The SFL Method Of Sequencing Elements In A Unit

Fawcett (2010: 221):

Systemic functional linguists have explored two ways of locating elements in an appropriate sequential relationship to each other in a unit. The first — which may at first sight appear to be the simplest — is to locate each element in its 'place' by relating it to some previously located element. This approach depends crucially on the existence of what we might term an 'anchor' element in each unit, i.e., the existence of a 'pivotal' element that is always present. It was this method that Halliday used in his seminal first description of a generative SF grammar (Halliday 1969/81). Surprisingly, references to this as a method of sequencing elements in a SF grammar are still found in current descriptions by Halliday (1993: 5405) and Matthiessen (1995: 23-4).

I say "surprisingly" because, when Mann and Matthiessen were working on the large-scale computer implementation of Halliday's SF grammar in the Penman Project in the late 1970s, this approach caused problems. When faced with the additional complexities of building an [sic] large, generative grammar, they found that in practice they had to turn to the second method — to which we shall come in a moment (Matthiessen, personal communication).

Blogger Comments:

[1] To be clear, the first method of sequencing elements is Halliday's theoretical approach, whereas the second is Fawcett's method for adapting SFL Theory to the limitations of computers for the purpose of text generation.

[2] This is potentially misleading. In terms of the realisation statements that specify the sequencing of elements, what is required is the insertion of the elements that are to be sequenced. The notions of 'pivotal' and 'anchor' are irrelevant, as demonstrated by realisation rules like Finite^Subject, where neither element is 'pivotal' or an 'anchor', even in Fawcett's terms, since the 'anchor' or 'pivotal' element of the clause in the Cardiff Grammar is the 'Main Verb' (p201).)

[3] To be clear, the cited instances are as follows. Halliday (1995 [1993]: 272):

(c) 'Order' an element with respect to another, or to some defined location (e.g., order finite auxiliary before subject);

Matthiessen (1995: 23-4):

Structuring statements determine the organisation within one layer of a function structure:

(1) the presence of a grammatical function (insertion; e.g., "insert Subject," symbolised +Subject), 

(2) the relative sequence of two grammatical functions (ordering; e.g., "order Subject Finite," symbolised Subject^Finite), and  

(3) the constituency relationship between two functions (expansion; e.g., "expand Mood Subject", symbolised Mood(Subject)).

[4] The word "surprisingly" here is misleading, because it is the opposite of what is true. The need to adapt a theory of human language to the limitations of computers for text generation would not be surprising to anyone engaged in such a project, unless they were unable to distinguish between theory and its context-specific application.