The Vanished Magical Art criticized traditional notions of witchcraft and magic, calling wizards cheaters, magic a chimera, and witches' sabbats ridiculous to anyone who is not stolid. With the help of ancient and more recent authorities, Maffei debunked the profound wisdom and knowledge attributed to witches and the occult sciences and any positive correlation between supernatural spirits and human signs, deeds or words. He too had been considered a magician as he experimented with electricity, later discovering that lightning originates on the earth and not in the sky. How could Christians, Maffei asks, believe that God would willingly allow the Devil to harm, harm, and even kill humans through magic? The work sparked heated debates in the form of 14 theoretical pamphlets that Maffei summarized and discredited in Artemagica annihilata of 1754.