Medicine in Europe and the United States

Until the seventeenth century, medicine operated within the context of the Galenic blood system, or rather, two blood systems. Using chyle (concocted in the stomach from food), the liver produced venous blood, which moved through the veins to various parts of the body to provide for nourishment and growth. The heart was the source of arterial blood, a concoction of venous blood, and pneuma (vital air, the stuff of life), which also moved through the body as needed. The venous blood seeped from the right side to the left side of the heart through invisible pores in the interventricular septum. The air came from the lungs via the venal artery (today's pulmonary vein). Blood did not return to the heart but was consumed: no circulation. This coherent, rational system, concordant with major therapies, also explained mental functions by diverting a little arterial blood for conversion into animal spirits (highly refined spirituous air) to flow though the nervous system.

Movement of the heart and blood.

Harvey was a Cambridge man who took his medical degree at Padua, where he worked under Girolamo Fabrici (Fabricius ab Aquapendente; c. 1533–1619), the first anatomist to discuss the venous valves (De venarum ostiolis; 1603). By the time Harvey arrived in Padua, Galen's model had been seriously damaged, though no one had thrown Galen's works into a bonfire, as Paracelsus had supposedly done with Avicenna's Canon in 1527. Vesalius had denied the origin of the vena cava in the liver and, in the second edition of De humani corporis fabrica, the theory of the porous septum in the heart. After some vivisectionist experiments, Columbo argued for the pulmonary transit, or movement of blood though the lungs, and also described accurately the action of the heart in systole and diastole. Other anatomists confirmed these discoveries.

On his return to England, Harvey practiced in London, becoming one of the city's most famous doctors and after 1618 one of the royal physicians. De motu cordis does not introduce its great novelty, the circulation of the blood, until chapter eight, and then only apologetically in an Aristotelian, vitalistic framework. Unlike René Descartes (1596–1650), Harvey was not a mechanist. His work was based on dissection, vivi-section, and a famous quantitative experiment in which he measured the amount of blood passing thorough the heart in a given time, thus showing that the system had to circulate the same blood or explode. Of course Harvey's argument on circulation was incomplete because he could not see the capillaries, though he inferred their existence; Marcello Malphighi (1628–1694) used a microscope to discover them in a frog's lungs (On the Lungs, 1661). Robert Hooke (1635–1703) as well as an Oxford group pinpointed the importance of the mixing of air and blood in the lungs. (An explanation of respiration, completing the system, was not possible before the chemical revolution of the late eighteenth century.) Galenic physiology, with the liver as a blood-making organ, became untenable, as Jean Riolan the Younger (1580–1657) recognized in a weak scientific attack on Harvey, who had little trouble in showing it to be nonobservational nonsense. Physicians were too conservative to abandon the Galenic practice of venesection, and this points to a problem of new medical science: the development of a related therapy is usually in the future, leaving doctor and patient both victims of the old science with its traditional therapeutics.

Paracelsus: Crude chemotherapy.

The end of Galen's iconic status was balanced by a revival of Hippocrates, the perfect cover for an attack on orthodoxy. Paracelsus (Bombast von Hohenheim; 1493–1541) denounced learned medicine but praised Hippocrates, a curious patron for his brand of medicine based on the Christian religion, magic, astrology, observation, and personal experience. Ackerknecht called him a "medical Doctor Faustus" (p. 108). Paracelsus's cosmic "doctrine of signatures" identified the curative power of plants according to their resemblance to the organ affected; this was a pretty standard belief in popular medicine as well. In his natural philosophy, the Aristotelian-Galenic system of qualities, elements, and humors was replaced by a chemical fantasy associating substances with principles of solidity (salt), inflammability (sulfur), and spirituousness (mercury). Specific remedies of this chemical therapy cured specific diseases, whose agents might be poisons from the stars or from minerals on earth. Paradoxically, the advocate of the idea of a chemical etiology of and cure for diseases is the culture hero of alternative medicine. He was antiestablishment. Reading deeply into the book of nature, he concluded that therapy should be based on the principle of "like cures like": applying what is suitable to the affected part, rather than following Galenic therapeutics based on the principle of opposition. Paracelsus had many followers, the most famous being Jan Baptista van Helmont (1579–1644), master of medical chemistry (iatrochemistry) and defender of the ontological concept of disease, meaning that every disease has its own unique principle and therefore a specific treatment. The theory was useful in attacking blood-letting as a debilitating practice based on the erroneous idea that plethora causes disease. But like its Galenic enemy, Paracelsan iatrochemistry declined in the second half of the seventeenth century. The choleric Harvey, no friend of chemistry, regarded the Paracelsans as "shitt-breeches."

Sydenham: Bedside medicine.

Unlike Harvey, Thomas Sydenham (1624–1689) was on the winning side in the English Civil War. Unlike Harvey, he did not have any scientific manuscripts for soldiers to destroy. Sydenham, an Oxford man scornful of learned medicine, advocated observation and the bedside tradition. His hero was Hippocrates, reinvented as an inspiring clinical spirit at the bedside. The "English Hippocrates" believed in specific remedies for diseases; cinchona bark against the ague (benign tertian malaria), for example. Unlike Harvey, Sydenham, accepting Francis Bacon's (1561–1626) philosophy of science, was interested in classifying diseases, epidemic fevers in particular; the botanical model was useful here in his attempt to develop a clinical medicine for the London masses who suffered from the ague from March to July. In the midst of these conceptual upheavals on the functioning of the body and the nature of diseases, therapeutics changed little, except that a "new" disease like syphilis might require a "new" and horrible treatment (mercury). Herbal remedies continued in both popular and professional use. The old humoral procedures of bleeding, purging, induced vomiting, blistering, and cupping survived in the medical repertory. No wonder Sydenham admitted that without opium, medicine was a cripple. (Sydenham's laudanum contained 200 grams of opium, 100 grams of saffron, and 15 grams each of cinnamon and of cloves in 100 grams of Malaga wine.) Sydenham doubted that using the microscope or studying anatomy would advance medicine. Prophecy should be left to the prophets.