A note on resolution: How to get rid of factoring without loosing completeness

  • Helga Noll
Friday Morning
Part of the Lecture Notes in Computer Science book series (LNCS, volume 87)


It is often useful to simplify the resolution inference system by elimination of factoring. Factoring, however, cannot be ignored entirely without loosing completeness. This paper studies to what extent factoring is necessary to preserve it. We can show that it is sufficient to factorize only one of the two parent clauses of a resolvent. We apply this basic result to a class of well known refinements and describe for each rule which clause (the so called "selected parent") has at most to be factored.

We try to achieve the results in a transparent manner using only elementary notions of resolution theory, so that this note should be readable without detailed knowledge of resolution strategies.


theorem proving resolution factoring first order logic 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1980

Authors and Affiliations

  • Helga Noll

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