Richard Feynman was one of the most brilliant, influential, and iconoclastic physicists in the post-World War II era. He was born in May 11th, 1918 in Far Rockaway, New York, USA and died in February 15th, 1988 in Los Angeles, California, USA. He grew up in Manhattan and when he was about 12, he was already fixing radios in his neighborhood. Feynman was one of the engaging and delightful physics teachers. I had the opportunity to attend many of his relating entertaining and revealing lectures on conceptual physics. He always tried to explain in his lectures (at Caltech and UCLA) the most complex principles of physics in a very simple, conceptual manner (The Feynman diagrams in quantum electrodynamics is just one example).
Soon after the World War II, Feynman was invited as a visiting professor to the University of Rio de Janeiro, Brazil. He subsequently accepted a professorship of theoretical physics at the California Institute of Technology in 1950, but loved Brazil so much that one of his conditions was to be able to visit Brazil again. As a result, he did not actually start lecturing at Caltech until 1951. While in Brazil, Feynman lectured about electromagnetism for ten months, at the same time preparing to parade in the carnival of a samba school in Copacabana, Rio de Janeiro. Check out more on Feynman's biography.
Check out a clip from NOVA's "The Best Mind Since Einstein" on Feynman's discussion about the knowing about answers.