Although debate is a richly structured and prevalent form of discourse, it has received little scholarly attention. Logicians have focused on the structure of individual arguments—how they divide into premises and conclusions, which in turn divide into various constituents. In contrast, I focus on the structure of sets of arguments, showing how arguments are themselves constituents in high-level dialectical structures. I represent debates and positions by graphs whose vertices correspond to arguments and whose edges correspond to two inter-argument relations: “dispute” (...) and “support,” respectively. On this basis I develop a theory of the structure of debate. (shrink)

In ordinary circumstances, we can assess the worth of evidence well enough without benefit of any theory; but when evidence is especially complex, ambiguous, or emotionally disturbing—as it often is in legal contexts—epistemological theory may be helpful. A legal fact-finder is asked to determine whether the proposition that the defendant is guilty, or is liable, is established to the required degree of proof by the [admissible] evidence presented; i.e., to make an epistemological appraisal. The foundherentist theory developed in Evidence and (...) Inquiry can help us understand what this means; and reveals that degrees of proof cannot be construed as mathematical probabilities: a point illustrated by comparing the advantages of a foundherentist analysis with the disadvantages of probabilistic analyses of the evidence in the Sacco and Vanzetti case (1921), and of the role of the statistical evidence in Collins (1968). (shrink)