Kurt Godel

one of the inspirations for Godel Escher Bach

mathematician

lived 1906-1978! wow that's recent - which means he was still alive while Godel Escher Bach was being worked on (since it was published 1979)

He was a deep logician whose most famous work was the Incompleteness Theorem stating that any self-consistent axiomatic system powerful enough to describe integer arithmetic will allow for propositions about integers that can neither be proven nor disproven from the axioms. http://www.wikipedia.org/wiki/Kurt_Godel

http://xkcd.com/468/