NEXP-Completeness and Universal Hardness Results for Justification Logic

Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9139)


We provide a lower complexity bound for the satisfiability problem of a multi-agent justification logic, establishing that the general NEXP upper bound from our previous work is tight. We then use a simple modification of the corresponding reduction to prove that satisfiability for all multi-agent justification logics from there is \(\varSigma _2^p\)-hard – given certain reasonable conditions. Our methods improve on these required conditions for the same lower bound for the single-agent justification logics, proven by Buss and Kuznets in 2009, thus answering one of their open questions.


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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.The Graduate Center of CUNYNew YorkUSA

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