Ibn al-Nafis and the Lesser Circulation

Ibn al-Nafis (Ala al-Din Abu al-Hasan Ali ibn Abi al-Hazm al-Qurashi al-Dimashqi, c. 1213-1288) was a physician trained at the great Nuri hospital of Damascus who became one of the foremost medical men of his age, working later as a chief physician in Cairo. In his commentary on the anatomy of Ibn Sina's Canon, written when he was a young man around the 1240s, he set down, by careful reasoning about the structure of the heart, a discovery that would not be matched in Europe for some three centuries: that the blood does not pass from the right chamber of the heart to the left through pores in the thick wall between them, as the ancients Galen and Ibn Sina had supposed, for that wall is solid; rather it goes out from the right chamber to the lungs, where it mingles with the air and is refined, and returns to the left chamber. This is the lesser, or pulmonary, circulation of the blood. He also reasoned that the heart is nourished by vessels running through its own substance and questioned other received doctrines, insisting that anatomy be judged by observation and reason and not by the authority of the ancients alone. Ibn al-Nafis was besides a master of the religious sciences and the law, a man of the Shafi'i school, and he wrote on many subjects; his medical encyclopaedia was vast. His work was pursued in the bimaristans, the hospitals of the Islamic city, with their wards, pharmacies and teaching, institutions of charity and learning that were among the glories of the age. This scene depicts a physician's study in such a hospital in Ayyubid Damascus, with the anatomical diagram of the heart and lungs and the great books of medicine open upon the desk. In keeping with the project's ethics any figure is anonymous and at a distance.