Hist 108 Set 4

Paré wrote about the lack of boiling oil for the wounds and the use of his own concoction

"A healing salve made of egg-white, rose-oil, and turpentine ... I slept badly [expecting] I would find the men dead whose wounds I had failed to burn ... To my great surprise, those treated with the salve felt little pain, showed no inflammation or swelling, and had passed the night rather calmly — while the ones on which seething oil had been used lay in high fever with aches, swelling and inflammation around the wound. At this, I resolved never again cruelly to burn poor people who had suffered shot wounds." It was a lucky finding, but Paré was not hidebound. On the contrary, he recognized that the traditional treatment was inferior to his own, cobbled together, method. Turpentine is a powerful organic solvent, and might possibly dissolve bacteria on contact. He was inventive enough to use what he had and was observant and open-minded enough to recognize it was better than what he had been taught.

From the beginning of these lectures in Mesopotamia, we have discussed, or rather danced around, the issue of contagion: disease transmission by direct contact.

A Sumerian healer who forbade the relatives of a sick woman to "drink in the cup where she drinks ... nor sit in the seat where she sits ... no one should sleep in the bed where she sleeps ... [because] this disease is contagious ['catching']." Thucydides noted that doctors and others, during the plague of Athens, caught the disease from the sick. Galen fled Rome when the Antonine Plague was approaching, fearful of contracting it. He realized certain epidemic diseases could be contracted from contact with sick individuals. During the Black Death, many thought the best course was to get away from people: 'flee far and fast.'

Endemic diseases

A disease becomes endemic in a population when it has infected a large percentage of the people (killing or immunizing them). It then becomes present only at a low, sporadic level. If it remains at a low level, it usually does not cause large die-offs. However, it may mutate or find new, non-immune victims, flare up and become epidemic. Endemic diseases are often childhood diseases such as measles to which most adults have become immune through childhood infection or immunization. Before measles vaccine, most Americans caught measles and acquired immunity in childhood and never contracted the disease again. Thus, measles did not typically affect adults in whom it is more dangerous than it is in children. Some authorities also stress the size of the population and argue that measles requires a minimum of 500,000 people to remain endemic; otherwise it burns itself out. Smallpox in 18th-century Europe was probably endemic and responsible for numerous cases of disease, usually among younger people without immunity. It killed 5-20% of its victims and disfigured many survivors; it was not an insignificant disease and was often called the 'speckled monster.'

Paracelsus in Basel

After accepting the job of civic physician in Basel, Paracelsus immediately alienated the local medical faculty by lecturing in the vernacular German rather than the scholarly Latin, publicly burning Avicenna's Canon and several works of Galen, and sneering at university teaching, saying: the more learned, the more perverted.

Galen's physiology

Although Galen tried to hold a viewpoint in between the the empiricists and the dogmatists, he professed a greater affinity for the empirical evidence of dissection. Nevertheless, he sometimes favored the dogmatists' theories more than he did the empiricists' observations. Moreover, Galen's cardiac physiology was not built on accurate, empirical observations: there are no pores in the IVS; there is no air in the pulmonary vein; the vena cava does not originate in the liver; and blood does not flow in 2 directions out of the liver in the vena cava. In fact, Galen's interpretation of the evidence of dissection was sometimes fatally biased by his theory; he convinced himself that he 'saw' what he needed to see in order to confirm his theoretical system of physiology: pores in the cardiac septum and the rete mirabile.

Ambrose Pare

Ambrose Paré (1510-1590 CE) was a 16th-c. French barber-surgeon who was highly-trained, resourceful, observant, innovative, and remarkably humble about his successes. When one of his patients did well, Paré would decline the credit saying, "I only bandaged him — God healed him." Though not an elite, educated surgeon, Paré had an intuitive feel for his work that made him a model surgeon. He was open-minded and always happy to learn from anyone. Moreover, the dissemination of medical and surgical knowledge was rapidly being facilitated by the printing of treatises and textbooks in the vernacular languages as well as Latin. Paré, himself, would write important surgical texts that were "reprinted many times and translated into Latin, German, English, Dutch, and Japanese." Paré was trained in the standard care of wounds, so his first battlefield experience involved the use of cautery with a red-hot iron to stop bleeding and the boiling oil to counter the poison. Fortunately for all concerned, his supply of oil ran out. Forced to improvise, he substituted a concoction of his own, and he also began to use suture ligatures instead of the red-hot cautery. Necessity, of course, is the mother of invention, and so it was with Paré, and he was astute enough to realize it. Moreover, he was willing to go against the current of accepted medical wisdom and decide for himself that "the gunpowder and shot were not, after all, poisonous."

Pulmonary transit

Andrea Cesalpino, Michael Servetus, and Realdo Columbo had begun to understand the pulmonary transit, but no one seemed to suspect the existence of a systemic circulation. Columbo (1515-1559 CE) demonstrated the pulmonary transit (or pulmonary circulation) by vivisecting animals, finding no air in the pulmonary vein - only blood returning to the heart. Moreover, Vesalius' 1543 publication of De fabrica had challenged several of Galen's anatomical conclusions, especially the existence of pores in the IVS of the heart. Similarly, Hieronymous Fabricius (1533-1619 CE) had studied the valves in the veins, but it was Harvey who showed that these valves prevented the flow of venous blood away from the heart challenging Galen's entire notion of a centrifugal flow of blood flow in veins. Fabricius did not discover the valves in the veins, but he was the first to ponder their purpose. He believed the valves ensured even distribution of blood to all limbs and tissues. Fabricius (Harvey's anatomy professor), believed Vesalius overlooked this because he (Vesalius) valued descriptive anatomy over physiology and understanding the purpose of anatomical parts. Still, it seems likely that Fabricius, himself, was unable to properly understand the valves because of his own Galenic bias that venous blood moved away from the heart.

Antonie van Leeuwenhoek and microscopy

Antonie van Leeuwenhoek (1632-1723 CE) made significant improvements in microscopes that he kept secret. He was able to see much smaller objects, including single-cell organisms and bacteria, that others could not see. His drawings of microscopic organisms were published by the Royal Society, and the concept of tiny, invisible organisms (animalcules) became more accepted. Microscopy would become instrumental to the creation of new medical knowledge. Providing entry to an unknown realm of living things, it became crucial to the acceptance of new theories taking shape. It became ever more useful as it was improved during the 19th c. Microscopy allowed scientists to see the natural world differently, to literally see things previously unseen, "by the help of microscopes, there is nothing so small, as to escape our inquiry; hence there is a new visible World discovered to the understanding." Microscopy was an evolutionary force within biology, magnifying scientists' powers of observation and promoting the natural selection of competing theories. Very gradually, Humoral Theory and miasma theory were beginning to lose traction.

Blue Mass

Blue Mass was the name of a common mercury compound used until the 19th century to treat tuberculosis, constipation, toothache and labor pains. The usual dose of Blue Mass was 100 times the daily limit now accepted as safe for mercury. Rush was an aggressive physician and is usually credited with (or blamed for) introducing 'heroic medicine' to colonial America.

Antonie van Leeuwenhoek

Antonie van Leeuwenhoek, was able to see bacteria in the 1670s using microscopes of his own making, but they were simple, single-lens microscopes. Using only only a single lens, which he ground, van Leeuwenhoek was able to keep the image relatively sharp as he increased the magnification. However, he was the only microscopist able to appreciate many of these startling findings, because no one else could match his lens crafting skills. Still, while van Leeuwenhoek probably saw bacteria, he did not see 'bacteria' in the way we see them today, because today the term, 'bacteria,' has implications it did not have in the 17th c. Not until the work of Louis Pasteur and Robert Koch in the mid-19th century would bacteria be associated with disease.

Medeival Warm Period and Little Ice Age

Around 950 CE, Europe entered a new climate era, the Medieval Warm Period, lasting until about 1250-1300 CE. It was a time of unseasonably warm weather, correlating with and likely causing a period of sustained agricultural surpluses and population growth. This warm era allowed the Norsemen to colonize Greenland and North American. It was followed, though, by the so-called Little Ice Age that lasted from about 1300 to 1850 CE. In the early 14th c., this cold weather caused widespread crop failures in Europe, the great famine of 1315-1317, followed by the second pandemic of bubonic plague.

More on Leopold Auenbrugger

As we shall see, in the same year, 1761, Leopold Auenbrugger (1722-1809 CE) published a small book outlining his new technique of chest percussion to examine the chest. Both Auenbrugger's work and De Sedibus would stimulate the the early 19th-c. physicians of what is called the Paris School. Percussion of the chest would reveal antemortem findings in the chest that would later be correlated with the pathological findings at autopsy. Indeed, Morgagni's collection of 700 cases "was soon dwarfed by the Paris school, whose clinicians ... could accumulate in a couple of years as many post-mortem records as Morgagni collected during his long life."

Marcello Malpighi

At about the same time (1661 CE), Marcello Malpighi(1628-1694 CE) used a microscope to examine the lung tissue of a frog. He identified the capillary vessels, microscopic vessels connecting the arterial system to the venous system. Arguing from analogy, he correctly inferred that the same system existed in humans and was where blood began to return to the heart. It is in this capillary connection between arteries and veins that blood absorbs oxygen in the lungs and releases oxygen to the tissues of other organs. When we discuss the work of William Harvey (1578-1657 CE), done before Malpighi's discovery, we will see that Harvey believed these connections must exist, but he could not see them or prove their existence. So, Malpighi could see capillaries and Hooke could make out 'cells' and draw beautiful images of lice and fleas, butthey could not visualize microorganisms, unicellular organisms, or bacteria using the compound microscope in the 17th century.

Athanasius Kircher

Athanasius Kircher (1602-1680 CE), a Jesuit priest, was probably the first person to use a microscope to examine patients' blood. During a 1656 plague outbreak in Rome, he used an early microscope to study the blood of a plague victim. He thought he saw microscopic organisms moving about in the blood. He called these animalcules. While he probably did not see the actual pathogen, he and others believed he had. Even so, his work failed to convince more than a small handful of other scholars. Because Kircher was almost certainly familiar with Fracastoro's ideas of seeds of disease. He was likely primed to 'see' such seeds, an example of theory-laden observation. Whether he saw bacteria or not, his 1658 publication Scrutinium Physico-Medicum (Physico-Medical Examination), added to the theory of external, infectious causation in the developing dialogue about the disease causation and kept the idea circulating among scholars.

