Pathfinders

by Jim Al-Khalili

  We begin, as we must when digging into the origins of medicine, with ancient Egypt. Despite all the wonders and achievements of the Egyptians, their civilization differed from those of Greece and Babylon in the complete absence of any theoretical or metaphysical concepts associated with its science. For the Egyptians, science was merely a practical tool, and even medicine fell into this category. This is why Plato writes in his Republic of the Greeks’ love of learning and the Egyptians’ love of riches. The Egyptians possessed exceptional embalming skills, but had surprisingly little knowledge of human anatomy. Like other ancient civilizations in India and China with medical traditions stretching back to prehistory, much of Egyptian medicine seems crude and silly to us today. For instance, their remedy for migraine was to rub the side of the patient’s head with a poultice made from the skull of a catfish so that the pain could pass through to the animal. But I cannot stress often enough that we should not be too harsh in our judgement of such quaint notions. For they are no sillier than many popular therapies still practised around the world today, including in the so-called ‘enlightened’ West.

  In any case, the ancient Egyptians did develop many sensible procedures, such as the use of lint, the suturing of wounds, supporting fractures with wooden splints, and the heating of a lancet to cut out tumours. Much of Egyptian medicine was later to pass to the Greeks, who would turn it into a proper scientific discipline, culminating in the great works of Galen.

  Further east, the Vedic tradition in India has a long history going back to origins in magic, religion and mythology and is still practised in some parts of the world today as a form of complementary medicine. It holds that each of the five elementary substances that make up the universe – earth, water, fire, wind and space – corresponds to a constituent in the human body: tissue, humour, bile, breath and cavities. As with all ancient medicine, and indeed most ancient science, this is mainly a mixture of superstition interwoven with science, but there is always much of practical use and importance.2

  The Greeks of course excelled in the field of medicine – like almost everything else – and boast the two greatest physicians of antiquity: Hippocrates (fl. 420s BCE) and Galen (c. 130–216 CE), two men separated by a remarkable half a millennium. I say ‘remarkable’ here only because, while we often mention these two men in the same breath when talking about Greek medicine, this is somewhat equivalent in timescale to saying that the two giants of modern European cosmology are Copernicus and Stephen Hawking. Hippocrates’ legacy to medicine can be compared with that of Pythagoras to mathematics. Like the earlier mathematician, his life and achievements are somewhat shrouded in mystery. Both founded schools of thought that were to become more important than their founders. And like the Pythagorean mathematicians, Hippocratic physicians made an astonishing and lasting contribution to the field of medicine. They understood that the human organism is a complex whole and that true wisdom came from understanding, aiding and stimulating its natural activities. They were the first not to separate body and soul, but to consider man as an integral part of his physical and sociological environment.

  Galen is an even more important figure in the history of medicine – many might argue the most important in history. His work and ideas influenced all medical knowledge in the world for more than a thousand years. He was born in Pergamum in c. 130 CE, a city famous at the time for its many physicians. After studying in Alexandria he returned to Pergamum to become physician to the College of Gladiators (clearly bringing him much work in surgery and dietetics). In his early thirties he went to Rome, where he gained fame for his public lectures. Following further travel in the Middle East he returned to become personal physician to the emperor. He was a prolific publisher of books on all aspects of medicine.

  Medical knowledge in medieval times built extensively on the foundations laid by the ancient Greeks. The most highly prized, and among the first to be translated into Arabic, were several of Galen’s medical books. Galen believed that the human body’s health depended on a balance between different types of fluids called humours, which circulated through the body, each of which if out of balance would cause illness and a change of temperament. They were (and here I am simplifying the description): yellow bile, which in excess would make the patient bilious or bad-tempered and nauseous; blood, too much of which would make the patient sanguine and flushed; black bile, which in excess would make the patient lethargic and melancholic; and phlegm, which could make the patient ‘phlegmatic’ or apathetic and emotionally detached. Galen argued that illnesses occur when there is an excess of one of the humours and the cure lies in somehow draining some of it from the body. To do this he recommended techniques like cutting to induce bleeding or the use of emetics to induce vomiting.

