Abstract

Toulmin is famously seen as the progenitor of informal logic and the related theory of argument and is first among many who seek to move the study of argument away from its roots in formal, especially mathematical, logic. Toulmin’s efforts, however, have been substantively criticized by Harvey Siegel, among others, for failing to offer the sort of foundation that, according to Siegel, even Toulmin sees to be required lest the theory of inquiry fall to impotent relativism. What I will attempt to indicate in this paper is, that although Toulmin is correct in rejecting mathematical logic as standardly construed as an adequate theory of argument, and logical empiricist constructions as an adequate basis for the philosophical understanding of science, there is a significant role for metamathematics in the new logic. In particular, I will show how a formal model based on mature physical science rather than arithmetic furnishes crucial support to Toulmin, furnishing philosophical metaphors that afford the foundational support required for normativity and the clarification of key logical concepts required for a robust normative theory of argument in the context of inquiry.