## Notre Dame Journal of Formal Logic

### Being Wrong: Logics for False Belief

Christopher Steinsvold

#### Abstract

We introduce an operator to represent the simple notion of being wrong. Read Wp to mean: the agent is wrong about p. Being wrong about p means believing p though p is false. We add this operator to the language of propositional logic and study it. We introduce a canonical model for logics of being wrong, show completeness for the minimal logic of being wrong and various other systems. En route we examine the expressiveness of the language. In conclusion, we discuss an open question regarding K4.

#### Article information

Source
Notre Dame J. Formal Logic Volume 52, Number 3 (2011), 245-253.

Dates
First available in Project Euclid: 28 July 2011

http://projecteuclid.org/euclid.ndjfl/1311875772

Digital Object Identifier
doi:10.1215/00294527-1435438

Mathematical Reviews number (MathSciNet)
MR2822487

Zentralblatt MATH identifier
1252.03035

Subjects
Primary: 03B42: Logics of knowledge and belief (including belief change)

#### Citation

Steinsvold, Christopher. Being Wrong: Logics for False Belief. Notre Dame J. Formal Logic 52 (2011), no. 3, 245--253. doi:10.1215/00294527-1435438. http://projecteuclid.org/euclid.ndjfl/1311875772.

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