Avoiding Deontic Explosion by Contextually Restricting Aggregation

  • Joke Meheus
  • Mathieu Beirlaen
  • Frederik Van De Putte
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6181)


In this paper, we present an adaptive logic for deontic conflicts, called P2.1 r , that is based on Goble’s logic SDL a P e—a bimodal extension of Goble’s logic P that invalidates aggregation for all prima facie obligations. The logic P2.1 r has several advantages with respect to SDL a P e. For consistent sets of obligations it yields the same results as Standard Deontic Logic and for inconsistent sets of obligations, it validates aggregation “as much as possible”. It thus leads to a richer consequence set than SDL a P e. The logic P2.1 r avoids Goble’s criticisms against other non-adjunctive systems of deontic logic. Moreover, it can handle all the ‘toy examples’ from the literature as well as more complex ones.


Conflict-tolerant deontic logic non-adjunctive deontic logic deontic explosion defeasible deontic reasoning adaptive logic 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Joke Meheus
    • 1
  • Mathieu Beirlaen
    • 1
  • Frederik Van De Putte
    • 1
  1. 1.Centre for Logic and Philosophy of ScienceGhent UniversityGhentBelgium

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