Journal of Philosophical Logic

, Volume 31, Issue 6, pp 527–541 | Cite as

A Simple Incomplete Extension of T which is the Union of Two Complete Modal Logics with f.m.p.

  • Roy A. Benton

Abstract

I present here a modal extension of T called KTLM which is, by several measures, the simplest modal extension of T yet presented. Its axiom uses only one sentence letter and has a modal depth of 2. Furthermore, KTLM can be realized as the logical union of two logics KM and KTL which each have the finite model property (f.m.p.), and so themselves are complete. Each of these two component logics has independent interest as well.

complete model property incomplete modal logic union 

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Copyright information

© Kluwer Academic Publishers 2002

Authors and Affiliations

  • Roy A. Benton
    • 1
  1. 1.Departments of Mathematics & PhilosophyColumbia Union CollegeUSA

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