Слабая транзитивность - реституция.


L.L. Esakia


The purpose of this paper is a restitution of a longstanding notion of weak-transitivity and a modal system, which may be identified with the set of formulas valid in all weak-transitive Kripke models. The modal system has a finite models property and can be axiomatized quite simple: it is the smolest normal logic to contain all instances of the formula $p\& \square p\rightarrow\square\square p$. The modal system is an especially interesting as the logic of all topological spaces provided that the limit-operation, a fundamental topological notion, is treated as the diamond modality.






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