Morgagni and organs involved in disease

Autopsies had been done in the Medieval Period to determine the cause of death for legal reasons. However, Morgagni was the first to compile a large series of morbid anatomy cases that allowed him to identify the organs involved in different diseases and to begin to describe the natural history of diseases. Morgagni was a committed empiricist, and Bynum suggests that his use of the Hippocratic-like case histories brought together the classical, holistic approach and the increasingly modern scientific methods. Sydenham had introduced the focus on specific symptom complexes which Morgagni correlated with the pathological findings. The Paris School would then correlate both with the signs found on physical examination (chest percussion and auscultation). Moreover, Morgagni's correlation of diseases with specific organs also supported the concept of disease specificity and eroded much of the remaining confidence in humoral theory. His success in identifying the characteristic aspects of diseases within specific organ systems increased the need for more and better knowledge of normal human anatomy, ensuring the importance of anatomical dissection to medical education.

Vesalius, Galen, and the heart

Being wrong about the rete mirabile was bad. Worse was Vesalius' conclusion that Galen's notion of the pores (openings) in the interventricular septum of the heart was also incorrect. These were the openings that Galen believed allowed blood to pass directly from the right side of the heart to the left, and Vesalius concluded that these pores did not exist. Disproving the movement of the blood from the right side of the heart to the left through the septum would help Realdo Columbo (1515-1559) develop the idea of the pulmonary transit of the blood and it would prove to be "an important step in conceiving of a systemic blood circulation" almost 100 years later by William Harvey. Still, even finding significant errors, Vesalius could not reject Galen's authority. It was too well established. Vesalius did not oppose "the traditional tripartite division of physiologic function (venous, centered on the liver, arterial, centered on the heart, and sensory/motor, centered on the brain) ... For all their radical rhetoric, Vesalius' generation shored up ancient medicine and philosophy even as they exposed its factual errors."

Berengario

Berengario da Carpi (1460-1530 CE). Berengario not only dissected before Vesalius but also "argued in his 1522 [Introduction to Anatomy] that observation was the sole path to truth."True to his own faith in empirical observation, he denied "the existence in humans of Galen's rete mirabile," because he could not find it; he could not observe it. Vesalius is usually credited with realizing that Galen had seen the rete mirabile in animals and wrongly assumed it existed in humans. In fact, however, it was Berengario's great triumph.

Bonomo rejeted Galen

Bonomo explicitly rejected Galenic humoral theory, denying that "the Melancholy Humour of Galen" was a cause of this disease, the cause being "no other than the continual biting of these Animalcules in the Skin." So, Bonomo was the first to clearly describe a specific, tiny pathogen causing a specific disease, establishing the concept of disease specificity: a disease is a specific entity with a specific cause. At the same time, he substantiated the concept of tiny, living, external organisms entering the body to cause disease. Furthermore, his repudiation of Galenic humoral theory in scabies shows that he was aware of the importance of his theory. He was consciously constructing new knowledge with the potential to replace humoral theory using a totally new understanding of disease causation. Because of its radical nature, his new theory did not convince many. Skepticism, though, was understandable as was reluctance to reject a longstanding paradigm (theory), a paradigm that had adequately explained the etiology and physiology of human diseases for centuries. Few observers would have been inclined to suddenly abandon an older, respected, and useful paradigm in order to embrace a newer one, especially those not acquainted with microscopy and not having seen any actual animalcules.

Challenges to understanding microbes

But why did the compound microscope not produce important, even revolutionary, findings in its first decades as the telescope did? There was an unknown world of microorganisms waiting to be identified, but a problem slowed the discoveries: the image distortion caused by spherical and chromatic aberration. These two difficulties made it impossible to obtain clear, high-magnification images with 17th and 18th century versions of the compound microscope. The cell nucleus, for example, was not plainly visible until Robert Brown described it in 1831. Not until well into the 19th c. did the image quality of the compound microscope exceed that of the simpler, single-lens design, at least in the hands of van Leeuwenhoek. From the mid-17th c. to the mid-19th-c., there was no direct connection between the visualization of bacteria under the microscope and disease causation. Few scholars, if any, thought that these were Fracastoro's 'seeds of disease' or that these were the 'animalcules' that Kircher believed he had seen in the blood of plague victims. Part of scholars' reluctance to immediately embrace and accept any theory about so-called 'seeds of disease' had been the lack of empirical evidence. Now, there was good evidence of a world of microscopic organisms that no human had ever seen before, but the crucial connection between the theories of Fracastoro and Kircher and the microscopic findings of van Leeuwenhoek was not made until the 19th century.

German chemical industry produces new treatment

By 1900, the German chemical industry was producing huge quantities of synthetic dyes. Ehrlich knew that certain dyes had an affinity for certain bacteria and believed he might find a dye or other compound that would bind to a bacterium and damage it - preferably destroy it completely, without injuring the patient. Ehrlich had his assistant screen hundreds of newly synthesized drugs coming out of German chemical labs, searching for one that killed the organism but spared the host. An initially promising chemical did kill the bacterium, but it also blinded patients and was discarded. However, in 1909, arsphenamine, and it turned out to be the one. Marketed in 1910 as Compound 606, it was also known as Salvarsan. By this time (1910), the humoral theory had been discarded and disease specificity was widely understood and accepted. However, syphilis had always been a shameful disease with overtones of immorality and sexual promiscuity. With the new treatment, though, it became more "a medical rather than a moral problem." There are obvious parallels with the late 20th c. origins of HIV. Ultimately, antibiotics such as penicillin would cure syphilis reliably and safely.

Emperor Justinian I

By 540 CE, the Western Roman Empire had dissolved into a handful of European kingdoms, and the Eastern Roman Empire (or Byzantine Empire) was still intact, ruled by the Emperor Justinian I. He wanted to reunite the two halves of the older Roman Empire and to defeat the Persian Empire (AKA the Sassanian Empire). Islam did not yet exist. Justinian's efforts were severely compromised by two completely unexpected events. The first was a short period of very severe cold weather known as the extreme weather events of 535-536 that decimated agricultural supplies and led to widespread famine. The second was the Plague of Justinian, an epidemic of bubonic plague that arrived in Egypt in 541 CE and proceeded to ravage Justinian's empire and most of the surrounding areas.

Calomel

Calomel was another popular mercury compound that was touted by Benjamin Rush and given Meriwether Lewis to treat the members of the Corps of Discovery.

Human dissection at the time and Vesalius

Despite Berengario's work, dissection had not been common in the 14th and 15th c. because a "dissected cadaver [added] little to the information available from other sources." The other sources, of course, were the texts being debated using the scholastic methods of the medieval universities, and the debates were purely theoretical without recourse to dissection to 'see for oneself,' or autopsia. However, by 1525, most of Galen's writings were available to western scholars and he had always emphasized the need for dissection (though he had only dissected apes and pigs). Still, Galen stressed the need to return to the dissecting table to answer questions. So, that was what Vesalius did, and that was where he began to discover discrepancies in Galen's work. Vesalius was a superb anatomist, carrying out the dissections himself and comparing what he found with what Galen wrote. This was different than the usual medieval method of dissection done by a barber surgeon with a professor reading from a manual, though a few late medieval scholars such as Guy de Chauliac and Mondino de Luzzi had performed their own dissections. Vesalius learned that Galen had actually only dissected Barbary apes and other animals, not humans.

Setbacks to understanding circulation

However, there were no known connections between the arteries and the veins. The capillary network was too small to be seen in Harvey's day with the unimproved compound microscope. Recall that the capillary system was not visualized until 1661 when Malpighi discovered it. In another simple experiment, Harvey stopped the arterial supply of blood to the arm of an assistant with a very tight tourniquet and showed that the veins did not change. However, with the tourniquet loose enough to allow the arterial supply of blood to the arm but still tight enough to compress the superficial veins, the veins were seen to swell dramatically indicating that somehow the blood was passing from the arteries to the veins. Though, Harvey could not see the capillaries connecting the arteries to the veins, he could infer their existence with this demonstration.

Paracelsus in medical history

Evaluating his place in medical history is complicated by his persistent mysticism and belief in "the workings of invisible powers as spiritual intercessors between God and man in an enchanted cosmos and his creed always involved mystical and esoteric doctrines quite alien to today's science. However, he pioneered the study of chemical theories of health and disease. Too, his belief in learning from nature was an empirical stance contrary to the rationalism and theorizing of the university professors and learned physicians, whom he insulted at every opportunity. The always reliable, Roy Porter, argues also that Paracelsus significance lay in pioneering a natural philosophy based on chemical principles. Paracelsus criticized the techniques of uroscopy, such as determining color, clarity, and odor. He advocated alchemical techniques such as distillation, heating, and precipitation. He did not see himself improving a known technology (uroscopy) by the addition of new analytic techniques. If he had, he might have convinced some of the value of his contribution. He ridiculed learned physicians and dismissed the experience and scholarship of others, gaining no friends or allies who could have helped him develop an early form of urinalysis. In his lifetime, he created no useful knowledge, only bombast. Only generations later would some physicians and scholars take up his criticisms of Galenism and promote the importance of chemical tests and treatments.

Galen's influence remains

Even though Galen's influence was beginning to decrease during the 17th century, it was a very slow process. There was no other, well-accepted theoretical system to take the place of humoralism and guide physicians' understanding of disease or their treatment of patients. Modern philosophers of science note that it is difficult, or impossible, for scientists to abandon a leading theory if there is not another, competing theory available to explain observed phenomena.

