Ibn Rushd on Anatomy
By SAHIN, A.
Ibn
Rushd was one of the greatest intellectual geniuses in human history. He was
acquainted with all the sciences of his time and an authority in several of them-philosophy,
jurisprudence, astronomy, and medicine. He became known in Europe under the name
of Averroes, in particular for his brilliant commentaries on Aristotle which
shaped European thinking throughout the later Medieval and early Renaissance
periods. Here, we shall be reflecting mainly on his contribution to the study of
human anatomy.
He was born in Cordova in 52OAH (1126) and named after his grandfather Abu al-Walid
Muhammad ibn Ahmad ibn Rushd, who died in the same year. His grandfather was the
Chief Judge in Cordova and the foremost authority in Maliki jurisprudence. To
distinguish him from his illustrious ancestor, Ibn Rushd was later known as Ibn
Rushd al-Hafid (the grandson).
Cordova, where Ibn Rushd grew up, was a thriving centre of all the diverse arts
of civilization and culture attracting many great scholars from around the then
known world to its wonderful libraries. Ibn Rushd studied and memorized the
Qur’an and the Muwatta of Imam Malik. He was an excellent student of
jurisprudence and quickly qualified to give legal opinions and sit as judge.
Following his work in the sciences of law, language and Hadith, he went on to
study mathematics, astronomy and astrology and then medicine. He was a friend to
the most prominent thinkers and writers of his age: Ibn al-Tufayl (d. 1186/6),
author of the famous allegory Hayy ibn Yaqzan (said to have influenced Robinson
Crusoe ); the philosopher, Ibn Bajja (Avempace in the West, d. 1139); the great
jurist and judge Abu Bakr ibn al ‘Arabi (d. l148); the famous physician Abu
Marwan ‘Abd al-Malik ibn Zuhr (Avenzoar in the West, d. 1161) and his son Abu
Bakr (d. 1198).
Ibn
Rushd served as a judge in Ishbiliya (Seville) in 1171 and then in Cordova two
years later. His reputation for wide knowledge, correctness and fairness in
giving verdicts, led to his appointment as Chief Judge. His book Bidayat al-mujtahid
wa nihayat al-muqtasid (The reference for the searcher and the resort for the
fair) remains an important reference for students of jurisprudence and is still
taught in universities to this day. Although he was a Maliki he used the ideas
of other schools of thought. Because he had so many activities and interests
besides his public duties, Ibn Rushd had to organize his time very fully: he
spent his days working as a judge, teaching, and in academic discussion with
other scholars; he reserved his nights for reading and writing.
His friend Ibn al-Tufayl wrote to invite him to visit Marrakech, the capital of
the Muwahhidun (Almohades) who had established a powerful and stable state in
North Africa after they took over from the Murabitun (Almoravides), and were
famous for their patronage of scientists, physicians, theologians and
philosophers. Ibn Rushd’s intelligence, learning and ideas so impressed the
ruler, Abu Yusuf ‘Abd al-Mu’min, that he was appointed to reform the
educational system. This he did successfully before returning to Cordova.
When Abu Ya‘qub ibn ‘Abd al-Mu’min came to power, he appointed Ibn Rushd as his
personal physician after Ibn Tufayl. Ibn Rushd held this post for a year (1183)
when he was appointed as Chief judge. His success provoked court envy and he was
falsely accused of heresy, in particular that he adhered too closely to the
doctrines of Aristotle. He was indeed a supporter of Aristotle’s doctrines after
these were properly reformed and adapted to Islam. Ibn Rushd fell out of favour
at the court and was ill-treated. His books on philosophy were burnt, though his
works on medicine and theology were not censored. When Abu Ya‘qub discovered he
had been misinformed, he tried to invite Ibn Rushd back to apologise to him, but
he was too late. Ibn Rushd died on 9th Safar 595AH (December 1198).
