What is the logic of propositional identity?

Charles Sayward

DOI: http://dx.doi.org/10.12775/LLP.2006.001


Propositional identity is not expressed by a predicate. So its logic is not given by the ordinary first order axioms for identity. What are the logical axioms governing this concept, then? Some axioms in addition to those proposed by Arthur Prior are proposed.


propositions; identity; entailment; canceling-out; Geach; Prior; Quine

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