Studia Logica

, Volume 49, Issue 4, pp 501–514 | Cite as

Models for relevant modal logics

  • André Fuhrmann


Semantics are given for modal extensions of relevant logics based on the kind of frames introduced in [7]. By means of a simple recipe we may obtain from a class FRM (L) of unreduced frames characterising a (non-modal) logic L, frame-classes FRM (L.M) characterising conjunctively regular modal extensions L.M of L. By displaying an incompleteness phenomenon, it is shown how the recipe fails when reduced frames are under consideration.


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Copyright information

© Polish Academy of Sciences 1990

Authors and Affiliations

  • André Fuhrmann
    • 1
  1. 1.Universität Konstanz Zentrum Philosophie und WissenschaftstheorieKonstanzW. Germany

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