A Neighbourhood Semantics for the Logic TK

Cezar A. Mortari, Hércules de Araújo Feitosa


The logic TK was introduced as a propositional logic extending the classical propositional calculus with a new unary operator which interprets some conceptions of Tarski’s consequence operator. TK-algebras were introduced as models to TK. Thus, by using algebraic tools, the adequacy (soundness and completeness) of TK relatively to the TK-algebras was proved. This work presents a neighbourhood semantics for TK, which turns out to be deductively equivalent to the non-normal modal logic EMT4.



Consequence operator; TK algebra; TK logic; neighbourhood semantics.

DOI: https://doi.org/10.5007/1808-1711.2011v15n2p287

Copyright (c)


Principia: an internationnal journal of epistemology
Published by NEL - Epistemology and Logic Research Group
Federal University of Santa Catarina - UFSC
Center of Philosophy and Human Sciences – CFH
Campus Reitor João David Ferreira Lima
Florianópolis, Santa Catarina - Brazil
CEP: 88040-900

 ISSN: 1414-4217
EISSN: 1808-171

e-mail: principia@contato.ufsc.br