His
writings
Ibn Rushd was broadly cultured indeed and wrote on many different subjects. Here
we can mention only the most famous of his great works. In jurisprudence, as
noted above, he wrote Bidayat al-mujtahid wa nihayat al-muqtasid (The reference
for the searcher and the resort for the fair). In philosophy, he wrote Tahafut
al-tahafut (refutation of the refutation), his response to Imam al-Ghazali’s
famous Tahafut al-falsafa (refutation of philosophy). Ibn Rushd combined both
philosophy and religion in mainly two books: Fasl al-maqal wa taqrib ma bayna l-shari‘a
wa l-hikma min al-ittisal (an authoritative treatise on the convergence between
the religious law and philosophy), and Kitab al-kashf ‘an manahij al-adilla fi
‘aqa’id al-milla wa ta‘rif ma waqa‘a fiha bi hasb al-ta‘wil min al-subah al-muzayyifa
wa 1-bida‘ al-mudilla (an exposition of the methodology of demonstrating the
creeds and description of the confusions and innovations in interpretation which
confound truth and lead to error). In medicine, Ibn Rushd wrote the Kitab al-kulliyyat
fi al-tibb (a general reference on medicine) which was translated into Latin and
Hebrew and European vernaculars. It was a major reference in medicine though it
never reached the standard of al-Qanun fi al-Tibb of Ibn Sina (Avicenna, d.
1037) which was used everywhere as simply T he Canon of Medicine.
Ibn Rushd had prepared this book especially for practising physicians and
students of medicine. He apologised for the work’s brevity, a limitation he
attributed to his preoccupation with commitments to judging, political affairs
and philosophy. He advised those who sought greater detail to consult al-Taysir
(The simplification) of Abu Marwan ‘Abd Al-Malik ibn Zuhr. Al-Kulliyyat is
organized under seven broad headings or chapters:
1 Anatomy
2 The function of the organs
3 Diseases (pathology)
4 Syndromes: a brief clinical review
5 Health care, especially sports, massage and sleep
6 Medication and diet
7 Healing (particularly of different types of fevers).
The
chapter on anatomy in al-Kulliyat
Ibn Rushd criticized the physicians and students of medicine of his time for
neglecting anatomy. His own presentation of the subject is both concise and
precise. He divides it into two major areas:
a. Anatomy of ‘simple’ organs such as bones, flesh, and veins.
b. Anatomy of ‘compound’ organs—for example, the arm which comprises bones,
flesh, veins, tendons, nerves etc.
His description starts with the bones of the head and the teeth.
Bones
There are six bones in the cranium and 14 in the upper jaw (the maxilla) and the
ear, and two in the lower jaw (the mandible). All these bones are attached by
seams except the two bones of the mandible that are articulately joined. This
was later established as untrue—the mandible in fact has a single bone not two.
The first to discover this was the physician and linguist ‘Abd al-Latif al-Baghdadi
(Ibn al-Labbad). He examined 10,000 cadavers removed from the hills of al-Muqattam,
east of Cairo, during the construction of a road. He realized this fact after
observing thousands of examples. This was revealed in his wonderful book al-Ifada
wa l-i’tibar fi l-umur al-mushahada wa l-ahwal al-mu‘ayana fi ardi Misr, (review
and lessons from examinations and experiences in Egypt).
Ibn Rushd wrote of the teeth that there are 16 in each jaw—two central incisors,
two lateral incisors and two canines, and five molars and premolars on both
right and left sides. There are three or four roots in the maxilla but only two
in the mandible, the remaining teeth have only one root.
He also described the large aperture in the back part of the skull, the foramen
magnum, and its relation with the seven vertebra of the neck (cervical vertebrae),
which have apertures on the sides. The vertebrae of the chest region are twelve;
in the lumbar there are five, linked to the sacrum in which he counted three
bones (in fact there are five) attached to the bone of the coccyx which is also
composed of three attached vertebrae.
Ibn Rushd said that all vertebrae are articulate except the first two from the
neck, because the first vertebra is attached to two appendices ramified from the
skull.
He also said the bone of the sacrum is attached from the sides of the hips, in
each of which is the acetabulum (socket) which contains the ‘head’ of the thigh
bone (femur), often referred to as the ‘pomegranate’.
Ibn Rushd described in detail the bones of the front side starting from the
clavicles up to the pubic bone, passing by the ribs and the bones of the
shoulders. He also described the upper and lower limbs very precisely. What he
wrote is not different from what we know today except that, for the bones of the
arm, he uses ‘lower’ and ‘upper’ zanad (forearm) to mean the radius and the ulna.
He indicated the bones of the leg, nowadays known as the fibula and tibia, in
the same terms.
