The creative energy was called Ahūra Mazda’s beneficent spirit (Spento- Mainyus), and the destructive force was called his maleficent spirit (Angro-Mainyus, afterwards corrupted into Ahriman), but only because the idea of evil is connected with dissolution. The two spirits were merely antagonistic in name. They were in reality co-operative and mutually helpful. They were essential to the alternating processes of construction and dissolution, through which the cosmical being was perpetuated. The only real antagonism was that alternately brought about by the free agent, man, who could hasten the work of destruction, or retard the work of construction by his own acts. It is therefore held, that the so-called dualistic doctrines of Zoroaster were compatible with the absolute unity of the one God (symbolized especially by fire). Ultimately, however, Zoroastrianism crystallized into a hard and uncompromising dualism. That is to say, in process of time, Spento- Mainyus became merely another name for Ahūra Mazda, as the eternal principle of good, while Angro-Mainyus or Ahriman became altogether dissociated from Ahūra Mazda, and converted into an eternal principle of evil. These two principles are believed to be the sources of two opposite creations which were incessantly at war. On the one side is a celestial hierarchy, at the head of which is Ormazd; on the other side, a demoniacal, at the head of which is Ahriman. They are opposed to each other as light to darkness—as falsehood to truth. The whole energy of a religious Indian Pārsī is concentrated on the endeavor to make himself—so to speak—demon-proof, and this can only be accomplished by absolute purity (in thought, word and deed), symbolized by whiteness. He is ever on his guard against bodily defilement, and never goes out to his daily occupation, without first putting on a sacred white shirt and a sacred white girdle. Even the most highly educated and Anglicized Pārsīs are most rigorous observers of this custom, though it is probable that their real creed has little in common with the old and superstitious belief in demons and evil spirits, but rather consists in a kind of cold and monotheistic pantheism.