We describe ourselves in terms of books whenever we refer to "reading" another's mind or making a "mental note." Eric Jager expertly traces this self-text metaphor in Western literature and art from ancient to modern times, focusing especially on the Middle Ages, when the metaphor of a "book of the heart" modeled on the manuscript codex attained its most vivid expressions. In a bold conclusion, Jager considers what the much-prophesied "death of the book" might mean for twenty-first-century conceptions of the self.