The Reformation of the Eyes: Apparitions and Optics in Sixteenth- and Seventeenth-Century Europe

Apparitions were the subject of fierce theological and philosophical debate in the period after the Reformation. But these controversies also raised issues fundamental to the nature and organization of human vision. They crossed and recrossed the boundaries between religion and the science and psychology of optics. Apparitions, after all, are things that appear, and spectres are things that are seen. Before they could mean anything to anyone they had to be correctly identified as phenomena. Their religious role, whether Protestant or Catholic, presupposed a perceptual judgement — essentially visual in character — about just what they were. During the early modern period this judgement — this visual identification — became vastly more complex and contentious than ever before, certainly much more so than in the case of medieval ghosts. The sceptics, natural magicians, and atheists turned apparitions into optical tricks played by nature or human artifice; the religious controversialists and demonologists thought that demons might also be responsible. This essay argues that the debate that ensued, irrespective of the confessional allegiances of the protagonists, was the occasion for some of the most sustained and sophisticated of the early modern arguments about truth and illusion in the visual world.