The Significance of Ibn Sina's Canon of Medicine in the Arab and Western worlds

Overview

Ibn Sina, (980-1037), whose name was Abu al-Hussayn ibn Abdullah ibn Sina, was an outstanding medical writer and physician. His Al-Quanun fi al-Tibb, was a masterpiece of Arabic systemization, in which he sought to collate and organize all known medical knowledge. When the work was translated into Latin, it became known as the Canon of Medicine and was the dominant text for the teaching of medicine in Europe. It went through many versions and was later translated into the vernacular of several nations. The Canon was used as a medical text for over 800 years, continuing in some areas until well into the nineteenth century.

Background

The prophet Muhammad, born at Mecca in 570, created a religion—Islam—that quickly spread and unified the tribal people of the Arabian peninsula. Mohammed recorded his beliefs in the Koran, the holy book of Islam. He was concerned with health and addressed many issues in his writings. During the seventh and eighth centuries, Islam spread eastward and north into regions as far away as parts of the future Soviet Union. Dynasties of rulers held various kingdoms of Islamic influence. In the area that is presently Uzbekistan, the Samanid princes developed a strong empire with a distinguished court and extensive library of Greek writings and other texts. Ibn Sina was born in this environment in the tenth century.

Impact

Ibn Sina was to the Arab world what Aristotle (384-322 b.c.) was to ancient Greece. He was a scholar not only in medicine but in law, mathematics, physics, and philosophy. The name Avicenna, as he was known in Europe, is a Latinized form of his Arabic name.

Born in Bukhura, in what is now Uzbekistan, Ibn Sina had memorized the complete Koran by the time he was 10. He was 16 when he decided to turn to medicine, which he found very appealing and quite easy. While in his teens he knew enough about medicine to treat the sick Samanid ruler, Nuh ibn Mansur. This gave him what he wanted—access to the royal library, which had a large collection of Greek philosophy and sciences. At age 20 he was appointed court physician and traveled widely, but somehow found the time to write 20 books in other fields and 20 on medicine. After traveling to several places and meeting famous contemporaries, he moved to Hamadan in present-day Iran and completed many monumental writings. His Kitab al-Shifa (The book of healing) is a medical and philosophical encyclopedia.

His great work, the Canon of Medicine was written before his twenty-first birthday. At more than one million words long, it represents a comprehensive collection of all existing medical knowledge during his time. He summarized Hippocrates (460-377 b.c.), Galen (130-200), Dioscorides (40-90), and late-Alexandrian physicians, adding Syro-Arab and Indo-Persian knowledge along with his own notes and observations. He tried to put anatomy, physiology, diagnosis, and treatment into proper categories. The work is not only a systematic digest of all medical information, but is clearly arranged, organized, and written. As a result, Ibn Sina's work became preferred to those of Rhazes (865-923), Ali ibn Abbas Maliki, and even Galen.

The five books of the Canon of Medicine are organized with summaries and comments. Book One begins with the general principles of humors. Ibn Sina elaborates on the versatility of the humoral theory and how it fits into the four elements, four ages of man, and the four temperaments. He then moves on to anatomy, physiology, hygiene, etiology (the origin of diseases), and symptoms and treatments of disease.

Book Two deals with materia medica, or pharmaceuticals. He details all known information on the physical properties of simple drugs and discusses how to collect and preserve herbals. In a separate section he lists 740 different types of medicinals.

Book Three zeroes in on specific diseases that he catalogs from head to toe. He outlines the etiology, symptoms, diagnosis, prognosis, and treatment of each one of these diseases.

Book Four tackles conditions that affect the entire body, including fevers, infections, ulcers, abscesses, pustules, fractures, and injuries. Avicenna also discusses poisons and includes a section on anorexia and obesity.

Book Five ends with a discussion of compound drugs, using terms like theriacs, electuaries, emetics, pessaries, and liniments, along with their medical uses.

In its basic conception the Canon follows Galen in the ancient tradition of elements and humors. The elements are air, water, fire, and earth. The theory of the four humors includes blood, phlegm, choler or yellow bile, and melancholy or black bile. However, Ibn Sina incorporated many observations not found in Galen's.

Ibn Sina's original contributions recognized the contagious nature of phthsis and tuberculosis, the distribution of diseases through soil and water, and the interaction of mind and body. He suggested a treatment for lacrymal fistula and introduced a medical probe for the channel.

