Jonathan Fields knows the risks-and potential power-of uncertainty. He gave up a six-figure income as a lawyer to make $12 an hour as a personal trainer. Then, married with a 3-month old baby, he signed a lease to launch a yoga center in the heart of New York City. . . the day before 9/11. But he survived, and along the way he developed a fresh approach to transforming uncertainty, risk of loss, and exposure to judgment into catalysts for innovation,...