Quantified Equilibrium Logic and Hybrid Rules

  • Jos de Bruijn
  • David Pearce
  • Axel Polleres
  • Agustín Valverde
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4524)


In the ongoing discussion about combining rules and Ontologies on the Semantic Web a recurring issue is how to combine first-order classical logic with nonmonotonic rule languages. Whereas several modular approaches to define a combined semantics for such hybrid knowledge bases focus mainly on decidability issues, we tackle the matter from a more general point of view. In this paper we show how Quantified Equilibrium Logic (QEL) can function as a unified framework which embraces classical logic as well as disjunctive logic programs under the (open) answer set semantics. In the proposed variant of QEL we relax the unique names assumption, which was present in earlier versions of QEL. Moreover, we show that this framework elegantly captures the existing modular approaches for hybrid knowledge bases in a unified way.


Logic Program Classical Logic Description Logic Intuitionistic Logic Predicate Symbol 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Berlin Heidelberg 2007

Authors and Affiliations

  • Jos de Bruijn
    • 3
  • David Pearce
    • 1
  • Axel Polleres
    • 1
    • 4
  • Agustín Valverde
    • 2
  1. 1.Universidad Rey Juan Carlos, MadridSpain
  2. 2.Universidad de Málaga, MálagaSpain
  3. 3.DERI Innsbruck, InnsbruckAustria
  4. 4.DERI Galway, National University of Ireland, Galway 

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