Journal of Philosophical Logic

, Volume 26, Issue 2, pp 169–180

On the completeness of first degree weakly aggregative modal logics


  • Peter Apostoli
    • Department of PhilosophyUniversity of Toronto

DOI: 10.1023/A:1017940015180

Cite this article as:
Apostoli, P. Journal of Philosophical Logic (1997) 26: 169. doi:10.1023/A:1017940015180


This paper extends David Lewis’ result that all first degree modal logics are complete to weakly aggregative modal logic by providing a filtration-theoretic version of the canonical model construction of Apostoli and Brown. The completeness and decidability of all first-degree weakly aggregative modal logics is obtained, with Lewis’s result for Kripkean logics recovered in the case k=1.

Copyright information

© Kluwer Academic Publishers 1997