L'umidità come principio di vita. Trasformazioni medievali di un tema classico fra medicina e filosofia

The idea that life itself can be considered in terms of a continuous tension between heat and moisture has Hippocratic, Aristotelian and Galenic origins. The complete elaboration of the concept of “radical moisture”, though, took place in the Middle Ages, and is linked to Arabic philosophy and medicine, and to the reception of Arabic medical texts in the Latin world. Leaving aside the medieval theological implications of the concept, this essay offers an overview of the different types of moisture in the human body, each of them, according to Galen, performing a specific function and each of them linked to a febrile pathology. Moving from the distinct Aristotelian and Galenic approach to the idea of an inherent consumption of the natural heat of every living thing, and focusing in particular on “ectic” fevers, the paper discusses the contributions of Isaac Israeli, Avicenna and Averroes to the topic.