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(b. Chalcedon, Bithynia, last third of the fourth century b.c.)

anatomy, physiology.

Only scanty information concerning Herophilus’ life has been preserved; the place and date of his death are unknown. We learn from Galen that he was a native of Chalcedon, which was originally a Megarian colony on the Asiatic side of the Bosphorus (III 21K.; XIV, 683K.), that he studied under Praxagoras of Cos (VII, 585K.; X, 28K.), and that later he taught and practiced medicine at Alexandria, first under Ptolemy Soter and subsequently under Ptolemy Philadelphua. In Alexandria he lived in an environment in which the dissection of the human body did not meet with general disapproval.1 Such an atmosphere, possibly unique in Greek cities at that time, clearly proved beneficial to the development of scientific anatomy, and Herophilus’ researches significantly advanced this study. His interest in comparative anatomy is also recorded.2

Herophilus acquired great prestige, both as a practitioner and as a teacher of medicine, and students flocked to Alexandria to sit at his feet. He is described by Galen as a member of the “dogmatic” school of medicine, that is, he was a follower of the “logical” or “dialectical” method, as opposed to mere empiricism.3 Although Galen at times criticizes Herophilus for being obscure, his usual assessment is that he was a great physician commendable for the soundness of his views and especially for his combination of careful observation and reasoning.

The medical writings of Herophilus were not extensive. None of his works has been preserved, but it appears that he wrote at least eleven treatises, of which three were devoted to anatomy, one to ophthalmology, one to midwifery, two each to the study of the pulse and to therapeutics, one to dietetics, and one entitled Πρòς τάς κόινάς δόξας, which was evidently a polemic against commonly held medical views which he believed to be mistaken. It is recorded that he did not hesitate to question even the views of Hippocrates himself. Yet he did not depart altogether from Coan teachings but, following his master Praxagoras, based his medical theory upon the doctrine of the four humors (V, 685K.; see Celsus, On Medicine, introduction, ch. 15).

It was in anatomy that Herophilus made his greatest contribution to medical science, conducting important anatomical investigations of the brain, eye, nervous and vascular systems, and the genital organs. He also wrote on obstetrics and gynecology and held an elaborate quantitative theory of the pulse. Several medical terms, some still in current use, were coined by him.

The result of Herophilus’ anatomical researches into the brain was that the Peripatetic confusion of the functions of the brain and the heart was corrected and that there was a reversal to the minority view, originally propounded by Alcmaeon, that the brain is the central organ of sensation and the seat of the intellect. As a result of his dissections, Herophilus was able not only to distinguish the cerebrum from the cerebellum but also to demonstrate the origin and course of the nerves from the brain and spinal cord (III, 813K.; VIII, 212K.). We are further informed that he specified the “fourth ventricle” or the. “cavity” of the cerebellum as the seat of the ήγεμονικόν (Rufus, De corp. part. anat. 74 [185], Daremberg and Ruelle, eds.; Aët. 4, 5, 4; Galen, De usu. part IX. I, III, 667K.). This cavity in the middle of the floor of the fourth ventricle he compared to the cavity in the pens used in Alexandria (άναγλυϕή καλάμου; II, 731K.), and the Latin term calamus scriptorhis or calamus Herphill remains in current medical use. The three membranes of the brain were also recognized by Herophilus and designated as “chorioid” (χοριοειδή) because they resembled the chorionic envelope surrounding the fetus (II, 719K.). He observed and likened the meeting point of the sinuses of the dura mater to a wine press (ληνός); the Latin term torcular Herophili is still in use. His description of the rete mirabile, or retiform plexus (δικτυοειδές πλέγμα), as he called it (V, 155K.), at the base of the brain affords further evidence of his dissection of animals, since it does not exist in man.

Herophilus’ discovery, by dissection, of the nerves and his demonstration that they originate in the brain enabled him to answer the question raised by Praxagoras: to what kind of organ the extremities of the body owe their movement. Praxagoras and Diocles had successfully distinguished between arteries and veins,4 both believing that pneuma moved through the former and blood through the latter. Having thereby provided specific channels through which voluntary motion could be imparted to the body, Praxagoras then conjectured that certain arteries became progressively thinner, with the result that ultimately their “walls” fell together and their hollowness (κοιλότης) disappeared. To describe this final part of the artery he used the term νεύρον—meaning, presumably, that it resembled the sinews. Galen tells us that it was by the operation of these νεύρα that Praxagoras accounted for the movement of the fingers and other parts of the hands. Thus, although Praxagoras did not himself actually isolate and identify the nerves as such, he nevertheless played an important role in their discovery a generation later by Herophilus.