  Not all of Galen’s ideas were so absurd, however. His account of medical anatomy was based on what he learnt from the dissection of monkeys, as human dissection was not permitted, but his work remained unsurpassed in its detail until Andreas Vesalius published his famous illustrated book on human anatomy De humani corporis fabrica in 1543. Galen’s account of the activities of the heart, arteries and veins endured for more than a thousand years, until Ibn al-Nafīs described the process of pulmonary transit in the thirteenth century and, much later, William Harvey established in the seventeenth century that the blood circulates with the heart acting as a pump. Galen also developed many nerve-ligation experiments that supported Plato’s idea that the brain is the command centre of the body controlling all the muscles (rather than the heart, as had been thought by Aristotle). Even as late as the nineteenth century, medical students would still refer to some of Galen’s ideas; such was his enduring influence on medicine.

  But the physicians of the Islamic Empire were acutely aware that Greek medicine was only one source of medical knowledge. For a start, Islam places a premium on cleanliness and personal hygiene, and it is a requirement of every Muslim to carry out the wudhū’ (the ritual washing of hands, feet and face before prayer). At a time when the Christian West was obsessed with magic, viewing illness either as divine punishment for sins or, worse, as possession by evil spirits, medics in the Muslim world were following the Greek tradition of trying to understand disease and illness scientifically and finding ways to treat them rationally. What is more, maintaining a healthy body and caring for the sick was now seen as a religious duty. Of course, one has to be careful not to make too strong a contrast between thinking in the East and West, for notions involving magic and demons also existed in the Islamic world.

  Into this world came al-Rāzi. We encountered him earlier as a chemist, the man who would take the classification of chemicals further than anyone before him had done, thereby improving on the Greek theory of the four elements by classifying substances according to their chemical properties deduced from laboratory-based experimentation. Like al-Kindi a generation earlier, al-Rāzi was a polymath who also excelled as a philosopher and a musician. But his achievements in a wide range of disciplines pale into insignificance when held up alongside his work in medicine. Here, his fame and impact are as great as those of Galen, and his accomplishments even greater than those of the most famous scholar of Islam, Ibn Sīna, a century later.

  Al-Rāzi was born in Rayy in c. 854. Today very little remains of this ancient city and the modern Rayy is no more than a densely populated suburb of the vast metropolis of modern Tehran. In his youth, al-Rāzi studied all the subjects one might expect a bright young man to be grounded in at that time, including literature, philosophy, mathematics, astronomy and music. He wrote on a wide range of these subjects, but most of these writings have unfortunately been lost. Luckily, however, many of his most important medical texts have survived, in both Arabic and Latin, and were used extensively alongside those of Galen across Europe in the Middle Ages.

  He was an obsessive scholar who devoured all the books he could lay his hands on. Tragically, he slowly went blind later in life, due, according to some accounts, to cataracts; others claim that it was fr
om the long-term damage caused by fumes from the toxic chemicals he worked with early in life as a chemist. However, a quite different reason for his blindness reaches us from the account that appears in Ibn al-Nadīm’s Fihrist. It is from an unnamed source, who describes his regular visits to al-Rāzi in Rayy: ‘I never went in to him without finding him reading or transcribing, whether to make a rough draft or a revised text. He had wet eyes because of all the beans he would always eat, and he became blind due to this at the end of his life.’3

  It is said that al-Rāzi took up the study of medicine after his first visit to Baghdad, when he was around 30 years old. While there, he studied under the well-known physician Ali ibn Sahl (a Jewish convert to Islam, whose father produced the first Arabic translation of the Almagest). Al-Rāzi soon surpassed all his teachers and his reputation grew as the most respected medic in the world. He would combine his vast knowledge of Galenic texts, Hippocratic wisdom and ethical values with an empathic and compassionate nature as a skilled clinician and teacher.

  In the Islamic world, al-Rāzi’s name will always be associated with some of the earliest hospitals. In Abbāsid times, these were not known by their current Arabic name of mustashfa, but rather by the Persian word bīmāristān (from Pahlavi vīmār or vemār, meaning ‘sick’ and -stan, the suffix for ‘place’). These institutions were initially modelled on Nestorian Christian establishments, particularly when it came to their administration and reliance on charitable funding. Indeed, one finds that most physicians of ninth- and tenth-century Baghdad were Christian or Jewish.

