Herophilus

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Herophilus

(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 ??ò? ??? ?????? ?????, 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 ?????????? (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 (???????? ???????; 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” (?????????) 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 (?????); the Latin term torcular Herophili is still in use. His description of the rete mirabile, or retiform plexus (??????????? ??????), 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 (????????) disappeared. To describe this final part of the artery he used the term ??????—meaning, presumably, that it resembled the sinews. Galen tells us that it was by the operation of these ????? 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 ????????, as Erasistratus subsequently did, but ??????????? (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” (?????). In this instance he did not use the technical term ????? but retained the more familiar terminology. Galen adds that Herophilus was of the opinion that these ????? contained ????????ò? ?????? 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” (? ?????????????? ???????), 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 (??????????) the heterorhythmic (????????????) and the ecrhythmic (????????) 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” (???? ??????????) 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 (?????????) 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.

NOTES

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.

BIBLIOGRAPHY

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).