Which C.S. Lewis book presents Christian ideas through conversations and radio-style talks?

Mere Christianity presents C.S. Lewis’s Christian ideas through conversations and radio-style talks.

The book grew out of broadcast talks Lewis delivered for the BBC during the Second World War. The talks were later revised and published in book form, first as separate volumes and then together as Mere Christianity in 1952.

Lewis’s aim was to explain beliefs shared by major Christian traditions rather than argue for one denomination. He discusses morality, human behavior, Christian doctrine, and the implications of belief in God. The conversational style helped make complex religious arguments accessible to a broad wartime radio audience.

The title does not mean a minimal or watered-down Christianity. “Mere” refers to the common core of beliefs Lewis sought to describe. The book is one of his best-known works of Christian apologetics and remains distinct from his fictional works such as The Chronicles of Narnia.