a finite-state grammar. Alternative grammars are discussed by Chomsky which improve on this MODEL in several respects. Finite-state grammars, also called ‘one-sided linear grammars’, ‘regular grammars’ and ‘Type-3 grammars’, generate finite-state languages (FSLs).