Here, I focus on deviations of intent, from that expressed by the standard or ordinary use of language, in instances where abductive reasoning plays a necessary role. In such cases, speakers usually utter some “mysterious” words based on the assumed abductive capability of their interlocutors. In order to cause the desired effect in the audience, the speaker relies on the hearer’s knowledge of the relevant common dialogue framework and thus uses the utterance as an abductive trigger. For purposes of explanation, (...) I present a curious kind of fallacy: ironic fallacy. (shrink)

We argue that abduction does not work in isolation from other inference mechanisms and illustrate this through an inference scheme designed to evaluate multiple hypotheses. We use game theory to relate the abductive system to actions that produce new information. To enable evaluation of the implications of this approach we have implemented the procedures used to calculate the impact of new information in a computer model. Experiments with this model display a number of features of collective belief-revision leading to consensus-formation, (...) such as the influence of bias and prejudice. The scheme of inferential calculations invokes a Peircian concept of ‘belief’ as the propensity to choose a particular course of action. (shrink)