Example image of eyePlorer eyePlorer map for 'Principia Mathematica': Gottlob Frege Paradox Russell's paradox Type theory Universal set Aristotle Organon Philosophy Modern Library Cardinal number Ordinal number Real number Set theory Real analysis Geometry Rudolf Carnap Axiom of choice Axiom of infinity Axiom of reducibility Frank Ramsey Completeness Consistency Proposition Propositional calculus Gödel's completeness theorem Hilbert's second problem Model Gödel's incompleteness theorems Formal system Catch-22 (logic) Ludwig Wittgenstein Information Processing Language Ivor Grattan-Guinness Stanford Encyclopedia of Philosophy Metamath Introduction to Mathematical Philosophy New Foundations Tensor product of graphs Alfred North Whitehead Logic Theorist Emil Leon Post Logicism Louis Couturat Bertrand Russell William Ernest Johnson Enlightenment in Western secular tradition Ancestral relation Haskell Curry Principles of Mathematical Logic Triune Continuum Paradigm