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Intuitionistic Conditional Logics


Building on recent work by Yale Weiss, we study conditional logics in the intuitionistic setting. We consider a number of semantic conditions which give rise, among others, to intuitionistic counterparts of Lewis’s logic VC and Stalnaker’s C2. We show how to obtain a sound and complete axiomatization of each logic arising from a combination of these conditions. On the way, we remark how, in the intuitionistic setting, certain classically equivalent principles of conditional logic come apart, and how certain logical connections between different principles no longer hold.

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The authors would like to thank two anonymous reviewers for precious comments on a previous version of this paper, as well as the audience at the LoRI -VII conference in Chongqing for inspiring discussions.

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Correspondence to Ivano Ciardelli or Xinghan Liu.

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Ciardelli, I., Liu, X. Intuitionistic Conditional Logics. J Philos Logic 49, 807–832 (2020).

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  • Conditional logic
  • Intuitionistic logic
  • Variably strict conditionals
  • Modal logic
  • Non-monotonic reasoning