Medieval Drugs III: How Do I Drug Thee? Let Me Count the Ways.

This is my third and final post about medieval drugs. A big “thanks” to Joe Gabriel for recommending Points to me and to Trysh Travis for giving me a soapbox for sharing some of my interests and original research with the Points community!

Among the favorite stock images of modern medicine are the scientifically dosed drug, measured in identical pills or graduated syringes, and the thermometer. While both are modern inventions, the hypodermic syringe and thermometer reflect a tendency, shared by later medieval Islamic and European physicians, to quantify drugs, their qualities, and medicinal actions. The tendency to quantify drugs, common by the end of the Middle Ages, is the third stage in the process I proposed in my first post, by which herbal medicines were transformed into “drugs” by physicians, pharmacists, and patients who began to look at their medicines in new ways. That transformation took a number of forms and for a variety of reasons, which I’ve grouped under the themes of individualism, exoticism, and scholasticism in these three posts.

The accurate measurement of drugs, in terms of both their strength and quantity, is central to modern medicine, and began in the High Medieval universities.

By “scholasticism” I mean the intellctual processes of subjecting pharmaceutical remedies to the philosophy and science taught in the schools and universities, especially mathematics and Aristotelian physics. Universities were an invention of the High Middle Ages, a way of organizing the already present schoolmasters and students into corporations with more effective legal, economic, academic, and even spiritual powers. By about 1225 the cities of Paris, Oxford, Cambridge, Bologna, Padua, Salamanca, and Montpellier all had thriving universities. These universities provided the social and economic foundations for novel thinking about matter and physics in general, and about drugs in particular.

One of the most important developments in the medieval university, and one with a direct impact on modern science and medicine, was the practice of applying mathematics to non-spatial concepts, like heat or speed. Before the universities, these concepts could only be measured qualitatively (that pot is hotter, that horse is faster), and not quantitatively. Since Aristotle had considered quantity and quality different categories of definition, and not to be mixed, it took a huge mental leap for mental scholars to make the connection as step out of Aristotle’s shadow. If you want to quantify speed or heat, you need to develop the idea of velocity or temperature, respectively. This may sound downright modern and “scientific”, but medieval physicists took the idea of quantification and ran with it. Masters in Oxford, especially, tried to quantify non-spatial concepts that have no place in modern science: one tried to measure doubt on a sliding scale, another to measure the amount of charity in a man, and another even the amount of Christ in the Eucharistic host (yes, these are all real).

The “modernity” of medicine is often depicted by quantification, as in dosage, or body temperature.

These are extreme examples, but they’re indicative of a broad trend in Western society outlined by Alfred W. Crosby in his book The Measure of Reality. He identifies quantification as one of the most important changes in Europe in the period 1250-1600. He doesn’t really touch on medicine, but quantification changed that field as well. In this context, it’s hardly surprising that scholars of pharmacy would also want to measure exactly the amount of hot, cold, wet, or dry (Aristotle’s four elemental qualities) in a medicinal substance. 

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