Post analysis of Hippocrates and Galen as well as the idea of the learned physician

Even though we know very little about Hippocrates, his name conjures up his belief that physicians should learn about the patient's disease at the bedside through close observation of all aspects of the patient's lifestyle, diet, disease, and treatment. Hippocrates was an empiricist who used the senses (sight, sound, touch, and smell) to evaluate patients and diseases. He was not a strict rationalist aiming to reason his way to an understanding of disease. While arguing that he favored empiricism, Galen was both rationalist and empiricist, and some of Hippocrates' wisdom was obscured by Galen's penchant for speculative reasoning in place of a more empirical approach to the creation of new knowledge. The learned physicians of Medieval Europe were haughty rationalists who looked down on the scorned 'empirics.' Learned physicians put so little value on empirical evidence, they were even able to diagnosis and treat patients by mail.

Harvey and circulation

Fabricius was partly correct, but he did not realize the valves actually facilitated venous blood flow towards the heart and prevented the flow of venous blood away from the heart. Harvey would later prove this by inserting a probe into veins and demonstrating the way the valve prevented free passage of the probe away from the core of the body to the periphery. Paracelsus, of course, had challenged essentially all of Galenic knowledge, but it is unclear how much influence he had on Harvey or on the general intellectual climate of Harvey's time. Harvey often vivisected frogs and snakes. Their heartbeat is slower than mammals, making it easier to see and decode the motions of the hearts chambers. Thus, Harvey was able first to confirm Columbo's description of the pulmonary transit. Harvey's great work was De Motu Cordis et Sanguines (On the Motion of the Heart and Blood, or De Motu Cordis - 1628). His crucial experiments were simple, elegant, and convincing. He calculated the volume of blood ejected from the left side of the human heart: about 2 ounces/beat. An average heartbeat is about 70 beats per minute, meaning about 140 ounces ejected every minute or about 525 pounds of blood per hour. It was simply inconceivable that a person could make this much blood in a day. It must somehow pass from the arteries to the veins and then circulate back to the heart.

Despite the horrific mortality, the Black Death had some beneficial consequences for medieval European culture

First, it sparked public health efforts to mitigate its worst effects. These could be invoked during subsequent epidemics and better developed over time to improve outcomes. Second, the tremendous population loss improved the lives of the surviving lower classes by reducing financial inequality. As agricultural workers died, there was insufficient labor left to till the land. At the same time, more land became available when owners died. Thus, labor became scarce and more valuable, while land became available and less valuable. Third, rural peasants gained more geographic mobility. As a landowner's peasants died, he/she welcomed other peasants moving in looking for better opportunities and better pay. Fourth, the increasing cost of labor led to the development of labor saving technologies that could take the place of costly human labor. Fifth, the urban lower classes gained higher wages and took advantage of employment opportunities that opened when others died. They gained upward social mobility, which inspired 'sumptuary laws' preventing them from wearing upper-class clothing, and assuming upper-class airs. These laws were designed to keep the aspirations of the lower classes in check and maintain the prevailing social hierarchies.

Despite a growing acceptance of disease specificity, Humoral Theory could not be rejected outright for several reasons.

First, it was ingrained in physicians' consciousness; they had been steeped in it through their educations. Second, it had successfully explained disease causation and treatment for centuries; was it possible that everyone had been wrong for a thousand years?Finally, and very importantly, there was no competing theory available with which to replace humoralism.

Cell theory

First, living organisms are composed of cells. Second, the cell is the most basic component of living organisms. Third, cells arise from other cells. (third portion was added by Rudolf Virchow in 1865)

Symptoms and types of bubonic plague

Humans become infected when bitten by the flea, causing the bubonic plague with the classic buboes hugely swollen lymph nodes in the groin and armpits. In some cases, the bacteria find their way to the lungs, cause a pneumonia, and can be coughed or sneezed onto other humans. When the bacteria are inhaled into the lungs after airborne transmission (think Covid-19), they may cause an even more deadly pneumonic form that is transmitted from human to human through aerosolized airborne droplets. In some cases, patients develop an overwhelming infection within the blood (the septicemic form) that is rapidly distributed to the major organs (liver, lungs, kidneys, etc.) and causes cardiovascular collapse and very rapid death.

Galen's anatomical and physiological explanations of the heart, liver, and blood were different than ours today

Food was absorbed from the gut and taken to the liver in the portal vein where it was turned into blood. From the liver blood went out through the vena cava. Some went to various tissues and some to the right side of the heart, from there some blood went to the lungs and some went through pores in the interventricular septum. Galen could not see these pores; but, he (incorrectly) reasoned they must be there (for his system to work), even if invisible to him. From the lungs, vital pneuma traveled through the pulmonary vein to the left side of the heart and mixed with the blood coming in through the pores in the interventricular septum. The process of mixing created the arterial blood that was lighter and redder because it contained pneuma and innate heat, supplied by the heart itself. The venous blood from the liver and the arterial blood from the left side of the heart were distributed to, and absorbed by, the various tissues of the body. Both the constant production of new blood in the liver and its essentially complete absorption by the tissues of the body (after being distributed by both the veins and the arteries) was a continuous process. In Galen's physiology there was no notion of a 'circulatory system' in which the blood circulated continuously from the left side of the heart to the body, through the capillaries, and into the veins to return to the right side of the heart, then to the lungs and then back to the left side of the heart to begin the circulatory journey all over again. Instead, blood was constantly being absorbed and replenished by new blood from the liver.

Plague Suit

From a practical standpoint, the theory of seeds entering the body suggested ways of preventing disease, and the suit worn by a medico della peste was probably an effective barrier to many different types of 'seeds' including fleas carrying Yersinia pestis. The beak-like face covering stuffed with sweet-smelling herbs might even have filtered out aerosolized droplets, or fomites, coughed or sneezed by patients. However the suit was invented by French physician to the royal court, (Charles de Lorme) in the 17th c. Hence, it was not invented until well after the end of the medieval era, even though it is often referred to as the medieval plague suit.

Why was Galen not rejected easily?

Galen and his theory of physiology were simply too firmly ingrained in the European understanding of medicine, health, and disease to be rejected outright. The rejection of a useful paradigm does not normally occur quickly, and it usually requires the immediate availability of a new paradigm to replace the older, rejected one. There was no new paradigm waiting in the wings to replace Galen's physiology, Humoral Theory, or medieval Galenism. These were firmly established and, despite Paracelsus ideas, no new theory had been elaborated to challenge them or to replace them. Still, there was a new willingness to question at least some aspects of Galen's work. It was not quite revolutionary, but it did constitute the early stages of an evolutionary change. Along with the ideas of Fracastoro, Kircher, and Paracelsus, there was "something in the air," the beginning of a new intellectual milieu. It was not yet new knowledge or theory, but there were stirrings of disagreement with Galenic and Hippocratic thought.

Vesalius, Galen, and the rete mirabelle

Galen had found the rete mirabile at the base of the brain in both apes and other animals and naturally, though incorrectly, assumed that it was also present in humans. For Galen, the rete mirabile was an essential structure. In his physiology, it transformed vital pneuma into psychic pneuma, which was as critical to the functioning of the brain. Vesalius easily found the rete mirabile in cows, so he knew what it looked like and where it should be, but he could not find it in humans. His confidence that Galen had been wrong was probably also bolstered by the fact that Berengario da Carpi had also pointed out that it did not exist in humans. Being wrong about the rete mirabile was bad. Worse was Vesalius' conclusion that Galen's notion of the pores (openings) in the interventricular septum of the heart was also incorrect.

Girolamo Fracastoro

Girolamo Fracastoro (1476-1553), a Venetian physician, built on the ideas of Galen and Varro about 'seeds of disease' to explain infection and contagion. His thinking was impelled by the appearance, and horrendous nature, of syphilis and its venereal spread. Clearly, syphilis was not a miasmatic disease, and it did not seem to be related to humoral balance or imbalance. It was certainly contagious under the right circumstances, being spread from one person to another through intimate, sexual contact. In 1546, Fracastoro published On Contagion: Contagious Diseases and their Cure (known as De contagione). He defined contagion as, "an infection that passes from one thing to another" and introduced the concept of fomites. Fomites, wrote Fracastoro, are inanimate objects such as "clothes, wooden objects, and things of that sort, which though not themselves corrupted can, nevertheless, preserve the original germs of the contagion and infect by means of these." Fomites include flies, hair, shed skin, or aerosolized droplets. Mosquitoes, ticks, and fleas might be considered a special category of fomites, though they are usually called disease vectors. Fracastoro's concepts of seeds of disease and fomites were important from both a theoretical and a practical aspect, and the term (and the concept) fomite is still used today, 475 years later. His theory of disease causation with these 'seeds' being something outside the body, which entered the body to cause disease was conceptually different from humoral theory in which disease was due to an imbalance of humors internal to the body.

Paracelsus belief on disease

He believed that disease "was the result of derangements in the chemical functions of the body rather than a humoral imbalance." Rejecting humoral theory, he insisted that each disease was a specific entity, instead of a non-specific disturbance of humoral equilibrium.

Paracelsus rejects Galenism

He probably received a conventional medical degree but soon broke with the orthodox, learned medicine that was based on Galenism. He rejected Galen's works and theories, including humoralism. He also rejected Islamic scholars such as Avicenna. He rejected learned medicine's reliance on medical texts and received wisdom. Instead, he preached that physicians should listen to common people with common medical knowledge obtained from reading what he called 'the book of nature.' (essentially, empirical observation). eRejecting the four humors, Paracelsus concentrated on chemical substances such as Sulphur, salt, and mercury which he believed caused disease and also could treat diseases.

Nicolaus Copernicus and Andreas Vesalius and their books

In 1543, a century after the fall of Constantinople, two remarkable books were written and published, one by Nicolaus Copernicus the other by Andreas Vesalius (1514-1564). Both were instrumental in overturning older theories handed down for centuries as received wisdom. Copernicus' On the Revolutions of the Celestial Spheres (commonly known as De rev — short for Derevolutionibus) put forward his heliocentric theory of the universe, challenging the Ptolemaic system that had dominated astronomical thinking and calculations for centuries. Vesalius published, On the Fabric of the Human Body (De fabrica ) a compendium of anatomical drawings of the human body, in which he challenged some of Galen's findings. But Galen had been the supreme authority to whom centuries of physicians, Christian and Muslim, had turned for the answer to their questions. Galen's work was not a source of information or an answer; it had always been the the source and the answer. Finding errors in Galen's work might make one question whether there were other errors, and if so, how many, and how seriously would they undermine the truth of ancient authors?

