According to inferential expressivism (Incurvati&Schloeder 2024), the meaning of a term is given by the inferential relations that an attitude expression toward a sentence containing the term bears to other attitude expressions in virtue of the fact that the sentence contains that term. Bilateralism illustrates this idea by explaining the meaning of negation in terms of the speech acts of assertion and rejection, and naturally extends to multilateralism once we consider further speech acts beyond these two, such as weak rejection and weak assertion (Incurvati&Schloeder 2017, 2019).

In this talk, I apply the multilateralist methodology to develop an inferential–expressivist account of the meaning of interrogative sentences. I present a system that captures the inferential relations between the question-directed speech acts of asking, answering, and rejecting a question, and the statement-directed acts of assertion and weak rejection. The resulting calculus provides a unified inferential–expressivist treatment of declarative and interrogative sentences and is sound and complete with respect to a system of KD45 inquisitive modal logic. I conclude by discussing possible extensions of the framework.