Abstract
The aim of this paper is to introduce a new approach to the modal operators of necessity and possibility. This approach is based on the existence of two negations in certain lattices that we call bi-Heyting algebras. Modal operators are obtained by iterating certain combinations of these negations and going to the limit. Examples of these operators are given by means of graphs.
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Reyes, G.E., Zolfaghari, H. Bi-Heyting algebras, toposes and modalities. Journal of Philosophical Logic 25, 25–43 (1996). https://doi.org/10.1007/BF00357841
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DOI: https://doi.org/10.1007/BF00357841