This ambitious new work, the first of its kind, traces the development of theories of the self and personal identity from the ancient Greeks to the present. Raymond Martin and John Barresi explore the works of a wide range of thinkers and reveal the larger intellectual trends, disputes, and ideas that have revolutionized the way we think about ourselves. Is there a unitary self that remains fixed and unchanged? Does the concept of the soul have a use outside religious contexts? Are notions of the soul and the self still viable in today's world? Beginning with ancient Greece, where the ideas of Plato and Aristotle laid the groundwork for future theories, the authors consider the ways in which thinkers have grappled with these questions. Martin and Barresi continue with a discussion of the ideas of the church fathers and medieval and Renaissance philosophers, including St. Paul, Augustine, Aquinas, and Boethius. From the eighteenth century to the present day, there has been a gradual shift away from religious and philosophical notions of the self to more scientific and social conceptions. The authors explore how developments in modern philosophy and psychology have altered conceptions of the self. In the twentieth century, feminism and gender and ethnic studies have contributed still more ways of conceptualizing the self. Meanwhile, Derrida and others have challenged the very idea that a unified self or personal identity exists at all.