Inquisitive semantics is a semantic framework that is based on a new formal notion of meaning, capturing both informative and inquisitive content. This enriched notion of meaning is intended to provide a new foundation for the analysis of information exchange through communication.
In inquisitive semantics, a sentence is taken to express a proposal to update the common ground of a conversation in one or more ways. If a sentence proposes two or more alternative updates it is inquisitive, inviting a response from other participants that establishes at least one of the alternative updates.
Formally, the proposition expressed by a sentence is a set of possibilities. Each of these possibilities in turn is a set of possible worlds, embodying a potential update of the common ground. Purely informative sentences express a proposition containing just one alternative possibility. Inquisitive sentences express a proposition containing two or more alternative possibilities.
The way in which inquisitive semantics enriches the notion of meaning changes our perspective on logic as well. Besides the classical notion of entailment, the semantics also gives rise to a new notion of inquisitive entailment, and to new logical notions of relatedness, which determine whether one sentence compliantly addresses the proposal expressed by another.
The way in which inquisitive semantics enriches the notion of meaning also changes our perspective on pragmatics. The main objective of Gricean pragmatics is to explain aspects of interpretation that are not directly dictated by semantic content, in terms of general features of rational human behavior. Since inquisitive semantics changes the notion of semantic content, pragmatics changes with it. Gricean pragmatics consists exclusively of speaker-oriented rules for providing information. Inquisitive pragmatics has the same basic objective, but is more general: it is both speaker- and hearer-oriented, and specifies rules for exchanging information rather than just providing information. This makes it possible to derive a wider range of implicatures, in particular ones that arise from inquisitiveness.