Matthieu Ricard trained as a molecular biologist, working in the lab of a Nobel prize--winning scientist, but when he read some Buddhist philosophy, he became drawn to Buddhism. Eventually he left his life in science to study with Tibetan teachers, and he is now a Buddhist monk and translator for the Dalai Lama, living in the Shechen monastery near Kathmandu in Nepal. Trinh Thuan was born into a Buddhist family in Vietnam but became intrigued by the explosion of discoveries in astronomy during the 1960s. He made his way to the prestigious California Institute of Technology to study with some of the biggest names in the field and is now an acclaimed astrophysicist and specialist on how the galaxies formed. When Matthieu Ricard and Trinh Thuan met at an academic conference in the summer of 1997, they began discussing the many remarkable connections between the teachings of Buddhism and the findings of recent science. That conversation grew into an astonishing correspondence exploring a series of fascinating questions. Did the universe have a beginning? Might our perception of time in fact be an illusion, a phenomenon created in our brains that has no ultimate reality? What is consciousness and how did it evolve?