Herophilus of Chalcedon and the practice of dissection in Hellenistic Alexandria

Here we present selected parts of the very interesting paper “Herophilus of Chalcedon and the practice of dissection in Hellenistic Alexandria“, February 2008 Vol. 98, No. 2 SAMJ, by Goran Štrkalj & David Chorn.

The dissection of human cadavers is a complex topic that can be comprehended only if a number of factors are taken into account, as illustrated by the example of Herophilus
of Chalcedon, who was the first dissector in the Western medical tradition. The social, cultural, political and intellectual climate of Hellenistic Alexandria in the third century BC provided Herophilus with opportunities to dissect – and possibly vivisect – human bodies. He was thus able to make an unprecedented number of anatomical discoveries and accompanying accurate descriptions. Subsequent changes in Alexandrian society and its intellectual climate saw the rapid demise of the practice of dissection – its resurgence occurring only some 15 centuries later.

(…) It was a long time before human dissection was introduced into Western medicine. Yet, for a brief period, two scientist-physicians in Hellenistic Alexandria during the third century BC, Herophilus and Erasistratus, performed such dissections. Only some 15 centuries later was the practice re-introduced in Western medicine.

(…) Following the death of Alexander the Great, his generals divided the vast empire between themselves. Alexander’s close friend Ptolemy acquired Egypt and made Alexandria its capital. The Ptolemaic dynasty ruled Egypt for almost three centuries, until Rome conquered the land. Ptolemy I and his successor, Ptolemy II Philadelphus, were determined to make Alexandria the artistic and scientific centre of the world. The two autocrats succeeded magnificently. The famous Alexandrian Museum and Library, together with substantial royal incentives, attracted learned scholars and students from across the ancient world. Among them were Archimedes, Euclid, Eratosthenes, Aristarchus, Conon and Ctesibius – as well as Herophilus and Erasistratus, two physicians who made an extraordinary contribution to anatomy and medicine.

(…) Many documents about Herophilus have been lost or destroyed. His own writings, in fragmented form, are preserved only in the works of later authors. Classical scholars and medical historians have reconstructed the general profile of his life and work, but many aspects are still cloaked in uncertainty. Herophilus was born between 330 and 320 BC in
the provincial town of Chalcedon, situated on the Asiatic side of the Bosphorus; he died between 260 and 250 BC. Like many of his contemporaries, he used the social climate of growing Hellenistic cosmopolitanism to forge a distinguished career in Alexandria, probably during the rule of Ptolemy I and Ptolemy II. He was educated under Praxagoras, a prominent physician of the Hippocratic School, in all likelihood at the
school’s centre on the island of Cos. Although various sources attribute authorship of 11 books to him, it is generally believed that in fact he wrote between 6 and 8. These covered various medical topics, were widely distributed, and remained current for a considerable length of time. Herophilus was said to have been a brilliant teacher who attracted numerous students from around the known world. The Herophilean School continued to flourish after his death, although his work was later ‘…plunged into obscurity in part by the popularity of rival schools and in part by the durability and canonicity of Galen’s subsequent system …’ (according to Von Staden H. – Herophilus: The Art of Medicine in Alexandria. Cambridge: Cambridge University
Press, 1989.) , and was resurrected much later by the
Renaissance physicians.

(…) According to later commentators, Herophilus performed no less than 600 dissections, privately and for the public. Sources from antiquity, such as the renowned Roman
medical encyclopaedist Celsus, claim that Herophilus also practised vivisection. The Egyptian ruler apparently sent convicted criminals to Herophilus, who was free to perform any experiment on them. The authenticity of this claim is often questioned, though the knowledge presented by Herophilus might have been acquired through dissection of human cadavers and vivisection only of animals. Yet in the light of the atmosphere prevailing in Alexandria and Herophilus’s propensity for entertaining radically new approaches which were acceptable there but an anathema in his city of origin, it may be deduced that he practised vivisection. Herophilus’s younger contemporary, Erasistratus, might have been even more likely to have conducted human vivisection as he seemed to be interested more in physiology than anatomy.

Herophilus’s research into the structures of the human body, as presented in the book On Anatomy, were unprecedented. Although he was not as well known as other physicians in antiquity, such as Hippocrates and Galen, Herophilus has been hailed as the father of anatomy and of other disciplines such as neuroscience. Herophilus ‘ … made
basic discoveries in nearly every system of the body … ’ (according to Potter P. – Herophilus of Chalcedon: an assessment of his place in the history of anatomy. Bull
Hist Med 1976; 50: 45-60). Although some of these assessments may seem exaggerated,
his contribution to anatomy and medicine in general was profound, while his influence on subsequent generations of physicians was substantial.

(…) because On Anatomy was lost to posterity, secondary sources reveal that it is likely that Herophilus made more contributions than those of which we are aware. Perhaps
the most spectacular of his insights relate to the nervous system. Like the earlier Greek physician Alcmaeon of Croton – but unlike Aristotle and the majority of experts before him – Herophilus believed that the brain, and not the heart, was the ‘seat of the soul’. He was the first to distinguish between motor and sensory nerves and also between spinal and cranial nerves. He described at least seven cranial nerves and named six pairs: the optic, oculomotor, trigeminal, facial, auditory and hypoglossal nerves. He also described the cerebrum, cerebellum and meninges; distinguished between the four ventricles; and described and named the calamus scriptorium of the fourth ventricle, and the choroid plexus (termed thus because of its resemblance to the membranes wrapped around a fetus). He also studied the internal surface of the skull and described the confluence of sinuses. The concavity on the internal surface of the occipital bone, in which lodges the
confluence of sinuses, was eponymously termed the torcular herophili, which is sometimes erroneously used to denote the confluence of sinuses itself. Herophilus also named the styloid (‘pen-shaped’) process of the skull and differentiated and described the various layers of the eye. He provided detailed descriptions of the salivary glands, the liver (including the hepatic portal system, the significance of which he recognised)
and the pancreas, as well as the first part of the small intestine which he named the duodenum (‘twelve fingerbreadths’). He recognised that the testicles produce spermatozoa, and identified the various parts of the spermatic duct. He described the prostate and the womb, showing that the latter was attached by the broad ligament and thus not mobile about the body as had been previously thought. A description of the
lacteals, lymphatic fluid, the ovaries and at least part of the uterine tubes, flowed too from his keen observations. Pursuing the fields of interest of his teacher Praxagoras, he accurately distinguished, both anatomically and functionally, between veins, arteries and nerves.

For Herophilus, a knowledge of anatomy contributed towards medical practice and particularly surgery. Some medical insights, such as the recognition that tremor was the
result of nerve failure, probably resulted from his anatomical research. His book on midwifery was based largely on his dissections of the female genital organs. Herophilus, like Praxagoras, was interested in the diagnostic value of the pulse and constructed a special clepsydra to measure this.

(…) As suddenly as the practice of dissection appeared within medical and scientific milieu, it as rapidly disappeared following the deaths of its two chief protagonists, Herophilus and Erasistratus.

Research-Selection: Anastasius Philoponus