What is the title of C.S. Lewis’s 1950 Christian apologetics book based on wartime radio talks?

C.S. Lewis’s 1950 Christian apologetics book based on wartime radio talks is Mere Christianity. The book presents a case for shared Christian beliefs rather than defending one specific denomination.

The work grew out of radio broadcasts Lewis delivered for the BBC during the Second World War. The talks were intended for a broad British audience and used clear, conversational arguments about morality, belief, and Christian doctrine. Lewis later revised and expanded the material for publication.

Mere Christianity is often confused with Lewis’s other nonfiction books. The Problem of Pain examines suffering, Miracles discusses the supernatural, and Surprised by Joy is an autobiographical account of his intellectual and religious development. The title “mere” refers to what Lewis regarded as common Christianity: central beliefs held across many Christian traditions, not a diminished or incomplete form of faith.