My research in ancient philosophy is informed by and focused on a hard problem in the history of logic and science: how did the theory of deduction emerge out of reflection on the practice of dialectical argumentation? My approach to this problem concerns the relationship between ancient practices of deduction and theories of dialectic and demonstration in Aristotle, but also the reception of those theories by authors who no longer had these practices in view. The problem is a hard one for several reasons. Perhaps the most important piece of textual evidence, Aristotle’s Topics, is a difficult book to understand. The theories of deduction leave much information about the practices sousentendu, as these theories were not meant for us. And getting to the historical background of dialectical practices in ancient philosophy is complicated by the fact that Aristotle’s “concept of dialectic” would develop a career of its own after the linguistic turn in analytic philosophy. It is also difficult because the disciplinary boundaries of philosophy, Classics, and history of science converge on it, making it a problem at the intersection of fields which are not always in close communication.
I approach this problem from the perspective of the Topics in my forthcoming book, Aristotle’s Theory of Dialectical Argumentation. I argue that in the Topics Aristotle develops a semantic framework for theorizing deduction and argumentative persuasion under conditions of acceptability (and often: semantic opacity). I identify three main parts of the theory: a basis theory of deduction, a theory of acceptability, and a theory which organizes and classifies the relevant semantic contexts of dialectic as practiced: the predicables and the τόποι. My goal in the book is to show how these three parts of the theory of dialectic may be distinguished. With this result we may better understand how certain aspects of the theory of dialectical argumentation would go on to be influential and important for Aristotle’s philosophy and science even though Aristotle rejects dialectical arguments and procedures in scientific contexts.
Interpreting Aristotle's theory of dialectical argumentation raises issues concerning the epistemology of argumentation which, from a systematic standpoint, are as relevant as ever. In a second project, which I am pursuing with Jean H.M. Wagemans (Universiteit van Amsterdam), I take an Aristotelian approach to contemporary epistemological issues in argumentation. Our book, conceived for a wide audience and for use in the logic and argumentation curriculum, is entitled Argumentation in the Wild as is under contract with MIT Press. We giving our manuscript a first test with an audience of lively and critical students at Universität Heidelberg in the summer term of 2021.