The Four Loves examines affection, friendship, eros, and charity. C.S. Lewis’s book was published in 1960 and developed from a series of BBC radio talks about the nature of human love.
Lewis uses Greek terms to distinguish kinds of love that English often groups under one word. Storge refers to natural affection, philia to friendship, eros to romantic or sexual love, and agape to self-giving love. In the book, Lewis usually uses the term charity for the highest form, following older Christian and theological vocabulary.
The work is not a scientific taxonomy or a claim that real relationships contain only one category. Lewis presents the forms as overlapping ways of understanding love, while also warning that natural loves can become possessive or distorted when treated as ultimate.
The book is sometimes confused with Mere Christianity because both originated in broadcast talks. Mere Christianity developed from wartime broadcasts, whereas The Four Loves came from a later series and was published as a separate book.