SCIENCE IN MEDICINE
AUTHOR:
Chukwuma Chinaza Adaobi
DOI: http://doi.org/10.21681/IJMSIR-3702-01366-2021
ESSENTIALS
Science
has always been part of Western medicine, although what counts as scientific
has changed over the centuries, as have the content of medical knowledge, the
tools of medical investigation, and the details of medical treatments. This
brief overview develops a historical typology of medicine since antiquity. It
divides the ‘kinds’ of medicine into five: bedside, library, hospital, social,
and laboratory. These categories are still principal headings in modern health
budgets, but they also have specific historical resonances. (1) Bedside
medicine, developed by the Hippocratic doctors in classical times, has its
modern counterpart in primary care. (2) Library medicine, associated with the
scholastic mentality of the Middle Ages, still surfaces in the problems of
information storage and retrieval in the computer age. (3) Hospital medicine,
central to French medicine of the early 19th century, placed the diagnostic and
therapeutic functions of the modern hospital center stage in care and teaching.
(4) Social medicine is about prevention, both communal and individual, and is
especially visible in our notion of ‘lifestyle’ and its impact on health. (5)
Laboratory medicine has its natural home in the research establishment and is a
critical site for the creation of medical knowledge, setting the standards for
both medical science and scientific medicine. François Magendie (1773–1855) was
probably the first truly ‘modern’ medical scientist: he had little sense of medical
tradition; instead, he sought to establish medicine on new, scientific
foundations.
INTRODUCTION
At At least since the Hippocratics, Western medicine has always aspired to be
scientific. What has changed is not so much the aspirations but what it has
meant to be ‘scientific’. ‘Science is the father of knowledge, but opinion
breeds ignorance’, opined the Hippocratic treatise The Canon, and
Hippocratic practitioners developed an approach to health, disease, and its
treatment based on systematic observation and cumulative experience. Even the
word ‘physic’, whence physician as well as physicist, derives from the Greek
for ‘nature’. Further, Hippocratic medicine was experimental, that word
stemming from the same classical roots which gave us ‘experience’. Words,
however, can be slippery, as philosophers as divergent as Francis Bacon and
Ludwig Wittgenstein has stressed. The science and experiment of the
Hippocratics can still inspire, but they are not our science and experiment.
During the past two or three centuries, an armory of sciences and technologies
has come to underpin medical practice. This essay attempts briefly to describe
these, within the context of distinctive and perennial features of medical
practice, i.e. suffering individuals whose problems and diseases demand
attention.
A
HISTORICAL TYPOLOGY OF WESTERN MEDICINE
The
history of Western medicine can be divided into five ‘kinds’ of medicine:
bedside, library, hospital, social, and laboratory. Each approach to medical
care and knowledge emerged at a particular historical period, but each still
has relevance to us today. Bedside medicine can be equated with the vision of
the Hippocratics, with its emphasis on the individual patient, a tendency
towards holism, and an abiding concern with the patient within his or her own
unique environment. These are some of the reasons why Hippocrates is still claimed as the dominant father figure by both orthodox and alternative
medical practitioners. What can be called ‘library’ medicine dominated in the
Middle Ages, when learned medicine retreated into the universities and scholars
sometimes assumed that everything worth discovering had been uncovered by the
ancients, and everything worth being revealed could be found in the Bible. The
millennium between the sacking of Rome and the discovery of the New World is
often dismissed as a sterile period scientifically, but the physicians of the
period, linguistically erudite and philosophically inclined, would have been surprised to be described as unscientific. They simply
believed that the road to knowledge was through the book.
These
medical men also sometimes engaged with nature, although it is undeniable that
nature rather than words became an increasing source of truth and knowledge
during the Scientific Revolution, a period stretching roughly from just before
Andreas Vesalius (1514–1564) to Isaac Newton (1642–1727). Around 1600, it was
becoming apparent to many that the Greeks had not left behind a complete and
accurate account of the nature of the world, and that scientific knowledge was
cumulative. This ‘Battle of the Books’, the debate over whether the ancients or
the moderns knew more, was decided in favour of the moderns. Many of the
outstanding scientific achievements of the era were in astronomy and physics,
but medicine, both in its theory and its practice, was also affected. The theory has always been easier to change than practice, of course, and it was famously
remarked that William Harvey’s discovery of the circulation of the blood had no
impact on therapeutics. Harvey (1578–1657) also notoriously lamented that his
practice fell off mightily following the discovery, his patients fearing that
he was ‘crack-brained’. The fear that too close an identification with science
was detrimental to patient confidence recurs in medical history and is still
part of the delicate negotiations between the profession and its public, and to
the status of academic medicine.
Within
the discipline of medicine itself there has always been individuals, some of
them, like Thomas Sydenham (1624–1689), eminently successful, who believed that
experimental science had little to offer to patient care. But these artists of medicine could still invoke the authority of Hippocrates, with its older
connotations of knowledge and experience. Sydenham himself did not demur from
his being dubbed ‘the English Hippocrates’. During the early modern period, the
whole spectrum of the sciences—mathematics, physics, chemistry, the life
sciences (not yet called biology)—made their ways into formulations of health
and disease. Astrophysics, iatromathematics, and iatrochemistry all had their
advocates in the 17th and 18th centuries, as approaches to medical theory and
practice.
That
these systems tended to encourage speculation to run ahead of evidence was
recognized at the time, and this was part of the reason why ‘hospital medicine’
had little recourse to those disciplines we now call ‘basic medical sciences’.
The founders of French hospital medicine, Xavier Bichat (1771–1802), J. N.
