The custom of carrying the sacred fire before the Caesars as an emblem of the perpetuity of their power, dated back to Darius and with other Persian traditions passed on to the dynasties that divided the empire of Alexander. There is a striking similarity not only between the observance of the Caesars and the practice of the Oriental monarchs, but also between the beliefs that they held. The continuity of the political and religious tradition cannot be doubted.[4] As the court ceremonial and the internal history of the Hellenistic kingdoms become better known we shall be able to outline with greater precision the manner in which the divided and diminished heritage of the Achemenides, after generations of rulers, was finally left to those Occidental sovereigns who called themselves the sacrosanct lords of the world as Artaxerxes had done.[5] It may not be generally known that the habit of welcoming friends with a kiss was a ceremony in the {138} Oriental formulary before it became a familiar custom in Europe.[6] It is very difficult to trace the hidden paths by which pure ideas travel from one people to another. But certain it is that at the beginning of our era certain Mazdean conceptions had already spread outside of Asia. The extent of the influence of Parseeism upon the beliefs of Israel under the Achemenides cannot be determined, but its existence is undeniable.[7] Some of its doctrines, as for instance those relating to angels and demons, the end of the world and the final resurrection, were propagated everywhere in the basin of the Mediterranean as a consequence of the diffusion of Jewish colonies. On the other hand, ever since the conquests of Cyrus and Darius, the active attention of the Greeks had been drawn toward the doctrines and religious practices of the new masters of the Orient.[8] A number of legends representing Pythagoras, Democritus and other philosophers as disciples of the magi prove the prestige of that powerful sacerdotal class. The Macedonian conquest, which placed the Greeks in direct relations with numerous votaries of Mazdaism, gave a new impetus to works treating that religion, and the great scientific movement inaugurated by Aristotle caused many scholars to look into the doctrines taught by the Persian subjects of the Seleucides. We know from a reliable source that the works catalogued under the name of Zoroaster in the library of Alexandria contained two million lines. This immense body of sacred literature was bound to attract the attention of scholars and to call forth the reflections of philosophers. The dim and dubious science that reached {139} even the lower classes under the name of "magic" was to a considerable extent of Persian origin, as its name indicates, and along with physician's recipes and thaumaturgic processes it imparted some theological doctrines in a confused fashion.[9]