Which C.S. Lewis book explores four kinds of love, including agape and storge?

The Four Loves is the C.S. Lewis book that explores agape, storge, philia, and eros.

Published in 1960, The Four Loves developed from a 1958 BBC radio series. Lewis examines four Greek terms and the kinds of human affection they can represent: storge for familial affection, philia for friendship, eros for romantic love, and agape for self-giving love.

The book does not claim that every relationship fits neatly into only one category. Lewis presents the loves as overlapping experiences and considers both their value and their potential distortions when separated from a larger moral framework.

Readers sometimes confuse this work with The Allegory of Love, Lewis’s 1936 academic study of medieval and Renaissance literature. Surprised by Joy is instead Lewis’s spiritual autobiography, while The Weight of Glory is a collection of sermons and essays.