Open Access
Winter 1999 Which Modal Logic Is the Right One?
John P. Burgess
Notre Dame J. Formal Logic 40(1): 81-93 (Winter 1999). DOI: 10.1305/ndjfl/1039096306


The question, "Which modal logic is the right one for logical necessity?," divides into two questions, one about model-theoretic validity, the other about proof-theoretic demonstrability. The arguments of Halldén and others that the right validity argument is S5, and the right demonstrability logic includes S4, are reviewed, and certain common objections are argued to be fallacious. A new argument, based on work of S\lupecki and Bryll, is presented for the claim that the right demonstrability logic must be contained in S5, and a more speculative argument for the claim that it does not include S4.2 is also presented.


Download Citation

John P. Burgess. "Which Modal Logic Is the Right One?." Notre Dame J. Formal Logic 40 (1) 81 - 93, Winter 1999.


Published: Winter 1999
First available in Project Euclid: 5 December 2002

zbMATH: 0972.03018
MathSciNet: MR1811204
Digital Object Identifier: 10.1305/ndjfl/1039096306

Primary: 03B45

Rights: Copyright © 1999 University of Notre Dame

Vol.40 • No. 1 • Winter 1999
Back to Top