9. October 2012, Logic Tea, Mathias Madsen

Abstract

As Jaakko Hintikka has repeatedly pointed out, the meaning of an assertive sentence can be described in terms of a game. If I say that "any integer can be written as the sum of two primes," I implicitly make a claim to knowledge, and this claim can be attacked and defended along certain lines, as defined by the sentence.

To some extent, everyday conversation can be viewed the same way. Utterances like "That was a stupid thing to do, wasn't it?" set up particular possibilities for strategic attack (challenging the speaker's authority or rights) and defense (defusing or worming out of accountability).

However, because classical game semantics depicts conversation as essentially polemic, it is blind to most of everyday language. I my talk, I will present a modest generalization of Hintikka's system that is more geared to deal with cooperation, uncertainty, and realistic turn-taking. I test this model by applying it to a number of "free choice" phenomena (roughly speaking, some phenomena related to the meaning of the word "any"). I will also examine its cognitive assumptions more directly.

To the extent that this model fits the bill, it suggests that the care for truth which we usually take logic to formalize in fact is a highly specialized conversation skill, with arbitrary restrictions on the number of players, their preferences, their knowledge, and their strategic wiggle room. Seeing these assumptions in perspective helps us see logic for what it is, a tool for modeling accountability in social interaction, and a sub-discipline of social psychology.

The Logic Tea homepage can be found at http://www.illc.uva.nl/logic_tea/. For more information, please contact Johannes Marti (johannes.marti at gmail.com), Sebastian Speitel (sebastian.speitel at gmail.com), or Matthijs Westera (M.Westera at uva.nl).