•  64
    The paper studies first order extensions of classical systems of modal logic (see (Chellas, 1980, part III)). We focus on the role of the Barcan formulas. It is shown that these formulas correspond to fundamental properties of neighborhood frames. The results have interesting applications in epistemic logic. In particular we suggest that the proposed models can be used in order to study monadic operators of probability (Kyburg, 1990) and likelihood (Halpern-Rabin, 1987).
  •  137
    This special issue presents a series of articles focusing on recent work in formal epistemology and formal philosophy. The articles in the latter category elaborate on the notion of context and content and their relationships. This work is not unrelated to recent developments in formal epistemology. Logical models of context, when connected with the representation of epistemic context, are clearly relevant for many issues considered by formal epistemologists. For example, the semantic framework …Read more
  • Quantified Modal Logic
    Journal of the Indian Council of Philosophical Research 27 (2). 2010.
    The chapter is divided in two parts. The first part gives an introduction to issues in quantified modal logic . We provide an overview of recent work in QML and we presuppose the use of a relational semantics. We discuss models for constant domains, increasing domains and varying domains and present axiomatizations for the corresponding logics. We also discuss philosophical issues related to the interpretation of the quantifiers, terms and identity and we present a first-order quantified intensi…Read more
  •  25
    Consider a rational agent X at certain point of time t. X's epistemic state can be represented in different ways
  •  18
    Contextual Modals
    with William Taysom
    In a series of recent articles Angelika Kratzer has argued that the standard account of modality along Kripkean lines is inadequate in order to represent context-dependent modals. In particular she argues that the standard account is unable to deliver a non-trivial account of modality capable of overcoming inconsistencies of the underlying conversational background
  •  136
    Daniel Ellsberg presented in Ellsberg (The Quarterly Journal of Economics 75:643–669, 1961) various examples questioning the thesis that decision making under uncertainty can be reduced to decision making under risk. These examples constitute one of the main challenges to the received view on the foundations of decision theory offered by Leonard Savage in Savage (1972). Craig Fox and Amos Tversky have, nevertheless, offered an indirect defense of Savage. They provided in Fox and Tversky (1995) a…Read more
  •  47
  •  32
    In (Hertwig et al. , 2003) Hertwig et al. draw a distinction between decisions from experience and decisions from description. In a decision from experience an agent does not have a summary description of the possible outcomes or their likelihoods. A career choice, deciding whether to back up a computer hard drive, cross a busy street, etc., are typical examples of decisions from experience. In such decisions agents can rely only of their encounters with the corresponding prospects. By contrast,…Read more
  •  45
    Gerd Gigerenzer and Thomas Sturm have recently proposed a modest form of what they describe as a normative, ecological and limited naturalism. The basic move in their argument is to infer that certain heuristics we tend to use should be used in the right ecological setting. To address this argument, we first consider the case of a concrete heuristic called Take the Best (TTB). There are at least two variants of the heuristic which we study by making explicit the choice functions they induce, ext…Read more
  •  23
    It is now well known that, on pain of triviality, the probability of a conditional cannot be identified with the corresponding conditional probability [27]. This surprising impossibility result has a qualitative counterpart. In fact, Peter Gardenfors showed in [13] that believing 'If A then B' cannot be equated with the act of believing B on the supposition that A
  •  100
    The logic of conditionals
    Stanford Encyclopedia of Philosophy. 2007.
    entry for the Entry for the Stanford Encyclopedia of Philosophy, 2007.
  • Review (review)
    Theoria 73 (1): 87-93. 2007.
