Rigid E-Unification Revisited

  • Ashish Tiwari
  • Leo Bachmair
  • Harald Ruess
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1831)


This paper presents a sound and complete set of abstract transformation rules for rigid E-unification. Abstract congruence closure, syntactic unification and paramodulation are the three main components of the proposed method. The method obviates the need for using any complicated term orderings and easily incorporates suitable optimization rules. Characterization of substitutions as congruences allows for a comparatively simple proof of completeness using proof transformations. When specialized to syntactic unification, we obtain a set of abstract transition rules that describe a class of efficient syntactic unification algorithms.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • Ashish Tiwari
    • 1
  • Leo Bachmair
    • 1
  • Harald Ruess
    • 2
  1. 1.Department of Computer ScienceSUNY at Stony BrookStony BrookU.S.A
  2. 2.SRI InternationalMenlo ParkU.S.A

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