The anatomy of a systemic choice

Abstract : Systemic grammar is one of the major varieties of syntactic theory in modern linguistics. It was originally defined by Michael A. K. Halliday around 1960 and has since been developed extensively by him and others. Unlike transformational grammar, systemic grammar is oriented to the ways that language functions for its users. Systemic grammars have been used in several well-known language-processing programs and have been found to be very advantageous for computer generation of text. This report presents a framework for expressing how choices are made in systemic grammars. Formalizing the description of choice processes enriches descriptions of the syntax and semantics of languages, and it contributes to constructive models of language use. There are applications in education and computation. The framework represents the grammar as a combination of systemic syntatic description and explicit choice processes, called 'choice experts'. Choice experts communicate across the boundary of the grammar to its environment, exploring an external intention to communicate. The environment's answers lead to choices and thereby to creation of sentences and other units, tending to satisfy the intention to communicate. The experts' communicative framework includes an extension to the systemic notion of a function, in the direction of a more explicit semantics. Choice expert processes are presented in two notations, one informal and the other formal. The informal notation yields a grammar-guided conversation in English between the grammar and its environment, while the formal notation yields complete accounts of what the grammar produces given a particular circumstance and intent. (Author)