My description of this complicated change is, of course, inadequate, but not, I hope, one-sided. I do not depreciate the religions that followed on this movement by describing the movement itself as a 'failure of nerve'. Mankind has not yet decided which of two opposite methods leads to the fuller and deeper knowledge of the world: the patient and sympathetic study of the good citizen who lives in it, or the ecstatic vision of the saint who rejects it. But probably most Christians are inclined to believe that without some failure and sense of failure, without a contrite heart and conviction of sin, man can hardly attain the religious life. I can imagine an historian of this temper believing that the period we are about to discuss was a necessary softening of human pride, a _Praeparatio Evangelica_.[124:1] I am concerned in this paper with the lower country lying between two great ranges. The one range is Greek Philosophy, culminating in Plato, Aristotle, the Porch, and the Garden; the other is Christianity, culminating in St. Paul and his successors. The one is the work of Hellas, using some few foreign elements; the second is the work of Hellenistic culture on a Hebrew stock. The books of Christianity are Greek, the philosophical background is Hellenistic, the result of the interplay, in the free atmosphere of Greek philosophy, of religious ideas derived from Egypt, Anatolia, Syria, and Babylon. The preaching is carried on in Greek among the Greek-speaking workmen of the great manufacturing and commercial cities. The first preachers are Jews: the central scene is set in Jerusalem. I wish in this essay to indicate how a period of religious history, which seems broken, is really continuous, and to trace the lie of the main valleys which lead from the one range to the other, through a large and imperfectly explored territory. The territory in question is the so-called Hellenistic Age, the period during which the Schools of Greece were 'hellenizing' the world. It is a time of great enlightenment, of vigorous propaganda, of high importance to history. It is a time full of great names: in one school of philosophy alone we have Zeno, Cleanthes, Chrysippus, Panaetius, Posidonius. Yet, curiously enough, it is represented in our tradition by something very like a mere void. There are practically no complete books preserved, only fragments and indirect quotations. Consequently in the search for information about this age we must throw our nets wide. Beside books and inscriptions of the Hellenistic period proper I have drawn on Cicero, Pliny, Seneca, and the like for evidence about their teachers and masters. I have used many Christian and Gnostic documents and works like the Corpus of Hermetic writings and the Mithras Liturgy. Among modern writers I must acknowledge a special debt to the researches of Dieterich, Cumont, Bousset, Wendland, and Reitzenstein. * * * * *