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ALEXANDRIAN MEDICINE

Aristotle’s royal pupil, Alexander, routed all his rivals, lamented there were no more worlds to conquer, and expired in 323 BC, supposedly exclaiming, ‘I die by the help of too many physicians.’ His destruction of the Persian Emperor Darius III had brought Egypt within the hellenistic sphere of influence, and after Alexander’s death science gained a prominent place at the court of King Ptolemy, who ruled from 323 to 282 BC and established his capital at Alexandria, at the mouth of the Nile.

King Ptolemy’s main cultural creations, the Alexandrian Library and the Museum (sanctuary of the Muses) installed Greek learning in a new Egyptian environment: Archimedes, Euclid and the astronomer Ptolemy were later to teach there. The library became a wonder of the scholarly world, eventually containing, it was said, 700,000 manuscripts, and its facilities included an observatory, zoological gardens, lecture halls and rooms for research.^*

Thanks to Alexander’s conquests, the hellenistic world stretched from the Persian Gulf to Sicily, with Greek becoming the lingua franca of the elite. One consequence was a remarkable increase of new information on animals, plants, minerals and drugs. Alexandria also attracted medical talent, notably Herophilus of Chalcedon (c. 330–260 BC and his contemporary, Erasistratus of Ceos (c. 330–255 BC). Their writings having been lost, we know about them only through later physicians. Cornelius Celsus (fl). AD 60 reported that they dissected, or at least experimented upon, living humans, which is not inconceivable, for Greeks may have used their privileged status in Alexandria to experiment on their inferiors, especially condemned criminals.

Herophilus was apparently a student of Praxagoras of Cos (fl. 340 BC), who had improved Aristotelian anatomy by distinguishing arteries from veins. Praxagoras saw the arteries as air tubes, similar to the trachea and bronchi, conducting the breath of life (pneuma) from the lungs to the left side of the heart and thence through the aorta and other arteries to the whole body. The arteries stemmed from the heart; the veins, by contrast, Praxagoras believed, arose from the liver, their function being to carry the blood, created from digested food, to the rest of the body. The combining of blood and pneuma generated innate heat.

Herophilus practised medicine in Alexandria under the first two Ptolemies, apparently dissecting human cadavers in public. He wrote at least eleven treatises. Three were on anatomy: it was he who discovered and named the prostate and the duodenum (from the Greek for twelve fingers, the length of gut he found). He also wrote on the pulse as a diagnostic guide, on therapeutics, ophthalmology, dietetics and midwifery, and a polemic ‘Against Common Notions’.

Continuing Praxagoras’ differentiation between veins and arteries, Herophilus pointed out that the coats of the arteries were much thicker than those of the veins. Unlike Praxagoras, however, he held that the arteries were filled not with air but with blood. His most striking dissection feat was the delineation of the nerves. Demonstrating their source in the brain enabled him to conclude that they played the part preceding thinkers had ascribed to the arteries: transmitting motor impulses from the soul (intelligence centre) to the extremities. Rebutting Aristotle, he thus established the importance of the brain, distinguishing the cerebrum from the cerebellum and displaying the nerve paths from the brain and spinal cord. His description of the rete mirabile, the network of arteries at the base of the brain, shows he dissected animals as well as human corpses, since it does not exist in humans.

Herophilus also devoted attention to the liver and to ‘veins’ ending in glandular bodies which, he believed, nourished the intestines but did not pass to the liver. These ‘veins’ must have been the lacteals or chyle-vessels, whose function was explained by Aselli some two thousand years later. Praxagoras’ interest in the pulse was taken up by Herophilus. Identifying pulsation as derived from the heart, he developed a speculative classification of different classes of pulse, on the basis of magnitude, strength, rate and rhythm, and is reputed to have tried to calculate pulse by means of a portable water clock.

