A person-centric view of multimodal language in context

As a theory of language, Systemic Functional Linguistics (SFL) is strongly orientated to the interpersonal aspects of language interaction, at times to the exclusion or minimization of the intrapersonal perspective. This over focus on one perspective can cause a skew in the framework and depending on the types of questions we are addressing in our research there may be a need to include neurological/psychological details about language processing as well as rich demographics and other person specific profiles. When this is the case, it requires an explicit model for the inclusion of intrapersonal information.
While SFL undeniably has a social focus on language, it would be unreasonable to claim that it completely ignores the individual. Rather, it is more the case that, historically, the individual perspective was assumed to be a problem for someone else, or at least that it was unproblematic to include information about the individual if needed. Indeed, we see that Halliday and Firth before him both looked at the individual. Halliday (1978) models the centrality of language and socialization in the movement from organism to person and Firth was very interested in language and personality (Firth 1950).
So, while a social view of language is extremely valuable and one of the features that makes SFL such an appliable theory, if we only focus on the social, we risk losing sight of the relationship of language to the individual. The social focus is not in and of itself problematic but if we want to address questions that sit at the intersection of SFL, cognitive science, semiotics, and AI, then we need a framework that includes cognitive processes and profiles of the individual. Such a framework would let us shift, as needed, between the social and the personal perspectives.
The need for such a dual perspective becomes very apparent with any experimental and clinical work where the individual is in focus or in educational work where the individual is set against the backdrop of the group. Any question that looks at both language as product and language as process will need to model the individual to some extent. Ideally it should be possible to move fluidly between product and process, social and personal, and to easily take an inter and intra-personal perspective.
In this chapter I outline the model that we use to apply SFL to problems in the field of artificial intelligence (AI). Although we have developed this person-centric model for applications in human-centric AI, it is also useful for experimental and clinical work that needs to centre the individual with respect to language. This model paves the way for bringing the individual fully into the SFL framework.