The Greek language and the Greek literature spread behind the march of Alexander; but as his generals could only make their conquests permanent by largely accepting the Eastern manners, so philosophy could only make good its ground by becoming itself Orientalised. The one pure and holy God whom Plato had painfully reasoned out for himself had existed from immemorial time in the traditions of the Jews; while the Persians, who had before taught the Jews at Babylon the existence of an independent evil being, now had him to offer to the Greeks as their account of the difficulties which had perplexed Socrates. Seven centuries of struggle, and many hundred thousand folios, were the results of the remarkable fusion which followed. Out of these elements, united in various proportions, rose successively the Alexandrian philosophy, the Hellenists, the Therapeutae, those strange Essene communists, with the innumerable sects of Gnostic or Christian heretics. Finally, the battle was limited to the two great rivals, under one or other of which the best of the remainder had ranged themselves--Manicheism and Catholic Christianity: Manicheism in which the Persian--Catholicism in which the Jewish--element most preponderated. It did not end till the close of the fifth century, and it ended then rather by arbitration than by a decided victory which either side could claim. The Church has yet to acknowledge how large a portion of its enemy's doctrines it incorporated through the mediation of Augustine before the field was surrendered to it. Let us trace something of the real bearings of this section of the world's Oriental history, which to so many moderns seems no better than an idle fighting over words and straws.