entailment; families of sets; logic of questions.

This paper examines critically the reconstruction of the ‘Sherlock Holmes sense of deduction’ proposed jointly by M.B. Hintikka and J. Hintikka in the 1980s, and its successor, the interrogative model of inquiry developed by J. Hintikka and his collaborators in the 1990s. The Hintikkas’ model explicitly used game theory in order to formalize a naturalistic approach to inquiry, but the imi abandoned both the game-theoretic formalism, and the naturalistic approach. It is argued that the latter better supports the claim that (...) the imi provides a ‘logic of discovery’, and safeguards its empirical adequacy. Technical changes necessary to this interpretation are presented, and examples are discussed, both formal and informal, that are better analyzed when these changes are in place. The informal examples are borrowed from Conan Doyle’s The Case of Silver Blaze, a favorite of M.B. and J. Hintikka. (shrink)