It is clear that language does different things in our lives. Linguists have often tried to categorise these different functions with identifiable labels so that we have a common vocabulary for talking about what language does. Halliday's three 'metafunctions' of language underlie the approach taken here, but with some slight alterations. The word 'metafunction' uses the morpheme 'meta' meaning 'higher' to refer to general functions of language. We present the version from Jeffries (2013a) which sets out the three metafunctions as follows:
Linguistic
Ideational Interpersonal
The linguistic metafunction in this system is intended to indicate all the basic structural and semantic tasks performed by the units and combination of units in a language. This would include all the information covered under Structures of Language in this toolbox and much more like it. This metafunction underlies the other two, which depend on the basics of a language to perform their functions.
The ideational metafunction covers all the ways in which we use language to represent the world in texts (whether spoken or written). See How people represent the world through language for more details and individual tools of analysis. These individual tools of analysis each focus on one of the 'textual-conceptual functions' which form the basis of Critical Stylistics (Jeffries 2010 and 2013b) and which try to capture the different ways in which a text may present the speaker's or author's view of the world.
These textual-conceptual functions help us to understand how ideology can be embedded in a text, sometimes below the level of conscious notice. This is important for persuasion and influencing the reader. It can therefore be used for good or ill in the negotiation of conflicts and disagreements and it is useful for analysts, mediators and conflict resolution professionals to be aware of such hidden ideologies.
The interpersonal metafunction of language covers all the ways in which we interact with people through language. This includes the basic mechanisms of interaction, such as turn-taking and interruption and also the ways in which we seek to achieve things by using language. These include, for example, speech acts (apologise, request etc.) and implicatures (i.e. implying). See How people interact for more on these issues.
Recommended reading
Halliday, Michael A. K. 1994. An Introduction to Functional Grammar (2nd edition). London: Edward Arnold.
Jeffries, Lesley. 2013. "Interpretation." In The Handbook of Stylistics, ed. by Paul Stockwell and Sara Whiteley. Cambridge: Cambridge University Press.
Jeffries, Lesley. 2013. "Critical Stylistics." In The Routledge Handbook of Stylistics, ed. by Michael Burke. London: Routledge.
Levinson, Stephen C. 1983. Pragmatics. Cambridge: Cambridge University Press.