This man proposed the axiom of foundations and introduced the idea of a proper class to resolve Russell's Paradox. His work on Hilbert's Sixth Problem led him to axiomatize quantum mechanics by viewing physical quantities as 
This man proposed the axiom of foundations and introduced the idea of a proper class to resolve Russell's Paradox. His work on Hilbert's Sixth Problem led him to axiomatize quantum mechanics by viewing physical quantities as operators in a Hilbert space, and with Bernays and Godel he gives his name to a set theory equivalent to Zermelo-Frankel. He proved the minimax theorem characterizing zero-sum games with perfect information, and the equivalence of cellular automata and Turing machines.  In a report on the EDVAC, he introduced a namesake computer architecture. Responsible for introducing backwards induction in Theory of Games and Economic Behavior, FTP identify this Hungarian-born mathematician.
This man proposed the axiom of foundations and introduced the idea of a proper class to resolve Russell's Paradox.
John von Neumann or Margittai Neumann J?os Lajos