He also stressed the importance of prevention. Discussing diet and the influence of climate and environmental factors on health, the book also discusses rabies, hydrocele, breast cancer, tumor, labor, and treatments for poisons. He showed the difference between meningitis and the meningismus of other acute diseases. Other conditions he described include chronic nephritis, facial paralyses, ulcer of the stomach, and types of hepatitis and their causes. He discussed in great length the dilation and contraction of the pupils and how they were used in diagnosis, as well as the six motor muscles of the eye and the function of the tear ducts. Noting the contagious nature of some diseases, he attributed this to "traces" left in the air by the sick person.

In addition to a description of 740 medicinal plants and drugs made from them, he laid out a series of basic rules for clinical drug trials, many of which continue to serve as the basis of modern clinical trials. Ibn Sina stipulated that: 1) The drug must be pure and must not have anything that would lessen the quality; 2) The drug must be used on a "simple" disease, not one with several complications (Today, this is called targeted treatment); 3) The drug must be tested on at least two different types of diseases, as sometimes a drug cures one disease by the essential quality and cures another by accident (Ibn Sina was proposing the parameters for a controlled experiment); 4) The quality of the drug must correspond with the strength of the disease (This is based on the Greek view that the "heat" of some drugs is less than the "coldness" of certain diseases, so they would not have an effect on them); 5) The observation of the time must be recorded so as not to confuse with natural healing; 6) Several trials must be made and the effect of the drug deemed to be consistent, otherwise the effect may be considered an accident; 7) While animal testing on a lion or horse may begin the experiment, it must be tested on the human body, as reactions on an animal may not be the same as the effect on man.

Ibn Sina encouraged observation and a close study of the human body; he condemned conjecture and presumption in anatomy. Some of his observations were ahead of his time. For example, he observed that the aorta, at its origin, contains three valves that open as blood rushes into it from the heart during contraction and closes during relaxation so the blood may go back into the heart. He determined that muscles could move because of nerves and that pain in the muscles is also due to nerves. He found that the liver, spleen, and kidney do not contain nerves, but that nerves are present in the coverings of these organs.

The Canon was translated into Latin as early as the twelfth century by Gerard of Cremona (1114-1187) and published in Venice in 1493-1495. The Canon became a standard textbook for medical education in the emerging medical schools of Europe. The fact that it was reissued 16 times in the last 30 years of the fifteenth century underscores its influence; 15 editions were in Latin and one in Hebrew. During the sixteenth century, it was revised more than 20 times. In 1390 Cameron Gruner translated part of the book into English as "A Treatise on the Canons of Medicine of Avicenna." From the twelfth to the seventeenth centuries the Canon was the chief guide to medical science in the West. As the great medical scholar William Osler (1849-1919) noted, the Canon has remained a medical bible for longer period than any other work.

Although some of the science of the elements and humors are no longer accepted, the contributions of Ibn Sina have helped set the standard for current medical practice. His encouragement of observation is one of the basic tenets of the scientific process, his description of the anatomy and some of the muscles of the eye are still used, and his advocacy of trial and control in drug testing forms the basis of modern pharmacological discovery.

Ibn Sina and his Canon of Medicine has become so important that no discussion on the history of medicine can be complete without referring to him. He has earned many honorary titles, notably the "Galen of Islam." His preeminence in the Latin West was even enshrined by Dante (1265-1321), the fourteenth-century Italian poet, who ranked Ibn Sina between Hippocrates and Galen.

Nevertheless, some critics have alleged that Ibn Sina stifled independent thought through his writings. However, some of his treatises and comments are highly critical of the works of past writers, opening the door for subsequent physicians to question his own writings and those of other scientific authorities.

EVELYN B. KELLY

Further Reading

Clendening, Logan. Source Book of Medical History. Dover: Henry Schuman, 1942.

Khan, Muhammed Salim. Islamic Medicine. London: Routledge & Kegan Paul, 1986.

Porter, Roy. The Greatest Benefit to Mankind: A Medical History of Humanity. New York: W.W. Norton, 1997.

Pouchelle, Marie-Christine. The Body and Surgery in the Middle Ages. New Brunswick, NJ: Rutgers University Press, 1990.