A major, posthumous work, this book now gives us the thought of Paul Tillich on the whole history of Christianity as a developing religious phenomenon and as the heritage of present-day theology. In this book Tillich not only spans the pre-Christian era and the influence of Greek philosophy, the early Church, medieval Catholicism, and the revolutionary events of the Reformation as they bear upon modern Protestantism, but also covers such major figures of the past 160 years as Kant, Rousseau, Hume, Lessing, Schleirmacher, He- gel, Schelling, Feuerbach, Darwin, Kierkegaard, Marx, Schopenhauer, Nietsche, Erlangen, Martin Kahler, Adolf von Harnack, Bultmann, Troeltsch, and Barth.