Example image of eyePlorer eyePlorer map for 'Skolem's paradox': Löwenheim–Skolem theorem Mathematical logic Philosophy Absoluteness (mathematical logic) Thoralf Skolem Antinomy Paradox Russell's paradox Axiomatic system Consistency Countable set First-order logic Set theory Structure (mathematical logic) Satisfiability and validity Ernst Zermelo Hilary Putnam Cantor set Georg Cantor Natural number Power set Real number Uncountable set Bijection Cantor's theorem Inner model Morley's categoricity theorem Von Neumann–Bernays–Gödel set theory Finitism Metamathematics Second-order logic Infinitary logic Von Neumann universe Compactness theorem Gödel's completeness theorem Higher-order logic Gödel's incompleteness theorems Forcing (mathematics) Philosophy of mathematics Stephen Cole Kleene Continuum hypothesis Model theory List of paradoxes