Man, in his ignorance, supposed that all phenomena were produced by some intelligent powers, and with direct reference to him. To preserve friendly relations with these powers was, and still is, the object of all religions. Man knelt through fear and to implore assistance, or through gratitude for some favor which he supposed had been rendered. He endeavored by supplication to appease some being who, for some reason, had, as he believed, become enraged. The lightning and thunder terrified him. In the presence of the volcano he sank upon his knees. The great forests filled with wild and ferocious beasts, the monstrous serpents crawling in mysterious depths, the boundless sea, the flaming comets, the sinister eclipses, the awful calmness of the stars, and, more than all, the perpetual presence of death, convinced him that he was the sport and prey of unseen and malignant powers. The strange and frightful diseases to which he was subject, the freezings and burnings of fever, the contortions of epilepsy, the sudden palsies, the darkness of night, and the wild, terrible and fantastic dreams that filled his brain, satisfied him that he was haunted and pursued by countless spirits of evil. For some reason he supposed that these spirits differed in power--that they were not all alike malevolent--that the higher controlled the lower, and that his very existence depended upon gaining the assistance of the more powerful. For this purpose he resorted to prayer, to flattery, to worship and to sacrifice. These ideas appear to have been almost universal in savage man. For ages all nations supposed that the sick and insane were possessed by evil spirits. For thousands of years the practice of medicine consisted in frightening these spirits away. Usually the priests would make the loudest and most discordant noises possible. They would blow horns, beat upon rude drums, clash cymbals, and in the meantime utter the most unearthly yells. If the noise-remedy failed, they would implore the aid of some more powerful spirit.