Veins and arteries
In the old days, the arteries were called the ‘beating veins’ (dhawarib ), and
jugular veins were the ‘non-beating’ veins (ghayr al-dhawarib ). Ibn Rushd made
a precise distinction between the two types of veins which remains accurate and
valid. He wrote:‘Arteries come out of the heart whereas the jugular veins come
back to it.’ He also described the difference precisely, the arteries are more
solid and have two similar layers: the fibres of the inner layer are crosswise
while the outer layer fibres are length-ways—even by modern standards a very
professional anatomical description.
Two arteries of different size come out of the heart, the smaller one goes to
the lungs and ramifies into them (pulmonary artery). The other (aorta) is larger,
divided into many sections and ramifies into the whole body, one section going
up to the head and upper limbs, another going alongside the vertebral column
with branches leading to the chest and abdomen; it ends in the lower body and
feeds the two lower limbs.
Ibn Rushd’s fascinating description is confirmed as correct and accurate.
However, he failed to observe the circulation of the blood accurately. This was
not properly described until nearly a hundred years later by Ibn al-Nafis (d.
1288) a Damascus-born physician who worked in hospitals in Cairo, and many
centuries before William Harvey (1578—1657).
The
nervous system
The nervous system is the most complicated organ in the human body and its
anatomy has only gradually become known over recent centuries. Nevertheless, Ibn
Rushd was able to describe the brain, its membranes and the cranial nerves. He
describes the smelling nerve perfectly, pointing out that it ends with a nipple
like that of the breast. He does not consider this nerve as the primary one,
giving that distinction to the optical nerve. The first pair of nerves issue
from the brain and form the sclera inside the cranium, then come out to the eyes
each from its side. This is a wonderfully precise description.
Ibn Rushd then describes the nerves that feed the muscles of the eye. According
to modern anatomy, these nerves are the third, fourth and sixth, but Ibn Rushd
considers them all as the second pair that ramifies in the muscles of the eyes.
He considers the third pair as related to the next (the fourth), and these feed
areas of the face, the ear, the palate and the nose—in fact, he was writing
about the fifth and seventh pair of nerves according to modern anatomy. As for
the fifth, Ibn Rushd says that a part of it leads to the ears and the muscles of
the cheeks, whereas this is identified as part of the seventh pair.
Ibn Rushd writes that the sixth nerve feeds the pharynx and the tongue and part
of it leads to the muscles near and around the shoulder and another part
deviates to the neck and a branch of that goes to the larynx. This is actually
the eleventh nerve (the accessory nerve) and there is some confusion in Ibn
Rushd’s account with the description of the tenth nerve (vagus; the wandering or
confused nerve). Although he attributes many characteristics of the vagus nerve
to the accessory one, Ibn Rushd is very accurate in the description of the
characteristics themselves. He observes that some of the branches of this nerve
lead to the chest and feed the heart, lungs, and esophagus; that it runs through
the diaphragm and makes the link with the cardiac and liver membranes, the
spleen and the rest of the intestines/bowels.
Ibn Rushd describes the seventh nerve as starting from the back of the brain and
ramified in the tongue: he is describing accurately the twelfth nerve (hypo-glossal).
He describes as accurately as modern anatomy does, the nerves that go along the
vertebrae. He mentions the eight pairs of cervical nerves, sixteen pairs of
dorsal nerves, and five pairs of lumbar nerves.
He misses the correct number of the sacral nerves, they seemed only three to him
because they are very closely attached—in fact they are five. Three nerves come
from the bone of the coccyx and a single nerve comes out on the sides from the
middle. This is absolutely accurate.
Ibn
Rushd wrote;
‘The brain has two nipple-shaped appendices that grow from its two advanced
abdomens (olfactory bulb). They reach the bone that resembles the cribrium (cribriform
plate), which is perforated with many holes [i.e. like a sieve], not smooth but
rough with its position in the cranium, where it reaches the end of the nose.’
It would be very hard to improve on the concision or accuracy of this account
even today.
About the membranes of the brain, he wrote, again with wonderful, inspiring
accuracy:
The brain has two membranes, one is hard and thick (dura mater), and the other
is thin (pia mater), they cover the brain very closely and in some locations are
completely joined. The thick one is adherent to the cranium. This membrane has
many perforations in two places, the first at the canal at the end of the nose (cribriform
plate), and the second at the bone of the palate. Under the brain on the thick
cover, there is the mysterious net composed of veins that go up to the head.’
