PUBLICATIONS DE L'INSTITUT MATHÉMATIQUE (BEOGRAD) (N.S.) Vol. 35(49), pp. 314 (1984) 

NEGATIVE MODAL OPERATORS IN INTUITIONISTIC LOGICKosta DosenMatematicki institut SANU, Beograd, YugoslaviaAbstract: Modal operators which correspond to impossibility and nonnecessity are investigated in systems analogous to the modal logic $K$ which are based on the Heyting propositional calculus. Soundness and completeness are proved with respect to Kripkestyle models with two accessibility relations, one intuitionistic and the other modal. A system where impossibility is equivalent to intuitionistic negation is also proved sound and complete with respect to specific classes of models with two relations. It is shown how the holding of formulae characteristic for this system is equivalent to conditions for the relations of the models. Classification (MSC2000): 03B45 Full text of the article:
Electronic fulltext finalized on: 3 Nov 2001. This page was last modified: 22 Aug 2002.
© 2001 Mathematical Institute of the Serbian Academy of Science and Arts
