Page:Popular Science Monthly Volume 34.djvu/454

438 The first great tributary poured into this stream, as we approach, the bloom of the middle ages, appears to have come from the brain of Michael Psellus. Mingling scriptural texts, Platonic philosophy, and theological views of great doctors of the Church, with wild statements obtained from lunatics, he gave forth, about the beginning of the twelfth century, a treatise on "The Work of Demons." "Sacred science" was vastly enriched thereby in various ways; but two of his conclusions, the results of his most profound thought, enforced by theologians and popularized by preachers, soon took a special hold upon the thinking portion of the people at large. The first of these, which he easily based upon Scripture and St. Basil, was that, since all demons suffer by material fire and brimstone, they must have material bodies; the second was that, since all demons are by nature cold, they gladly seek a genial warmth by entering the bodies of men and beasts.

Fed by this stream of thought, and developed in the warm atmosphere of mediæval devotion, the idea of demoniacal possession as the main source of lunacy grew and blossomed and bore fruit in noxious luxuriance.

There had, indeed, come into the middle ages an inheritance of scientific thought. The ideas of Hippocrates, Celius Aurelianus, Galen, and their followers, were from time to time revived; the Arabian physicians, the school of Salerno, such writers as Salicetus, Guy de Chauliac, and even some of the religious orders, did something to keep scientific doctrines alive; but the tide of theological thought was too strong—it became dangerous even to seem to name possible limits to diabolical power. To deny Satan was atheism; and perhaps nothing did so much to fasten the epithet "atheist" upon the medical profession as the suspicion that it did not fully acknowledge diabolical interference in mental disease. Of this feeling we have a monument in the mediæval proverb, "Where there are three physicians there are two atheists."