Corvisart (1755–1821), R. T. H. Laennec (1781–1826), often referred to
chemistry, physiology, and the like as sciences ‘accessory’ to medicine. The
medicine that developed in the Paris hospitals, after the reopening in 1794 of
the medical schools closed by the Revolution a couple of years earlier,
emphasized above all the study of disease in the sick patient. In a sense, this
was Hippocratic medicine writ large, but with some significant differences.
First, the hospital offered the curious doctor a vast arena for observing
disease. The equivalent of a lifetime’s experience of a lone practitioner in
the community could be experienced in a few months of hospital work. Hospitals
offered the possibility of defining disease on the basis of hundreds of cases.
Second, Hippocratic humoralism gradually disappeared as the dominant
explanatory framework of health and disease, replaced by the primacy of the
lesion, located in the solids: the organs and tissues, and by the mid 19th century,
cells. In this new orientation, the disease was literally palpable, its lesions to
be discovered in life by the systematic use of physical examination—Corvisart
rediscovered percussion, Laennec invented the stethoscope—and these findings to
be correlated after death by routine autopsy. French high priests of hospital
medicine brought the diagnosis to a new stage and replaced the older symptom-based
nosologies with a more objective, demonstrable one of lesions. The third
feature of hospital medicine was what Pierre Louis (1787–1872) called the
numerical method, the use of numbers to guide both disease classification and
therapeutic evaluation.
The
philosophy underlying early 19th-century French medicine was most
systematically expounded by one of the many American students who studied in
Paris, Elisha Bartlett, in his Philosophy of Medical Science (1844).
The medical science whose philosophy he chronicled was one of the facts. Bartlett
argued that all systems of medicine, past and present, were speculative, vague,
and useless. Cullen, Brown, Broussais, and Hahnemann were all consigned to the
historical dustbin. The new medicine was one of systematic observation and
collection of facts, which, properly compared and organized, could provide an
objective understanding of the disease and a rational basis for its treatment.
Bartlett’s philosophy was essentially undiluted Baconian inductivism applied to
medicine. Unsurprisingly, he counted Hippocrates as well as Pierre Louis among
his heroes.
One consequence of the lesion-based medicine was the recognition that not much of
what doctors did actually altered the natural history of the disease. Therapeutic
skepticism, or even nihilism, flourished among doctors whose lives were spent,
as Laennec put it, ‘among the dead and dying’. It was less likely to be
expressed among doctors concerned with earning a living treating private, paying patients, but the concern with medicine’s therapeutic
potency also fuelled the movement to prevent disease. The fourth kind of
medicine, social, also flourished in the 18th century. Just as hospitals
existed long before ‘hospital medicine’, so epidemics and preventive measures
were not invented by the public health movement of the 1830s. Nevertheless, the
preventive infrastructures developed partly in response to the cholera
pandemics still exist, although of course much changed. The chief architect of
the British public health movement, Edwin Chadwick (1800–1890), was a lawyer
who thought that, on the whole, doctors were overrated. (He was neither the first
nor the last lawyer to hold that opinion.) He held that filth spread via the
foul smells (miasma) of rotting organic matter caused epidemic diseases. His
solutions were engineering ones, clean water, and efficient waste disposal,
which he argued would leave the world an altogether more pleasant and healthier
place. His ideas were formed during the 1830s and early 1840s, and they
remained more or less fixed for the rest of his long life, which extended well
into the bacteriological age. Nevertheless, Chadwick also invoked science in
his public health reform programme, above all the science of statistical
investigation. His use of statistics can easily be shown to have been naive,
but it was ardent. In his own sphere of inquiry, Chadwick was as much in awe of
the unadorned ‘fact’ as was his contemporary Bartlett. A later generation of
Medical Officers of Health and others concerned with disease prevention (or
containment) would develop new investigative techniques, more sophisticated
statistics, and, especially, new theories of disease causation and transmission.
But the early public health movement was firmly based on the science of its
time.
The
final locus of medicine, the laboratory, was also largely a product of the 19th
century, though of course laboratories (a place where one worked, especially to
mutate gold from lead) had existed for much longer. A leading exponent of the
laboratory, and one of its most thoughtful philosophers, had experienced Paris
hospital medicine as a medical student. Claude Bernard’s Introduction
to the Study of Experimental Medicine (1865) is at once an intriguing
account of his own brilliant career and sophisticated analysis of the
philosophy of experimentation within the life sciences. Hospitals, he argued,
are merely the gateways to medical knowledge, and bedside clinicians can be no
more than natural historians of disease. To understand the causes and
mechanisms of disease, it is necessary to go into the sanctuary of the
laboratory, where experimental conditions can be better controlled. There are
in nature no uncaused causes: determinism is the iron law of the universe,
extending equally to living systems and inorganic ones. However, organisms
present special experimental problems, and it is only through isolating
particular features, and holding other parameters as constant as possible, that
reliability and reproducibility can be achieved.
Bernard
identified three primary branches of experimental medicine: physiology,
pathology, and therapeutics. His own research programme touched all three
pillars: his research on the roles of the liver and pancreas in sugar
metabolism contributed to understanding normal physiology as well as diseases
such as diabetes; his investigations of the sites of action of agents such as
curare and carbon monoxide foreshadowed structural pharmacology and drug
receptor theory; his work on the functions of the sympathetic nerves buttressed
his own more general notion of the constancy of milieu Interieur as
the precondition to vital action (and freedom), a precursor of Walter Cannon’s
concept of homeostasis. Bernard stands supreme as the quintessential advocate
of the laboratory.
