al-ʻIlm ʻilman: ʻilm al-adyan wa-ʻilm al-abdan,” (Science is of two kinds: One attends to the soul, the other attends to the body) 

This saying is sometimes attributed to the Prophet Muhammad and sometimes to al-Imam al-Shafiʻi.

Galen, Kitāb Jālīnūs fī 'amal al-tashrīh (On anatomical procedures), circa 15001599, Yale University Library

The rituals of Islam pay much attention to the health of believers. Not only is ablution obligatory for the five daily prayers, but priority also is given to general health. Believers were encouraged to seek medical help by following the example of the Prophet himself, who did not refrain from consulting his own physician, al-Harith ibn Kalada (died 670), or from sending his immediate companions to seek his medical help when they were sick. This al-Harith was apparently a relative of the Prophet. He did not readily convert to Islam, and yet Muhammad saw no harm in consulting him on medical questions. This very precedent was later used in Islamic jurisprudence to justify the consultation of non-Muslims in matters of medicine. It may also help to explain the ubiquitous presence of Jewish and Christian physicians at the highest ranks of the caliphs’ courts throughout Islamic history.

The Prophet himself made several statements that had medical implications, such as his favoring the daily consumption of some honey, and his advice to the effect that whoever ate honey in the morning at least three days a month would suffer no grave illness. He also recommended the use of olive oil both for food and for ointment. A good number of those prophetic pronouncements later were collected in special types of texts, called prophetic medicine, which have always enjoyed great popularity.

As was the case with the genre of anwaʼ writings (the folk astronomical literature that was known in pre-Islamic Arabia), later replaced by more scientific astronomy, so probably with medical pronouncements that were sometimes attributed to the Prophet or to his companions—they probably all derived from some form of folk medicine also prevalent in pre-Islamic Arabia. And like the anwaʼ literature, the folk medical literature also came to be replaced by the more "scientific" medicine that was brought into Islamic civilization, first from Syriac, Persian, and Sanskrit texts, and later from ancient Greek texts.


Abu Bakr Muhammad ibn Zakariya al-Razi, Kitāb al-Ḥāwī fi al-ṭibb (The comprehensive book on medicine), circa 1674, Yale University Library

Just as with "scientific" astronomy, the imported "foreign" medicine began to gain a hegemonic status as soon as it was introduced into Islamic culture. It appears in early Islamic times in two types of sources. Some resembled “medical recipes” and derived mostly from Indian medical literature; others were of the more "scientific" philosophical type, derived mainly from Greek medical literature and especially from the translations of the Greek works of Hippocrates (died circa 377 BC) and Galen (died circa 200 AD).

The latter type of medical text, and especially the work of Galen, was heavily influenced by the Aristotelian philosophical worldview. Nevertheless, much of the later Greek medicine had a folk aspect to it as well and apparently was widely circulated in pre-Islamic Arabia and in other regions to the north―as documented in Syriac written sources that have survived from the pre-Islamic eastern Mediterranean region. Some of that Greek folk medical knowledge must have mixed with ancient Arabian medicine before the advent of Islam and formed part of the common folk repertoire of medicine. Evidence for such a development comes from some pronouncements that were recorded in 13th-century biographical sources, and which were attributed to the same physician and relative of the Prophet, al-Harith ibn Kalada. Those pronouncements refle knowledge of the Greek philosophical presuppositions about the nature of the biles and humors of the body, at a time when no formal translations of the more scientific Greek texts into Arabic had even begun.

Once the Greek medical literature was made available in Arabic, however, after the extensive translations of the eighth and ninth centuries, the same trends that were noticeable in the Greek corpus began to take shape in the newly emerging Islamic society. Physicians, who could easily distinguish the clinical approach of Hippocrates in contradistinction to the more philosophical analytical approach of Galen, could appreciate the virtues of each approach and tried to model themselves after those famous Greek physicians. A few centuries later, calling a physician "the Galen of his age" became the highest form of praise a doctor in the Islamic world could possibly attain, irrespective of his religious, ethnic, or geographical background.