Erasistratus is far more nebulous and controversial. He supposedly studied medicine in Athens before settling in Alexandria, where he experimented on living animals and perhaps humans. His main discoveries concerned the brain which, like Herophilus but unlike Aristotle, he regarded as the seat of intelligence. He too distinguished the cerebrum from the cerebellum, described the cerebral ventricles within the brain, and distinguished between motor and sensory nerves. Nerves were hollow tubes containing pneuma (‘spirit’ or air), which transmitted sensation, enabling muscles to produce motion.

In a tradition going back to Alcmaeon, he also believed that pneuma alone – not blood – was contained in the arteries: it was taken in through the lungs, piped to the heart (which he compared to a blacksmith’s bellows) and then pumped out to fill the arteries. Blood by contrast was formed in the liver and carried by the veins. Why then was it blood that spurted from a cut artery? It was drawn in, Erasistratus reasoned, because nature abhorred a vacuum.

Erasistratus has been portrayed as an early mechanist, because of his model of bodily processes: digestion for instance involved the stomach grinding food. Yet this may be a caricature created by Galen for polemical purposes. Even Galen applauded his remarkable investigations of brain anatomy, while being scathing about his other views, particularly the idea that the arteries contained air alone. Erasistratus was clearly a radical; for want of evidence, he is also a riddle.

In the following centuries medicine, like philosophy, split into sects: Hippocratics, Herophileans and Erasistrateans were later challenged by the Pneumatists, who regarded pneuma as a fifth element which flowed through the arteries, sustaining vitality. All such sects were later given the label of ‘rationalist’, to signal their antagonism to the Empirics, a band of physicians led by Heraclides of Tarentum (fl. 80 BC), who spurned medicine based on speculation about hidden disease causes in favour of one grounded on experience. What mattered, Empirics claimed, was not cause but cure, and so they collected case histories and remedies. Knowledge, they held, could be better gained at the bedside than by dissection; what counted was which drugs worked. Hence theory must bow to experience – a claim later opponents, principally Galen, rejected as shallow.

MEDICINE IN THE ROMAN ERA

Greek medicine spread throughout the Mediterranean, not least to Italy, where the southern cities shared Greek culture – doctors at Elea, Tarentum and Metapontum were like their colleagues in Athens or Alexandria. Rome was different. No-nonsense Roman tradition held that one was better off without doctors. Romans had no need of professional physicians, insisted authors like Cato (234–149 BC), for they were hale and hearty, unlike the effete Greeks. ‘Beware of doctors’, he cried; they would bring death by medicine. ‘It is our duty, my young friends’, reflected Cicero (106–43 BC), ‘to resist old age; to compensate for its defects by a watchful care; to fight against it as we would fight against disease; to adopt a regimen of health; to practise moderate exercise; and to take just enough food and drink to restore our strength and not to overburden it.’

Romans enjoyed bad-mouthing Greek physicians: according to Pliny (AD C. 23–79), who deplored the recent influx of ‘luxury’ and worthless Greek physicians, an inscription, echoing Alexander, was now sprouting up on monuments in Rome: ‘It was the crowd of physicians that killed me.’^*

Romans liked to think healing should take place in the family, under the care of the paterfamilias, who would dispense herbs and charms. Cato, who dosed his family on cabbage soup, derided Greek physicians as the antithesis of Roman virtue: they were frauds who cheated patients and ‘have sworn to kill all barbarians with their drugs’. Prejudices such as these may explain the tardy emergence of native Italian physicians.

The contrast drawn by Cato and Pliny between homespun healing and hellenistic speculation was xenophobic prejudice. The real difference was not between Greece and Rome, but between rustic medicine and that of the big city. Greek medicine arrived with city life as Rome was hellenized. For long professional doctors (medici) in Italy were immigrants; the first noted Roman practitioner, Asclepiades (c. 120–30 BC), was a native of Bithynia in Asia Minor. Modified by his pupil, Themison of Tralles (fl. 70 BC), his doctrines gave rise to the Methodist sect. Its physiology was based not upon the Hippocratic four humours but upon corpuscular theory. In the body the proper arrangement of atoms and their intermediate pores produced health; any obstruction or undue looseness led to disease, so health was the balance between tension and relaxation. This atomist physiology enabled the doctor to reduce diagnosis to the ‘common conditions’ – the constricted, the lax and the mixed – deducible from visible symptoms. Hence the Asclepiadean or Methodist doctor did not need intimate familiarity with the life history of his patients: plain symptoms were sufficient. Cure was by opposites, enlarging narrow pores and reducing large ones, for which Asclepiades promoted massage, exercise and cold-water bathing. His slogan cito, tute et jucunde – swiftly, safely, sweetly – is reflected in his rejection of heroic bleeding, his preference for gentle medicines, his prescription of wine and his stress on convalescence. Self-styled Asclepiadeans nourished for three centuries, though their rejection of philosophical reasoning riled Galen, who sneered at their pre-packed therapies.