Marcello Malpighi

In 1660/61 (32 years later), Marcello Malpighi (1628-1694 CE), using a microscope similar to that of Robert Hooke, would identify the capillary vessels in the lung tissue of a frog. •Malpighi correctly reasoned by analogy that this system must also exist in humans: it must be the area of the vascular system where the blood completed its outward journey and began to return to the heart to complete the systemic circulation.

Joseph Jackson Lister

In England, Joseph Jackson Lister, a brilliant optician and lens crafter was able to make significant improvements in both spherical and chromatic aberration and improve the image quality of the compound microscope during the 1830s and 40s. His other notable achievement was siring the pioneer of antisepsis, Joseph Lister, whom we will meet in a later lecture. The work of the elder Lister and others allowed Theodor Schwann (1810-1882 CE) - and others - to visualize living cells and their nuclei clearly enough to elaborate the cell theory in 1838.

Smallpox overview

In fact, however, prevention began to occur at the end of the 18th century when Edward Jenner introduced vaccination against smallpox, the "one eighteenth-century improvement in practical medicine which decisively saved lives." The first reliable description of smallpox was made by a Chinese physician in about 300 CE, but it may have begun infecting humans during the Neolithic Period. Some scholars believe that the mummy of Ramses V (d. 1145 BCE) reveals evidence of smallpox scars, and there is evidence that the smallpox virus has mutated over the centuries. One strain may have caused the Antonine Plague known to Galen in 166 CE. Recall that Rhazes was the first physician to properly distinguish it from measles during the 10th century, when smallpox was probably less lethal than it would later become among 17th and 18th c. Europeans.

Paracelsus parallels Martin Luther

In many ways, Paracelsus' life and thought paralleled that of his contemporary, Martin Luther. Both were radical reformers, going back to the legitimate roots of their disciplines. Bynum argues that, "Paracelsus was obviously influenced by the intellectual and emotional ferment that Martin Luther's movement formally inaugurated." Luther believed that individuals could, themselves, learn directly from the Bible; people did not need, and should not be subjected to, the meddling interpretations of the Pope and clergy. Paracelsus, too, believed physicians and patients should learn from 'the book of nature' and dispense with the teachings of Galen and the meddlesome trappings of learned medicine. Instead of medical texts, he believed doctors should learn at the bedside from patients and their diseases. He was prescribing an empiricist (Hippocratic) method of learning from experience and observation at the bedside, not scholastic disputation about ancient texts. His "commitment to the discovery of truth through observation and experimentation ... [inspired] the new medicine emerging in the 'scientific revolution'."

Reintroduction of human dissection

In previous lectures, we discussed the rediscovery of anatomical dissection during the medieval period: pigs in 12th-c. Salerno and human autopsy for legal purposes in the late 13th century. This was followed by the introduction of human dissection, first at Bologna and Montpellier, to improve physicians' knowledge of the body. Recall that, Mondino de Luzzi was instrumental in establishing public dissection as a teaching practice in the first decades of the 14th c. As an expert anatomist and dissector, he carried out the dissections himself, even writing a manual to guide others. So, Vesalius did not exactly revive anatomical dissection. He was not the first European to undertake anatomical dissection in the 1500 years since Herophilus or Galen. Instead, he was building on the work of others, such as Mondino and Berengario da Carpi (1460-1530 CE).

Plague of Justinian impact on society

In sum, the devastating effects of the Plague of Justinian had a decisive effect on the historical events of late antiquity, helping to determine the fate of three empires, bringing the period of late antiquity to an end, and ushering in the Early Medieval Period. At least, that was the prevailing interpretation of the Plague of Justinian until recently. It is being challenged by two young scholars (Mordechai and Eisenberg), who maintain that the so-called devastation in the wake of the plague was much less significant. They believe the Plague of Justinian was not severe enough to cause these historical changes. This is an interesting, ongoing controversy in historical research that highlights the way scholars interpret evidence and dispute with one another. The uncertainty itself is enlightening. The first pandemic continued after the initial wave (Plague of Justinian), returning in epidemic waves for 200 years, disappearing from Europe (and the Mediterranean) about 750 CE.

Thomas Sydenham

In the 17th c., however, we meet a true intellectual reincarnation of Hippocrates: Thomas Sydenham (1624-1689 CE). Influenced by the English philosopher, John Locke, (1632-1704), Sydenham was an empiricist in the Hippocratic mold. For Sydenham, the specificity of cinchona bark as a cure for only a single disease entity made it unique among drug treatments. In his mind, it also created strong support for a general theory of disease specificity. Likewise, he argued that the bubonic plague, traveling from town to town (as it was clearly observed to do), suggested it was an external entity, contrary to the humoral theory of disease being an internal imbalance of humors. So, even though he distrusted aggressive treatments, such as copious bleeding, Sydenham could not completely reject humoralism or bloodletting because there was nothing else with which to replace them.

Traditional narrative of second plague

In the early 14th c., this cold weather caused widespread crop failures in Europe, the great famine of 1315-1317, followed by the second pandemic of bubonic plague. The initial wave was the Black Death, (1347-1351). "Black Death" is a 19th-c. term, and 14th-c. people who lived through it called it the 'Great Mortality' or the 'Pestilence.' The traditional narrative posits its origin in the Central Asian Steppes during the first decades of the 14th c. Mongol horsemen or trade caravans probably carried it westward toward the Black Sea where it infected the troops of a Khan of the Golden Horde named Jani Beg, besieging the city of Kaffa (early Italy). The traditional narrative (now being revised) says that Jani Beg's troops catapulted the dead bodies of their own troops who died of the plague into the city, infecting the Genoese traders who lived there. In the early 14th c., this cold weather caused widespread crop failures in Europe, the great famine of 1315-1317, followed by the second pandemic of bubonic plague. The initial wave was the Black Death, (1347-1351). "Black Death" is a 19th-c. term, and 14th-c. people who lived through it called it the 'Great Mortality' or the 'Pestilence.' The traditional narrative posits its origin in the Central Asian Steppes during the first decades of the 14th c. Mongol horsemen or trade caravans probably carried it westward toward the Black Sea where it infected the troops of a Khan of the Golden Horde named Jani Beg, besieging the city of Kaffa. The traditional narrative (now being revised) says that Jani Beg's troops catapulted the dead bodies of their own troops who died of the plague into the city, infecting the Genoese traders who lived there. These Genoese (Italian) merchants then sailed for home (Italian City-States) carrying the disease with them and initiating the European phase of the Black Death. The crux of this story: from the Asian Steppe, the plague reached the Black Sea and was then carried in trading ships around the Mediterranean basin and with grain shipments into Europe. The plague reached Italy in 1347 and spread throughout Europe, the Middle East, and N. Africa. It even reached Iceland. Modern historical research is widening the usual Eurocentrism by illuminating the plague's devastation further afield in Africa and the Indian Ocean. The devastation was dramatic, and difficult to overestimate. Europe's population in 1347 was ~70 million, the pandemic spread rapidly and killed about half of them, perhaps 35 million. Outside Europe another 50-100 million likely died. It is impossible to know with any certainty or accuracy, but the sources agree that the death toll was dramatic, swift, and catastrophic. Initially, the rapidity of its spread and devastation caused consternation and horror. Germs and bacteria were unknown as were the rodent and flea vector. Contagion was poorly understood. Still, epidemic diseases were known to spread by some poorly understood mechanism, so doctors and family members neglected the sick out of fear. Some fled cities to the countryside.

History of surgery and surgical training

In the medieval period, the technology of surgery improved significantly as surgeons learned more anatomy, developed new procedures, and became more confident in their abilities. This process continued into and through the Early Modern Period as guilds and governments insisted on more and better training for surgeons, reflecting the growing importance of surgery. Learned physicians had university degrees, but surgeons had usually trained through the apprentice system and were regulated by guilds rather than by learned faculties. A young boy would be apprenticed for 3 years to learn the rudiments of bloodletting, bandaging, aligning fractures, lancing boils, and seeing more complicated problems. To complete this training, he would become a journeyman who traveled and worked with different master surgeons, learning more complex procedures absorbing as much surgical know-how (or tacit knowledge) as possible, along with some theory when possible. Returning to his home town where he had apprenticed, he would undergo a rigorous examination in both the practical application of his surgical skills and his theoretical knowledge of anatomy, wound healing, materia medica, and other areas of surgical knowledge. Lacking Latin, barber-surgeons were usually examined in their local vernacular language.

Smallpox pandemic

It traveled with Europeans to the New World (in the Columbian Exchange). It caused virgin soil epidemics; it killed millions of immunologically naive natives and prepared the way for the European conquest in what historian Alfred Crosby famously termed ecological imperialism. It killed millions in Mexico and Peru leading to the Spanish conquest of the Aztec and Incan Empires. In North America, it devastated Native Americans and cleared the land for English colonists (Pilgrims and Puritans) in the Massachusetts Colony. Smallpox is caused by the Variola virus, but there are three forms of the virus: V. major, V. minor, and V. vaccinae. The first is the most virulent; the second is much less severe; and the third is also known as cowpox that produces only mild disease in humans. Epidemic smallpox was common in Europe and was endemic during the 15th or 16th c. It was primarily a "relatively innocuous" disease of children until the late 1600s when it became "the most lethal illness of the young." It periodically broke out into devastating epidemics that continued into the 18th century and essentially replaced the plague as the Europeans' most feared epidemic disease. It was virulent, blinding, disfiguring, and killing millions. It did not respect social rank or affluence. However, a person who has had smallpox is immune for life.

The history of syphilis illustrates interesting aspects of medical knowledge and medical technology.

