 Church-Turing Thesis |  Gödel, Kurt |  Hilbert, David: program in the foundations of mathematics |  logic, history of: intuitionistic logic |  logic: second-order and higher-order |  mathematics, philosophy of |  mathematics, philosophy of: intuitionism |  proof theory |  proof theory: development of |  recursive functions |  set theory |  set theory: independence and large cardinals |  Turing machines |  Wittgenstein, Ludwig: philosophy of mathematics 