During the middle ages the devil was everywhere—ubique dæmon. There was one religious sect whose adepts were ever spitting, hawking, and blowing the nose, with a view to expel the devils they had swallowed. A trace of this still remains in some localities, where one who sneezes is saluted with "God bless you!" Such beliefs were universal. Thus a certain prior of a convent had around him constantly a guard of two hundred men, who hewed the air with their swords, so as to cut to pieces the demons who were assailing him. Demons were even cited to appear before ecclesiastical tribunals.—A curious and a pitiful epoch, when the possessed and their exorcists were madmen alike!
This view of insanity was favored by the philosophical, or rather the theological ideas of the time. According to these, man was of a twofold nature. On the one hand was the flesh, mere matter; on the other, the soul, a direct emanation from Deity, passing through this vale of tears, on its way to the ineffable glory of heaven. The body is but the soul's dwelling-place—a temple or a den, accordingly as its invisible inhabitant is the servant of God or of Satan. Therefore, when the soul is diseased, the treatment must regard the soul alone, which is governed by laws of its own, and is merely in juxtaposition with the body for a moment. No doubt the ideal of purity thus held up was sublime; yet the result of it was the upsetting of the body's equilibrium; and this reacted on the mind. But this theory led to still more serious consequences; for it was admitted into science, and checked the progress of the medical art. When in 1828 Broussais attacked it, he was accused of blasphemy, and of "sapping the foundations" of society. Now, however, we know that the faculties of the mind are not independent of the conditions of the body. Take a slight dose of sulphate of quinine, and you lose, for the time being, the faculty of recollection; swallow a little hashish, and you are transiently insane.
In 1453 Edelin, a priest and doctor of the Sorbonne, preached against the cruelty of putting to death poor creatures who were the dupes of their own diseased imaginations. On being cited to defend himself before a tribunal, he became suddenly insane, and was immured for life, that is, shut up between four walls, without food, drink, or light. In the sixteenth century Europe literally blazed with the fires lighted to punish witches and sorcerers, who were simply mad-men. Luther had a visit from the devil. Pico della Mirandola tells of Savonarola's visions, and Melanchthon holds converse with spirits. Even Ambroise Paré, the Hippocrates of modern times, believed in possession, in compacts with the devil, and the like. The same is to be said of Fernel, famous for his calculation of the earth's dimensions, and of Bodin, the great jurisconsult. These great men, with all their sagacity, with all their learning, would seem never to have heard of the monk Bacon's dictum: "We cannot determine by speculation or by imagination what Nature will do, or what endure; all that must be