Speaker: Shane Steinert-Threlkeld (ILLC, Amsterdam)
Date and Time: Thursday, October 12th 2017, 16:00-17:30
Venue: ILLC Seminar Room F1.15, Science Park 107.
Title: Expressivism for Epistemic Modals: Dynamics and Uniform Definability
Abstract. Expressivists about a given fragment of language argue that the primary function of an assertion of a sentence from that fragment is not to state a fact but to express some other kind of attitude of the speaker. In this talk, I will discuss expressivism for epistemic modals like ‘might’ and investigate new logical problems that arise. For example: on the standard theory of assertion, an update operation like public announcement adequately models the evolution of the common ground. What is the corresponding dynamics for an expressivist? Answering this question requires showing that a certain disjunction is definable in terms of the other connectives. I will also show that this disjunction is not uniformly definable and discuss the implications of that result.