Across history, our understanding of God, the soul, spirituality, and even science itself has shifted dramatically. Today, we have more scientific knowledge than ever, yet some age-old questions persist: Why do we believe in gods, souls, and rituals? Are these beliefs innate? Do existential fears drive us toward or away from religion? What can we learn about spirituality from children? How can we leverage scientific thinking to study spirituality? This book invites you into the labs and minds of some of the world's most renowned psychological scientists for an in-depth look at how psychologists can study religion and spirituality-and how they wrestle with doubts about ostensibly established findings and methods, even as the field advances. From China, India, Brazil, the United Kingdom, the United States, and Tuva, this book takes a balanced perspective on a diverse range of experiments and studies, casting a light on both their brilliance and their limitations. Ultimately, this book reveals that psychological experiments that test spiritual beliefs are works of imagination that can help us discover truths about the human mind's proclivity for religious ideas, as long as we can adapt and learn along the way.