The game of Inquiry: the interrogative approach to inquiry and belief revision theory

I. Levi has advocated a decision-theoretic account of belief revision. We argue that the game-theoretic framework of Interrogative Inquiry Games, proposed by J. Hintikka, can extend and clarify this account. We show that some strategic use of the game rules (or ‘policies’) generate Expansions, Contractions and Revisions, and we give representation results. We then extend the framework to represent explicitly (multiple) sources of answers, and apply it to discuss the Recovery Postulate. We conclude with some remarks about the potential extensions of interrogative games, with respect to some issues in the theory of belief change.