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Thorax: first published as 10.1136/thx.33.2.153 on 1 April 1978. Downloaded from

Thorax, 1978, 33, 153-166

The thorax in history 2. Hellenistic and human

R.K. FRENCH

From the Wellcome Unit for the History of , of Cambridge

The first anatomical revolution occurred in Alex- the dead body was essential to the ancient practice andria in the third century before Christ. To that of embalming, an Egyptian technique well known period we can trace the continuous historical line to the Greeks. The Greek philosophers, and of our own ideas on the structure and function of , emphasised the distinction between soul the body, important among which are those on the and body:' it was the immaterial soul that sur- thorax. For the first time, the was vived the death of the corporeal body, and the systematically explored in an attempt to under- soul, sharing no characteristics with the body, stand its structure, and, with some notable errors could not be affected by the postmortem mutila- from , the only source for 'human' tion of the body; there was no quasi-material after- anatomy in the preceding period, these anatomical life in human form, as so many cultures believed. ideas are recognisably similar to those of to-day. In a word, the old religious taboos no longer The physiological ideas of the Alexandrians, on applied. the other hand, are strikingly different from ours, Of fundamental importance in the development and their subsequent transformation will be exam- of human dissection in was the exist- http://thorax.bmj.com/ ined in later articles. ence of a medical school (or schools). Even in the absence of specific cultural taboos, the dissection Human dissection of the body of a person recently dead naturally excites a feeling of revulsion; only in a medical The most important single reason behind this first school, where anatomy is considered a basic medi- anatomical revolution was the introduction of cal and becomes an established discipline, systematic dissection of the human body. It was is there sufficient mutual support within a group suggested at the beginning of the first article in to preserve an unpleasant practice, a sort of pro- on September 27, 2021 by guest. Protected copyright. this series (Thorax, 33, 10-18, 1978) that human fessional rejection of the normal taboos. Human dissection has been historically very rare and that dissection was a teaching device as well as a re- there were normally a number of taboos operating search tool. against it. We must briefly consider then why it Also associated with the development of medical was that the human body could be dissected in schools were medical and anatomical texts. Galen2 Alexandria. tells us that the ancient method of teaching Alexandria was the city of anatomy-he was thinking of the Hippocratic and shared fully in the cultural and commercial period-was oral, when the father (or master) exchanges of political empire. A cosmopolitan taught his sons (or apprentices) within the family population, the mixture of Hellenistic and group over a period long enough for the assimila- Egyptian culture, and the patronage of the arts tion of the great detail. Only when this system and by the Ptolemies all contributed to a began to break down and adult men were admitted cultural ferment. The changes that made Alex- into the circle to learn anatomy in a shorter period andria the centre of Hellenistic culture after the was it necessary to write down the anatomy. death of Alexander meant that no single system of Perhaps this increasing formalisation of teaching or belief held a dominant position, was becoming evident by Aristotle's time, for the nor were its taboos universally accepted. first textbook of anatomy is said to have been Apart from such general considerations, there written by Diocles of Carystos, a contemporary of are a number of particular reasons why human Aristotle.3 Many of the anatomical texts up to dissection should have flourished. The opening of the time of (second century AD) were 153 Thorax: first published as 10.1136/thx.33.2.153 on 1 April 1978. Downloaded from