It was clearly related to sexual intercourse. It was immediately understood as contagious and clearly seemed to be an external disease that entered the body. An early treatment technology, gum guaiac, was brought back from the New World. Its preparation was difficult, but it was so highly thought of that it was called 'Holy Wood.' Another treatment technology involved sweating patients by raising their temperatures in heated rooms. However, mercury soon became the treatment of choice, leading to the sardonic witticism, "spend a night with Venus and then a lifetime with Mercury." Paracelsus was an early advocate of mercury to treat syphilis and leprosy. Eventually, the microscope revealed the pathogen, Treponema pallidum, in 1905. The Wassermann Test was developed in 1906 for definitive diagnosis. The disease went by numerous different names in Europe following its 'appearance' in the late 15th century: the French Disease, the Italian Disease, the Spanish Disease, or 'the Great Pox.' Fracastoro called it 'syphilis,' and this name persisted over time.

Thomas Sydenham and Johne Locke

Just as Hippocrates' thought was shaped by pre-Socratic Greek philosophy, Sydenham was influenced by the empirical philosophy of his friend and fellow physician, John Locke. Locke believed that our best source of knowledge about the natural world was the evidence of the five senses, the evidence with which the brain is able to comprehend the natural world. Sydenham, like Hippocrates, held firmly to the understanding of observation, experience, and knowledge. Sydenham was even referred to as "the English Hippocrates." Learned medicine had obviously traveled a long way from the bedside observations and the experience of Hippocrates if learned physicians could diagnose and treat through the mail. Sydenham and others believed it had traveled a long way in the wrong direction with too much theory, scholastic reasoning and contempt for empirics and hard-earned experience. Sydenham rejected scholastic debates and the theories they produced. Instead, he wanted to restore the importance of bedside medicine and its appreciation for the facts obtained from clinical experience and observation of patients and illnesses.

Tagliacozzi

Tagliacozzi used a 'pedicle flap' from the patient's forearm that was sewn to the bridge of the nose. To allow blood vessels to grow from the face into the flap, the forearm was secured to the head for two weeks before the flap was severed from the arm and secured to the face. Tagliacozzi's technique was superior to earlier techniques and was in use until the early 20th century. So, recognizable advances in surgical training, licensing, and techniques that began during the medieval era continued into the Early Modern Era. Even barber-surgeons created new knowledge, developed new technologies, got good results, and elevated the status of the surgeon with respect to that of the learned physician.

Paracelsus' idea of chemical causation

Lois Magner sees Paracelsus' idea of chemical causation as a precursor to modern concepts of "metabolic diseases, dietary disorders, and certain occupational diseases." He joined older, alchemical notions with newer chemical ideas in order to explain and treat diseases. He rejected most herbals, but he used opium (laudanum), derived from the poppy. In place of herbals, he advocated for the use of minerals or metals - mercury, arsenic, lead, iron, copper, sulfur, and antimony, several of which are poisonous. He thought the addition of specific chemicals to the body to correct a deficiency was better than removing humors through bleeding, purging, or sweating to rectify a humoral imbalance. This idea just missed being a significant advance in medical knowledge because of his emphasis on "occult energies" and "the influence of the celestial bodies" on human health and disease. Knowing that many of these chemicals were poisonous, he claimed that, 'the poison is in the dose,' meaning very small amounts would not poison and could be therapeutic. However, he continued to embrace astrological influences when most other scholars were leaving these outdated notions behind. Nevertheless, his efforts to invoke chemical causes for diseases such as gout led him to suggest that the body was unable to excrete certain chemicals that coalesced into gouty nodules in joints, gallstones, or kidney stones, "one of the earliest attempts to advance a chemical aetiology for a malady." His introduction of chemical remedies was a substantial contribution. Later taken up by his followers, "these medicines soon found their way into standard medical armamentaria." His few followers became known as iatrochemists, and Iatrochemistry dealt with the chemical treatment of diseases.

Notes on syphillis "today"

Magner notes that the variable course of syphilis, with only about 30% going on to tertiary syphilis, would have convinced physicians that mercury treatments were 70% effective. Says she, perhaps "the long history of the medical use of mercury proves nothing but the strong bond between therapeutic delusions and the almost irresistible compulsion to do something ... [furthermore] the widespread belief that mercury cured syphilis ... [made it] almost impossible to conduct clinical trials in which patients were deprived of this remedy." In 1905, syphilis was found to be caused by a bacterium known as Treponema pallidum, and in 1906, the Wassermann Test was developed to more accurately diagnose the disease and distinguish it from other diseases. The test also made it possible to better elucidate the various stages of the disease.

Paul-Louis Simond

Many historians believe the second pandemic finally abated after the Great Plague of Marseilles in 1720. Following this well-recognized narrative, the third plague pandemic began with the Plague of Hong Kong in 1894, where Alexandre Yersin isolated and identified the bacterium, Yersinia pestis as the causative pathogen. Four years later, Paul-Louis Simond described the role of the flea, Xenopsylla cheopis in the transmission of the disease from infected rats to humans.

How did they treat syphillis?

Mercury was sometimes used as an ointment that was rubbed on the skin, or it was given as calomel. Mercury is toxic, especially with prolonged use. Given orally as calomel, it erodes gums and loosens teeth, in addition to its other, systemic effects. Nevertheless, calomel was a popular medicine and physicians did not want to give it up. General William Hammond, the Surgeon General of the Union Army during the Civil War, thought calomel was both useless and toxic, so he removed it from the army's formulary. He was correct, of course, about its toxicity. Nevertheless, physicians in the army medical corps vehemently disagreed. They were so completely convinced of Calomel's efficacy and safety that they had him removed from office. This was a good example of how doctors can be absolutely confident and certain, even when their 'knowledge' is completely wrong. Magner also notes that Arthur Conan Doyle's recommendation of nitroglycerine based on a single case, illustrated "the way the medical literature became a repository of anecdotal material published as medical research." A few early publications about treatments for Covid-19 also illustrated this same issue of anecdotal material masquerading as accepted knowledge.

Mercury

Mercury, for example, became a mainstay in the treatment of syphilis, leading to the sardonic adage, 'spend a night with Venus and then a lifetime with mercury.' Mercury fit into the humoral theory because it is a sialagogue; that is, it promotes salivation and was one way of correcting a humoral imbalance. One aspect of mercury poisoning is loosening and loss of teeth, and it is likely that chronic mercury poisoning might have caused George Washington to lose his teeth.

Miasma theory and the plague

Miasma (foul-smelling air) would carry the disease, inflicting it on those it contacted. Foul air was appreciable to any nose, and the smell of the air in most medieval towns was truly vile. Moreover, the miasmatic theory of transmission was not opposed to person-to-person transmission, because infected humans, too, could give off miasmatic vapors when they exhaled foul-smelling breath, transmitting the infection to others nearby. Plague was a disease involving all the inhabitants of a city and had to be addressed by civic officials entrusted with the care of the city, becoming a problem of 'public health.' Because miasma was thought to result from rotting organic matter, civic officials could justify certain aspects of a novel idea: 'public health policy.'

Did the first plague influence society so much?

Mordechai and Eisenberg maintain that the so-called devastation in the wake of the plague was much less significant. They believe the Plague of Justinian was not severe enough to cause these historical changes.

Jan Baptiste van Helmont

The Dutch iatrochemist, Jan Baptiste van Helmont (1580-1644 CE), like Paracelsus, held to the notion of disease specificity and the belief that certain diseases should be treated with specific chemicals, but he was less abrasive and thus had more influence on his fellow physicians. Van Helmont Believed that diseases were discreet entities. Like Paracelsus, he rejected the Galenic notions of humoral imbalance. He also rejected the Galenic concept of plethora and the efficacy of bloodletting, actually proposing a clinical trial of several hundred patients divided into treatment groups with and without bloodletting to determine which group would do better. Van Helmont, however, was far ahead of his time. 200 years later that study of bloodletting was carried out in Paris, and, using numerical data, it supported his disdain for bloodletting.

Humoralism is challenged

Moreover, humoralism, itself, was beginning to be challenged by a new, important conception of diseases as distinct and specific entities, contrary to the humoral view of disease as diffuse humoral imbalances. For example, there was something very specific about the bubonic plague that continued to revisit European citiesand which ravaged London with a vengeance in 1665. It seemed to have an existence of its own that could be identified as it approached a city. It made its arrival and sickened a percentage of the population, causing similar symptoms in different patients. Finally it departed and traveled elsewhere. The same could also be said of many other diseases, which seemed to be marked by certain signs and symptoms that were specific for that particular disease. Buboes (plague), pustular eruptions (smallpox), a hot, red, swollen big toe (gout), or genital chancre sores (syphilis) all seemed to be specific diseases. Additionally, cinchona bark (or, Jesuits' bark), discovered in Peru during the 7th c., was a remedy for intermittent fevers (malaria), and only for intermittent fevers. It was not useful in treating other types of fevers. Even so, the authority of humoralism and Galen was waning, and the authority of Hippocrates and his English disciple, Sydenham, was waxing.

Morgagni and natural history of disease

Morgagni correlated the natural history of a disease, as outlined in the case summary of the disease, with the manifestations of the disease in different organs, a crucial step in understanding how diseases cause clinical signs and symptoms. He could show that a bloody cough, hemoptysis, was related to disease in the lung; hematuria indicated disease of the kidneys, ureters, or bladder; jaundice was the result of liver disease, and a stroke on the right side of the brain produced weakness on the left side of the body. Morgagni pointed to the 'seat' of the disease; he localized the disease to specific organs.

More on Morgagni

Morgagni was the antecedent of the modern pathologist. He dissected hundreds of cadavers in an effort todetermine how diseases affected the body's organs. He also examined the clinical, case histories of the individuals he dissected in order to correlate the clinical findings with his anatomical, autopsy findings. In 1761, at age 80 and after fifty years of work, he published his findings from 700 autopsies in On the Sites and Causes of Disease (De Sedibus et Causis Morborum— or De Sedibus). One could easily argue that it marked the true beginning of scientific medicine. Soon translated into vernacular languages, De Sedibus was a voluminous, expensive opus. Morgagni also correlated what the physician wrote about the disease in the living patient with what he (Morgagni) found at autopsy. Ultimately, morbid anatomy (anatomical pathology) would lead to major advances in medical knowledge. But, his work was all 'after the fact,' creating new knowledge but too late to help the patient involved. The actual prevention of disease would have seemed a long way off to Morgagni.

