With regard to the origin of the ideas in the Hermetic writings, there is considerable difference of opinion. Reitzenstein allows a large place to Egyptian and Persian elements; other scholars emphasize rather the influence of Greek philosophy, which of course is in turn thought to have been modified by its contact with oriental religion. J. Kroll,[161] W. Kroll,[162] Reitzenstein,[163] and others deny emphatically the presence of any considerable Christian influence in Hermes; but at this point Heinrici, after particularly careful researches, differs from the customary view.[164] Windisch is enough impressed by Heinrici's arguments to confess that Christian literature may have influenced the present form of the Hermetic writings here and there, but insists that the Christian influence upon Hermes is altogether trifling compared to the influence upon primitive Christianity of the type of religion of which Hermes is an example.[165] The true state of the case, according to Windisch, is probably that Christianity first received from oriental religion the fundamental ideas, and then gave back to oriental religion as represented by Hermes certain forms of expression in which those ideas had been clothed. At the same time Windisch urges careful attention to Heinrici's argument for Christian influence upon Hermes for three reasons: (1) all Hermetic writings are later than the New Testament period, (2) the Hermetic writings are admittedly influenced by Judaism, (3) at least the latest stratum in the Hermetic writings has admittedly passed through the Christian sphere. These admissions, coming from one who is very friendly to the modern method of comparative religion, are significant. When even Windisch admits that the form of expression with regard to the new birth in the Poimandres may possibly be influenced by the Gospel tradition, and that the author of the fourth Hermetic tractate, for example, was somewhat familiar with New Testament writings or Christian ideas and "assimilated Christian terminology to his gnosis," and that the term "faith" has possibly come into Hermes (iv and ix) from Christian tradition--in the light of these admissions it may appear how very precarious is the employment of Hermes Trismegistus as a witness to pre-Christian paganism. [161] _Op. cit._ [162] Article "Hermes Trismegistos," in Pauly-Wissowa, _Real-Encyclopädie der classischen Altertumswissenschaft_, xv, 1912, pp. 791-823. [163] _Op. cit._ [164] Heinrici, _Die Hermes-Mystik und das Neue Testament_, 1918. [165] Windisch, "Urchristentum und Hermesmystik," in _Theologisch Tijdschrift_, lii, 1918, pp. 186-240.