Combining Decision Procedures for Positive Theories Sharing Constructors
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 1∪E 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.
KeywordsWord Problem Decision Procedure Equational Theory Positive Theory Free Model
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