But the ancients expressly distinguished, "magic," which was always under suspicion and disapproved of, from the legitimate and honorable art for which the name "theurgy"[68] was invented. The term "magician," ([Greek: magos]) which applied to all performers of miracles, properly means the priests of Mazdaism, and a well attested tradition makes the Persians[69] the authors of the real magic, that called "black magic" by the Middle Ages. If they did not invent it--because it is as old as humanity--they were at least the first to place it upon a doctrinal foundation and to assign to it a place {189} in a clearly formulated theological system. The Mazdean dualism gave a new power to this pernicious knowledge by conferring upon it the character that will distinguish it henceforth. Under what influences did the Persian magic come into existence? When and how did it spread? These are questions that are not well elucidated yet. The intimate fusion of the religious doctrines of the Iranian conquerors with those of the native clergy, which took place at Babylon, occurred in this era of belief,[70] and the magicians that were established in Mesopotamia combined their secret traditions with the rites and formulas codified by the Chaldean sorcerers. The universal curiosity of the Greeks soon took note of this marvelous science. Naturalist philosophers like Democritus,[71] the great traveler, seem to have helped themselves more than once from the treasure of observations collected by the Oriental priests. Without a doubt they drew from these incongruous compilations, in which truth was mingled with the absurd and reality with the fantastical, the knowledge of some properties of plants and minerals, or of some experiments of physics. However, the limpid Hellenic genius always turned away from the misty speculations of magic, giving them but slight consideration. But towards the end of the Alexandrine period the books ascribed to the half-mythical masters of the Persian science, Zoroaster, Hostanes and Hystaspes, were translated into Greek, and until the end of paganism those names enjoyed a prodigious authority. At the same time the Jews, who were acquainted with the arcana of the Irano-Chaldean doctrines and proceedings, made some of the recipes known wherever the dispersion brought {190} them.[72] Later, a more immediate influence was exercised upon the Roman world by the Persian colonies of Asia Minor,[73] who retained an obstinate faith in their ancient national beliefs.