What is the name of C.S. Lewis’s autobiographical book about his spiritual conversion?

C.S. Lewis’s autobiographical book about his spiritual conversion is Surprised by Joy. Published in 1955, the book recounts major stages of Lewis’s intellectual and religious development, including his childhood imagination, education, service in the First World War, and movement from atheism toward Christianity.

The title refers to Lewis’s idea of “joy,” a sharp, fleeting experience of longing that he associated with beauty, literature, and the desire for something beyond ordinary satisfaction. Surprised by Joy is not a conventional day-by-day autobiography; it is a selective account organized around the experiences and ideas Lewis considered important to his conversion.

Lewis’s conversion developed over several years. He returned to belief in God in 1929 and became a Christian in 1931, influenced by conversations and friendships that included J.R.R. Tolkien and Hugo Dyson. Readers sometimes confuse this book with Mere Christianity, which presents arguments and radio talks about Christian belief rather than serving primarily as Lewis’s autobiography.