Which C.S. Lewis book presents four forms of human love?

C.S. Lewis’s book presenting four forms of human love is The Four Loves.

Published in 1960, The Four Loves developed from a series of BBC radio talks. Lewis examines four Greek terms associated with different kinds of love: affection, friendship, romantic love, and charitable or self-giving love. In the English text, these are commonly discussed as storge, philia, eros, and agape.

The book considers both the strengths and dangers of each form. Affection can become possessive, friendship can become exclusive, romantic love can be idealized, and self-giving love can be misunderstood when detached from other virtues. Lewis’s purpose is not to rank ordinary human relationships simplistically, but to explore how love can be transformed by generosity and moral discipline.

The work is sometimes confused with Mere Christianity because both developed from broadcasts and discuss Christian belief. The Four Loves is more focused: its subject is the vocabulary, experience, and moral shape of love.