Ralph Johnson has proposed a “two tiered” conception of argument, comprising of the illative core and the dialectical tier. This paper's two-part thesis is that (i) the dialectical tier is best understood as an epistemic requirement for argument, and (ii) once understood epistemically, the dialectical tier requirement can be defended against the leading objections.

A variety of theoretical and epistemological perspectives on the notion of argument has contributed towards the development of numerous text analysis systems in contemporary argumentation research, making the selection of an analytic model for the description and evaluation of arguments in natural language contexts a complex task for researchers. Not surprisingly, Western scholars have overwhelmingly relied on Anglo- and Euro-centric models of argumentation as normative references of argument structure and quality in a variety of research contexts, disregarding plurality of practice (...) within socio-cultural contexts. I will discuss how the findings of my own research, in which I examine the rhetorical styles of Australian and Japanese students’ academic writing in English, have led me to suggest an approach towards argument analysis that accommodates the variety of rhetorical styles found in my studies of academic writing and contributes towards a useful account of the functions and structures of academic argument in contemporary tertiary texts. (shrink)