Obituary: Stephen Edelston Toulmin

Abstract

Stephen Edelston Toulmin, who died on December 4, 2009, at the age of 87, was a seminal figure in the post-war flowering of the study of argumentation. His book The Uses of Argument (Cambridge, 1958; updated edition, 2003) introduced a new model for the layout of arguments. In place of the static monological Aristotelian categorical syllogism, with its three components of major premiss, minor premiss and conclusion, Toulmin proposed a dynamic dialectical model whose components were conceived as responses to a series of questions posed by someone challenging someone else to justify a claim C. What do you have to go on? The answer would be one’s data D, termed grounds in his later co-authored textbook (Stephen Toulmin, Richard Rieke and Allan Janik, An Introduction to Reasoning [Macmillan, 1979; second edition 1984]). How do you get there (from your data to your claim)? The answer would be one’s warrant W, which in its most explicit form would be a permissive rule of inference: Data such as D entitle one to draw conclusions, or make claims, such as C. What degree of force does your warrant confer on your conclusion? The answer would be a modal qualifier Q, such as ‘‘necessarily’’, ‘‘probably’’ or ‘‘presumably’’. With a qualifier other than ‘‘necessarily’’, under what conditions would the authority of your warrant have to be set aside? The answer would be a set of conditions of exception or rebuttal R. What justifies your warrant? The answer would be backing B, which Toulmin argued was specific to the field to which the claim belonged. Toulmin’s fellow philosophers did not take up his model. Indeed, reviews of his book in philosophy journals were uniformly hostile, and to this day I know of no textbook in logic or critical thinking written by a philosopher that uses his model. But the model proved apt for the field of speech communication in the United States, a discipline that had emerged from the coaching of college debaters. The ‘‘Toulmin model’’ is an obligatory component of textbooks in argumentation in that