More light on the infiltration of Greek medicine into Rome is offered by the physician Scribonius Largus (c. AD 1–50). Born in Sicily, he probably learned his craft from hellenistic practitioners on the island, and in AD 43 he accompanied the Emperor Claudius on his campaign to subdue Britain. His sole surviving medical text is a Latin handbook of drug recipes, the Compositiones. It contains 271 recipes for conditions from headache to gout, all claimed of proven value. In his preface, Scribonius set out his views on medical ethics, becoming our earliest witness to the use of the Hippocratic oath. How widespread was his endorsement of a professional ethic is unclear, for no other ancient writer made such an open commitment.

The early empire brought the first surviving survey of medicine in Latin. An encyclopaedic compilation, Celsus’ Artes [The Sciences] originally contained at least twenty-one books, of which only the eight devoted to medicine survive in full. No professional physician but a wealthy estate owner who presumably treated his family and friends, Celsus (fl. AD c. 30) was acquainted with both theory and treatments, writing in an elegant Latin which won him the title of the Cicero of the physicians.

The eight books are introduced by a long preface tracing the story of medicine from the time of the Trojan war, and lamenting the rise of clashing sects: Dogmatists, who stressed the need to seek out unseen causes; Empirics, whose emphasis was on experience; and Methodists, wedded to ‘common conditions’. Medicine, in Celsus’ view, required not just experience but reason.

Celsus’ first book is on the preservation of health and on diet; Book 2 deals with signs the doctor should watch for, and remedies; Book 3 concerns diseases of the whole body – fevers, jaundice and so on; Book 4 lists the diseases of individual body parts in the top-to-toe order which was to become customary; and the lengthy Book 5 falls into two parts, a description of various drugs, and treatments for bites and ulcers. Book 6 handles treatments of diseases of the parts of the body, again from top to bottom. Subsequent books deal with surgery, opening with a brief history of the art, and moving on to a list of surgical conditions occurring anywhere in the body, before examining surgical techniques for individual parts, again from head to heel. The final book deals with fractures, ruptures and luxations, including such ambitious operations as removal of bone splinters from the skull. After surgery the physician must be alert to the four cardinal signs of inflammation – calor, rubor, dolor and tumor (heat, redness, pain and swelling). As the first major medical author writing in Latin and offering a summary of the whole of medicine in a single work, Celsus exercised a powerful influence.

The medical colossus of the Roman era is Galen (AD 129-c. 216), but he had significant contemporaries who stand in his shadow, in part because he belittled them, in part because their works, unlike his, survive only in fragments. One was Aretaeus of Cappadocia (fl. AD 140) who proclaimed his loyalties by writing in Greek and frequently alluding to Hippocrates. His work, known in Latin as De causis et signis acutorum et diuturnorum morborum [Acute and Chronic Diseases] provides the best disease descriptions of any surviving ancient author. A ‘rationalist’, he inclined to the pneumatic school, believing that in the universe and in man alike, pneuma (spirit) bound everything together, and any change in it led to illness.

Aretaeus made disease the hub of his inquiries, recording nothing about his patients – or himself for that matter. He gave fine descriptions, among other things, of dropsy and diabetes, mental disorders and epilepsy. Diabetes represented ‘a liquefaction of the flesh and bones into urine’, so much so that ‘the kidneys and bladder do not cease emitting urine’. His description of tetanus gives evidence of his clinical experience:

Tetanus consists of extremely painful spasms, which are a peril to life and very difficult to relieve. The attack begins in the jaw muscles and tendons, but spreads to the whole body, because all bodily parts suffer in sympathy with the one first affected.

