A Note on the Intuitionistic Logic of False Belief


  • Tomasz Witczak University of Silesia, Faculty of Science and Technology, Institute of Mathematics, Bankowa 14, 40-007 Katowice, Poland https://orcid.org/0000-0002-1178-3691




Intuitionistic modal logic, non-normal modal logic, neighborhood semantics


In this paper we analyse logic of false belief in the intuitionistic setting. This logic, studied in its classical version by Steinsvold, Fan, Gilbert and Venturi, describes the following situation: a formula $\varphi$ is not satisfied in a given world, but we still believe in it (or we think that it should be accepted). Another interpretations are also possible: e.g. that we do not accept $\varphi$ but it is imposed on us by a kind of council or advisory board. From the mathematical point of view, the idea is expressed by an adequate form of modal operator $\mathsf{W}$ which is interpreted in relational frames with neighborhoods. We discuss monotonicity of forcing, soundness, completeness and several other issues. Finally, we mention the fact that it is possible to investigate intuitionistic logics of unknown truths.


J. Fan, Notes on neighborhood semantics for logics of unknown truths and false beliefs (2020), arXiv:2002.09622, math.LO.
Google Scholar

D. Gilbert, G. Venturi, Neighborhood Semantics for Logics of Unknown Truths and False Beliefs, The Australasian Journal of Logic, vol. 14(1) (2017), pp. 246–267, DOI: https://doi.org/10.26686/ajl.v14i1.4033
Google Scholar DOI: https://doi.org/10.26686/ajl.v14i1.4033

C. Steinsvold, Being Wrong: Logics for False Belief, Notre Dame Journal of Formal Logic, vol. 52(3) (2011), pp. 245–253, DOI: https://doi.org/10.1215/00294527-1435438
Google Scholar DOI: https://doi.org/10.1215/00294527-1435438

N. O. T. Dalmonte, Ch. Grellois, Intuitionistic non-normal modal logics: A general framework, Journal of Philosophical Logic, vol. 49 (2020), pp. 833–882, DOI: https://doi.org/10.1007/s10992-019-09539-3.
Google Scholar DOI: https://doi.org/10.1007/s10992-019-09539-3

E. Żabski, Logiki nihilistyczne, czyli teorie prawd "powierzchownych" i "głebokich", Oficyna Wydawnicza Politechniki Wrocławskiej, Wrocław (2001).
Google Scholar




How to Cite

Witczak, T. (2021). A Note on the Intuitionistic Logic of False Belief. Bulletin of the Section of Logic, 51(1), 57–71. https://doi.org/10.18778/0138-0680.2021.20



Research Article