#4: Grigori Yefimovich Perelman (b. 1966)
This reclusive Russian mathematician solved the Poincaré Conjecture, one of the world’s most complex math problems, and was offered a $1 million prize. He declined both the award and scientific celebrity, retreating into obscurity. His refusal baffled colleagues, but cemented his reputation as one of the most brilliant—and enigmatic—minds of modern times.
