This dualistic strand of thinking dominated during {156} the Middle Ages. The world is given over to the devil for him to work his will upon it. Here we have both a cause and an effect of the pessimism of the times. For the early Christians, society was corrupt and filled with abominations; the only sure way to achieve salvation was to flee from its lure to deserts and monasteries, there to purge the soul of fleshly desires. No one has painted the situation more keenly and unflinchingly than Anatole France in _Thais_. Humanity was sick. A strong wave of asceticism spread from the East to the West and carried with it doctrines based on the metaphysical extension of the contrast between light and darkness, good and evil. Matter is evil in its very nature and leagues itself with those instincts in the soul which come from its contamination with flesh. The taint of original sin is deepened by the grossness of the material out of which man's earthly tabernacle is made. The body with its passions plays double traitor to the soul. Only by prayer, purification, fasting, and the grace of God can the son of corruption save his soul alive for the heavenly kingdom among the stars. The number of mythical elements woven into this ascetic dualism is striking. Woman was the temptress most to be feared; the daughters of Eve were considered the most powerful instruments Satan had at his command. It was even debated whether she had a soul. It was even whispered that a woman guarded the gates of Hell. Again, Satan was pictured as a demon leading the unwary astray by the desires of this world. Ethics was an affair of external fighting for the souls of men. The whole setting was mythical and supernaturalistic and full of picture-thinking. {157}