It was Herophilus, then, who transferred to the nerves the function which Praxagoras had assigned to the arteries. Rufus preserves for us the additional information that he also distinguished between the sensory and motor nerves, calling the latter not κινητικά, as Erasistratus subsequently did, but προαιρητικά (De Corp. part. anat., 71–74 [184, 13 ff.], Daremberg and Ruelle, eds.). Herophilus also succeeded in tracing the sensory nerves leading from the brain to the eyes (III, 813K.) and called them “paths” (πόροι). In this instance he did not use the technical term νεύρα but retained the more familiar terminology. Galen adds that Herophilus was of the opinion that these πόροι contained αΐσθητικòν πνεύμα and elsewhere he gives the reason why Herophilus considered the optic nerve to be a particularly suitable carrier of pneuma: he had discovered by dissection that these “strings” were hollow (VII, 89K.).

Herophilus was deeply interested in the liver and, as has been seen above, he applied the methods of comparative anatomy to its study. His knowledge of its conformation was extensive and, for the most part, accurate. He observed that it differs in size and conformation in different individuals of the same species and that occasionally it occurs on the left instead of the right side (II, 570K.). The name “duodenum” (ή δωδεκαδάκτυλος έκϕυσις), which he derived from its size, was applied by him to the first part of the small intestine (II, 708K.; VIII, 396K.). He was also the first to isolate the lacteals or “chyle vessels,” as they are now called, thereby anticipating Gasparo Aselli, who explained their function in the seventeenth century.

Having drawn the distinction between veins and arteries, Praxagoras gave the pulse a role in diagnosis and therapeutics. This pioneer work was subsequently developed by Herophilus,5 who wrote treatises on this subject, and it is recorded—albeit in a late testimony6—that he was the first to count the pulse by means of a clepsydra. He seems to have employed four main indications of the pulse—size, strength, rate, and rhythm (VIII, 592K.)—and to have distinguished certain cardiac rhythms as characteristic of different periods of life (IX, 463K.). In addition to normal pulses which follow natural rhythms he distinguished three divergent pulses: the pararhythmic (παραρύθμοι) the heterorhythmic (έτερόρρυθμοι) and the ecrhythmic (έκρύθμοι) of these the first indicates only a slight divergence from normality, the second a greater, and the third the greatest (IX, 471K.). It seems likely that Herophilus was indebted to contemporary musical theory for this terminology.

Herophilus maintained that pulsation was entirely involuntary and was caused by the contraction and dilatation of the arteries in accordance with the impulse received from the heart (VIII, 702K.). He believed, erroneously, that dilatation represented the normal condition of the arteries. Actually, contraction is the return of the artery walls to their normal condition and dilatation is due to the pressure of the blood from the heart. But however that may be, he clearly recognized the connection between the heart and pulse beats. Herophilus also noticed the existence of a pulmonary systole and diastole and, upon the basis of their alternating rhythm, sought to explain the respiratory process. He believed that respiration followed a four-stage cycle comprising the intake of fresh air, the distribution of that fresh air to the body, the intake of used air from the body, and the expulsion of this used air (XIX, 318K.). His knowledge of the pulmonary blood system does not appear to have been extensive. Rufus tells us that he called the pulmonary artery the “arterial vein” (ϕλέψ άρτηριώδης) and asserted that in the lungs the veins resemble the arteries and vice versa (p. 162, Daremberg and Ruelle, eds.; see also Galen, III, 445K.). Herophilus based this assertion upon comparative thickness and estimated that the walls of an artery were six times as thick as those of a vein (see also II, 624K.)

