Bad Medicine

By SHERWIN B. NULAND

Noga Arikha’s “Passions and Tempers” illustrates some of the rewards and some of the pitfalls of historical scholarship. To Arikha’s immense credit, she provides a thoroughly documented account of the ways in which a wrong-headed theory dominated medical thinking for more than 2,000 years, refusing to yield place at the bedside long after it had been proved erroneous by clear-eyed observation and the development of experimental science. One of Arikha’s contributions to the general reader’s knowledge, in fact, is to use the history of the humors — those bodily fluids once thought to hold the key to understanding human health and personality — to demonstrate the difficulty that physicians have always had in giving up outmoded ways of treating actual patients. This has almost invariably been the case, even when not only the theoretical but also the practical basis for a changed approach has already been established, sometimes by the very clinicians who cannot bring themselves to abandon the discredited practices. Arikha is hardly treading new ground here, but she does provide convincing and very specific evidence of a human failing that dogged the profession until at least the middle of the 20th century, and in certain ways continues to influence modern-day diagnosis and therapy.
The complex of notions constituting the background of Arikha’s narrative would eventually form the basis from which Western scientific medicine emerged. Its preliminary formulations were brought together over the course of several centuries, in a body of writings that came to be associated with the name of Hippocrates, born on the Greek island of Kos around 460 B.C. But its ultimate codification was the work of the great physician Galen, who lived in the Roman Empire from about A.D. 130 to 201, leaving behind a multitude of texts with claims stated so authoritatively that his influence did not begin to dissipate until the 16th century. Galen’s primary theory was that of the four humors — blood, yellow bile, black bile and phlegm, each related to one of the so-called elements of which all matter was thought to be composed (fire, air, earth and water), embodying the qualities of hot, dry, cold and wet. In this hypothetical system, an individual maintains health so long as the humors remain in a state of equilibrium within the body. Sickness occurs when, for any of a variety of reasons, one of the humors becomes excessive or deficient in quantity. Therapy was aimed at restoring the balance.
Galen believed that not only the state of health but also the general temperament of each individual is determined by the degree to which one or another humor predominates in his distinctive nature. Blood quickens the spirit; yellow bile emboldens it; black bile makes it melancholy; and phlegm makes it sluggish. Accordingly, an individual might have a basic personality that is predominantly sanguine, choleric, bilious or melancholic, words in our language that can be traced to the Greek or Latin roots of the humors associated with them.
Though prominent physicians occasionally took bold issue with humoralism over the passing centuries, the abiding confidence in its all-encompassing legitimacy remained undisturbed as the unproved and unprovable matrix of medical theory. It wasn’t seriously challenged until 1543, when the 28-year-old Belgian professor Andreas Vesalius of the University of Padua pointed out some 200 errors in Galen’s description of anatomy, due primarily to its having been based not on direct observation of the human body but on fanciful suppositions and leaps of imagination after the dissection of animals. As the scientific revolution of the 17th century took hold, Galenic conceptions of physiology were increasingly challenged by observers willing to abandon the overarching hypothetical constructs and systems of the past. These older ways of thinking were gradually replaced by theories arising from the many small observations that might be used in an inductive method of reasoning. In medicine, the ultimate moment in this process of change came in 1628, when the English physician William Harvey published a small volume describing a series of experiments that led to his discovery of the circulation of the blood, and the role played in it by the pumping action of the heart.
The death knell of Galen’s authority had been sounded, and indeed the death knell of the acceptance of any form of technological authority not supported by the researcher’s own reproducible observations and the proofs that followed from them. The scientific method had been born. And yet, it would be almost three centuries before clinical physicians — though overwhelmed by evidence of its error — could bring themselves to forsake therapies based on the last vestiges of the theory of humors.
Like all skilled historians, Arikha is aware that seemingly valid clarifications of the past’s effects on the present may be more suggestive than certain, and sometimes entirely wrong. The thickets are thick, and the misleading alleyways are many. History is a far more difficult enterprise than it may seem to the uninitiated, and it shares several striking perspectives with the enterprise we call science. It is not helped by preconceiving the outcome before the task is undertaken — an appealing thesis must sometimes be abandoned because it cannot be justified by the data — and to admit uncertainty is to come closer to the probability of finding truth.
Arikha contends that while the art of healing may have rid itself of a reliance on Galenic theory to understand and treat disease, the notion of humors continues to exist within modern medical science, in the form of today’s molecular understanding of biological phenomena. Not only that, she claims, but the theories by which we try to explain the factors determining personality, behavior and our “passions and tempers” are, in effect, humoral. It is a tempting proposition, but one for which she provides no persuasive evidence. And it is here that she seems to fall prey to one of the greatest dangers of historical scholarship: its sometime tendency to find lessons where there are, in fact, none to be found.
As Arikha’s narrative comes closer to modern times, she succumbs gradually to the same kinds of leaps of faith, or perhaps a misplaced hopefulness, that led the physicians of earlier times so far astray. It is one thing to perceive that “hormones, enzymes, neurotransmitters, particles and the like” have replaced the four humors as an explanatory mechanism in the popular imagination, and quite another to assert that invoking such factors “is not very different from humoral thinking,” as she does at the outset of her book and again in the pages leading to its conclusion. The mere fact that active substances travel through our bodies in the same way that humors and spiritual essences were thought to does not make them actual or even metaphoric humors. They are real things, discovered by the methods of science; their molecular structure is known and their behavior predictable in a great majority of situations, though much remains to be learned. Theories of their specific actions may differ in small ways, but there is nothing fanciful about them. Because of this, to employ them in explaining behavior, whether biological or psychic, is precisely the opposite of humoral thinking. It is thinking based on reality.
Arikha’s analysis of the Hippocratic history of medicine has brought her a long way, and she does a fine job of interpreting and elucidating the texts and words of earlier eras. It is only when she takes a long step forward into the present that she allows herself to misread the connotations of the newer texts and the newer words. By the time her narrative reaches the late 20th century, the analogies have become tenuous and the conclusions overstretched. Finally, Arikha leaves us with a thesis worthy of Galen himself, who was long on speculation and short on evidence.
Sherwin B. Nuland is a clinical professor of surgery at Yale and the author, most recently, of “Maimonides.”