In this paper we present two genuine three-valued paraconsistent logics, i.e. logics obeying neither \(p, \lnot p \vdash q\) nor \(\vdash \lnot (p \wedge \lnot p)\). We study their basic properties and their relations with other paraconsistent logics, in particular da Costa’s paraconsistent logics C1 and its extension \(C1+\).
Dedicated to Jair Minoro Abe for his 60th birthday
In [11] we have used k+ because we were also examining the possibilities where the third value was undesignated, using the notation k–.
2.
\(\copyright \) can be implication. In the present paper we are studying logics without implication, so we are comparing these logics with the fragment of C1 without implication.
References
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This paper was written during a stay at University of Tel Aviv within the GeTFun exchange prorgram—Marie Curie project PIRSES-GA-2012-318986 funded by EU-FP7. Thanks to Arnon Avron for his useful comments.
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Authors and Affiliations
UFRJ—Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
Jean-Yves Beziau
CNPq—Brazilian Research Council, Rio de Janeiro, Brazil