The
structure of eye
Ibn Rushd’s ability and competence as an anatomist is most clearly demonstrated
in his description of the eye and its layers, which compares most favorably with
what is known today except some minor differences in terminology. Ibn Rushd had
even established the original development of the layers of the eye in the fetus,
and discovered that they appear to imitate the layers of the brain and its
membranes. Ibn Rushd combined accurate observation with brilliant exposition,
sight with insight, presenting the structures of the eye as well as any
twentieth-century expert could, and did so many centuries ahead of any physician
in Europe.
He wrote:
The eye is composed of seven layers and three liquid areas. The first, from the
side of the cranium, is a membranous layer that develops from the thick layer (sclera).
The next layer from outside develops from the thinner membrane of the brain; it
is called al-mashima (choroid). The next is a layer similar to the net (retina).
It grows from the same nerve that comes out of the brain. In the middle of this
layer, there is a soft and liquid area called al-rutuba al-zujajiyya (vitreous
humour). Inside it, there is another spherical body but with some minor flatness.
It is as clear as the ice and called al-rutuba al-jalidiyya , and we call it
nowadays al- ‘adasa (lens).’
Ibn Rushd continues this wonderful description, by mentioning al-rutuba al-ma’iyya
al-amamiyya (aqueous humour), he also called it al-rutuba al-baydhiyya because
its liquid is similar to the soft liquid egg-white:
‘On the outside of this liquid appears a soft body whose inner texture is velvet-like,
that follows the al-rutuba of baydhiyya (aqueous humour); smooth from the
outside its colour is different from the body of the other, it can be very black
or less dark or even blue.’ This is an extremely precise description of the iris
(quzahiyyatu al-‘ayn) and the ciliary body (al-jism al-hudhabi).
He adds:
‘Inside the ciliary body, next to the lens, a hole that widens and narrows
depending on the extent of darkness that it needs, the hole is called hadaqa (pupil)
and the membrane itself is called the inabiyya (grape- like) layer.
‘Next to this layer, a cover that has a hard and clear white and thin plate
which is called al-qarniyya (cornea). It takes the colour of the layer below it.
On the top of this rises a white body called al-multahim (conjunctiva).’
Ibn Rushd also wrote about the physiology of sight:
‘The sight is not a thing that comes out of the eye as Galinius used to think.
The eye receives the colours through the reflecting objects in which they are
held, in the same way as a mirror does. Once the colours are reflected in the
eye, the object is then conceived by the visioning power.
‘This could well be proved in natural science (physics). That is why any of
those parts of the eye is able to reflect the colours because of its very glossy
surface. So that body is the special tool to the lens and the advantage of the
qarniyya (cornea) is . . . [that] it is made clear and thin so that it does not
prevent the ice-like liquid (lens) from receiving the images.’
This is an accurate description of the eye and the physiology of sight that does
not differ much from what we know today.
From this brief dip into a chapter of al-Kulliyyat fi al-Tibb , we realize the
importance of the work of Ibn Rushd—jurist, philosopher, physician. He was an
expert in each of these fields and the most distinguished scholar in Spain and
North Africa. He neither experienced nor discovered any contradiction between
his religion and his science; rather, his quest for knowledge and excellence,
his wonderful curiosity, enlightened and improved his faith. His famous
observation— who practises autopsy, his faith in God increases —should silence
the false allegation that Muslims never practised anatomy and that they are
against applied sciences. What has been written by so many Muslims in all fields
of knowledge refutes this allegations. Medicine and the other applied sciences
are a necessary and essential contribution to the well-being of humankind.
Therefore, to work in them is fard kifaya , a collective obligation upon the
community of Muslims as a whole, an obligation which some members of the
community must undertake on behalf of the others who cannot.
Islam is the guide for those who seek true and sound knowledge in every subject.
All sciences, so long as they are directed to God and not to merely worldly ends
or personal glory, bring their students closer to God and make easier the way to
approach and please Him: Those who fear God, amongst his servants, are those who
have knowledge. And God is the Guide to the straight path.
Source: fountainmagazine.com

