Example image of eyePlorer eyePlorer map for 'Consistency': Logic Theory (mathematical logic) Term logic Well-formed formula Emil Leon Post Induction Kurt Gödel Paul Bernays Predicate logic Propositional calculus Second-order logic Mathematical proof Hilbert's program Proof theory Gödel's incompleteness theorems Curry–Howard correspondence Cut-elimination theorem Normalization property (lambda-calculus) Completeness Peano axioms Presburger arithmetic Primitive recursive arithmetic Zermelo–Fraenkel set theory Formula If and only if Negation Equivalence relation Stephen Cole Kleene Alfred Tarski Hans Reichenbach Jean Van Heijenoort The Cambridge Dictionary of Philosophy Bootstrap model Complete theory Consequentia mirabilis Consistency (negotiation) Delta consistency Dynamic inconsistency Epsilon calculus Fictional universe Finite thickness Forcing (mathematics) GSO projection Haag–Lopuszanski–Sohnius theorem Lindenbaum's lemma List of statements undecidable in ZFC Local consistency Self-verifying theories Size consistency Value system