Relational semantics for the 4-valued relevant logics BN4 and E4

Gemma Robles, José M. Blanco, Sandra M. López, Jesús R. Paradela, Marcos M. Recio



The logic BN4 was defined by R.T. Brady in 1982. It can be considered as the 4-valued logic of the relevant conditional. E4 is a variant of BN4 that can be considered as the 4-valued logic of (relevant) entailment. The aim of this paper is to define reduced general Routley-Meyer semantics for BN4 and E4. It is proved that BN4 and E4 are strongly sound and complete w.r.t. their respective semantics.


relevant logics; many-valued logics; 4-valued logics; Routley-Meyer semantics

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ISSN: 1425-3305 (print version)

ISSN: 2300-9802 (electronic version)

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