 "Is medicine a science?")
THE LAWS OF MEDICINE FIELD NOTES FROM AN UNCERTAIN SCIENCE
Author: Siddhartha Mukherjee
Publisher: Simon & Schuster/TED
Pages: 120
In the medieval story, a prisoner is sent to jail with just one book, but discovers a cosmos of a thousand books in that single volume. In my recollection, I also read only one book (in 2000) - a slim paperback collection of essays titled The Youngest Science - but I read it as if it were a thousand books. It became one of the most profound influences on my life in medicine. The Youngest Science was subtitled Notes of a Medicine-Watcher and was about a medical residency in another age. Written by the physician, scientist, author, and occasional poet Lewis Thomas, it describes his tenure as a medical resident and intern in the 1930s. In 1937, having graduated from Harvard Medical School, Thomas began his internship at Boston City Hospital. It was a grueling initiation. "Rewarding might be the wrong word for it, for the salary was no money at all," Thomas wrote. "A bedroom, board, and the laundering of one's white uniform were provided by the hospital; the hours of work were all day, every day... There was little need for pocket money because there was no time to spend pocket money." Lewis Thomas entered medicine at one of the most pivotal transitional moments in its history.
We tend to forget that much of "modern medicine" is, in fact, surprisingly modern: before the 1930s, you would be hard-pressed to identify a single medical intervention that had any more than a negligible impact on the course of any illness (surgery, in contrast, could have a transformative effect; think of an appendectomy for appendicitis, or an amputation for gangrene). Nearly every medical intervention could be categorized as one of three P's - placebo, palliation, and plumbing. Placebos were, of course, the most common of drugs - "medicines" that caused their effects by virtue of psychological or psychosomatic reactions in patients (elixirs for weakness and aging, or tonics for depression). Palliative drugs, in contrast, were often genuinely effective; they included morphine, opium, alcohol, and various tinctures, poultices, and balms used to ameliorate symptoms such as itching and pain. The final category - I've loosely labeled it "plumbing" - included laxatives, purgatives, emetics, and enemas used to purge the stomach and intestines of their contents to relieve constipation and, occasionally, to disgorge poisons. These worked, although they were of limited use in most medical cases.
Recognizing the absolute uselessness - and the frank perniciousness - of most nineteenth-century medical interventions, a new generation of doctors had decided to refrain from doing much at all. Instead, luminaries such as William Osler, at Johns Hopkins, had chosen to concentrate on defining, observing, categorizing, and naming diseases, hoping that this would allow future generations to identify bona fide therapeutic interventions. The all-too-human temptation to do something was purposefully stifled. (A doctor's job, Thomas once told an interviewer, "was to make a diagnosis, make a prognosis, give support and care - and not to meddle.") Osler's students didn't meddle with useless medicines; instead, they measured volumes, breaths, weights, and heights; they listened to hearts and lungs, looked at pupils dilating and contracting, abdomens growing and shrinking, neural reflexes appearing and disappearing. It seemed as if the Hippocratic oath - First, do no harm - had been transmuted to First, do nothing.
And yet, doing nothing would have a deeply cleansing effect. By the 1930s, the careful bloodletting of the past had radically altered the discipline; by observing the evolution of diseases, and by constructing models of how diseases occurred and progressed, doctors had begun to lay the foundations of a new kind of medicine.
They had recognized the cardinal features of heart failure - the gradual overloading of the body with fluid and its extrusion into the lungs, the altered sounds of the stretched, overworked heart, or the lethal disruptions of rhythm that followed. Diabetes, they had learned, was a dysfunction of the metabolism of sugar - the body's inability to move sugar from blood into tissues; that in patients with diabetic acidosis, blood became gradually saturated with glucose, yet the tissues were starved of nutrition, like the Mariner who finds water everywhere, but cannot get a drop to drink. Or that streptococcal pneumonias often followed influenza infection; that patients recovering from the flu might suddenly develop relapsing fevers and a hacking, blood-tinged cough; that through the earpiece of a stethoscope, a single lobe of the lung might be found to exhibit the characteristic dull rustling of consolidation -"like a man walking on autumn leaves," as one professor of mine described it.
For Thomas, the astonishing feature of medicine in the 1940s was its ability to use this information to mount genuine therapeutic interventions against diseases based on rational precepts. Once the miraculous recovery from streptococcal infection had been understood as the deployment of a host immunological response, then this, too, suggested a novel therapeutic approach: transferring serum from a convalescent human or animal to a newly infected patient to supply the crucial defensive factors (later found to be antistreptococcal antibodies) to boost the host's immunological response. Here is Thomas describing the treatment for streptococcal pneumonia based on this principle: "The serum was injected, very slowly, by vein. When it worked, it worked within an hour or two. Down came the temperature, and the patient, who might have been moribund a few hours earlier, would be sleeping in good health."
Thomas wrote, "For an intern it was an opening of a new world. We had been raised to be ready for one kind of profession, and we sensed that the profession itself had changed at the moment of our entry... We became convinced, overnight, that nothing lay beyond the reach of the future. Medicine was off and running." It was the birth of what Thomas called the "youngest science."
But the more I read The Youngest Science that year, the more I returned to a fundamental question: Is medicine a science? If, by science, we are referring to the spectacular technological innovations of the past decades, then without doubt medicine qualifies. But technological innovations do not define a science; they merely prove that medicine is scientific. Sciences have laws - statements of truth based on repeated experimental observations that describe some universal or generalizable attributes of nature. Physics is replete with such laws. There are fewer laws in chemistry. Biology is the most lawless of the three basic sciences: there are few rules to begin with, and even fewer rules that are universal.
But does the "youngest science" have laws? It seems like an odd preoccupation now, but I spent much of my medical residency seeking the laws of medicine. The criteria were simple: a "law" had to distill some universal guiding principle of medicine into a statement of truth. The law could not be borrowed from biology or chemistry; it had to be specific to the practice of medicine. Of course, these would not be laws like those of physics or chemistry. If medicine is a science at all, it is a much softer science. There is gravity in medicine, although it cannot be captured by Newton's equations. There is a half-life of grief, even if there is no instrument designed to measure it. The laws of medicine would not be described through equations, constants, or numbers. My search for the laws was not an attempt to codify or reduce the discipline into grand universals. Rather, I imagined them as guiding rules that a young doctor might teach himself as he navigates a profession that seems, at first glance, overwhelmingly unnavigable.
Extracted with permission from Simon & Schuster India, scheduled to be released on October 6, 2015
