Predicate logic is an extension of propositional logic. Here we consider what is called first-order predicate logic, abbreviated FOL (sometimes abbreviated PL1, not to be confused with the programming ...
Studia Logica: An International Journal for Symbolic Logic, Vol. 103, No. 3 (June 2015), pp. 623-638 (16 pages) Within a weak system WKVS of intuitionistic analysis one may prove, using the Weak Fan ...