There is no evidence that Herophilus made any significant contribution to the knowledge of the male organs of generation, but does seem to have made intensive studies in gynecology. In his treatise on midwifery (μαιωτικόν) he accurately describes the ovaries, the uterus, and the cervix, and he had observed the Fallopian tubes. Soranus tells us that Herophilus was interested in the relationship between menstruation and general health (p. 192R.; I. 29, 1 ff., Heiberg, ed.). He also preserves Herophilus’ summary of the causes of difficult labor (p. 349R.; IV. 1, 4 II., Heiberg, ed.), foremost among which are held to be frequency of parturition, displacement of the embryo, and insufficient dilatation of the cervix. We also learn from Soranus that Herophilus described the causes of uterus prolapsus and rightly held that only the cervix, and not the entire uterus, can protrude (p. 372R.; IV.36, 1–2, Heiberg, ed.).

Although Herophilus’ chief interests lay in anatomy, he also displayed a keen practical interest in other branches of medical science. He wrote a treatise on dietetics and recommended gymnastics as a means of preserving health. Although he stressed the importance of diet, regimen, and exercise, our evidence suggests that he placed too much reliance upon drugs. Celsus even goes so far as to say he would never treat any disease without medicine (De Medicina, V , ch. 1; see also Galen, XI, 795K.; Pliny, Naturalis historia, XXVI, 11).

The school founded by Herophilus had centers in both Alexandria and Laodicea. His followers neglected anatomy and to a large extent dissipated their energies in sophistry and unrewarding controversy with the rival school of the Erasistrateans. Consequently very few of them achieved preeminence in medicine.7 Herophilus’ own reputation, however, stands apart from that of his school. His true importance lies in the fact that he, together with his younger contemporary Erasistratus, laid the foundations for the scientific study of anatomy and physiology. Their careful dissections provided both a basis and a stimulus for the anatomical investigations undertaken by Galen over four centuries later.


1. For the tradition that both Herophilus and Erasistratus vivisected humans, see James Lonenge, “Erasistratus,” in Dictionary of Scientific Biography, IV, 382–386.

2. Galen tells us (II, 570K.) that he noted differences between the livers of men and hares.

3. For a description of these two opposed schools of medical thought, see Celsus, On Medicine, intro., chs. 8–35.

4. F. Solmsen, “Greek Philosophy and the Discovery of the Nerves,” p. 179.

5. Some scholars (for example, Gossen, col. 1106 followed by Dobson, p. 21) have maintained that Herophilus rejected Praxagoras’ belief that the pneuma moves through the arteries and maintained that these vessels were full of blood. But their standpoint is based on a misinterpretation of Galen IV, 731K.

6. Marcellinus, De pulsibus, xi, H. Schöme, ed. (Basel, 1907).

7. Notable exceptions among Herophilus’ pupils were Demetrius of Apamea and Philinus of Cos.


References to Galen are cited according to Claudii Galeni opera omnia, C. G. Kühn, ed., 20 vols. (Leipzig, 1821–1833); to Rufus. according to the ed. of C. Daremberg and E. Ruelle. Oeuvres de Rufus d’Ephése (Paris, 1879; repr. Amsterdam, 1963); and to Soranus, according to the ed. of V, Rose, Soranus (Leipzig, 1882), and to that of J. Ilberg, Sorani Gynaeciorum libri IV,... (Berlin, 1927).

See also C. Allbutt, Greek Medicine in Rome (London, 1921); J. F. Dobson, “Herophilus,” in Proceedings of the Royal Society of Medicine, 18 , pts. 1–2 (1925), 19–32; H. Gossen, “Herophilus,” in Pauly-Wissowa, Real-Encyclopädie der klassischen Altertumswissenschaft, VIII (Stuttgart, 1912), 1104–1110; E. F. Horine, “An Epitome of Ancient Pulse Lore,” in Bulletin of the History of Medicine, 10 (1941), 209–249; W. H. S. Jones, The Medical Writings of Anonymus Londinensis (Cambridge, 1947); F. Kudlien, “Herophilus und der Beginn der Medizinischen Skepsis,” in Gesnerus, 21 (1964), 1–13, and in H. Flashar, ed., Antike Medizin (Darmstadt, 1971), pp. 280–295; K. F. H. Marx, Herophilus, ein Beitrag zur Geschichte der Medizin (Karlsruhe-Baden, 1838); and De Herophlil celeberrimi medici vita scriptis atque in medicina mentis (Göttingen, 1842); F. Solmsen, “Greek Philosophy and the Discovery of the Nerves,” in Museum Helveticum, 18 (1961), 150 ff.; A. Souques, “Que doivent á Hérophile et á Erasistrate l’anatomie et la physiologie du systeme nerveux?,” in Bulletin de la Société d’Histoire de la Medecine, 28 (1934), 357–365; F. Steckerl. The Fragments of Praxagoras of Cos and His School (Leiden, 1958); and G. Verbeke, L’évohttion de la doctrine du pneuma (Paris–Louvain, 1945).