There are three types of spasms. Either the body is stretched, or it is bent either backward or forward. With stretching the disease is called tetanus: the subject is so rigid that he cannot tarn or bend. The spasms are named according to the tension and the position of the forward and backward arching. When the posterior nerves are affected and the patient arches backward, we call the condition opisthotonus; when the anterior nerves are affected and the arching is forward, the condition is called emprosthotonus.

Another doctor then active was Soranus, practising in Ephesus AD C. IOO. His Gynaecology, the largest early treatment of that subject, should be understood in the context of traditional Hippocratic thinking on the diseases of women, which presumably reflected prevailing male prejudices. Children born at seven months were said, implausibly, to have a greater chance of surviving than those born at eight; the ‘wandering womb’ was blamed for hysteria-like illnesses; and the female constitution was an imperfect version of the male. Soranus, however, was sceptical of many of these traditions, and dismissive of the ‘wandering womb’. His Gynaecology, which enjoyed wide circulation, is divided into four sections. The first, dealing with conception and pregnancy, also discusses virginity and the right age for intercourse (not before menarche, at about fourteen). Advice was given on contraception, though Soranus disapproved of abortion by mechanical means. The next section treats labour, recommending the sitting position and the Roman birthing-chair. In case of difficult labour, he taught ‘podalic version’ – easing a hand into the uterus and pulling down one of the baby’s legs, so that it would be born feet-first. The third part examines women’s maladies, including uterine fluxes and womb-caused diseases, and the final section is concerned with problems in the birth itself: how to remove the placenta after birth and tie the umbilical cord.

Another physician associated with Ephesus was Rufus (AD 70–120), who learnt anatomy in Alexandria and spent some time in Rome. He wrote commentaries on several Hippocratic writings, accepting the doctrine of the four humours and of cure by opposites. His writings were praised by Galen. Galen’s sun, however, outshone his ideas, as it did everyone else’s.

GALEN

Galen’s dominion over medicine for more than a millennium was partly the consequence of his prolific pen. More of his opus survives than of any other ancient writer: some 350 authentic titles ranging from the soul to bloodletting polemics – about as much as all other Greek medical writings together. He had vast erudition and a matching ego.

Born in AD 129 in Pergamon (now Bergama, Turkey), one of the fairest cities in the Greek-speaking empire, Galen was the son of a wealthy architect, Nicon, and a shrewish woman (‘My mother … used to bite her serving maids, and was perpetually shouting at my father’). He enjoyed a long, lavish, liberal education; when he was sixteen, his father was visited in a dream by Asclepius, after which the son was piously steered towards medicine. He studied with Alexandrian teachers and travelled in Egypt, learning about drugs from India and Africa. Returning home in 157, he was appointed physician to the gladiators, a job which enlarged his anatomical and surgical expertise, since wounds afforded windows onto the body. But Pergamon was provincial, and in 162 he left for Rome, where public debates against Methodists and high-profile public anatomical displays spread his fame. One of his party tricks, revealing his genius for self-advertisement as well as experiment, was to sever the nerves in the neck of a pig. As these were severed, one by one, the pig continued to squeal; but when Galen cut one of the laryngeal nerves the squealing stopped, impressing the crowd. Leading senators and dignitaries began to employ him, and from AD 169 Galen was in imperial service, first with the emperor’s son, Commodus, and later a succession of emperors. He liked reminding readers that his patients were of the highest rank. ‘Something really amazing happened when the emperor [Marcus Aurelius] himself was my patient’, he wrote:

Just when the lamps were lit, a messenger came and brought me to the Emperor as he had bidden. Three doctors had watched over him since dawn, and two of them felt his pulse, and all three thought that a fever attack was coming. I stood alongside, but said nothing. The Emperor looked first at me and asked why I did not feel his pulse as the other two had. I answered: ‘These two colleagues of mine have already done so and, as they have followed you on the journey, they presumably know what your normal pulse is, so they can judge its present state better.’

