However, although resistance to sensuality is laudable and although the ideal of perfection of this Mazdean sect inclined towards the asceticism to which the Manichean conception of virtue led, yet good does not consist exclusively in abnegation and self-control, but also in action. It is not sufficient for a religion to classify moral values, but in order to be effective it must furnish motives for putting them into practice. Dualism was peculiarly favorable for the development of individual effort and human energy; here its influence was strongest. It taught that the world is the scene of a perpetual struggle between two powers that share the mastery; the goal to be reached is the disappearance of evil and the uncontested dominion, the exclusive reign, of the good. Animals and plants, as well as man, are drawn up in two rival camps perpetually hostile, and all nature participates in the eternal combat of the two opposing principles. The demons created by the infernal spirit emerge constantly from the abyss and roam about the earth; they penetrate everywhere carrying corruption, distress, {158} sickness and death. The celestial spirits and the supporters of piety are compelled constantly to baffle their ever renewed enterprises. The strife continues in the heart and conscience of man, the epitome of the universe, between the divine law of duty and the suggestions of the evil spirits. Life is a merciless war knowing no truce. The task of the true Mazdean consisted in constantly fighting the evil in order to bring about the gradual triumph of Ormuzd in the world. The believer was the assistant of the gods in their work of purification and improvement.