The Higher-Order Prover Leo-III

  • Alexander SteenEmail author
  • Christoph Benzmüller
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10900)


The automated theorem prover Leo-III for classical higher-order logic with Henkin semantics and choice is presented. Leo-III is based on extensional higher-order paramodulation and accepts every common TPTP dialect (FOF, TFF, THF), including their recent extensions to rank-1 polymorphism (TF1, TH1). In addition, the prover natively supports almost every normal higher-order modal logic. Leo-III cooperates with first-order reasoning tools using translations to many-sorted first-order logic and produces verifiable proof certificates. The prover is evaluated on heterogeneous benchmark sets.


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Authors and Affiliations

  1. 1.Institute of Computer ScienceFreie Universität BerlinBerlinGermany
  2. 2.Computer Science and CommunicationsUniversity of LuxembourgEsch-sur-AlzetteLuxembourg

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