Abu Bakr Muhammad ibn Zakariya al-Razi (also known by the Latin form of his name, Rhazes or Rasis), Continens Liber (The virtuous life), 1529, Qatar National Library

Physicians such as Abu Bakr Muhammad ibn Zakariya al-Razi (Latinized as Rhazes, 865‒925) with an unusual gift for clinical observations were in their time likened to Hippocrates. This comparison was made mainly because of the extensive clinical records that were kept by al-Razi, and which have survived the ravages of time. His multivolume work Kitāb al-Ḥāwī fi al-ṭibb (The comprehensive book on medicine, also known in Latin as Continens Liber and in English as The Virtuous Life) is in fact incomplete, and yet it contained the most extensive record of clinical cases that any medieval physician ever assembled.

Al-Razi’s excellence in clinical medicine should not be taken to mean that he was incapable of analytical philosophical reasoning. In fact, he was also famed as a philosopher in his own right and at times suspected of being a free thinker in matters of religion. Some of his philosophical writings have survived and clearly attest to his acumen in philosophy as well as medicine.

Perhaps it was al-Razi's combined analytical and observational talents that rendered him capable of noticing things that had escaped the attention of even the smartest of the previous Greek physicians. The most famous observation that has earned him a major place in medical history was the one in which he detailed the clinical differences between two diseases: smallpox and measles. Al-Razi’s independent treatise on the subject remained the standard reference up to modern times. It was even printed, in both the original Arabic and the Latin translation on facing pages, in London as late as the middle of the 18th century.

Al-Razi's more important critical work, al-Shukūk 'ala Jalīnus (Doubts regarding Galen), which demonstrated his analytical abilities in marshaling together his philosophical and medical knowledge, important as it is from the perspective of intellectual history, remained little studied in Islamic times. His book and the similar work by Ibn al-Haytham (also called Alhazen, 965‒1039), al-Shukūk 'ala Baṭlamyūs (Doubts regarding Ptolemy), were only published in modern times, during the latter half of the 20th century, and there is little evidence that they were used extensively in medieval times. Neither of them was ever translated into Latin, for example, despite the fact that other works of both authors circulated in Latin and some of them were translated more than once. The relative neglect of those critical authors remains a mystery until this day but certainly promises to reward any researcher who cares to unlock its secrets.

Influences on the West


Abu ʻAli al-Husayn Ibn Sina (also known by the Latin form of his name, Avicenna), al-Qanūn fī al-ṭibb (The canon of medicine), circa 18th century, Wellcome Library

Other physicians of the Islamic world, such as Abu 'Ali al-Husayn ibn ‘Abd Allah Ibn Sina (Latinized as Avicenna, 980‒1037), were much more influential both in the Islamic world and in the West, probably because of their more conventional philosophical bent. And hence they could explain the specific behavior of a disease as well as relate it to the general constitution of the body, of course as that constitution was proscribed by the Aristotelian worldview. Ibn Sina’s two major works, which were translated several times into Latin, were both encyclopedic in nature.

His al-Qanūn fī al-ṭibb (Canon of medicine, or Canon for short) was first translated into Latin during the Middle Ages and again during the European Renaissance. The importance of the Canon was not that it contained some previously unnoticed critical medical observation, as was the case with al-Razi, but that it managed to digest the whole extensive corpus of Galenic medicine and to reproduce it in an intelligently edited and rearranged format, thus making it an ideal textbook for medical students. It was in fact used in that capacity throughout European medical schools well into the 18th century if not later, and in the private tutoring of Eastern physicians until this day. That its value was well appreciated by European scientists during the Renaissance is succinctly attested to by the statement of the Renaissance polymath Guillaume Postel (151081), who once said that Avicenna "says more on one or two pages than does Galen in five or six large volumes." Only a few years after Postel's death, the Florentine Medici Oriental Press printed the Arabic original of Avicenna's Canon in 1593, hoping firstly to sell it to medical students all over Europe, and only secondarily to export it to the Islamic world.

In a twist of fate, it was the Medici edition that was reprinted at the Bulaq Press in Egypt during the 19th century. It still forms the base copy for most, if not all, of the currently circulating offset-printed Arabic texts of the Canon in the modern Arab and Islamic worlds.


