"I gradually grew more convinced of a number of definite points. First, that the milieu of the origin of Zoroaster or, as I was then inclined to think, of the tradition that bore his name, could not be in Chorasmia, either little or great”, ie. reaching as far as Marv and Harat, but must be sought in a region further south. Secondly, that the difference between the milieu of Zoroastrian origins and the cultural, social and political reality of the Achaemenian empire were so marked that they must needs be explained by means of a process of historical evolution that was neither brief nor superficial."