This book will help you think more analytically. Doing so will enable you to better understand the world around you, to make smarter decisions, and to ultimately live a more fulfilling life. It draws on the maxims of Richard Zeckhauser, a legendary Harvard professor, who has helped hundreds of students and colleagues progress toward these goals. These maxims, one-sentence nuggets of wisdom that capture key principles for clear and effective thinking, are illustrated with practical examples from Richard’s colleagues and students. From these examples, you will learn how one colleague saved money on her wedding by thinking probabilistically, how Richard and his wife Sally made an agonizing health decision that significantly boosted Sally’s survival probabilities, and how the prime minister of Singapore, Lee Hsien Loong, used a maxim he learned from Richard 40 years ago to understand and deal with COVID-19 in his nation. This book provides vital insights for anyone who wants to think more effectively about the world.