A mellow soul with dirty blond hair, a stubbly chin and a surfer’s wardrobe, Muller seems an unlikely Wall Street whiz kid. The investment banking firm Morgan Stanley wooed him away from his adopted hometown of Berkeley, California, after learning of his innovative work in the field of quantitative research. “But I didn’t want to come to New York for that,” Muller says. “So they said, ‘Is there any job you’d come to New York for?’ I said, ‘Sure, if you let me start a trading group.’ ” When they asked if he’d ever done anything like that, Muller said (insouciantly, one imagines) he played a lot of poker. The venerable firm’s response? “What the hell. Let’s try it.”
Muller brought a mathematician’s gift to his group, Process Driven Trading, which manages bank capital. (Muller graduated with honors from Princeton in 1985 with a degree in mathematics and has published papers on heady topics like “equity valuation models” and “financial optimization.” As for poker, Muller was quite serious: He played in the first World Poker Tour tournament, finishing fourth out of 342 contestants.) “I had this great career in finance. I did some things that very few people get to do. I was kind of at the top of the game. I just found that it wasn’t my passion.”
Muller said goodbye to high finance in 2001, at the age of thirty-seven. By then he’d made his fortune and cut his work schedule down to one day per month.