Combining Decision Procedures for Positive Theories Sharing Constructors

  • Franz Baader
  • Cesare Tinelli
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2378)


This paper addresses the following combination problem: given two equational theories E 1 and E 2 whose positive theories are decidable, how can one obtain a decision procedure for the positive theory of E 1E 2? For theories over disjoint signatures, this problem was solved by Baader and Schulz in 1995. This paper is a first step towards extending this result to the case of theories sharing constructors. Since there is a close connection between positive theories and unification problems, this also extends to the non-disjoint case the work on combining decision procedures for unification modulo equational theories.


Word Problem Decision Procedure Equational Theory Positive Theory Free Model 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • Franz Baader
    • 1
  • Cesare Tinelli
    • 2
  1. 1.TU DresdenGermany
  2. 2.University of IowaUSA

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