154 R. K. French school textbooks, or at least the texts of pro- acquiring anatomical knowledge-dissection-was fessional anatomy teachers. A written tradition, disgusting and unnatural. It was, moreover, mis- of course, is open to detailed and precise modifica- leading, since the organs of the body changed in tion, and Galen's own treatment of the work of death. It was undoubtedly to see the organs of the his predecessors is the beginning of textual and living body that the Rationalists employed vivi- anatomical scholarship, upon which later develop- section, a technique that the Empiricists con- ments depended. sidered inadmissible on the grounds of cruelty. A natural result of teaching within a school, as The Empiricists argued that the only form of ana- opposed to a father-son line of oral instruction, is, tomical knowledge necessary and proper to a physi- in addition to texts, a comparatively large number cian was that gleaned 'accidentally' from . of students with similar ideas. Future teachers, chosen from the students, would perpetuate these The influence of Aristotle ideas alongside the texts, so that the physical school becomes also a 'school of thought'. The question of the extent of Aristotle's influence Aristotle's Lyceum became a school of peripatetic on the Alexandrian experimenters is not agreed philosophy, opposed to others, like the atomist or among historians, but a brief discussion of the stoic. In the same way the medical schools de- topic will serve to highlight some important issues veloped traditional ideas: from theoretical and to introduce the achievements of the positions already available in the Hippocratic Alexandrians themselves. corpus, and in parallel with the medical schools Wellman and Jaegar argue that there was a that had already been in existence for two or three considerable line of influence from Aristotle centuries on the periphery of the Greek world, through Diocles,6 whom we have already met as there developed in Alexandria, during the period the author of the first anatomical textbook. If it is we are discussing, a number of medical 'sects' indeed true that Diocles thought of himself as a with profoundly different views on the usefulness follower of Aristotle, then his book on human of anatomy in medicine. The Dogmatists or anatomy might well have been designed to fill the Rationalists, inclined to , held most obvious gap in Aristotle's biological works. that it was possible in principle to understand the The fragments of Diocles' work that survive show http://thorax.bmj.com/ processes going on inside the body, and that there- that his anatomy was in fact derived from , fore the was justified in intervening in and it may be that, like Aristotle, he was unable to these processes to put right what had gone wrong dissect the human body and relied on a in illness. As function was closely related to struc- methodology that consciously extrapolated from ture, it followed that anatomy was a fundamental to human. All this, how- medical science. It is possible that this attitude ever, is supposition, and all we can say with confi- was reinforced by the observational, empirical, dence of Diocles is that his treatment in general and like Aristotle he and inductive methodology that Aristotle had is like that of Aristotle, on September 27, 2021 by guest. Protected copyright. announced and put into practice in his zoological placed the soul in the . On the other hand, works. some important physiological and anatomical It appears that the Rationalists of Alexandria ideas of the Alexandrians and some of their wider took this methodology one step further and beliefs are quite opposed to Aristotle, and practised not only dissection, to discover human Steckerl7 argues that his influence has been over- anatomy, but ,4 to discover the function emphasised. of the human body. In other words, they intro- Whether or not a direct transmission of duced experiment into the descriptive and observa- Aristotelian ideas can be identified, there is no tional method. Both dissection and vivisection doubt of the background importance of his were opposed by the Empiricists,5 who from philosophy. His argument that even terrestrial Hippocratic times had believed that the processes objects were worthy of the attention of a philo- of the body were ultimately incapable of explana- sopher was new to Greek science and a turning tion. The business of the physician was not, there- point within it.8 His programme of analysing the fore, to intervene but to observe; empirical whole natural world encouraged his successor, based on case , to work on plants, at the descrip- medicine emphasised prognosis led history and treatment based on regimen. The non- tion of which Aristotle had stopped short, and empirical physician, rejecting the his student, Clearchus of Soloi, to write a book on investigative bones and muscles, need of a knowledge of function, had no need of the anatomy of the human of structure, and he held not only that another gap in Aristotle's world picture. Clearchus knowledge first of the Alexandrian anatomy was unnecessary but that the means of was contemporary with the Thorax: first published as 10.1136/thx.33.2.153 on 1 April 1978. Downloaded from

The thorax in history 2. Hellenistic experiment and human dissection 155 anatomists and may have had access to human Alexandrians, made some dramatic and sophisti- material in Alexandria. Certainly Aristotle's em- cated sectioning the controlling phasis on the primacy of the senses in scientific the motions of respiration. Its importance for our investigation must have greatly encouraged the story is that the discovery of the central nervous development of human dissection in Alexandria.9 system at once threw into relief the traditional (We have already seen how Aristotle's philosophy debate about the most important of the displaced some old taboos.) Although Aristotle's body, the seat of the soul. method was in a sense empirical (as opposed to the Quite apart from the other influences of the deductive system of Plato) it was part of a highly Aristotelian philosophy that we have discussed, a rational attempt to understand the natural world. major influence was that Aristotle had said that It was rational in seeking to establish the causes the heart was the seat of the soul, the organising of things, and this was an attitude that appealed centre of the body. This position became increas- to the medical Rationalists of Alexandria. ingly difficult to maintain as the function of the This rationality of Aristotle and others lay in and nerves became clear. The nerves were uncovering the plan according to which nature had now distinguished from the other fibres of the been put together. Perhaps the first appearance of body; neura became a technical term meaning this rationality appears in the 'Hippocratic' work 'nerves' only, and it was recognised that only on the heart, Peri Kardies, the author of which neura had a sensitive and motor function. Yet so admires the skill with which the valves of the great was the influence of Aristotle that some heart have been constructed. Peri Kardies, better anatomists attempted to reconcile Aristotle's non- known under the title De Corde, is prob- nervous neura of the heart (regarded as the ably closer in time to Aristotle than to Hippo- organising centre) with the new anatomy and crates. By then it was accepted that the reason . Thus , who is placed by employed by Nature the craftsman, or the some historians in a direct line of influence from demiurge who, Plato said, created the body, was Aristotle and Diocles to the great Alexandrians, of the same kind as human reason, and man Herophilus and , claimed that the could, therefore, in principle understand how the , arising from the heart, finally became too natural world had been constructed. Anatomy now narrow to admit and became nerves. Since http://thorax.bmj.com/ had a new function: it was no longer simply a the work of Herophilus and Erasistratus exists only medical affair, useful in understanding the struc- in fragments" we cannot tell what directed their ture and function of the body, and useful in attention to the central ; most ; it was also a philosophical exercise in probably it was a continuation of older Greek learning how the body was constructed. work on the sense organs, and particularly the eye. Some of this interest may have been originally The results of human dissection generated as a result of philosophical problems of

