Free You Could Look It Up by Jack Lynch Page A

when it is lacking.” 8 The first book brings Greek medicine to bear on the basic principles of anatomy, health, and illness. The four humors—blood, phlegm, yellow bile, and black bile—were introduced and linked to the four elements—earth, air, fire, and water. Disease emerges from an imbalance of the humors, usually because of some obstruction. To bring them into balance, he prescribed “emetics, cathartics, enemas, sedatives, and other drugs, bleeding, blistering, and cauterization.” 9
    The second book moves on to “simples,” the basic medicines that are not compounded of multiple ingredients, and it spells out Avicenna’s conception of what we have come to call the scientific method. Book 3 explores pathology, with a systematic overview of twenty-one bodily organs or systems, while book 4 looks at other sorts of pathologies that span the entire body. This is the part that also introduces the rudiments of surgery. Finally, book 5 provides advice on compounding simples into more sophisticated medicines. Some have called it “the first pharmacopeia,” with its discussion of more than 760 medicines. 10
    A medical historian writes of the book’s “practical tenor”: “Ibn Sina’s intent, all too successful, was to give practitioners ready guidelines for immediate application, without too much worry over theory, and with a minimum of skeptical doubt or radical experimentation.” 11 Another describes how the book works as a reference source:

    If one wishes to use the Canon as a reference tool, the arrangement … works well for some subjects… . One can, for example, relatively easily find an answer to any of the following questions: When and in what conditions is bleeding an appropriate treatment? What are the medicinal powers of cinnamon? What treatments are recommended for deafness? For various kinds of fevers? How is theriac compounded? 12

    The Qanun is less useful, though, in its anatomical discussions, which are scattered throughout the book and therefore ill-suited to quick reference.
    Expectations about medical knowledge were very different a thousand years ago. We now demand our medical textbooks be as up-to-date as possible, but Avicenna, like most writers of his time, demanded ancient authority. “The Qanun ,” one scholar explains, “remains a compendium largely of traditional material.” 13 Avicenna, for instance, leaned heavily on Galen, whose work was eight centuries old when Avicenna wrote—and even Galen was mostly backward-looking at the time he wrote. Still, Avicenna made some conceptual breakthroughs that are now a standard part of medical thinking. Medicines, for instance, Avicenna argued, should be tested before they are tried—“The experiment must be done on a single, not a composite, condition. In the latter case, if the condition consists of two opposite diseases and the drug is tried and found beneficial in both, we cannot infer the real cause of the cure”—an anticipation of what would become the clinical trial. Predating later medical thought, he suggested that tiny organisms might be responsible for illnesses centuries before science offered a germ theory. He called for explicit attention to observation and experimentation, and he believed in treating the whole patient, integrating body and mind into one concern, making him a forerunner of modern medical practice, including the field of psychiatry.
    In fact Avicenna is a forerunner of much later medical thinking. He wrote in Arabic, but the Qanun eventually made its way into many of the world’s languages, including Persian, Latin (Gerard of Cremona rendered it as Canon medicinæ ), Chinese ( Huihui yaofang , or Prescriptions of the Hui Nationality ), and Hebrew, as well as most of the majorlanguages of Europe. It continued to be used—not as a work of antiquarian interest, but as a real medical reference—even into the seventeenth and early eighteenth centuries in Europe. Even today, some practitioners of