For a more comprehensive bibliography, see James Longrigg, “Erasistratus,” in Dictionary of Scientific Biography, IV, 382–386.

James Longrigg

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Herophilus (335 B.C.–280 B.C.), considered the first anatomist in history, has been called the father of anatomy, given his role in the growth of anatomical science. He was the first doctor to base his conclusions on dissection of the human body, predating Leonardo da Vinci and Vesalius, both known for their explorations into dissecting bodies, by 1,800 years. He was extremely influential during his own time and his works were used for centuries.

Although all of his works were lost because the Library of Alexandria, which kept them, was destroyed in 272 A.D., later scholars quoted him extensively. Herophilus was advanced in his scientific methods. Adrian Willis in The Lancet quoted Herophilus as having said, "Let the phenomena be described first even if they are not primary."

Herophilus was born in 335 B.C. in Chalcedon, Asia Minor (now Turkey). Little is known about his personal life or even about the date and place of his death, which along with all his writings, have been lost. From secondary sources, such as the celebrated physician Galen, the Platonist and polemical writer Celsus, and the well–known theologian Tertullian in the 2nd century A.D., it is known that Herophilus wrote about a myriad of topics, including therapeutics, aphorisms, pulse lore, anatomy, gynecology, and ophthalmology.

Started Practice of Dissection

Herophilus first studied medicine under Praxagoras of Cos., before continuing his education in Alexandria. At the time, Alexandria was the center of learning and scholarship, and learned men from througthout the known world visited its famous library. Herophilus found his niche in Alexandria and stayed there the rest of his life. He started out there as a student before teaching and practicing medicine. In Alexandria, he was allowed to practice dissection, which was banned elsewhere and seen as an unnatural desecration of the body. In Alexandria, though, dissections became a fascination, so much that Herophilus performed them publicly when he became comfortable enough to explain what he was doing. His work drew widespread praise.

He took on an apprentice, Erasistratus. With Erasistratus, Herophilus is believed to have founded an advanced medical school in Alexandria which drew people from throughout the ancient world. Herophilus' fame made the school a success. Some of his methods, however, were considered controversial because he is thought to have sometimes done vivisections on live criminals, to see how the organs worked in a live body. There were no anesthetics at the time. Adrian Wills in Lancet magazine wrote about this: "Celsus and Tertullian (in On the soul) accused him of human vivisection ('Herophilus that doctor, or rather, butcher . . . death in his hands was not simply death, butled to error from the very process of cutting up'), but such accusations remain speculative."

When Herophilus was alive, conventional medicine revolved around the four humors: yellowbile, black bile, blood, and phlegm. To Herophilus, an imbalance of these four fluids triggered all diseases and ailments. An excess of yellow bile led to violence, vengeance, short–temperedness, and ambition. An excess of black bile led to introspection, sentimentality, and gluttony. An excess of phlegm made people sluggish, pallid, and cowardly. And an excess of blood made people more amorous, happy, generous, optimistic, and irresponsible. There were good and bad about each of the four humors, and it was only when they were in balance that a person could be happy and healthy. The veins visible through the skin were considered to be filled with air or water as well as blood. The brain was even thought as a sort of cooling chamber for emotions. Herophilus first suggested that the brain might be the seat of the intellect, and he imparted special importance on all of its ventricles. He also deduced that the veins carried only blood. He did however, have an idea about something called pneuma, which he thought was necessary to the health of the brain and the body and which flowed through the body via the arteries along with blood. According to Herophilus, diseases occurred when one of the four humors blocked the pneuma from reaching the brain.