  •  130
      We present a decision-theoretically motivated notion of contraction which, we claim, encodes the principles of minimal change and entrenchment. Contraction is seen as an operation whose goal is to minimize loses of informational value. The operation is also compatible with the principle that in contracting A one should preserve the sentences better entrenched than A (when the belief set contains A). Even when the principle of minimal change and the latter motivation for entrenchment figure pro…Read more
  •  365
    Your use of the JSTOR archive indicates your acceptance of JSTOR's Terms and Conditions of Use, available at http://www.jstor.org/about/terms.html. JSTOR's Terms and Conditions of Use provides, in part, that unless you have obtained prior permission, you may not download an entire issue of a journal or multiple copies of articles, and you may use content in the JSTOR archive only for your personal, non-commercial use.
  •  23
    Review of Vincent F. Hendricks, Mainstream and Formal Epistemology (review)
    Notre Dame Philosophical Reviews 2006 (7). 2006.
  •  96
    The paper provides a framework for representing belief-contravening hypotheses in games of perfect information. The resulting t-extended information structures are used to encode the notion that a player has the disposition to behave rationally at a node. We show that there are models where the condition of all players possessing this disposition at all nodes (under their control) is both a necessary and a sufficient for them to play the backward induction solution in centipede games. To obtain …Read more
  •  19
    Recent work has shown that in spite of these negative results, the question 'how to accept a conditional?' has a clear answer. Even if conditionals are not truth-carriers, they do have precise acceptability conditions. Nevertheless most epistemic models of conditionals do not provide acceptance conditions for iterated conditionals. One of the main goals of this essay is to provide a comprehensive account of the notion of epistemic conditionality covering all forms of iteration.
  • The Description–Experience Gap in Risky and Ambiguous Gambles
    with Varun Dutt, Jeffrey Helzner, and Cleotilde Gonzalez
    Journal of Behavioral Decision Making 27 (4): 316-327. 2014.
  •  28
    Rationally choosing beliefs: some open questions
    Análisis Filosófico 26 (1): 93-114. 2006.
    Carlos Alchourrón, Peter Gärdenfors and David Makinson published in 1985 a seminal article on belief change in the Journal of Symbolic Logic. Researchers from various disciplines, from computer science to mathematical economics to philosophical logic, have continued the work first presented in this seminal paper during the last two decades. This paper explores some salient foundational trends that interpret the act of changing view as a decision. We will argue that some of these foundational tre…Read more
  •  50
    Synthese 172 (1): 1-6. 2010.
  •  100
    Journal of Philosophical Logic 34, 97-119, 2005.
  •  25
    Similarity in logical reasoning and decision-making
    Behavioral and Brain Sciences 28 (1): 14-15. 2005.
    Normative accounts in terms of similarity can be deployed in order to provide semantics for systems of context-free default rules and other sophisticated conditionals. In contrast, procedural accounts of decision in terms of similarity (Rubinstein 1997) are hard to reconcile with the normative rules of rationality used in decision-making, even when suitably weakened.
  •  41
    One of the reasons for adopting hyperbolic discounting is to explain preference reversals. Another is that this value structure suggests an elegant theory of the will. I examine the capacity of the theory to solve Newcomb's problem. In addition, I compare Ainslie's account with other procedural theories of choice that seem at least equally capable of accommodating reversals of preference.
  •  162
    First-order classical modal logic
    Studia Logica 84 (2). 2006.
    The paper focuses on extending to the first order case the semantical program for modalities first introduced by Dana Scott and Richard Montague. We focus on the study of neighborhood frames with constant domains and we offer in the first part of the paper a series of new completeness results for salient classical systems of first order modal logic. Among other results we show that it is possible to prove strong completeness results for normal systems without the Barcan Formula (like FOL + K)in …Read more
  •  27
    The "Ellsberg phenomenon" has played a significant role in research on imprecise probabilities. Fox and Tversky [5] have attempted to explain this phenomenon in terms of their "comparative ignorance" hypothesis. We challenge that explanation and present empirical work suggesting an explanation that is much closer to Ellsberg's own diagnosis
  •  17
    Building on work that we reported at ISIPTA 2005 we revisit claims made by Fox and Tversky concerning their "comparative ignorance" hypothesis for decision making under uncertainty