Now there ought to be no prejudice _a priori_ against such a theory, which stands on a different footing from what I may call the Vedic fallacy: and it is childish to allow to the Aryan, or any other racial bias, any malignant influence in these difficult discussions. Those who have worked for years upon the marvellously rich records of Mesopotamian culture, whether at first hand or, like myself, at second hand, cannot fail to receive the deepest impression of its imperial grandeur and its forceful vitality, and of its intensity of thought and purpose in the sphere of religion. Naturally, they may feel, such spiritual power must have radiated influence far and wide over the adjacent lands; and no one could maintain that South-Eastern Europe was too remote to have been touched, perhaps penetrated, by it. For we know that, under certain conditions, the race-barrier falls down before the march of a conquering and dominating religion. And now, in the new light of a wider historical survey, instead of saying, as once was said, “What is more its own than a people’s gods?” we {32} may rather ask, “What is less its own than a people’s gods?” always, however, remembering that race-tradition, inherited instinctive feeling and thought, is very strong in these matters, and that a people will, often unconsciously, cling to its ancestral modes of religious consciousness and expression, while it will freely borrow alien forms, names, and ritual. The inquiry indicated by the title of these lectures is naturally twofold; it may be applied either to the earlier or the later periods of the Hellenic and Hellenic-Roman history. The question concerning the later period, though much critical research is needed for its clear solution, is far simpler and more hopeful: for the evidence is immeasurably fuller and more precise, and historical dates and landmarks are there to help. The history of the invasion of the West by Mithraism has been masterfully stated by Cumont; the general influence of the Anatolian religions upon Graeco-Roman society is presented and estimated by the same writer in his _Religious Orientales_; by Toutain, in his _Les Cultes Paiens dans l’Empire Romain_; by our own scholar, Samuel Dill, in _Roman Society in the last Century of the Western Empire_; and more summarily by Salomon Reinach in his _Orpheus_. Therefore I am not going to pursue the inquiry at this end, although I may have to notice and use some of the later evidence. I am going to raise the question concerning the very origins of the Hellenic religious system, so as to test the recently proclaimed dogma of certain Assyriologists, and to determine, if possible, whether the Orient played any formative part in the organic development of Greek religion. For this is just the question which, I venture to maintain, has never yet been critically explored. From what I have said at the beginning, it is obvious that I cannot {33} promise final and proved results.