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 generate Expansions, Contractions and Revisions, and we give representation results. We then extend the framework to represent explicitly 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. (shrink)

The standard way of representing an epistemic state in formal philosophy is in terms of a set of sentences, corresponding to the agent’s beliefs, and an ordering of those sentences, reflecting how well entrenched they are in the agent’s epistemic state. We argue that this wide-spread representational view – a view that we identify as a “Quinean dogma” – is incapable of making certain crucial distinctions. We propose, as a remedy, that any adequate representation of epistemic states must also include (...) the agent’s research agenda, i.e., the list of question that are open or closed at any given point in time. If the argument of the paper is sound, a person’s questions and practical interests, on the one hand, and her beliefs and theoretical values, on the other, are more tightly interwoven than has previously been assumed to be the case in formal epistemology. (shrink)

W. Labov's & T. Labov's findings concerning their child grammar acquisition ("Learning the Syntax of Questions" in Recent Advances in the Psychology of Language, Campbell, R. & Smith, P. Eds, New York: Plenum Press, 1978) are interpreted in terms of different semantics of why & other wh-questions. Z. Dubiel.

Questions are triggers for explicit events of ‘issue management’. We give a complete logic in dynamic-epistemic style for events of raising, refining, and resolving an issue, all in the presence of information flow through observation or communication. We explore extensions of the framework to multi-agent scenarios and long-term temporal protocols. We sketch a comparison with some alternative accounts.

In the logical, philosophical and linguistic literature, a number of theoretical frameworks have been proposed for the meaning of questions (see Ginzburg (1995), Groenendijk & Stokhof (1997) for recent overviews). I will concentrate on two general approaches that figured prominently in linguistic semantics, which I will call the proposition set approach and the structured meaning approach (sometimes called the “propositional” and the “categorial” or “functional” approach). I will show that the proposition set approach runs into three problems: It does not (...) always predict the right focus structure in answers, it is unable to distinguish between polarity (yes/no) and a certain type of alternative questions, and it does not allow to formulate an important condition for a type of multiple constituent questions. On the other hand, I will show that the main argument brought forward against the structured meaning framework, namely that it does not give us an elegant way to account for embedded questions, does not withstand closer scrutiny. In this I will take up an issue raised in von Stechow (1990), namely, that the greater expressive power of the structured meaning approach might be necessary for the proper treatment of semantic phenomena like question formation and focusation. (shrink)

This book is a study in the logic of questions (sometimes called erotetic logic). The central topics in erotetic logic have been the structure of questions and the question-answer relationship. This book doesn't neglect these problems, but much of it is focussed on other issues. The main subject is the logical analysis of certain relations between questions and the contexts of their appearance. And our aim is to elaborate the conceptual apparatus of the inferential approach to the logic of questions. (...) Questions are asked for many reasons and for different purposes. Yet, before a question is asked or posed, a questioner must arrive at it. In many cases arriving at a question resembles coming to a conclusion: there are some premises involved and some inferential thought processes take place. If we agree that a conclusion need not be "conclusive", we may say that sometimes questions can play the role of conclusions. But questions can also perform the role of premises: we often pass from some "initial" question to another question. In other words, there are inferential thought processes - we shall call them erotetic inferences - in which questions play the roles of conclusions or conclusions and premises. The inferential approach to the logic of questions focusses its attention on the analysis of erotetic inferences. This book consists of eight chapters. (shrink)

The paper is in two parts. In Part I, a semantics for embedded and query uses of interrogatives is put forward, couched within a situation semantics framework. Unlike many previous analyses,questions are not reductively analysed in terms of their answers. This enables us to provide a notion of ananswer that resolves a question which varies across contexts relative to parameters such as goals and inferential capabilities. In Part II of the paper, extensive motivation is provided for an ontology that distinguishes (...) propositions, questions, and facts, while at the same time the semantics provided captures an important commonality between questions and propositions: factsprove propositions andresolve questions. This commonality is exploited to provide an explanation for why predicates such as know carry presuppositions such as factivity and for a novel account of the behaviour of adverbially modified predicates with interrogative, declarative and fact-nominal arguments. (shrink)

Most current work in epistemology deals with the evaluation and justification of information already acquired. In this book, Jaakko Hintikka instead discusses the more important problem of how knowledge is acquired in the first place. His model of information-seeking is the old Socratic method of questioning, which has been generalized and brought up-to-date through the logical theory of questions and answers that he has developed. Hintikka also argues that philosophers' quest for a definition of knowledge is ill-conceived and that the (...) entire notion of knowledge should be replaced by the concept of information. He offers an analysis of the different meanings of the concept of information and of their interrelations. The result is a new and illuminating approach to the field of epistemology. (shrink)

Is a genuine logic of scientific discovery possible? In the essays collected here, Hintikka not only defends an affirmative answer; he also outlines such a logic. It is the logic of questions and answers. Thus inquiry in the sense of knowledge-seeking becomes inquiry in the sense of interrogation. Using this new logic, Hintikka establishes a result that will undoubtedly be considered the fundamental theorem of all epistemology, viz., the virtual identity of optimal strategies of pure discovery with optimal deductive strategies. (...) Questions to Nature, of course, must include observations and experiments. Hintikka shows, in fact, how the logic of experimental inquiry can be understood from the interrogative vantage point. Other important topics examined include induction, explanation, the incommensurability of theories, theory-ladenness of observations, and identifiability. (shrink)

The well known AGM framework for belief revision has recently been extended to include a model of the research agenda of the agent, i.e. a set of questions to which the agent wishes to find answers (Olsson & Westlund in Erkenntnis , 65 , 165–183, 2006 ). The resulting model has later come to be called interrogative belief revision . While belief revision has been studied extensively from the point of view of modal logic, so far interrogative belief revision has (...) only been dealt with in the metalanguage approach in which AGM was originally presented. In this paper, I show how to model interrogative belief revision in a modal object language using a class of operators for questions. In particular, the solution I propose will be shown to capture the notion of K-truncation , a method for agenda update in the case of expansion constructed by Olsson & Westlund. Two case studies are conducted: first, an interrogative extension of Krister Segerberg’s system DDL, and then a similar extension of Giacomo Bonanno’s modal logic for belief revision. Sound and complete axioms will be provided for both of the resulting logics. (shrink)