It was the fall of 1990 and Simons was in his office on the thirty-third floor of a midtown Manhattan high-rise, his eyes glued to a computer screen flashing the latest moves in global financial markets. Friends didn’t understand why Simons was still at it. Fifty-two years old, Simons had already lived a full life, enjoying enough adventure, accomplishment, and prosperity to satisfy the ambitions of his peers. Yet, there he was, overseeing an investment fund, sweating the market’s daily eruptions.