Peter Gray is an American psychologist and research professor at Boston College, who is best known for his work in the field of developmental and educational psychology. His research often focuses on the role of play in human evolution and children's learning and development. He authored the widely used introductory psychology textbook, 'Psychology', which takes a unique and engaging approach to teaching the principles of psychology. Additionally, Gray is a prominent advocate for self-directed education and the unschooling movement, highlighting the importance of children’s natural curiosity and ability to direct their own learning. He has published articles and books on the subject, including 'Free to Learn,' in which he argues for the need to create learning environments that optimize children's innate desire to explore and learn about the world around them.