C.S. Lewis examines four categories of love in The Four Loves. The book discusses affection, friendship, erotic love, and charity, using the traditional Greek terms storge, philia, eros, and agape as important reference points.
The work began as a series of radio talks for the BBC in 1958 and was published as a book in 1960. Lewis does not treat the four loves as isolated emotions with identical value. Instead, he explores how each can be generous, distorted, dependent, or transformed.
The title’s number is sometimes confused with Lewis’s earlier discussion of three theological virtues or with lists of love categories found in other modern books. The Four Loves is specifically Lewis’s sustained treatment of four human loves and their relationship to divine love, which he calls charity.