Sydenham classifies disease

Most importantly, Sydenham began to classify diseases into different external entities based on their own, specific characteristics, and this constituted the beginning of a modern ontological understanding of diseases as having some reality external to the individual. Disease was not just the loss internal harmony by the disruption of humoral balance. Rather it existed outside the body, had specific characteristics, and could spread from place to place. Sydenham's attempt to create a nosology based on the symptoms of specific diseases presaged more sophisticated 18th and 19th c. nosologies. His early attempts at forming a nosology of diseases involved such obvious distinctions as acute diseases (smallpox, plague, etc.) versus chronic diseases (arthritis, gout, etc.). Sydenham focused on the symptoms that made up a disease, but he maintained a special interest in infectious, epidemic diseases, especially plague, which ripped through London in 1665. He tried to group acute diseases based on the collection of symptoms with which they presented and the seasons when they occurred. For chronic diseases, such as gout, the symptom complex might have been correlated with causes such as excessive wine or rich food. Because the bacterial revolution and germ theory were still 200 years in the future, he (along with most others) attributed many diseases to environmental conditions. Ancient diseases were classified a capite ad calcem — from head to foot — it was a rudimentary classification, but it was a classification nonetheless. Sydenham's nosology was more modern, but it was only one of several to be developed over time, and there was no one, single point in time when medicine became 'modern.'

Lady Mary Wortley Montagu

One victim was Lady Mary Wortley Montagu whose great beauty was sadly marred by it; her husband was the British consul in Constantinople. In 1717, she observed Turkish women inoculating or 'engrafting' children with smallpox matter. This was also called variolation (or, inoculation). A small amount of dried pus of a pustule from a patient with a 'mild' case was introduced into a patient by a scratch or by drawing a suture (coated with pus from a pustule) through the skin. This caused a minor case of smallpox (fever, rash, and malaise), but it also conferred lasting immunity to the disease. She was not the first to document it, a description of inoculation had been presented to the Royal Society (RS) a few years earlier in 1714 but nothing came of it - it was not adopted. Before returning to England, Lady Mary had her son inoculated in Turkey with the help of an English surgeon stationed there. Her daughter was later inoculated in England by the same surgeon, but there was significant opposition from the medical community. Lady Mary, who was close to the Princess of Wales, persuaded the Prince and Princess to variolate their children (after first testing it on condemned prisoners). Adoption by the Royals quickly overcame the resistance of any physicians who had initially objected to it. The procedure soon spread throughout Europe. Nevertheless, the risks (death or full-blown disease sparking an epidemic) remained, and the stage was set for a better, safer procedure.

The two previous strands of thought about epidemic diseases

The first was that they were contagious (from contagio) and could be contracted from contact with the sick. The other was that it was something diffuse in foul-smelling air, and this something might be concentrated in the exhaled breath of the sick, allowing them to spread it to others. Some scholars argue that a variable emphasis on these two beliefs characterized ancient, medieval, and early modern thought about epidemics. Often both strands were implicated with different authors stressing one more than the other. The two strands of thought, however, were not necessarily contradictory or mutually exclusive. Some authors might say, for example, that the cause was a miasma, but that a sick individual concentrated the evil odors in his lungs and exhaled them as a miasmatic breath, sickening others. Only late in the 19th century would this uncertainty be settled and the germ theory articulated, but noticeable theorizing (or speculation) was made in the Early Modern Period.

Pare and new surgical techniques

Paré reintroduced the ligature, probably invented by Herophilus and Erasistratus. Celsus wrote about it ~50 CE, and Galen used it, as did Albucasis ~1000 CE and Henri de Mondeville ~1300. The ligature was not a new idea, but Paré seems to have relied on it more than others during amputations, allowing him to limit the use of the red-hot iron to cauterize bleeding arteries. Paré and others learned from battle trauma and made important new innovations that could then be used to treat civilian trauma. As though these battlefield innovations were not enough for Paré, he revived the technique of podalic version to facilitate difficult deliveries in childbirth. It had been used in antiquity, especially by Soranus, to promote a breech delivery when the fetus remained lying in transversely in the uterus. Though not much use on the battlefield, it demonstrates his supple versatility and ingenuity. By the 17th century, surgeons were achieving more promising results in the treatment of trauma, and their new methods could be transferred to the civilian sector. English surgeon, Joseph Binns, left records of 402 cases of trauma from battles, occupational injuries, riding falls, and brawls. His results were good: 337 (84%) were cured or improved with his treatments, while 53 (13%) died; about 3% survived their injuries but did not improve.

Paracelsus

Philippus Aureolus Theophrastus Bombastus von Hohenheim, known to history as Paracelsus (1493-1541 CE) - the name he preferred - was an alchemist, an astrologer, a physician and an original thinker. His reputation has suffered from his emphasis on occult events, astrology, and alchemical ideas and by the fact that he was a difficult man to like, constantly getting into nasty disputes and legal squabbles. Nevertheless, he remains an important figure in the history of Early Modern medical knowledge. His career and thought remind us of how many scholars and physicians in the past relied on things we do not consider 'rational' today.

Black Death bacterium and development of human plague

Probably the worst pandemic in human history was the Black Death in the mid-14th century. The disease was bubonic plague caused by a bacterium named Yersinia pestis. The bacterium lives in the intestinal tract of fleas. The fleas live on rodents (black rats, prairie dogs). The rats may live in cities, in close proximity to humans. If (or when) the rodent population is overwhelmed by infestation with fleas and infection by the bacterium, the fleas desert their dying rodent hosts and transfer to humans and may cause bubonic plague.

Fracastoro and syphillis

Recall that Girolamo Fracastoro elaborated on the ideas of Varro and Galen concerning the 'seeds of disease' and introduced the concept of fomites that could transport a contagion from one person to another. He also coined the name 'syphilis' for a disease that seemed to appear in Europe abruptly at the end of the 15th century. It was contagious, common, and frightening. Because syphilis seemingly appeared de novo in the very last years of the 15th century, many believed it was brought back from the New World by Columbus' sailors. See what you think based on the YouTube video that is assigned this week. Prof Lois Magner discusses four theories for its origin: Medieval astrologers thought it was caused by a dreadful alignment of certain planets. Another possibility is that syphilis was already present in Europe but was confused with leprosy and unrecognized. Yet another theory is that it developed out of the African disease, yaws, during the Age of Exploration. Historically the most prominent theory is that it was a New World disease contracted by the sailors on Columbus' first voyage and brought back to Europe as part of the Columbian Exchange. Its clinical presentation, that is, its signs and symptoms, vary and may mimic many other diseases. Because of this highly variable presentation, it has often been called the 'great pretender,' the 'great mimic,' and/or the 'great imitator.'

History of magnifying glasses and microscopes and Robert Hooke

Simple magnifying lenses were developed in the 13th c. and were soon used to better visualize small creatures, initially as simple, single-lens microscopes. Sometime after 1600, two lenses were put in line to form the first compound microscope, probably in Holland. The initial impact of the compound microscope, however, was not nearly as dramatic or pivotal. It was not as immediately useful as the telescope in the production of new knowledge. In fact, it was three decades before images were made revealing very small structures and 65 years before Robert Hooke (1635-1703 CE) published his important text, Micrographia, with its remarkable images of various small objects, including fleas, lice, and a slice of cork. Hooke's image of a slice of cork is famous. Its honeycomb appearance reminded him of the small, simple spaces, or cells, in which monks lived in Monasteries, and he called them 'cells.' Ironically, while the term, 'cell,' would assume great importance in living tissue, Hooke had not seen living cells. Nevertheless, the term he coined has taken on hugely important meaning.

Galen's influence remains

Still, bloodletting remained the most common procedure for surgeons, partly because patients requested it. 'Plethora' (the dangerous build-up of blood) was still believed to be the underlying cause of many ills: fever, headache, malaise, and apoplexy. Everyone, it seems, still agreed with Galen. Galen's influence remained daunting and was difficult (if not impossible) to overcome. While many surgeons were probably content just with better results in old procedures, a few created entirely new procedures to expand the technology of surgery to previously untreatable problems. Nasal reconstructions to repair a partially amputated nose (usually from a duel) had been done for decades before Gaspare Tagliacozzi (1545-1599) perfected it in the 16th century.

Sydenham and Herman Boerhaave

Sydenham's influence spread to Europe, where HermanBoerhaave (1668-1738 CE), in Leiden, was also a confirmed empiricist with little use for speculative theories. He believed Galen's theories were based on inadequate empirical knowledge. Instead, Boerhaave saw the body as a system of vessels or pipes conveying fluids. It was a mechanical model that could be understood without reference to ancient texts or theories. One needed only empirical evidence gained from experimentation and observation to understand health and disease. Boerhaave believed the patient and the disease were the best instructor, he established "a hospital especially for teaching purposes," anticipating the "hospital medicine" of the 19th c., and drawing many medical students to Leiden for exposure to hospital patients. The 19th c. is often called the 'scientific century' - it was when medicine became scientific.

The Early Modern Period and especially the 18th century saw the development of numerous new theories

The Early Modern Period and especially the 18th century saw the development of numerous new theories that tried to correct weaknesses in Galenic theory or even refute it outright. In the first part of chapter 10 (pages 245 to 262), Porter meticulously details numerous physicians and their work, both on the Continent and in the British Isles. However, much of this is beyond the scope of a semester-long survey of 5,000 years of medical history. Therefore, read through these pages quickly and note two things. First, "biomedical findings did not often deliver clinical success," meaning that these theories did not translate into successful treatments. Second, although there were many attempts to advance a new theory to replace Galenism, none of them was truly successful. In fact, the various attempts were more like branches off a tree trunk that led to dead ends. The 18th c. saw growing dissatisfaction with Galenism, but the lack of any agreed upon alternative theory or treatment left physicians with no alternative to traditional treatments, especially when dealing with patients who wanted and expected the usual treatments. So, at the end of the Early Modern Era, Galen's theories and influence were weakening, and physicians were actively searching for a replacement theory on which to base their understanding of disease and on which to base rational treatments. Lecture 18, will take us to 19th-c. scientific medicine, but the 18th-c. still has a few surprises.

