In the long history of man, not the least interesting moments have been those ebullient and often creative occasions when two of his civilizations have met and mingled. One thinks most readily of the Hellenistic period, that entrancing millennium in the Near East from Alexander to Muhammad, which gave rise to so much ferment and so much of permanent and profound consequence for all our lives. One might think also, perhaps, of “Indo-China,” as designating not a political entity today but a cultural occasion and achievement in the classical past; or of the Muslims of India, who also for a millennium have for good or ill been the children as it were of a broken home—itself based on a shotgun wedding. These, it might be argued, would repay intensive study in our day, for an understanding of intercultural contact, more richly than can the oversimplified instances, dear to the anthropologist, of the one-sided impact of massive, dynamic “civilization” on the so-called underdeveloped cultures of our contemporary “primitives.” Yet these occasions in the past of civilizations in mutual impingement, fascinating though they be and instructive, and deserving, I think, of much more attention than they currently command, nonetheless adumbrate only partially what is happening in our world today. It is something unique that is going on before our eyes.