On truth unpersistence: At the crossroads of epistemic modality and discourse

International audienceWe propose a semantic analysis of the particles afinal (European Portuguese) and alla fine (Italian) in terms of the notion of truth unpersistence, which combines both epistemic modality and constraints on discourse structure. We argue that the felicitous use of these modal particles requires that the truth of a proposition p* fail to persist through a temporal succession of epistemic states, where p* is incompatible with the proposition modified by afinal/alla fine, and that the interlocutors share knowledge of a previous epistemic attitude toward p*. We analyze two main cases, that of plan-related propositions and that of propositions without plans. We also discuss the connections between truth unpersistence and evidentiality

Diagnosing Sorites arguments

This is a discussion of Delia Fara’s theory of vagueness, and of its solution to the Sorites paradox, criticizing some of the details of the account, but agreeing that its central insight will be a part of any solution to the problem. I also consider a wider range of philosophical puzzles that involve arguments that are structurally similar to the argument of the Sorites paradox, and argue that the main ideas of her account of vagueness helps to respond to some of those puzzles. Esta es una discusión sobre la teoría de la vaguedad de Delia Fara, y de su solución a la paradoja de Sorites, criticando alguno de los detalles de su aproximación, pero de acuerdo en que la intuición central es parte de cualquier solución al problema. También considero un rango más amplio de puzles filosóficos que incluyen argumentos estructuralmente similares al argumento de la paradoja de Sorites, y defiendo que las ideas principales de su aproximación a la vaguedad ayudan a responder algunos de esos puzles

Iterated Belief Revision

This is a discussion of the problem of extending the basic AGM belief revision theory to iterated belief revision: the problem of formulating rules, not only for revising a basic belief state in response to potential new information, but also for revising one’s revision rules in response to potential new information. The emphasis in the paper is on foundational questions about the nature of and motivation for various constraints, and about the methodology of the evaluation of putative counterexamples to proposed constraints. Some specific constraints that have been proposed are criticized. The paper emphasizes the importance of meta-information—information about one’s sources of information—and argues that little of substance can be said about constraints on iterated belief revision at a level of abstraction that lacks the resources for explicit representation of meta-information