When I said this, he bade me, too, to feel his pulse. My impression was that – considering his age and body constitution – the pulse was far from indicating a fever attack, but that his stomach was stuffed with the food he had eaten, and that the food had become a slimy excrement. The Emperor praised my diagnosis and said, three times in a row: ‘That is it. It is just as you say. I have eaten too much cold food.’

He then asked what measures should be taken. I replied what I knew of a similar case, saying: ‘If you were any plain citizen of this country, I would as usual prescribe wine with a little pepper. But to a royal patient as in this case, doctors usually recommend milder treatment. It is enough for a woollen cover to be put on your stomach, impregnated with warm spiced salve.’

Expert in one-upmanship, Galen couched an inflated sense of his importance in terms of the dignity of medicine, scolding colleagues as dimwits. He was invariably right; there is no denying that he was an erudite man and an accomplished philosopher, particularly in constructing an image of the organism as a teleological unity open to reasoning. For him, anatomy proved the truth of Plato’s tripartite soul, with its seats in the brain, heart and liver; and Aristotelian physics with its elements and qualities explained the body system.

Philosophy should promote medicine, Galen taught, though the physician must master philosophy – logic (the discipline of thinking), physics (the science of nature), and ethics (the science of action). Philosophy and medicine were thus counterparts: the best doctor was also a philosopher, while the unphilosophical healer (the Empiric) was like an architect without a plan. A good physician would practise for the love of mankind, while accepting his due rewards in fame and fortune.

The patient’s trust was essential in the healing process. It could be won by a punctilious bedside manner, by meticulous explanation, and by mastery of prognosis, an art demanding experience, observation and logic. Galen brought psychosomatic conditions to light, including uneasiness amongst defendants in court cases or those whose pulses raced through guilty passions.

Galen prided himself on being more than a fine clinician; he was a medical scientist. He performed dissections, mainly of apes, sheep, pigs and goats and even of an elephant’s heart, but not of humans. He knew much skeletal anatomy, but, dissection being out of the question, little internal human anatomy. Two mistakes were particularly critical for the future. Dissections of calves revealed a network of nerves and vessels, the rete mirabile at the base of the brain, earlier found by Herophilus, which he assumed also existed in humans. This, he said, was the site where the vital spirits in the arteries turned into animal spirits. He also misleadingly described the liver (which he believed to be the source of the veins) as grasping the stomach with its lobes as if by fingers, an image derived from dissection of pigs or apes. Forced to apply animal findings to humans, his human womb also had cotyledons like a dog’s. Such mistakes aside, his explanations of anatomical phenomena in terms of the teleology of a divinely ordered universe were internally coherent and provided a rational basis for further investigation.

Gross anatomy and experiments offered paths to understanding, but Galen did not restrict himself to sensory perceptions. By combining his observations with Platonic speculations about the macrocosm at large, he formulated models of concealed bodily structures. Each part functioned only when its basic elements were properly adapted, and any change would result in functional failure or disease. The unknown was thereby explained in terms of a structural/functional physiology. His systematizing zeal was both a boon and a bane.

Galen presented his work as ‘perfecting’ Hippocrates’ legacy, and this gives his oeuvre a remarkable unity, fusing the clinical and the theoretical. Take his writings on fever: fever might result from either an excess of yellow bile, black bile or phlegm (a condition he called cacochymia), or from an excess of blood (plethora). Surplus humours might accumulate in some bodily part where they would cause putrefaction and excessive heat or fever. To remove such superfluities and restore humoral balance, he advocated energetic blood-letting. The physician should let blood from a patient not only when he was ill but prophylactically, whenever a fever was on the cards. Indications were given of when and how much blood to draw, depending on the patient’s age and constitution, the season of the year, the weather and the place. Instead of the earlier Hippocratic treatment of fevers by starvation, Galen urged venesection (letting blood from the veins) to cool the body.

