The Doctor As Lockean

September 2004 -- Thomas Sydenham (1624-89) was one of London's leading physicians in the latter half of the 17th century. As a follower of Francis Bacon's philosophy, and a close friend of John Locke, Sydenham insisted on an intensely empirical approach to the treatment of disease. For the same reason, however, he remained uninterested in the great anatomical discoveries of his day—and in the bizarre physiological theories to which they gave rise—observing that to a practitioner these theories were useless or worse.

Unfortunately, because of this anti-speculative outlook, Sydenham's reputation has suffered somewhat in recent years.

Life and Works

In 1642, two months after arriving at Oxford, Sydenham left school to fight with the parliamentary forces in the English Civil War, an activity that occupied the next four years. After military service, Sydenham encountered a certain Dr. Coxe, who was treating Sydenham's brother and who persuaded the young man to devote himself to medicine. To that end, Sydenham returned to Oxford in 1647 and remained there for the next eight years, although the medical education he received would have been mostly a study of classical authors, especially Hippocrates and Galen.

In 1655, Sydenham returned to London to practice medicine (and to marry), but seems not to have taken much interest in his career. He ran for Parliament and lost, then received a sinecure from the Commonwealth but lost that at the time of the Restoration in 1660. Apparently, he then went to Montpellier, France, to study medicine for a year. But Sydenham definitely was back in London in 1661, devoting himself to medicine with vigor and intelligence, and in 1663 he made the matter legal by passing the three exams needed for a license from the Royal College of Physicians.

Sydenham's clients were drawn largely from the middle class. So, though he made a considerable reputation and a good income for himself during the 1660s and 1670s, he did not become fabulously wealthy as some high-society doctors did. In the years 1661-64, he also observed the course of various "fever" epidemics in London. During the height of the Great Plague of 1665, he (and his well-to-do clients) left London for the countryside, where Sydenham wrote his first book: Method of Treating Fevers (1666). It was dedicated to Robert Boyle, the founder of the Royal Society, who had given Sydenham the task of studying epidemic fevers, and it was this work that first spread the author's reputation throughout Europe.

Probably, it was also through Boyle that Sydenham met John Locke, who had switched to medicine at Oxford in order to avoid ordination and who had therefore become associated with Boyle's laboratory in High Street. Although Locke never became a doctor of medicine, it was as a physician that in 1666 he met his patron Lord Ashley, later to be the Earl of Shaftesbury, and some have suggested that Locke studied with Sydenham after joining Lord Ashley's household in London. Supporting that theory is a manuscript in Locke's handwriting that contains extracts from Sydenham's works and notes apparently taken from conversations with him. And when a second edition of Sydenham's Method was published in 1668, it contained a commendatory poem from Locke. At any rate, from 1667 to 1671, Sydenham was extremely close to John Locke, and until the end of his life he remained in touch with the philosopher. The "Epistle to the Reader" that precedes Locke's great Essay concerning Human Understanding, lists Sydenham—along with Boyle, Huygens, and Newton—as one of the master-builders "whose mighty designs in advancing the sciences will leave lasting monuments to the admiration of posterity." It is high praise but more of a student's enthusiasm than an objective assessment.

The third edition of Sydenham's work, published in 1676, was renamed Medical observations on the history and cure of acute diseases, and it is the principal source of his fame. The book includes not only the author's observations on the fever epidemics of the early 1660s, but also important observations on scarlet fever, dysentery, and measles. Of the last, it offered by far the best account to date. According to some reports, Medical observations was used as a textbook for the next two centuries. Another, posthumous work, Complete method of curing almost all diseases, remained the English physician's handbook for a century.

The course of Sydenham's life and career seems to have continued in a quiet way, for almost nothing is known of his activities. He did suffer terribly from gout, however, and took the opportunity to write the classic description of the disease, distinguishing it clearly from rheumatism in his Treatise on gout and dropsy, published in 1683.

