KR2023Proceedings of the 20th International Conference on Principles of Knowledge Representation and ReasoningProceedings of the 20th International Conference on Principles of Knowledge Representation and Reasoning

Rhodes, Greece. September 2-8, 2023.

Edited by

ISSN: 2334-1033
ISBN: 978-1-956792-02-7

Sponsored by
Published by

Copyright © 2023 International Joint Conferences on Artificial Intelligence Organization

Fuzzy Truth, Fuzzy Support and Fuzzy Information States for Inquisitive Semantics

  1. Vít Punčochář(Institute of Philosophy, Czech Academy of Scieces)


  1. Uncertainty, vagueness, many-valued and fuzzy logics
  2. Belief revision and update, belief merging, information fusion
  3. Reasoning about knowledge, beliefs, and other mental attitudes
  4. Dealing with uncertain, incomplete or contradictory information


In logic, the meaning of a sentence is usually reduced to its truth conditions. However, this makes sense only for declarative sentences. In order to model also the meaning of questions, inquisitive semantics replaces the truth-conditional approach relating sentences to possible worlds with a support-conditional approach that relates sentences to information states. The standard framework of inquisitive semantics is based on a crisp notion of an information state, defined as a set of possible worlds, and a crisp relation of informational support. This paper introduces and studies two refinements of the standard framework. The first refinement takes into account fuzzy information states (defined as fuzzy sets of possible worlds) and the second one introduces a notion of fuzzy informational support. The main result of this paper shows that in the resulting framework that fuzzifies inquisitive semantics in two different directions we obtain an abstract and very general version of a principle known from the basic inquisitive semantics as Truth-Support Bridge.