Ibn Sina (Avicenna) (973-1037):
On Medicine, c. 1020 CE
Avicenna (973-1037) was a sort of universal genius, known first as a physician. To
his works on medicine he afterward added religious tracts, poems, works on philosophy, on
logic, as physics, on mathematics, and on astronomy. He was also a statesman and a
soldier, and he is said to have died of debauchery.
Medicine considers the human body as to the means by which it is cured and by which it
is driven away from health. The knowledge of anything, since all things have causes, is
not acquired or complete unless it is known by its causes. Therefore in medicine we ought
to know the causes of sickness and health. And because health and sickness and their
causes are sometimes manifest, and sometimes hidden and not to be comprehended except by
the study of symptoms, we must also study the symptoms of health and disease. Now it is
established in the sciences that no knowledge is acquired save through the study of its
causes and beginnings, if it has had causes and beginnings; nor completed except by
knowledge of its accidents and accompanying essentials. Of these causes there are four
kinds: material, efficient, formal, and final.
Material causes, on which health and sickness depend, are--- the affected member, which
is the immediate subject, and the humors; and in these are the elements. And these two are
subjects that, according to their mixing together, alter. In the composition and
alteration of the substance which is thus composed, a certain unity is attained.
Efficient causes are the causes changing and preserving the conditions of the human
body; as airs, and what are united with them; and evacuation and retention; and districts
and cities, and habitable places, and what are united with them; and changes in age and
diversities in it, and in races and arts and manners, and bodily and animate movings and
restings, and sleepings and wakings on account of them; and in things which befall the
human body when they touch it, and are either in accordance or at variance with nature.
Formal causes are physical constitutions, and combinations and virtues which result
from them. Final causes are operations. And in the science of operations lies the science
of virtues, as we have set forth. These are the subjects of the doctrine of medicine;
whence one inquires concerning the disease and curing of the human body. One ought to
attain perfection in this research; namely, how health may be preserved and sickness
cured. And the causes of this kind are rules in eating and drinking, and the choice of
air, and the measure of exercise and rest; and doctoring with medicines and doctoring with
the hands. All this with physicians is according to three species: the well, the sick, and
the medium of whom we have spoken.
From: Charles F. Horne, ed., The Sacred Books and Early Literature of the East, (New York: Parke, Austin, & Lipscomb, 1917), Vol. VI: Medieval Arabia, pp.
Scanned by Jerome S. Arkenberg, Cal. State Fullerton. The text has been modernized by
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