Muhammad ibn Ahmed ibn Rushd (also known by the Latin form of his name, Averroes), Libri tres de anima (Three books on the soul), 1521, Qatar National Library

Muhammad ibn Ahmed Rushd, Kitāb al-Dhakhīrah fī ʻilm al-ṭibb (A treasury of medicine), circa 16th century, Yale University Library

Avicenna's philosophical works, mainly his great encyclopedia, al-Shifa' (The healing), which contained most of his other scientific works, including large sections on mathematics, astronomy, and physics, shared the brilliant reputation of his medical encyclopedia. This work too was retranslated during the Renaissance by the indefatigable Venetian physician Andrea Alpago (died circa 1521), who also translated the medical works of Avicenna as well as the works of Avicenna's commentators. Alpago had traveled to Damascus in 1486 to replace another Venetian physician by the name of Girolamo Ramusio, who had died in 1486 in Beirut on his way back to Venice. Alpago's lived in Damascus and served as the physician of the Venetian consulate in the city, which offered him the golden opportunity to improve his Arabic and to undertake such massive projects as making the philosophical and medical works of Avicenna available to the Latin West. Both his life and that of Ramusio still await the attention of modern scholarship.

As most of Avicenna's philosophical writings were in fact restatements of the Aristotelian philosophical doctrines, with some modifications here and there in important places, they were destined to play a very important role in the introduction of Aristotelian thought to Renaissance Europe. This happened in much the same way with the Latin translations of Avicenna's successor and most famous Aristotelian commentator, Muhammad ibn Ahmed ibn Rushd (also known by the Latinized version of his name, Averroes, 1126‒98). Together, Avicenna and Averroes barely left a single Aristotelian text undigested or without comment. By their combined efforts, the Islamic acculturation of Aristotle was duly made available to Renaissance men and women in their Latin language.

The most important influence Avicenna had on the Latin West, however, was undoubtedly through his medical work the Canon. It made such an impression on European medical faculty that a dean of the Academia Nassauensis (Herborn Academy, in present-day west-central Germany), Zacharias Rosenbach (1595‒1638), attempted to introduce the learning of Arabic into that academy specifically so that students could consult Avicenna's works in the original.


ʻAli Ibn Abi al-Hazm Ibn al-Nafis, al-Mūjiz fī al-ṭibb (Epitome of medicine), circa 1551–1850, Wellcome Library


The fate of Avicenna's commentator, Ibn al-Nafis (circa 1210‒88) of Damascus and Cairo, had a much more intriguing effect on European science. While trying to explain the Canon of Avicenna around the year 1241, especially the section on anatomy, which reflected the Galenic vision of the human body, Ibn al-Nafis noticed that both Galen and Avicenna stipulated that the function of the human heart was to cleanse the blood by injecting into it the vital spirit, the Greek pneuma. The blood intermixed with the pneuma in the left ventricle of the heart after having passed from the right ventricle through a hole between the two ventricles. It was at that point that Ibn al-Nafis made his most constructive criticism of his predecessors by asserting that there was no such hole between the two ventricles.

The only way the blood could be cleansed, Ibn al-Nafis asserted, was for it to be passed from the right ventricle to the lungs. Thus he introduced the concept of the pulmonary or smaller circulation of the blood, which after mingling with air in the lungs passed from the lungs back to the left ventricle directly, where it would receive the Galenic pneuma.


Dioscorides Pedanius of Anazarbos, Kitāb Disqūrīdis (Dioscorides’s book), circa 1100‒1200, National Library of France

Andrea Alpago, who translated parts of Ibn al-Nafis's work, must have known of such an important departure from the Avicennan-Galenic tradition. In fact, he may have inserted comments about criticism of the Galenic teaching on the heart into his translation of al-Nafis’s work. These comments obviously should be investigated in connection with Ibn al-Nafis's own objections on the same subject. Alpago may even have lectured on this topic at the medical school of Padua, where he returned in 1505, after his sojourn in Damascus, to take up the chair in medicine. His lecture notes as well as his translation of Ibn al-Nafis's work have not been investigated by modern scholars; thus it remains uncertain whether Alpago himself was the conduit by which the ideas of Ibn al-Nafis entered the Paduan medical community.

