Editing Systemic functional grammar (section)

==Relation to other branches of grammar==
Halliday's theory sets out to explain how spoken and written texts construe meanings and how the resources of language are organised in open systems and functionally bound to meanings. It is a [[theory of language]] in use, creating systematic relations between choices and forms within the less abstract strata of grammar and phonology, on the one hand, and more abstract strata such as context of situation and context of culture on the other. It is a radically different theory of language from others which explore less abstract strata as autonomous systems, the most notable being [[Noam Chomsky]]'s. Since the principal aim of systemic functional grammar is to represent the grammatical system as a resource for making meaning, it addresses different concerns. For example, it does not try to address Chomsky's thesis that there is a "finite rule system which generates all and only the grammatical sentences in a language".{{Citation needed|date=June 2009}} Halliday's theory encourages a more open approach to the definition of language as a resource; rather than focus on grammaticality as such, a systemic functional grammatical treatment focuses instead on the relative frequencies of choices made in uses of language and assumes that these relative frequencies reflect the probability that particular paths through the available resources will be chosen rather than others. Thus, SFG does not describe language as a [[finite rule system]], but rather as a system, realised by instantiations, that is continuously expanded by the very instantiations that realise it and that is continuously reproduced and recreated with use.

Another way to understand the difference in concerns between systemic functional grammar and most variants of generative grammar is through Chomsky's claim that "linguistics is a sub-branch of [[psychology]]". Halliday investigates linguistics more as a sub-branch of ''[[sociology]]''. SFG therefore pays much more attention to [[pragmatics]] and discourse [[semantics]] than is traditionally the case in [[Formal grammar|formalism]].

The orientation of systemic functional grammar has served to encourage several further grammatical accounts that deal with some perceived weaknesses of the theory and similarly orient to issues not seen to be addressed in more structural accounts. Examples include the model of [[Richard Hudson (linguist)|Richard Hudson]] called ''[[word grammar]]''<!--Needs to distinguish traditional word-class grammar from SFG, too-->, and [[William B. McGregor]]'s ''Semiotic Grammar'' which revises the organization of the metafunctions.<ref>{{cite book | last=McGregor | first=William B. | title=Semiotic grammar | publisher=Clarendon Press | publication-place=Oxford | date=1997 | isbn=0-19-823688-3 | oclc=36364197 | author-link = William B. McGregor}}</ref>