Hildegard of Bingen, the 12th century Rhineland visionary, includes a remedy for jaundice in her extensive writings on medical topics. She advises the sufferer to wear a stunned bat (yes, of the mammalian kind) around his neck until the bat expires. To our modern sensibilities this recommendation seems useless at best but it was a treatment that was in keeping with the medieval understanding of human physiology and illness. That understanding had originated with Hippocrates (460-377BC) and Aristotle (384-324BC) and had been transmitted to the West via the writings of Galen (129-216AD) whose approach dominated the theory and practice of medicine throughout the Middle Ages.
Following Galen, Hildegard regarded the human body as a microcosm of the vast macrocosm of the known universe which was believed to be made up of four elements: Earth, Fire, Water and Air. All things – animate and inanimate – were composed of various combinations of these elements and of their contraries: cold, hot, moist, and dry. Particular combinations of any two of the contraries produced in each and every person one of four main Complexions or Temperaments and an accompanying predominant bodily fluid (humor). Illness was understood as a disturbance in these humors and treatment sought to restore humeral balance. An overabundance of blood in the system, for example, was often treated by the application of leeches. Herbs, with their own particular humeral qualities, were a popular treatment as was careful attention to the patient’s diet.
Hildegard seems to have been an expert in the understanding and application of humeral theory. Among her many writings is a book of (medieval) “natural science”, Causae et Curae, in which she gives authoritative advice on treatment for all manner of ailments. For example, she recommends (a form of) the tansy herb to treat catarrh, and a brew of comfrey, marigold, wild sage and yarrow for easing pain associated with bruising following trauma. Apples were a staple medicine. When cooked they were considered to be very beneficial for sick persons in general while a salve made from apple leaves was especially good for the eyes. No doubt this earlier medicinal use of apples is part of the basis for our present-day saying, “an apple a day keeps the doctor away.” Mind you, apples are a lot easier to come by than bats. And I can’t help but wonder what I might have to do to “stun” a bat!