  Charitable endowments within Islamic law, called waqf, began to be set up around this time and some of the funds from these trusts went into building hospitals.4 These multiplied throughout the empire with large cities such as Cairo and Córdoba also boasting dozens of hospitals.

  Soon after the turn of the tenth century, al-Rāzi was called upon by the Caliph al-Muktafi to help in selecting the site of a new hospital. He had pieces of fresh meat hung up in various districts of Baghdad. A few days later, he checked the pieces, and he selected the area where the least rotten one was found, stating that the ‘air’ was cleaner and healthier there. Following the death of the caliph in 907, al-Rāzi returned to his home town of Rayy and took charge of the hospital there.

  Later, under the Caliph al-Muqtadir (r. 908–32) several more new hospitals were built in Baghdad.5 The largest of these, al-Bīmāristān al-Muqtadirī, was built by the vizier Ali ibn Īsa in a part of Baghdad known as Sūq Yehya on the east bank of the Tigris. Al-Rāzi, still head of the hospital in Rayy at this time, was recruited again to take over as director of this new establishment.

  The renowned Arab traveller Ibn Jubayr describes visiting Baghdad and the then two-hundred-year-old al-Muqtadirī hospital:

  This great establishment is a beautiful structure stretching along the banks of the Tigris. Its physicians make their rounds every Monday and Thursday to examine patients and prescribe for their needs. At the physicians’ disposal are attendants who fill drug prescriptions and prepare food. The hospital is split up into various wards, each containing a number of rooms, giving the impression that the place is as a royal palace in which every convenience is provided.6

  Among the features in medieval Muslim hospitals that distinguished them from their contemporaries elsewhere were their higher standards of medical ethics. Physicians there treated patients of all religions or ethnicities. They were expected to have obligations towards their patients, regardless of their wealth or background. These ethical standards were first laid down in the ninth century by Ishāq bin Ali al-Rahawi, who wrote The Conduct of a Physician (Adab al-Tabīb), the earliest known Arabic treatise dedicated to medical ethics.

  Much of the medical work in Baghdad during the time of al-Rāzi was overseen by Sinān ibn Thābit, the son of the great mathematician and translator Thābit ibn Qurra. Sinan was the equivalent of chief physician and was famously ordered by the Caliph al-Muqtadir to ensure that all physicians sat an examination in order to qualify to practise. They even adopted and adapted to Islamic thought the famous Hippocratic oath.

  Al-Rāzi introduced many practical and progressive medical and psychological ideas. He ran the psychiatric ward in the Baghdad hospital at a time when, in the Christian world, the mentally ill were regarded as being possessed by the devil. In fact, he is acknowledged as the father of the fields of psychology and psychotherapy. He also attacked those without medical training who roamed the cities and countryside selling their nostrums and ‘cures’, and criticized them in his book Why People Prefer Quacks and Charlatans to Skilled Physicians, showing his frustration with the way they achieved the fame and fortune that was often denied those with proper medical training. And he wrote of the pity he felt towards those good physicians whose patients would not follow their advice on diet or treatment but then blamed them when they did not recover.

  He also made a distinction between curable and incurable diseases, and commented that in the case of advanced cases of cancer and leprosy the physician should not be blamed when he could not cure them. He warned that even highly skilled physicians did not have all the answers, and wrote the aptly titled monograph Even the Most Skilful Physicians Cannot Heal All Diseases.

  To maximize their chances of successful diagnosis, he advised all medical practitioners to keep up to date with the latest knowledge by constantly studying medical texts and exposing themselves to new information. On medical ethics and medical training, he borrowed much from the writing of both Hippocrates and Galen, which influenced greatly the medical training manuals he wrote.

