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The learned men and priests among the Persians who worshipped light or fire as the emblem of the invisible God, who cultivated a knowledge of astronomy and the secrets of nature, and to whom were attributed the wielding of mysterious powers, and the practice of divination; the followers of Zoroaster, who held two principles, one of good, and the other of evil.

[Gr.] The hereditary priests among the ancient Persians and Medians. Zoroaster is said to have been the great reformer of their order. See Ahriman.