Tyler VanderWeele is Professor of Epidemiology at Harvard University and director of its Human Flourishing Program, the center that uses scientific methods to study what makes a life go well. Educated at Oxford, the University of Pennsylvania and Harvard, where he earned his PhD in biostatistics, he has published more than six hundred papers and co-directs the Global Flourishing Study, the largest study of human well-being ever conducted: more than two hundred thousand people in twenty-two countries, followed over five years. Its findings can be uncomfortable: wealthier countries, for instance, score lower on meaning and relationships. His masterclasses are an invitation to look at your own life with a scientist’s precision and a humanist’s depth.