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A Unified Logic for Contingency and Accident

Journal of Philosophical Logic volume 51, pages 693–720 (2022)Cite this article

Abstract

As shown in Fan (Journal of Philosophical Logic, 48, 425–445, 2019), there are some similarities/resemblances between contingency and accident. Given this, one may naturally ask if we can unify the two operators to manifest all of their similarities/resemblances. In this article, instead of looking at the interactions between the two operators like in Fan (Journal of Philosophical Logic, 48, 425–445, 2019), we turn our attention to the resemblances between the two operators. We extend the unification method in Fan (Logic Journal of the IGPL, 2020) to the current setting. The main results include some model-theoretical ones, such as expressivity, frame definability, bisimulation, and some axiomatization ones.

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Acknowledgements

This research is supported by the project 17CZX053 of National Social Science Foundation of China. The author would like to thank two anonymous referees of this journal for insightful comments on an earlier version of this paper.

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Authors and Affiliations

  1. Institute of Philosophy, Chinese Academy of Sciences, Beijing, China

    Jie Fan

  2. School of Humanities, University of Chinese Academy of Sciences, Beijing, China

    Jie Fan

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  1. Jie Fan
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Correspondence to Jie Fan.

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Fan, J. A Unified Logic for Contingency and Accident. J Philos Logic 51, 693–720 (2022). https://doi.org/10.1007/s10992-021-09647-z

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  • DOI: https://doi.org/10.1007/s10992-021-09647-z

Keywords

  • Contingency
  • Accident
  • Expressivity
  • Frame definability
  • Bisimulation
  • Axiomatizations
  • Public announcements
  • Unification