He justified blood-letting in terms of his elaborate pulse lore. Written in the early 170s, his sixteen books on the pulse were divided into four treatises, each four books long. The first, On the Differences between Pulses, displayed his learning, logic and linguistic skills. In the next four books On the Diagnosis of Pulses, he explained how to take the pulse and interpret it, raising key questions. How was it possible to tell whether a pulse was ‘full’, ‘rapid’ or ‘rhythmical’? Such questions he resolved partly from experience and partly by reference to earlier authorities.

On the Causes of Pulsation addressed anatomy. Although Galen was convinced, pace Erasistratus, that arteries contained blood from the heart, his idea of pulsation was quite different from ours. The heart and the artery contracted simultaneously and arterial expansion and contraction were separate, active movements. In contraction, superfluities were expelled; in expansion, atmospheric air was taken in to cool things down and, by mixing with blood in the heart, to generate vital spirits (pneuma). It was this vital spirit which was mainly responsible for creating the pulsative power within the coats of the artery.

Blood, Galen taught, was made in the liver, incorporating ingested foods in the form of chyle; it then moved to the extremities carrying natural spirits which supported the vegetative functions of growth and nutrition. This dark venous blood, passing from the liver to the right ventricle of the heart, divided into two streams. One passed to the lungs via the pulmonary artery; the other crossed the heart through ‘interseptal pores’ into the left ventricle, where it mixed with pneuma (air), became heated, moved thence from the left ventricle to the aorta, and finally to the periphery. His belief that the veins originated in the blood-making liver, carrying nutrition to the parts whenever needed, while the arteries originated in the heart, was one of the errors in his model of the circulatory system which, after dominating medicine for well over a millennium, was challenged by Renaissance anatomy.

From a clinical standpoint, Galen was principally concerned to teach the doctor to read the various pulse phenomena. This he provided in the final part, On Prognosis from the Pulse, where he adopted a double strategy. The first two books described the complaints a specific pulse type might betray: for example, the ‘double-hammer pulse’ was a frequent sign of heart weakness. The last books detailed the sort of pulse found in specific disorders: for example, in hectic fevers the pulse increased in frequency and rapidity.

Whatever the disorder – even blood loss – Galen judged bleeding proper. All depended on knowing where and when to do it, and how much blood to take. For severe conditions he recommended phlebotomy twice a day; the first should be stopped before the patient fainted, but the second time the physician could bleed as far as unconsciousness. Convinced that nature prevented disease by discharging excess blood, he pointed out that menstruation spared women many diseases – gout, epilepsy, apoplexy – to which males were prone. The quantities of blood he removed were large, and would often, to our thinking, have been harmful. His teachings on plethora and venesection remained influential until the nineteenth century.

Galen took clinical Hippocratic medicine and set it within a wider anatomo-physiological framework. In broad terms this built on the Platonic doctrine of a threefold division of the soul, which distinguished vital functions into processes governed by vegetative, animal, and rational ‘souls’ or ‘spirits’. Animal life was possible only because of the existence of pneuma. Within the human body, pneuma (air), the life breath of the cosmos, was modified by the three principal organs, the liver, heart and brain, and distributed by three types of vessels: veins, arteries and nerves. Pneuma, modified by the liver, became the nutritive soul or natural spirits which supported the vegetative functions of growth and nutrition; this nutritive soul was distributed by the veins. The heart and arteries were responsible for the maintenance and distribution of innate heat and pneuma or vital spirits to vivify the parts of the body. The third alteration, occurring in the brain, ennobled vital spirits into animal spirits, distributed through the nerves (which Galen thought of as empty ducts) to sustain sensation and movement.

For Galen, anatomy, logic and experience fitted together. Not least because he had an explanation for everything, Galenic medicine proved monumental, as he intended it should:

I have done as much for medicine as Trajan did for the Roman Empire when he built bridges and roads through Italy. It is I, and I alone, who have revealed the true path of medicine. It must be admitted that Hippocrates already staked out this path … he prepared the way, but I have made it passable.