Amphitheism is undoubtedly the most rational of all forms of belief in God, and the one which is least incompatible with a scientific view of the world. Hence we find it elaborated in many ancient peoples thousands of years before Christ. In ancient India Vishnu, the preserver, struggles with Shiva, the destroyer. In ancient Egypt the good Osiris is opposed by the wicked Typhon. The early Hebrews had a similar dualism of Aschera (or Keturah), the fertile mother-earth, and Elion (Moloch or Sethos), the stern heavenly father. In the Zend religion of the ancient Persians, founded by Zoroaster two thousand years before Christ, there is a perpetual struggle between Ormuzd, the good god of light, and Ahriman, the wicked god of darkness. In Christian mythology the Devil is scarcely less conspicuous as the adversary of the good deity, the tempter and seducer, the prince of hell, and lord of darkness. A personal devil was still an important element in the belief of most Christians at the beginning of the nineteenth century. Towards the middle of the century he was gradually eliminated by being progressively explained away, or he was restricted to the subordinate _rôle_ he plays as Mephistopheles in Goethe's great drama. To-day the majority of educated people look upon "belief in a personal devil" as a mediæval superstition, while "belief in God" (that is, the personal, good, and loving God) is retained as an indispensable element of religion. Yet the one belief is just as much (or as little) justified as the other. In any case, the much-lamented "imperfection of our earthly life," the "struggle for existence," and all that pertains to it, are explained much more simply and naturally by this struggle of a good and an evil god than by any other form of theism.