Although Sydenham was a much-sought-after physician, and although he enjoyed a considerable reputation abroad during his lifetime, his reputation at home was not so high, owing to the fierce medical controversies of the day—Galen still had his advocates—and to his own outspoken personality. "The English Hippocrates" was an epithet given Sydenham during the Enlightenment. One principal promoter of Sydenham's fame was Hermann Boerhaave (1668-1738) of the University of Leiden, the great founder of clinical or "bedside" teaching. Said Boerhaave: "I should blush to mention his name without extolling him."

Methodology

Thomas Sydenham's practice of medicine included three influential elements: an unremitting focus on the living patient; a project to identify and classify diseases, together with the course of each disease; and, not least, a deep skepticism about the powers of a doctor.

The living, striving human being was always at the center of Sydenham's concern. Perhaps this helps explain why he showed little interest in contemporary anatomical discoveries. The metaphor of man as machine has been enormously productive: The heart is a pump; the liver is a chemical factory; the kidneys are filters. But Sydenham's conceptual model was quite different: It was biocentric and teleological. In his view, a patient suffering from an acute disease was a human organism striving toward life but attacked from the outside. The human being was fighting that attack, and the fight was manifest in the disease's symptoms and in its course. The physician's job was to help the person repel the attack.

This was a thoroughly Hippocratic approach, and it led to Sydenham's second great contribution: a movement to create an abstract classification of diseases. If the physician was to help a human body fight against an attack, then he must know precisely what sort of attack was under way and how the body would be fighting it. Thus, the first thing necessary for the physician, Sydenham believed, was to understand that an individual patient's disease was but an instance of a certain species of disease. At root, the similar characteristics of each disease's instances stemmed from their having the same cause and operating on the same human nature. But discovering that deep cause, Sydenham often said, was quite beyond his powers. The classification of disease, therefore, must be carried out on the basis of manifest characteristics. (Lockeanism was not merely empiricism but a shunning of speculation.) Once diseases were classified, physicians could describe the course of each disease so that a doctor might know when and how to assist the body in its fight against the intruder.

This project fit naturally with Sydenham's belief that doctors should be modest about their knowledge and their capacity to effect good on the basis of that knowledge. "It is a great mistake," he wrote in his treatise on gout, "to suppose that Nature always stands in need of the assistance of Art…nor do I think it below me to acknowledge that, when no manifest indication pointed out to me what was to be done, I have consulted the safety of my patient and my own reputation effectually by doing nothing at all."

In sum, Sydenham's advice was: Diagnose the disease; assist the patient's body in its struggle; do no harm. If, at times, Sydenham sounds anti-theoretical, one must remember (to quote a 19th-century biographer) "in the midst of what a mass of errors and prejudices, of theories actively mischievous, he was placed, at a time when the mania of hypothesis was at its height, and when the practical part of his art was overrun and stultified by vile and silly nostrums." Of course, that is obvious only in retrospect. At the time, as at all times, thinkers spinning out hypotheses did not see the error of their ways.

Conclusion

Sydenham's methods were not only useful for the practice of medicine in his day, they are a permanently useful reminder for the practical arts. Extensive observation and abstraction is the road to certain knowledge. But the road is a difficult one; anecdotal knowledge will not suffice. "Sydenham argued that repeated 'experiments' from a large number of cases were needed to establish not only a description of a disease but also its treatment; observations of particular cases were not so useful because the remedy used might only be successful in one or two cases and not universally" (Andrew Wear, Knowledge and Practice in English Medicine, 1550-1680, p. 456). For this reason, the practical arts should proceed cautiously, employing that which has been found to work and adopting only with very great caution the conclusions of abstract reasoning. Thomas Sydenham would have agreed with Artemus Ward: "It ain't so much the things we don't know that get us in trouble, it's the things we know that just ain't so."

This article was originally published in the September 2004 issue of Navigator magazine, The Atlas Society precursor to The New Individualist.  

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