## Notre Dame Journal of Formal Logic

### A Basic System of Congruential-to-Monotone Bimodal Logic and Two of Its Extensions

I. L. Humberstone

#### Abstract

If what is known need not be closed under logical consequence, then a distinction arises between something's being known to be the case (by a specific agent) and its following from something known (to that subject). When each of these notions is represented by a sentence operator, we get a bimodal logic in which to explore the relations between the two notions.

#### Article information

Source
Notre Dame J. Formal Logic, Volume 37, Number 4 (1996), 602-612.

Dates
First available in Project Euclid: 16 December 2002

Permanent link to this document
https://projecteuclid.org/euclid.ndjfl/1040046144

Digital Object Identifier
doi:10.1305/ndjfl/1040046144

Mathematical Reviews number (MathSciNet)
MR1446231

Zentralblatt MATH identifier
0883.03010

#### Citation

Humberstone, I. L. A Basic System of Congruential-to-Monotone Bimodal Logic and Two of Its Extensions. Notre Dame J. Formal Logic 37 (1996), no. 4, 602--612. doi:10.1305/ndjfl/1040046144. https://projecteuclid.org/euclid.ndjfl/1040046144

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