  As Galen had done before him, and as Ibn Sīna would do a century later, al-Rāzi synthesized all known medicine by sorting and categorizing it into different areas, from eye diseases to gastro-intestinal complaints, from dietary advice to case studies. So comprehensive were his working files that they were assembled posthumously into one of the greatest medical texts ever written, al-Kitab al-Hāwi. It is still the largest Arabic medical textbook, filling twenty-three volumes in a modern printing. It now survives only in Latin, as Liber continens, but it became one of the most highly respected and frequently used medical textbooks in Europe for several centuries. In fact, it was one of just nine texts that composed the entire library of the medical faculty of the University of Paris in 1395. It is to this book that the origins of disciplines like gynaecology, obstetrics and ophthalmic surgery can be traced. His magnum opus, the Great Medical Compendium (Kitab al-Jāmi’ al-Kabīr), is often confused with the posthumously published corpus of his notes. What is probably his best-known text, a monograph on smallpox and measles called Kitab al-Judari wal-Hasba, which also survives in Latin, is the oldest reliable account of these two illnesses. It is widely regarded as the ultimate masterpiece of Muslim medicine.

  It is immediately obvious from reading the Liber continens that this is much more than a medical textbook. Scattered throughout is evidence that al-Rāzi was a practising clinician with many personal experiences and case notes. Often, these notes were meant to be studied alongside the Greek treatises on those subjects. For instance, Hippocrates had written in his Epidemics on tuberculosis (‘pthisis’ or ‘consumption’) as a widespread and almost always fatal disease involving a fever and the coughing up of blood. Al-Rāzi supplements Hippocrates’ notes with a case study on the possible dangers of trying to suppress the coughing with medicine:

  A consumptive [i.e. suffering from tuberculosis] elder came to us. He had been repeatedly coughing up much blood over a long period of time. Then it became much more distressing for him, so he took hazelnut and water, which stopped the cough. He felt relief each time he took this, and [apparently] recovered completely. Then he died … Consequently, one should avoid remedies that suppress expectoration, except in cases where the matter flows down from the head.7

  One of the most fascinating insights into al-Rāzi’s work as a practising clinician was recounted to me by a friend of mine, Peter Pormann, a leading expert on the history
of medicine. He tells of al-Rāzi carrying out the earliest known example of a clinical trial employing a control group.8 Al-Rāzi begins by selecting two sets of patients, all of whom are showing early symptoms of meningitis: a dull pain in the neck and head lasting for several days, insomnia, exhaustion and an aversion to bright light. He then treats one group with bloodletting, but not the second. He writes that ‘by doing this, I wished to reach a conclusion [on the effectiveness of bloodletting]; and indeed all those of the second group contracted meningitis.’9 Bloodletting, one of the oldest medical practices in the world, dating back to the ancient Egyptians, Babylonians and Greeks, is today known to be harmful to patients and, in the case of meningitis, certainly has no proven benefits. But, in defence of al-Rāzi, we should remember that both Galen and Hippocrates used it, and that physicians would continue to do so until the late nineteenth century. Indeed, the first American President, George Washington, died after being drained of five pints of blood from excessive bloodletting as a treatment for pneumonia. And bloodletting is still used as part of many holistic therapies around the world today, including some in the Islamic world, where it is part of the procedure of ‘cupping’, or hijamah; this despite all the advances in modern medicine that demonstrate its utter ineffectiveness.

  The point of this story is to demonstrate the notion of a control group in a trial, and it emphasizes al-Rāzi’s commitment to empirical medical science. He even took on the great Galen in his excellent al-Shukūk ala Jālīnūs (Doubts About Galen), in which he criticizes the Greek notion of the four humours. Unfortunately, his work was not followed up and the theory of the humours was later brought back into the medical mainstream by Ibn Sīna. It is disappointing to note that these notions are still adhered to by millions of educated secular Westerners as part of alternative medicine. If only al-Rāzi were around today; with the medical knowledge we have, he would be dumbfounded by the prevalence of such ideas, given his passionate condemnation of medical quackery and its dangers. Just because such practices and beliefs go back thousands of years to ancient Greece, or India, or China, does not make them right. Al-Rāzi knew this and had the courage to say so when he discovered that a particular practice did not work. For instance, in his notes he records that he does not agree with Galen’s descriptions of the course of a fever. He rejects the idea, central to the Greek theory of humours, that the body’s temperature is raised or lowered when the patient drinks warm or cold liquids; al-Rāzi realized that a warm drink may raise the temperature of the body higher than the temperature of the liquid itself, suggesting that this rise must be triggering a more complicated physiological response in the patient than the simple transfer of warmth. Nevertheless, al-Rāzi was often reluctant to criticize Galen, since other physicians would often accuse him of arrogance for daring to doubt the great man.