Which C.S. Lewis book records his reflections on conversion and faith?

Surprised by Joy records C.S. Lewis’s reflections on his conversion and faith. Published in 1955, it is an autobiographical work describing important stages in Lewis’s intellectual and spiritual development.

The book follows Lewis from childhood through his education, service in the First World War, academic career, and movement toward Christianity. It discusses the powerful experiences of longing and joy that Lewis associated with moments of imagination, literature, and beauty.

Lewis had been an atheist for a period before returning to Christianity. He described conversations with fellow scholars, including J.R.R. Tolkien and Hugo Dyson, as significant in his changing views. Surprised by Joy does not function as a conventional day-by-day autobiography; instead, it emphasizes the ideas and experiences that shaped his beliefs.

The title uses “joy” in Lewis’s specialized sense of an intense desire or longing that ordinary experiences cannot fully satisfy. Readers sometimes mistake the book for a general memoir, but its main focus is Lewis’s spiritual and intellectual journey.