No one has given the polymath Thomas Young (1773–1829) the all-round examination he so richly deserves—until now. Celebrated biographer Andrew Robinson portrays a man who solved mystery after mystery in the face of ridicule and rejection, and never sought fame. As a physicist, Young challenged the theories of Isaac Newton and proved that light is a wave. As a physician, he showed how the eye focuses and proposed the three-colour theory of vision, only confirmed a century and a half later. As an Egyptologist, he made crucial contributions to deciphering the Rosetta Stone. It is hard to grasp how much Young knew. This biography is the fascinating story of a driven yet modest hero who cared less about what others thought of him than for the joys of an unbridled pursuit of knowledge—with a new foreword by Martin Rees and a new postscript discussing polymathy in the two centuries since the time of Young. It returns this neglected genius to his proper position in the pantheon of great scientific thinkers.