1887-1963

Norwegian mathematician best known for his contributions to mathematical logic. The Skolem-Löwenheim theorem established that any class of formulas simultaneously satisfiable is also satisfiable in a denumerably infinite domain (1920). Skolem realized this led to a paradox—the apparent conflict between a set's magnitude in axiomatic theory and its magnitude in the more limited domain it is modeled in (1922). Skolem resolved the paradox by treating certain set-theoretic concepts, such as non-denumerability, as relative.