Early Modern Peiod of European history and the printing press

The Early Modern Period of European history and medical history is often defined as the three-hundred-year period from 1500 to 1800. Our historical and present-day calendrical divisions are human contrived and subject to debate. The onset and the end of the period are often defined by the European discovery of the Americas in 1492 and the French Revolution in 1789 (and/or industrialization about c. 1800). However, two important events of the middle of the 15th c. contributed so much, that it is difficult to exclude them: the printing press and the fall of Constantinople in 1453. Gutenberg's development of moveable type for his printing press (c. 1440) and the rapid European spread of the printing press began a new era in scholarship. By 1500, there were ~1,000 printing presses in western Europe, and by 1550, large cities had hundreds of them.

Others thought diseases were spread by bad air:

The Hippocratic author of Airs, Waters, Places ascribed epidemic disease to the air that a population breathed. In Roman medical thought, Vitruvius (75-15 BCE) argued that swamps were unhealthy because they emitted bad air (or, miasma) which caused disease. Varro (116-27 BCE), was more explicit, blaming swamp diseases on "tiny creatures, invisible to the eye, floating in the air, entering the human body through mouth and nose, and causing sickness."

Reaction to the second plague relating to faith

The best medical advice of the time was practical: 'flee fast; flee far; and flee for a long time.' That is, 'get away from the city, the disease, the sick, the dying; get away fast and stay away.' Parents deserted sick children, spouse deserted spouse, and children left parents to die alone and untended. Some, believing they were doomed, became unrestrained and licentious. The Church, the clergy, and the physicians had nothing useful to offer, and the reputation of all of them suffered. Many believed that the cause of such a calamity could only be God's anger and desire to punish humans for their sins. Numerous observers implicated either avaricious clergy, a malicious Jewish conspiracy, or the lascivious and lustful ways of upper class women as the final provocation for God's anger. The Paris Medical Faculty, however, determined that the "distant and first cause of this pestilence was and is the configuration of the heavens ... causing a deadly corruption of the air around us." It seemed clear that the disease was spreading by some mechanism, and foul, polluted air (or miasma) was a popular explanation.

Significance of the microscope

The compound microscope became a major technology in biology and medicine. Its usefulness prompted more improvements in the preparation of tissues, especially staining techniques to reveal different cells, different aspects of cellular structure, and different bacteria. It is difficult to overestimate the importance of the new technology of microscopy. With the problems solved, Brown identified the nucleus and Schwann developed the cell theory. Forty years later, Robert Koch would begin identifying disease-causing bacteria with his microscope. The microscope provided empirical access to what had been purely theoretical. There had been analogous reasoning from mites and 'seeds of disease,' to invisible organisms that cause disease, but there had been no real evidence, until the advent of microscopy. What was previously invisible was made visually accessible. The microscope revealed entirely new empirical evidence that would be used to support new theories of disease causation. By 1888, Ernst Abbé, in Germany, had produced a compound microscope that could magnify to the theoretical limits of the wavelength of light. Each new observation provided evidence for new hypotheses about disease causation, beginning the process of challenging older hypotheses and theories. Kircher had examined a patient's blood and believed he saw microscopic organisms, and, while most historians think he probably did not, Van Leeuwenhoek certainly did see them. The microscope made the theory of animate, microscopic organisms real and no longer speculative, even though it took time to work this empirical evidence into Germ Theory. In the mid-19th c. microscopy "led to many sightings of bacteria and other microorganisms, and speculations about their relations to humans beings and human diseases." Finally, the so-called animalcules could actually be seen and empirically verified. Thus a theory that incorporated invisible organisms could be justified on empirical, not just rational, grounds. People had begun to question the validity of miasma theory and the humoral paradigm in the Early Modern Period, there had been no other theory with which to replace them. With the empirical evidence revealed by microscopy, however, a new theory could begin taking shape in the mid-19th c. Even so, before a new paradigm could be adopted, it would first have to be created, and that would not begin to happen until the mid to late 19th century.

First plague pandemic

The first plague pandemic began with the Plague of Justinian (541 to 549 CE), which was basically the first wave of a long recurring pandemic that lasted about two centuries from 540 CE until about 750 CE. The Plague of Justinian was bubonic plague, which still has a mortality rate of 15% even in the age of antibiotics. Before the mid-20th century, the mortality rate varied between 40-90% depending on various circumstances, and it has devastated past populations and societies. It is likely that 20-25% of the inhabitants of Constantinople died in the Plague of Justinian; it devastated surrounding towns and farmlands, severely depleting Justinian's tax revenues and frustrating his goal of reuniting the two halves of the old Roman Empire. Unable to reestablish the authority, wealth, and military power of the old Roman Empire, he could not decisively conquer his Persian enemies.

History of plague

The history of plague is an academic course of its own, with new sub-disciplines (paleobiology, paleopathology, and paleogenetics) and with scientists' new-found ability to identify disease pathogens in the dental pulp of individuals who died thousands of years ago. We are very fortunate here at USC to have a world authority on plague. Prof Sharon DeWitte teaches an anthropology course about past plagues. In this lecture, we will look briefly at three major pandemicsof plague that have occurred since the mid 6th century CE. This field of pandemic history is exciting and burgeoning with new evidence, new historical interpretations, fascinating new controversies, and new-found relevance with Covid-19.

Syphillis allows for development of antimicrobial drugs.

The history of syphilis is important for another reason: the development of one of the first antimicrobial drugs to combat an ongoing infectious disease in the body. Because so many treatments seemed to harm patients as much as they helped, German physician/research scientist, Paul Ehrlich, began searching, in 1900, for the elusive holy grail of medical therapy: a treatment that cures a disease without injuring the patient. Chemicals were known that destroyed T. pallidum, but Ehrlich needed one that was harmless to patients. The German chemical industry produced huge amounts of synthetic dyes in 1900.

The idea of an educated surgeon

The more exalted 'master surgeon' (perhaps with some learned medicine), was often examined in Latin, indicating his higher status. Over time, master surgeons became more common. Surgeons who were 'educated' became more common in the 16th and 17th c., and the number of barber surgeons dwindled. Each generation, wanting more for its offspring, sent them to cathedral schools to become literate, numerate, and Latinate before being apprenticed. The sons of barber surgeons had a much better chance of becoming 'educated surgeons' than had their fathers. Both the educational and training process improved as did the finished product: well-trained and well-educated surgeons. In the 16th c., governments began to examine and license them. One of the best schools for surgeons was the battlefield and there was no shortage of battlefields in Early Modern Europe (more 170 wars w/ >5.5m killed betw. 1500 and 1800).

Natural history of a disease

The natural history of a disease is really just the understanding of how a disease develops over time and the likelihood it will permanently harm or kill a patient. The natural history of a disease process is an essential concept and harks back to the Hippocratic emphasis on prognosis. The natural history of some diseases, such as the common cold, is relatively benign. Many diseases have a benign, self-limited course, and just cause temporary discomfort. The natural history of other diseases, such as bacterial meningitis or bubonic plague, may be fast, fulminant, and fatal. The natural history of Covid-19 is extremely variable, as we all know. The natural history of bubonic plague is different for its different forms: bubonic, pneumonic, and septicemic. It kills many of the people it infects, but not all, unless it is septicemic, which is almost always overwhelming, and rapidly fatal. Recall, for example, that Guy de Chauliac documented the first two forms of bubonic plague in Avignon. In doing so, he was describing the natural history of two forms of the disease. It is crucial to know the natural history of a disease in order to properly evaluate possible treatments. For instance, no one would treat the common cold, or even influenza (which is occasionally fatal) with dangerous, untried drugs, because the risks of the drug might be greater than the risks of the disease. Likewise, as we shall see in a later lecture, understanding the natural course of an untreated disease is necessary to evaluate a treatment: does treatment improve the outcome compared to the natural history of the untreated disease? This was a problem with syphilis.

Second plague pandemic

The second plague pandemic began with the infamous Black Death that arrived in Europe in 1347 and lasted until 1353 CE. It was the first wave of a recurring pandemic, lasting until the mid-1700s. These were sensible precautions, but none of them was sufficient to completely protect a city. Eventually, the first epidemic (The Black Death) subsided and people thought they were safe, but, as with the Justinianic plague, it returned in waves every 10-20 years for centuries. Many historians believe the second pandemic finally abated after the Great Plague of Marseilles in 1720.

Third plague pandemic

The third plague pandemic is arguably still going on and is traditionally dated to its arrival in Hong Kong in 1894. This is being revised as historians realize that it was certainly present in China before 1894, and some may ultimately suggest there was no significant break between the second and third epidemics. The third plague pandemic began with the Plague of Hong Kong in 1894, where Alexandre Yersin isolated and identified the bacterium, Yersinia pestis as the causative pathogen. Steamships spread the Hong Kong epidemic around the world (save only Antarctica), causing the San Francisco Plague of 1900-1904 (~100 deaths). It spread out of San Francisco to rodents and became enzootic among prairie dogs in the American Southwest, where it still lingers. Plague is prevalent in parts of Africa, the Republic of the Congo and Madagascar where it still lingers in endemic (and occasionally epidemic) form since its spread to Africa after 1894. Additionally, the 1994 plague in India constituted a contained outbreak of the disease that caused widespread panic but only a few dozen deaths. The WHO argues that the 3rd pandemic ended in the 20th c. Others contend that it persists to the present day because of these residual pockets of disease among rodents and humans.

Giovanni Cosimo Bonomo

The work of Giovanni Cosimo Bonomo (1663 CE - 1696 CE) in the late 17th century was also important to the developing theory that external agents caused diseases in humans. He recognized that human scabies was caused by mites. The scabies mite is not truly microscopic, and others had remarked on it for centuries, but Bonomo documented his very complete microscopic findings in a letter of 1687 and in an English synopsis published in 1702. Bonomo found the causative agent in "a very small white Globule, scarcely discernible," and examining it with a microscope "found it to be a very minute Living Creature, in shape resembling a tortoise." He described how the mites moved from one host to infect another through skin contact; how they laid eggs; and how they caused the symptoms of scabies by "biting and eating, one single one happening sometimes to make several Pustules, of which I have often found two or three together."

