Imaginary Creatures Causing Real Diseases: Projective Etiology in Medieval and Early Modern Medicine

From a contemporary point of view, the causes of most diseases are well-known or can, in some way, be scientifically related to environmental factors and genetic disposition. However, this is a fairly recent development and in the Middle Ages and Early Modern Time people were not, for example, aware of the existence of microscopical, invisible entities as germs causing contagion and transmitting diseases. For this reason, when the explanations provided theories of Hippocrates and Galen – still extremely influential at the time – were not considered satisfactory or when a condition was not simply labelled as divine punishment, medieval and early modern people (and ancient people before them) did not behave much differently from what we still do (consider, for example, the thriving on the internet of the theories linking autism and vaccines!) and found other, more imaginative, explanations for the onset of a given pathology or of its symptoms. In doing this, the responsibility for real diseases and symptoms was often projected onto imaginary creatures, such as worms. In this way, toothache was, for example, ascribed to worms eating the tooth from the inside and, therefore, causing pain. In this study, I focus on these imaginative projective etiologies and on how people elaborated on them (e.g. classifying worms according to color and size, or claiming to have seen them), taking into consideration a corpus of both medical and magical (e.g. charms aimed at healing the pathology they caused) Germanic texts from the Middle Ages and Early Modern Age and paying particular attention to both their origin and their survival in popular belief.