Of the Greek Fathers who followed Athanasius, I have only room to mention Gregory of Nyssa, who defends the historical incarnation in true mystical fashion by an appeal to spiritual experience. "We all believe that the Divine is in everything, pervading and embracing it, and dwelling in it. Why then do men take offence at the dispensation of the mystery taught by the Incarnation of God, who is not, even now, outside of mankind?... If the _form_ of the Divine presence is not now the same, we are as much agreed that God is among us to-day, as that He was in the world then." He argues in another place that all other species of spiritual beings must have had their Incarnations of Christ; a doctrine which was afterwards condemned, but which seems to follow necessarily from the Logos doctrine. These arguments show very clearly that for the Greek theologians Christ is a cosmic principle, immanent in the world, though not confined by it; and that the scheme of salvation is regarded as part of the constitution of the universe, which is animated and sustained by the same Power who was fully manifested in the Incarnation. The question has been much debated, whether the influence of Persian and Indian thought can be traced in Neoplatonism, or whether that system was purely Greek.[151] It is a quite hopeless task to try to disentangle the various strands of thought which make up the web of Alexandrianism. But there is no doubt that the philosophers of Asia were held in reverence at this period. Origen, in justifying an esoteric mystery-religion for the educated, and a mythical religion for the vulgar, appeals to the example of the "Persians and Indians." And Philostratus, in his life of Apollonius of Tyana, says, or makes his hero say, that while all wish to live in the presence of God, "the Indians alone succeed in doing so." And certainly there are parts of Plotinus, and still more of his successors, which strongly suggest Asiatic influences.[152] When we turn from Alexandria to Syria, we find Orientalism more rampant. Speculation among the Syrian monks of the third, fourth, and fifth centuries was perhaps more unfettered and more audacious than in any other branch of Christendom at any period. Our knowledge of their theories is very limited, but one strange specimen has survived in the book of Hierotheus,[153] which the canonised Dionysius praises in glowing terms as an inspired oracle--indeed, he professes that his own object in writing was merely to popularise the teaching of his master. The book purports to be the work of Hierotheus, a holy man converted by St. Paul, and an instructor of the real Dionysius the Areopagite. A strong case has been made out for believing the real author to be a Syrian mystic, named Stephen bar Sudaili, who lived late in the fifth century. If this theory is correct, the date of Dionysius will have to be moved somewhat later than it has been the custom to fix it. The book of the