Studied the Brain and Nerve System

Herophilus' dissections provided unprecedented knowledge of how the body and its organs worked. He was the first to suggest that intelligence resided in the brain, not the heart. He was also the first man known to differentiate between the cerebrum (larger portion) and the cerebellum (smaller portion) of the brain. He also catalogued and described many of the nerves located in the cranium, including the optic nerve for sight and the oculomotor nerve for eye movement, as well as facial, auditory, and hypoglossal (tongue) nerves. His extensive research into the nervous system differentiated between blood vessels and nerves. He also discovered the differences between the motor nerves, (those used for motion) and the sensory nerves (those used for sensation). This was especially remarkable because there were no microscopes at the time. After his discovery of the optic and oculomotor nerves he studied the eye in great detail, following the optic nerve and describing the retina.

He has also been credited with describing the calamus scriptorius, the part of the brain in which Herophilus thought the soul resided. He discovered and named the torcular herophili, which he found by investigating the brain's cavities and following the sinuses of the dura mater (the tough, stringy membranes covering the brain and the spinal cord that lines the inner surface of the skull) to their meeting point at the sinuses. He thought the sinuses seemed like a winepress, so he named the junction torcular Herophili, as torcular is the Latin word for winepress. These terms are still in use today.

Wrote Treatise on Gynecology

Herophilus thoroughly described the liver and the pancreas. He named the duo denum, the beginning of the small intestine that connects the stomach with the large intestine. He also looked at the alimentary canal, the digestive system tube that extends from the mouth all the way through the body, and which includes the pharynx, the esophagus, the stomach, and the intestines. He drew up schematics of the salivary organs. And during his research of the genital organs he drew up pictures of the ovaries, the uterus, and the Fallopian tubes—although they were not called that at the time—and was able to make a remarkably accurate treatise about the female body for midwives and other doctors.

The anatomist also researched extensively the differences between the arteries and veins, noting their functions and movements. He noticed that the arteries pulsed and he worked out standards for measuring this pulse and using it in diagnosis. He thought this arterial pulsation was reflex, due to the dilation and contraction of the arteries that occurred from the impulses sent from the heart. Herophilus corrected many of the more primitive notions prevalent at the time.

Proponent of Exercise and Healthy Eating

Herophilus was also one of the first doctors who advocated eating a good diet and exercising frequently to maintain health, two things that are still considered the most important proponents of healthy living. The World of Quotes recorded Herophilus as having said, "When health is absent, wisdom cannot reveal itself, art cannot manifest, strength cannot fight, wealth becomes useless, and intelligence cannot be applied." He was also a promoter of bleeding (the letting of blood to release excess pressures in the body) as well as drug therapy. He also invented the clepsydra, a portable water clock that measured time by marking the controlled flow of water through a small opening.

Herophilus died around 280 B.C., and his medical school dissolved soon after. And some time after that, the Library at Alexandria where all of Herophilus' works resided, was burned to the ground and all the books the Alexandrians had collected were destroyed with it. But the results of Herophilus' research passed through to the anatomists of the thirteenth century. Soon after Herophilus' death, the practice of dissection also ended, not considered a valid study again until many centuries later. In fact, when Leonardo da Vinci used the practice during the Renaissance to improve his ability to sculpt and paint realistic representations of the human body, it was still considered wrong. Gone were the days of Herophilus' dissection shows, but his scientific method and his learning have survived.


World of Biology, 2 volumes, Gale Group, 1999.

The Columbia Encyclopedia, Edition 6, Columbia University Press, 2000.

Merriam–Webster's Biographical Dictionary, Merriam–Webster, 1995.


Lancet, November 13, 1999.

Times (London, England), September 30, 2002.


"History of Ancient Greek Medicine," Archaeonia: A Journey through AncientGreece, (January 3, 2004).

"Herophilus," Flinders University, (January 3, 2004).

"Herophilus," Online Free Encyclopedia News, (January 3, 2004).

"Herophilus," World of Quotes, (January 3, 2004).

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Herophilus (hĬrŏf´ələs), fl. 300 BC, Greek anatomist, called by some the father of scientific anatomy. A contemporary of Erasistratus at Alexandria, he made public dissections, comparing human and animal morphology. He studied the structure of the brain (which he regarded as the site of intelligence) and the spinal cord and distinguished between motor and sensory nerves. He also investigated the eye, the alimentary canal (he is credited with naming the duodenum), the reproductive organs, and the arteries and veins.

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