IntroductionIf we were to identify the beginning of the study of visual argumentation, we would have to choose 1996 as the starting point. This was the year that Leo Groarke published “Logic, art and argument” in Informal logic, and it was the year that he and David Birdsell co-edited a special double issue of Argumentation and Advocacy on visual argumentation . Among other papers, the issue included Anthony Blair’s “The possibility and actuality of visual arguments”. It was also the year (...) that Gail J. Chryslee, Sonja K. Foss and Arthur L. Ranney published their short text on “The construction of claims in visual argumentation” , stating that even though theorists may know a great deal about the process of argumentation, “virtually none of this knowledge is applicable to visual argumentation […] because of the properties that distinguish visual imagery from discursive symbols” .Texts on visual rhetoric have been written as far back as the early 1980s, .. (shrink)

Visual arguments can seem to require unique, autonomous evaluative norms, since their content seems irreducible to, and incommensurable with, that of verbal arguments. Yet, assertions of the ineffability of the visual, or of visual-verbal incommensurability, seem to preclude counting putatively irreducible visual content as functioning argumentatively. By distinguishing two notions of content, informational and argumentative, I contend that arguments differing in informational content can have equivalent argumentative content, allowing the same argumentative norms to be rightly applied in their evaluation.