What was the title of C.S. Lewis’s 1960 book about different kinds of love?

The Four Loves was C.S. Lewis’s 1960 book about different kinds of human love. It developed from a BBC radio broadcast series and examines affection, friendship, erotic love, and charity.

Lewis uses Greek terms to distinguish the forms: storge for affection, philia for friendship, eros for romantic or sexual love, and agape for self-giving love. In the book, he generally uses the Greek word “agape” alongside the Christian concept of charity.

The work is not a simple ranking of romantic relationships. Lewis explores the strengths and dangers of each form, arguing that natural loves can become distorted when treated as ultimate or made independent of a larger moral framework.

The book is sometimes confused with Mere Christianity, which also grew from radio broadcasts but focuses on Christian belief and moral reasoning. The Four Loves is specifically organized around categories of love and their effects on human relationships.