Argumentation and Abduction in Dialogical Logic

Abstract

This chapter advocates for a reconciliation of argumentation theory and formal logic in an agent-centered theory of reasoning, that is, a theory in which inferences are studied as human activities. First, arguments in favor of a divorce between the two fields are presented. Those arguments are not so controversial. However, rather than forcing a radical separation, they urge logicians to rethink the object of their studies. Arguments cannot be analyzed as objects independent from human activity, whether it is dealt with deductive or nondeductive reasoning. The present analysis naturally takes place in the context of dialogical logic in which the proof process and the semantics are conceived in terms of argumentative games, which involve the agents, their commitments and their actions. This work focuses first on deductive reasoning and then takes abduction as a case of nondeductive reasoning. By relying on some relevant ideas of the Gabbay–Woods (GW) schema of abduction and Aliseda’s approach, a new dialogical explanation of abduction in terms of concession-problem is proposed. This notion of concession problem will be defined thereafter. With respect to the topics of the model-based sciences, the question of the specificity of the speech act by means of which a hypothesis is conjectured is set more specifically.