1025
Avicenna’s encyclopedic Canon of Medicine formed a crucial 11th-century bridge in the history of medicine. It brought together the knowledge and theories of Ancient Greek luminaries – largely forgotten in medieval Europe – with the traditions of Persia and India and the best of contemporary medical understanding. The Canon preserved the history of medicine up to that time, but also laid the foundations of modern, experience-based, medical science.
The Canon, more than a million words long, was completed in 1025, and translated into Latin in the 12th century, and into Hebrew a hundred years later. Its compiler was the prodigiously talented and polymathic Avicenna, whose name is the Latin form of ‘Aven Sina’, the Hebrew version of ‘Ibn Sina’ (in full, Abu Ali al-Husayn Ibn Abd Allah Ibn Sina). He was born around 980 near the ancient city of Bukhara, in modern Uzbekistan, and educated by a private tutor. Intellectually precocious, by the age of 18 he was discovering new treatments for disease, and by his early twenties he was personal physician to Sultan Nuh Ibn Mansur al-Samai, of the Persian Samanid dynasty in Bukhara.
Curing the sultan of a dangerous illness led to the young Avicenna being granted access to his rich and extensive library, where he researched and wrote books on science, mathematics, law, and ethics. However, the fall of the Samanids and the death of his father left him a wandering scholar, moving from city to city, and settling briefly in Rai, near modern Tehran, and Qazvin, in northwestern Iran. For a while, in the city of Hamadan in west-central Iran, he was appointed court physician to Prince Shams al-Dawlah of the Buyid dynasty, one of the family that had seized control of the Abbasid Empire in Baghdad. Following his father into government service, he was twice appointed vizier or chief minister.
During this period, Avicenna is believed to have begun work on the three-volume Canon (in Arabic, Al-Qanun fi al-Tibb). In it, the learning of Hippocrates and Aristotle from the 5th and 4th centuries BC co-exists with that of another famous Greek doctor, Galen, from the Roman Empire of the 2nd century AD. Added to them are the writings of Persian and Indian physicians, as well as Avicenna’s own observations and the writings of his contemporaries.
Different sections of the book deal with anatomy, physiology, general pathology and detailed studies of individual diseases, along with descriptions of simple and compound drugs that might be used to cure them. It is a triumph of organization and categorization – for example, Avicenna lists fifteen different types of pain: boring, compressive, corrosive, dull, fatiguing, heavy, incisive, irritant, itching, pricking, relaxing, stabbing, tearing, tense and throbbing. But the breadth of his references and the detail of his understanding were matched by a resolutely practical interest in surgery and the application of medical knowledge. For example, among the procedures spelled out were clearing out the airways with a length of reed wrapped in soft material to assist breathing, inserting a tube – ‘gold or silver’, he insisted – into the pharynx, or, as a last resort, performing a tracheotomy to allow air to reach the lungs.
Avicenna recommended techniques for anaesthetizing patients and relieving pain, including the use of mandrake root or opium – not more than two grains, or a dose the size of a large lentil, he says – taken orally to bring about sleep before the amputation of a limb or the excision of a cancerous tumour (another surgical procedure that he proposed). Opium, he suggested, could also be used locally for pain relief.
Many of the herbs that he recommended for their curative properties had not been used in medicine before. Avicenna suggests that wounds should be washed in wine, implying that he understood the antiseptic effects of alcohol, and he set out rules for the testing of medicines, including the need for purity, blind testing and close observation of timings and results. The Canon was also one of the first surviving medical texts to suggest that the pulse was caused by the beating of the heart, and Avicenna proposed checking a patient’s pulse rate by feeling his wrist. He was said to be able to diagnose certain diseases solely by using this method.
Although the learning of ancient times was largely forgotten or ignored in the Europe of Avicenna’s day, in the Arab world the study of Ancient Greek, Persian, and Indian medicine was already well established. Scholars at the famous philosophical and medical school at Gundishapur, in southern Iran, studied Greek texts translated into Arabic, Syriac and other Middle Eastern languages by monks from Byzantium and Alexandria centuries earlier. The Canon of Medicine was the first book to bring together all these different sources of medical knowledge, and it became the most widely used and comprehensive work on medicine during the Middle Ages, both in Europe and in the Arab world. It was clear, concise, and authoritative, and it gave ready guidelines to which doctors could refer in treating disease.
In some respects, and despite his innovations, Avicenna’s acceptance of the wisdom of the past perpetuated medical red herrings. He did not question such fundamental theories as the belief in the four bodily ‘humours’ of blood, yellow bile, black bile, and phlegm, representing air, fire, earth and water respectively, whose imbalances in the body he believed to be responsible for most sickness. Indeed, partly through his authority, this belief became the bedrock of later medieval medicine. But his actual observations were acute and his remedies as reliable as any to be found in his day – and his recommendation of experience, observation and practical experimentation as the basis of progress justifies the reputation of the Canon as one of the original texts of medical science.
The Canon of Medicine was the first book of medicine to base its theories on evidence and objective experimentation. These extracts demonstrate both the conservatism of his philosophy and the radicalism of his medical treatments.
Natural philosophy speaks of four elements, and no more. The physician must accept this. Two are light, and two are heavy. The lighter elements are Fire and Air; the heavier are Earth and Water.
Light: equivalents: weak, male (because conferring or inceptive), positive, active. Heaven.
Heavy: equivalents: strong, female (because recipient), negative, passive. Earth …
… There are three groups of agents which alleviate pain: (i) Some contrary to the cause of pain, which removes the cause, e.g. Anethum, linseed, made into a poultice and applied over the painful place; (ii) any agent which counteracts the acrimony of the humours, or soothes, induces sleep, or dulls or soothes the sensitive faculties and lessens their activity, e.g. inebriants, milk, oil, aqua dulcis, etc.; (iii) an agent which infrigidates as dulls the sensation in the painful part, e.g. all narcotics and somniferous drugs. The first of the three is the most certain.
CANON OF MEDICINE, BOOK I, PP. 34 AND 251, TRANSLATED BY O. CAMERON GRUNER
With the invention of the printing press in Europe in the 15th century, the book spread across the continent, and its Latin version was reissued 16 times between 1470 and 1500, going through another 20 editions in the hundred years thereafter. Added to, commented on, and revised by generations of scholars, it remained one of the most influential textbooks in the medical schools of Europe well into the 17th century.
As for Avicenna himself, his later years saw prolific work but also imprisonment and exile. As he was writing the Canon he was also working on another literary triumph, the mammoth scientific and philosophical Kitab al-shifa, or Book of Healing. The death of Shams al-Dawlah in 1022, however, meant that Avicenna was briefly imprisoned and then forced into exile. He took refuge in Isfahan, in central Iran, where he spent the remaining 15 years of his life. Here, honoured at the court of Ala al-Dawlah, he completed his two great books. He also composed an account of his own philosophical development, the Kitab al-isharat wa al-tanbihat (Book of Instructions and Words), a summary of the Kitab al-shifa, and over 200 short treatises on various philosophical and scientific subjects, as well as books now lost. He died in 1037, accompanying the ruler on a military campaign against the town of Hamadan, where he had once lived. With a posthumous reputation as one of the greatest philosophers of medieval Islam, his tomb is still venerated there today.