Which C.S. Lewis book presents a series of Christian ideas as connected radio talks?

Mere Christianity presents C.S. Lewis’s Christian ideas as a connected series of radio talks and later book chapters.

The talks were broadcast by the BBC during the Second World War, beginning in 1941. Lewis was asked to explain basic Christian beliefs to a general audience, not to argue for one particular denomination. His clear, conversational style helped make the broadcasts widely accessible.

The material was issued in stages under titles including Broadcast Talks and Christian Behaviour before being collected as Mere Christianity in 1952. The final book is organized into four parts: “Right and Wrong as a Clue to the Meaning of the Universe,” “What Christians Believe,” “Christian Behaviour,” and “Beyond Personality.”

The word “mere” means basic or essential Christianity, rather than something trivial. Lewis’s goal was to discuss beliefs shared by historic Christian traditions. The book remains one of his most frequently read works of Christian apologetics.