Which C.S. Lewis book presents four forms of love, including affection and friendship?

The Four Loves presents four forms of love, including affection and friendship.

C.S. Lewis’s The Four Loves was published in 1960. It grew from a 1958 BBC radio series and examines four Greek terms used to distinguish kinds of love: storge, philia, eros, and agape. Lewis discusses them as affection, friendship, romantic or sexual love, and charitable or self-giving love.

The book is not a simple ranking in which one form replaces all the others. Lewis explores the strengths and dangers of each, including the way natural loves can become possessive or distorted when treated as ultimate.

The Four Loves is sometimes confused with Mere Christianity because both address Christian belief and morality for a general audience. However, its organizing subject is love, and its four-part framework is the defining feature of this later work.