What BBC radio-talk book by C.S. Lewis was published in 1952?

Mere Christianity is the C.S. Lewis book published in 1952 from BBC radio talks.

Lewis delivered the original broadcasts during the Second World War, beginning in 1941. The talks were intended for a broad British audience and explained shared Christian beliefs in accessible language rather than presenting the distinctive doctrines of one denomination.

The material was later revised and collected into books, with Mere Christianity appearing in 1952. Its central discussions include morality, human behavior, repentance, Christian belief, and the relationship between different Christian traditions. The title refers to the common core Lewis believed was shared by historic Christianity.

The book is sometimes described as a transcript of the broadcasts, but the published version was edited and reorganized. It also followed earlier volumes, including Broadcast Talks and Christian Behaviour. Mere Christianity became one of Lewis’s most influential works of Christian apologetics.