Why Subjacency Duplexes Are Passed Over In Functional Grammar Descriptions

Martin & Doran (2023: 38):

As we can see, subjacency duplex analysis adds layers of structure to tables (or trees). This is inevitable if we strictly follow the principle that classes are realised by grammatical functions (such as α β# or #β α) and functions in turn by classes as we move from higher ranks to lower ones (shifting perspective back and forth between syntagm and structure as we go). This does present a problem, however, if we want to use our tables (or trees) to reflect grammatical complexity (Halliday 2008). Unlike serial complexing (the resource expanding the meaning potential of spoken language) or embedding (the resource expanding the meaning potential of written language), layers of subjacency structure do not reflect systemic choices of their own — they are part of the realisation of choices in other implicating systems. Put another way, they don’t add an extra layer of meaning to the structures with which they are involved. This is possibly why they are passed over in many functional grammar descriptions, especially where the goal is text analysis (following, for example, Halliday 1985 and its subsequent 1994 edition) rather than a comprehensive description.

Blogger Comments:

[1] This is misleading. In SFL Theory, structures realise systems. In the authors' own model, subjacency duplexes are said to be logical structures that realise non-recursive systems, so this claim is even inconsistent with their own model. 

Importantly, the problem that the authors are trying to conceal here is that it is not possible to specify the entry condition for a system that specifies a subjacency duplex. This is because the entry conditions for grammatical systems are units on the rank scale, and, unlike all other complexes, a subjacency duplex is not the expansion of a rank unit, since a subjacency is not a rank unit.

[2] To be clear, if subjacency duplexes do not "add an extra layer of meaning", they do not serve any function, and so do not add any explanatory potential. In fact, as previous posts have demonstrated, a subjacency duplex analysis provides less explanatory potential than the original theory that the authors simply misunderstand.

[3] This is very misleading indeed. On the one hand, it sets up a false dichotomy: text analysis vs comprehensive description — one does not exclude the other — and on the other hand, it falsely claims that Halliday (1985; 1994) are not comprehensive descriptions.

To be clear, the reason why subjacency duplexes are "passed over" in all functional grammar descriptions not carried out by Martin and his former students, is that they only arise from misunderstandings of theory. These misunderstandings include taking the view from below, instead of the view from above, misunderstanding at which rank logical structures are located, not understanding recursive systems, not understanding iterative structures, mistaking adpositions for structure markers, and so on.