Kurt Godel (1906-1978)
Kurt Godel was a mathematician and logician. He developed Godel’s Incompleteness Theorem, which demonstrates that all complex logical systems are incomplete and that each of these systems contains, at any given time, more true statements than it can prove using its own defining set of rules. This disproved a belief at the time that all branches of mathematics could be integrated and means that humans can recognize the true meaning of some sentences but the truth of them cannot be derived by any logical system. For indepth biographical information on Godel go to--
http://turnbull.dcs.st-and.ac.uk/~history/Mathematicians/Godel.html or
http://www.exploratorium.edu/complexity/CompLexicon/godel.html
For an explanation of Godel’s Incompleteness Theorem go to--