We do know, however, that some form of transmission must have happened, for the same information, without attribution to Ibn al-Nafis as far as can be told, was also asserted later, first by Michael Servetus (circa 1511‒33) and then by Realdo Colombo (1516‒59). It was eventually formalized and re-articulated by the British physician William Harvey (1578‒1657), to whom the minor circulation of the blood is usually attributed in the modern literature. Harvey did in fact undertake his advanced medical studies at the University of Padua, graduating with honors in 1602, almost a full century after Alpago's assumption of the chair of medicine at the same institution.


Abu al-Qasim Khalaf Ibn Abbas al-Zahrawi (also known by the Latin form of his name, Albucasis), Liber theoricae nec non practicae Alsaharavii (Theoretical and practical book by al-Zahrawi), Augsburg, 1519, Qatar National Library

In the same vein of criticism of the Galenic works, and independently of the works of Avicenna, there was of course the work of al-Razi, already mentioned.

The related field of pharmacology took root in the Islamic civilization through translations of the most famous Greek herbal, the work by Dioscorides of Anazarbus (active in the first century), commonly known as De Materia Medica. Knowledge of Dioscorides must have been intertwined with the folk tradition of herbals, as exemplified in works on plants by such people as ʻAbd al-Malik al-Asmaʻi (740‒circa 828), Abu Hanifa al-Dinawari (died circa 895), and later Abu al-Rayhan al-Biruni (also known by the Latinized name Alberonius, 973‒1048) in his Kitab al-saydana (Book on pharmacology), although the latter included some descriptions of medicines as well. Al-Asmaʻi and al-Dinawari gave full descriptions of plants, but more in the lexical tradition, a more limited offering compared to the writing of Dioscorides. 


ʻAli Ibn al-Abbas al-Majusi (also known by the Latin form of his name, Haly Abbas), Kitāb Kāmil al-ṣināʻah al-ṭibbīyah: al-maʻrūf bi-al-Malaki (The complete art of medicine), 1437–38, Yale University Library

In the latter, the medicinal qualities of the plants were much more emphasized; in some instances, what we now would call their side effects even were included. Lexical items were important to Dioscorides, just as they were to al-Biruni. As in the encyclopedia of Dioscorides, almost all plants in al-Biruni's Kitab al-saydana have names that were gathered from the languages of the several regions where the book was expected to be read. Similarly, the second treatise (on causes and symptoms) of Avicenna's Canon as well as other encyclopedic works, such as those of al-Razi, Ali ibn al-Abbas al-Majusi (also known by the Latinized name Haly Abbas, died 994), and Abu al-Qasim Khalaf ibn al-Abbas al-Zahrawi (Latinized name Albucasis, circa 936‒1013), all of which were translated into Latin, also contained whole sections devoted to pharmacology. They were mainly culled from the works of Galen and Dioscorides, however, and did not rely as heavily on the folkloric traditions of the Arabs.

As with other scientific fields that developed in Islamic civilization, pharmacology benefited from this unintended marriage between the newly available Greek scientific material and local folk knowledge. Starting in the ninth century with the translations of the text of Dioscorides containing the names of fewer than 900 plant and animal drugs, the field grew, so that during the heyday of Islamic civilization, one of the most famous Arabic encyclopedias of pharmacology, the Kitāb al-jāmiʻ li-mufradāt al-adwiyah wa-al-aghdhiyah (Compendium on simple medicaments and foods) by Ibn al-Baytar (died 1248), contained more than twice that number of medicines.

Referenced Items

  1. The Book of Medicinal and Nutritional Terms
  2. The Book of Times
  3. The Lights of the Stars
  4. The Elucidation of the Memoir on Astronomy by Ṭūsi
  5. Three Books on the Soul
  6. New Methods in Medicine
  7. Theoretical and Practical Book by Al-Zahrawi
  8. The Comprehensive Book on Medicine