The Logic of Justification

  • Sergei ArtemovEmail author
Part of the Springer Graduate Texts in Philosophy book series (SGTP, volume 1)


We describe a general logical framework, Justification Logic, for reasoning about epistemic justification. Justification Logic is based on classical propositional logic augmented by justification assertions t: F that read t is a justification for F. Justification Logic absorbs basic principles originating from both mainstream epistemology and the mathematical theory of proofs. It contributes to the studies of the well-known Justified True Belief vs. Knowledge problem. We state a general Correspondence Theorem showing that behind each epistemic modal logic, there is a robust system of justifications. This renders a new, evidence-based foundation for epistemic logic.

As a case study, we offer a resolution of the Goldman-Kripke ‘Red Barn’ paradox and analyze Russell’s ‘prime minister example’ in Justification Logic. Furthermore, we formalize the well-known Gettier example and reveal hidden assumptions and redundancies in Gettier’s reasoning.


Modal Logic Definite Description Epistemic Logic Constant Specification Justify True Belief 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The author is very grateful to Walter Dean, Mel Fitting, Vladimir Krupski, Roman Kuznets, Elena Nogina, Tudor Protopopescu, and Ruili Ye, whose advice helped with this paper. Many thanks to Karen Kletter for editing this text. Thanks to audiences at the CUNY Graduate Center, Bern University, the Collegium Logicum in Vienna, and the 2nd International Workshop on Analytic Proof Systems for comments on earlier versions of this paper. This work has been supported by NSF grant 0830450, CUNY Collaborative Incentive Research Grant CIRG1424, and PSC CUNY Research Grant PSCREG-39-721.


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Authors and Affiliations

  1. 1.Graduate Center CUNYNew YorkUSA

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