LECTURE 7
The Enlightenment
 The
definition of Enlightenment
 Medical concepts of the Enlightenment
 The development of physiology
 The development of the internal medicine
 The development of surgery
 The Golden Age of Charlatanism
The Enlightement
The Age of Enlightenment or simply The
Enlightenment is a term used to describe a
time in Western philosophy and cultural life
centered upon the eighteenth century, in
which reason was advocated as the primary
source for authority.
The Enlightenment
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One of the medical theories that came into vogue during
the early years of the century was that of:
Georg Ernst Stahl (1660-1734).
He rejected the view that the body was simply a machine
and postulated instead the existence of an anima or sensitive soul
that regulates the body health. Stahl was also a strong advocate
of bloodletting.
A colleague of Stahl’s at the University of Halle was:
Friederich Hoffmann (1660-1742). According to his theory the
entire body was composed of fibres which could dilate or
contract in response to a property called tonus. This in turn was
controlled by a nervous ether emanating from the brain.
The Enlightenment
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William Cullen (1710-1790), professor at Glasgow and
Edinburgh, was influenced by the theory of Hoffmann.
Cullen’s theory of nervous energy as the determinant of the
normal state of the body was further simplified by his pupil
John Brown (1735-1788). He considered excitability to be the
basis of bodily health. Because of this he recommended the
use of stimulants or sedatives to assure the harmonious
balance of stimuli.
Theophile de Bordeu (1722-1776) proposed his own
version. He considered that three important organs of the
body: the stomach, heart and brain elaborated a secretion whose
proper concentration in the blood stream helped to maintain
health. He was the pioneer of endocrinology.
The Enlightenment
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Hermann Boerhaave (1668-1738). Under the influence of
Hermann, the University of Leyden became the leading
medical school of all Europe. He placed the greatest
emphasis on bedside instruction and also insisted that the
student follow a patient’s body to the autopsy to fix clearly in
mind the correlation between lesions and symptoms.
Gerhard van Swieten (1700-1772), a pupil of Boerhaave
was the personal physician of Empress Maria Theresa. He
reorganized the teaching of medicine at the University of
Vienna.
Leopold Auenbrugger (1722-1809). He invented the
diagnosis by percussion of the chest. He also showed how to
plot the outlines of the heart and lungs by percussion.
The Enlightenment
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He recognized diseased areas of lung, repeatedly
confirming his options by postmortem examination. His book
Inventum novum (1761) seems to be the first ever devoted entirely
to diagnosis and the first to be based on an objective sign of
disease.
Alexander Monro (1697-1767) was a Scottish anatomist who
studied under Boerhaave at Leyden. He returned to Edinburgh
and brought its medical school into the front rank.
Albrecht von Haller (1708-1777) was the most notable of all
Boerhaave’s disciples. His many contributions to anatomy
included a correct explanation of hernia. As a physiologist he
demonstrated that while irritability was a property of muscles’
fiber, sensibility was a characteristic of the nerve fiber.
The Enlightenment
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Rene de Reaumur (1683-1757) was the inventor of a thermometer
Lazzaro Spallanzani (1729-1799) was a pioneer in experimental
fertilization
Stephen Hales (1677-1761) demonstrated the dynamics of blood
circulation, stressing the importance of the capillary system and
recording blood pressure with a manometer.
Luigi Galvani (1737-1798) launched the new science of
electrophysiology with his observation that nervous action in
muscle could be included by an electrical charge.
Giovanni Battista Morgagni (1682-1771) was professor of
anatomy at Padua. His masterpiece On the Sites and Causes of Diseases
(1761) contained descriptions of the five hundred cases which he
saw at autopsy.
The Enlightenment
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Xavier Bichat (1771-1802) studied over six hundred corpses
and succeeded in identifying twenty-one different tissues.
John Hunter a Scottish surgeon studied, taught and practiced in
London. He was also regarded as the founder of scientific
geology. His many contributions to medical science included the
first account of inflamation. In operative surgery his great
contribution was a new method of closing off an aneurysm. He
also studied venereal diseases.
In spite of the developments in chemistry, there were few
therapeutic advances in the 18th century. Bleeding and purging
persisted as the mainstays of the practitioner. Syphilis and other
venereal diseases continued to be treated with massive doses of
mercury.
The Enlightenment
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CONCLUSIONS
The most important drug introduced was digitalis, used to
treat a wide variety of illnesses.
In spite of the significant progress in medical science, this
period was also called the Golden Age of charlatanism
The figure of Franz Anton Mesmer (1734-1815) made his
work on animal magnetism the major subject of debate. He
thought hypnosis was a kind of celestial magnetism.
During this period only the rich could be assured of the
services of a qualified doctor of medicine.
Johann Peter Frank (1745-1821), professor at Padua used
statistics to establish the importance of public health.
The Enlightenment
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Smallpox remained the single most deadly killer of the
period
Variolation had been used to prevent the dangerous attacks
of smallpox.
Edward Jenner (1749-1823) invented vaccination. His work
was published in 1798.
The 18th century was not only a period of consolidation and
systematization, but also of considerable new discoveries.