LEO-II - A Cooperative Automatic Theorem Prover for Classical Higher-Order Logic (System Description)

  • Christoph Benzmüller
  • Lawrence C. Paulson
  • Frank Theiss
  • Arnaud Fietzke
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5195)


LEO-II is a standalone, resolution-based higher-order theorem prover designed for effective cooperation with specialist provers for natural fragments of higher-order logic. At present LEO-II can cooperate with the first-order automated theorem provers E, SPASS, and Vampire. The improved performance of LEO-II, especially in comparison to its predecessor LEO, is due to several novel features including the exploitation of term sharing and term indexing techniques, support for primitive equality reasoning, and improved heuristics at the calculus level. LEO-II is implemented in Objective Caml and its problem representation language is the new TPTP THF language.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Christoph Benzmüller
    • 1
  • Lawrence C. Paulson
    • 2
  • Frank Theiss
    • 1
  • Arnaud Fietzke
    • 3
  1. 1.Dep. of Computer ScienceSaarland UniversitySaarbrückenGermany
  2. 2.Computer LaboratoryThe University of CambridgeUK
  3. 3.Max Planck Institute for Informatics SaarbrückenGermany

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