Librationist closures of the paradoxes

Frode Bjørdal



We present a semi-formal foundational theory of sorts, akin to sets, named librationism because of its way of dealing with paradoxes. Its semantics is related to Herzberger’s semi inductive approach, it is negation complete and free variables (noemata) name sorts. Librationism deals with paradoxes in a novel way related to paraconsistent dialetheic approaches, but we think of it as bialethic and parasistent. Classical logical theorems are retained, and none contradicted. Novel inferential principles make recourse to theoremhood and failure of theoremhood. Identity is introduced à la Leibniz-Russell, and librationism is highly non-extensional. Π11-comprehension with ordinary Bar-Induction is accounted for (to be lifted). Power sorts are generally paradoxical, and Cantor’s Theorem is blocked as a camouflaged premise is naturally discarded.


Bialethism; Burali-Forti Paradox; Cantor’s Theorem; Curry’s Paradox; Dialetheism; Foundations of Mathematics; Liar’s Paradox; Paraconsistency; Parasistency; Paradoxes; Reverse Mathematics; Russell’s Paradox; Second Order Arithmetic; Semantical paradoxes;

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