Overlap of Late Antiquity and Early Medeival Era

There is overlap at the end of Late Antiquity and the Early Medieval Era. There is overlap at the end of the Medieval Period and the beginning of the Early Modern Period of European and medical history. Moreover, it is customary to talk about the 'long 19th century' (1789-1914). So, although these dates (1500-1800) are not completely arbitrary, they are certainly subject to debate and are best seen as approximations, rather than precise limits.

Galileo and the telescope

This same innovative development also created the first telescope, and Galileo quickly built his own. Within a decade, he had visualized the moons of Jupiter and imperfections of our moon. In 1610 he recorded these previously unknown findings in The Starry Messenger, immediately generating unexpected, new knowledge along with considerable controversy.

More on the concept of "seeds of disease" and fomites

Though not exactly opposed to miasma theory, the concept of 'seeds of disease' added a more tangible element than simply foul odors in the bad air. Offering an alternative to a purely vaporous miasma, the metaphorical concept of 'seeds of disease' encouraged debate and dialogue. Ultimately, it directed medical thinking toward a tiny, even invisible, pathogenic organism external to the patient that could cause disease. Similarly, the concept of fomites advanced the understanding of contagion by offering a more tangible means of disease transmission than just odor and a way to break the transmission. Fomites such as clothing, woolens, bed linens, spoons, or other objects could be disinfected, or burned if necessary. Likewise, fumigation might successfully cleanse a room, a house, or a city of fomites that transmitted diseases. Finally, while a quarantine of individuals and their goods would not prevent the miasmatic spread of a disease, it would be useful in preventing the spread of fomites and any seeds of disease they carried. While Fracastoro should not be credited with developing an early version of germ theory, he did begin a process: development of a new intellectual atmosphere that would be receptive to further elaboration and developments, ultimately leading to germ theory centuries later. Conspicuously missing in the 16th century was any empirical evidence of these 'seeds of disease.' Critics could, and did, simply point out the complete lack of evidence of their existence in order to reject Fracastoro's theory. Evidence was crucial, and it would not become apparent until the invention of a new technology, microscopy. And, although the first versions of the compound microscope appeared in ~1620, it was not truly useful until the 19th c.

Galen and William Harvey

To get from the Galenic physiology of the Early Modern Period to our present understanding of the circulation of the blood, we must follow the work of William Harvey(1578-1657 CE). However, we must first acknowledge that no matter how essential the work of Harvey, he did not work in a vacuum. While it is true that no one was trying to refute Galen's physiology or to find 'the circulation,' preceding scholars had begun to question Galen's infallibility. Ibn al-Nafis (13th c.) discussed the pulmonary transit, but his work was unknown in Europe.

Characteristics of syphillis

Today, we know that syphilis has three stages. The first is marked by the characteristic chancre sore on the genitalia several weeks after infection. The second stage usually involves a diffuse rash and may include some non-specific malaise and discomfort. An intermediate period is usually a long latency period that may last several years. The tertiary stage only occurs in about a third of untreated cases, but it causes cardiac and neurological problems often leading to dementia and/or death if untreated. Unfortunately, syphilis can also be transmitted to a fetus during pregnancy and delivery causing congenital syphilis. Luckily, most congenital cases today can be cured with antibiotics. The social ramifications of syphilis were profound: it was considered a disease of moral failure. Countries named it after their enemies. The stigmata of syphilis marked out those of ill-repute. It endangered innocent sexual partners and unborn children. Ultimately, it inspired the notion that civilization predisposes mankind to diseases: "Civilization is syphilization," and it led to blood testing for marriage licenses. It prompted several clinical studies of the disease that were so egregiously unethical that they are used today as models of warped medical research; something about the disease and its reputation almost seemed to tempt researchers to run amok.

Morgagni and Jenner

Two individuals really characterize the changes in medicine over the course of the 18th c. Giovanni Batista Morgagni (1682-1771 CE) graduated from medical school and began his career in the opening year of the new century, 1701. Edward Jenner (1749-1823 CE) was born in mid century and lived into the 19th century, but he, too, epitomized the spirit of the 18th-c., which has been called "the adolescence of modern scientific medicine." It was also the period of European intellectual development known as the Enlightenment. The Enlightenment writes Magner, "inspired the search for rational systems of medicine, practical means of preventing disease, improving the human condition, and disseminating new ideas." Still, as already noted, there was no one point in time when medicine suddenly became 'modern.' The development of modern medicine was a slow, evolutionary process and is likely still a 'work in progress.' There is no reason to think medicine has fully matured. It is almost certain that dramatic, even revolutionary, changes and advances will continue to occur.

Dissolution of Roman Empire after Justinian I

Ultimately, the two empires fought to a draw, succeeding only in exhausting themselves. Both were weakened and no match for the military force of the new Islamic Empirerising in the mid-7th century, after the death of the Prophet Mohammed in 632 CE. The Sassanian Empire fell to Muslim armies in 651 CE. The Byzantine Empire survived another 8 centuries until the Fall of Constantinople, which fell to the Ottoman Turks in 1453 CE.

More on Early Modern Europe

Universities produced more educated men, and more women became literate. Scholars' new knowledge produced a flood of new books, while students and graduates clamored for them. The popularity of vernacular languages sped the dissemination of presses in each country in order to produce editions of popular texts in each local vernacular. Constantinople and the Byzantine Empire fell to the Ottoman Turks in 1453, and many Greek scholars fled the new Islamic regime in Constantinople. They traveled to Christian Europe carrying books and manuscripts with them, especially ancient works in the original Greek. These ancient Greek writings fanned the ardor of European humanism. Reacting against medieval scholasticism, humanists wanted to study classical authors in the original Greek. After fleeing Constantinople, Greek scholars often found employment teaching Greek or translating the Greek texts directly into Latin. Medical humanists also searched for original Greek editions in order to form their own ideas about what Galen had written, instead of relying on Islamic versions translated from Arabic. The fall of Constantinople led to a windfall of previously unavailable Greek editions, and the technology of the printing press multiplied it many times over. There were numerous Greek scholars in the Renaissance, especially in Venice, ready to teach, translate, or interpret.

Public health policies during second plague

Various Italian city-states instituted early 'public health policies:' In Venice, sick travelers were refused admission, burial practices were specified, and surgeons were permitted to take on physicians' duties. In Florence, officials rid the city of animal carcasses, animal dung, and rotting vegetation. In Pistoia, newcomers, crowds of people, and the importation of woolen goods were prohibited. In Ragusa officials developed the novel idea of sequestering ships, sailors, and travelers from suspect areas for 40 days, or quarantena in Italian, adding the term of quarantine to the language and the concept of quarantine to subsequent notions of public health regulation.

War and surgery

War was omnipresent and new gunpowder firearms were more destructive than arrows, and swords. Tissues were crushed and torn; bones shattered with muscle and skin ripped apart. A dagger or sword might carry bacteria deep into wounds, but the crushed and necrotic tissue of GSWs was a better breeding ground for infections and almost inevitably led to gangrene. Better procedures for cleaning wounds and for better control of bleeding to salvage limbs were needed, but better techniques of amputation were also needed. Unfortunately our old bugbear, (misleading) theory, got in the way: GSWs were believed to be poisoned by the gunpowder. Boiling oil was poured into the wound to sterilize it - probably useless, but excruciatingly painful.

PLague tractates

We saw earlier that medieval surgeons began creating new surgical knowledge. The medieval plague inspired physicians to create a new genre of medical writing called plague tractates. These scholarly treatises written by physicians from the mid-14th c. to the 17th c. informed other physicians and patients how best to avoid or treat the plague. These subjects had not really been addressed in any systematic way by ancient authors, and these plague tracts reflected the creation of new medical knowledge by medieval physicians. They began to disassociate medicine from astrology. They informed physicians and patients of new medical knowledge. They addressed public health issues, such as disinfecting the air and the environment. They began the process of giving more serious consideration to the meaning of contagion. They furthered the development of "medical scholarship ... as a sophisticated enterprise, fully responsive to contemporary interests, methodology, and controversies in natural philosophy." The plague gradually led some scholars to question how a plague pandemic could be reconciled with the humoral theory: how could "vast numbers of people [experience] the same humoral imbalance at almost precisely the same time?" This did not fatally undermine Galenism or humoralism, but it did begin a long gradual process of questioning, ultimately leading to the works of Girolamo Fracastoroand Athanasius Kircher. 200 years later, these two men would posit the transmission of infected particles called fomites (Fracastoro) and the possibility of tiny living animalcules that caused disease.

Challenging Galen in the time of Harvey

While he was challenging Galen's notion of physiology, Harvey remained a Humoralist and a Galenist at heart. He did not renounce humoralism or the need for bloodletting. Just as the work of Vesalius did not immediately overturn Galen's authority, neither did that of Harvey. Their efforts simply "opened a few cracks in the Galenic system ... [but] the number of challenges to Galenism multiplied and, by the eighteenth [???] century, it had lost its hold as the basis of learned medicine." The actual change from premodern thinking to modern thinking was not sudden or abrupt. Even if the conceptual change itself was great and revolutionary, the process of this change was slow and evolutionary. Still, some began to realize that Galen's idea of plethora was being challenged by Harvey's circulating blood, which did not accumulate in one area or overload the entire body. Thus, the Galenic rationale for bloodletting was becoming tenuous. Furthermore, if Galen had been wrong about the liver constantly making blood, then what else might he have gotten wrong? Over the next century, the premodern ideas and theories of Hippocrates, Aristotle, and Galen began to give way to new, more modern and more 'scientific' ideas and theories.

Scientific Revolution

With the Scientific Revolution of the 16th and 17th c., 'facts' became increasingly important while theories, hypotheses, and scholastic disputes lost some of their luster.