Dr. Brendan Larvor (University of Hertfordshire)
What philosophy of mathematical practice can teach pragma-dialectical theory about diagrams and pictures
2 November 2011

Argumentation theorists typically think of arguments as verbal exchanges. However, there is an increasing move to consider diagrams and other visual devices in argumentation. A leading figure in this movement is Leo Groarke, who uses the approach to argumentation developed by van Eeemeren and Grootendorst.
In this paper, I argue using mathematical examples that this approach fails. In fact, it excludes the very possibility of visual argumentation properly so called. I offer a diagnosis, and suggest that the approach to argument pioneered by C.S. Peirce offers a way forward that does justice to visual argumentation and satisfies the broad aims of the movement for the study of argumentation. The full paper is available at: http://herts.academia.edu/BrendanLarvor/Papers/803187