perception. We have already noticed a previously on September 27, 2021 by guest. Protected copyright. The major achievement of the Alexandrians was unrecognised addition to our knowledge of Hero- the discovery of the central nervous system. Of philus's work on the optic nerves in a passage of course, as we have already seen, the brain, spinal Chalcidius,'2 and it is possible that he generalised, cord, and nerves had already been recognised from this and other examples of the connections anatomically, and some dim awareness of the between the sense organs and the brain, to the motor and sensory powers of the brain had been statement that the brain is responsible for all the cause of a traditional placing of at least part of sense and motion. the soul in the head. But the Alexandrians knew Whatever led Herophilus to these ideas, it was that the central nervous system was the organising clear enough that the heart, the traditional seat of centre of the body; they distinguished between the soul and the prime organ of the thorax, could motor and sensory nerves, and we have every never be the same again. Two other discoveries reason to suppose that they experimentally just before or at the beginning of the Alexandrian sectioned nerves in the living animal-perhaps, period further transformed ideas about it and the indeed, in living man-and learned from the pattern of blood flow through it. The first of these result the function and distribution of the nerves. was the final clarification of the distinction of Discoveries thus made by experimental vivisection arteries and . While earlier authors had some were taught by the descriptive anatomy of dis- glimmering of this, a striking difference between section.10 The central nervous system is not of the two sets of structures was made by Praxagoras, direct consequence to the history of the thorax, who derived the veins from the (which was except that Galen, in developing the work of the to be Galen's view) and said that the arteries Thorax: first published as 10.1136/thx.33.2.153 on 1 April 1978. Downloaded from

156 R. K. French contain only air or spirit, , an opinion Herophilus and Erasistratus shared by Erasistratus and bitterly attacked by Galen. So the difference between arteries and veins Against this background we may briefly inspect was functional as well as structural. Herophilus what was said about the thorax and its origins by said that the arterial coat was six times as thick the two greatest of the Alexandrian anatomists as the venous, and Erasistratus, quite free from and physiologists, Herophilus and Erasistratus. It any ambiguities between nerves and other fibres, was Herophilus who said that arteries had tunics and between arteries and veins, elevated all three six times as thick as those of veins, and he was types of structure to the status of three great consequently struck by the arterial nature of the systems serving the body. The veins supplied '' connecting the heart and and by the nourishment, the arteries vital spirit, and the venous nature of the ''. "3 nerves psychic spirit; each organ of the body was tells us that Herophilus introduced the terms actually composed of the fine terminations of the 'arterial vein' and 'venous artery' for these vessels, three kinds of ramifying vessel. although Galen appears to claim them as his own The second important discovery of the pre- or invention.14 Galen also tells us that Herophilus early Alexandrian period was that of the cardiac wrote 'carelessly' about the cardiac valves, perhaps valves. We have seen that these structures are in retaining some confusion about the 'nervous' described in the work De Corde, which was once fibres associated with the valves; we may assume at attributed to but which was probably least that Herophilus recognised the functional written after Aristotle, perhaps in Alexandria. It direction of the valves. Thus in the fourfold is in the nature of a valve that it allows only a motion of the lungs (which uniquely in the body unidirectional flow, and this at once imposed had a motion independent of the nerves) air was severe constraints upon traditional ideas of the drawn into the lungs, from the lungs to the heart movement of blood and spirit through the heart. and body and back again, and lastly the air was We have seen that these ideas are somewhat vague expelled. We can probably assume that the incom- in the existing texts, but what is clear enough to ing air passed down the venous artery (pulmonary us is that some symmetrical relationship was held vein) into the heart, and thence via the to to exist between the lungs and the heart, blood the body. In the aorta and arteries this air or http://thorax.bmj.com/ and air being exchanged on both sides. But the spirit was mixed with blood. Given the functional valves changed all this, those of the vena cava on direction of the valves, however, we cannot see the right 'entering', and those of the aorta on the how this air was returned to the heart and lungs; left 'leaving' the heart. nor can we be certain that Herophilus allowed the These two discoveries involved the demise of cardiac valves to work 'properly' (in our sense). the traditional fundamental pair of blood vessels, The force of traditional ideas was such that many anciently assumed to run throughout the length of schemes of physiology contain allowances for them the body with symmetrically disposed branches to despite the discovery of the valves. Thus the on September 27, 2021 by guest. Protected copyright. the organs. The discovery that one of these vessels Hippocratic De Corde allows that the valves on was a vein (the vena cava) and one an artery (the the right side of the heart do not close completely, aorta), the assumed origin of the vena cava from allowing in some air from the lungs and maintain- the liver and the aorta from the heart, and the ing an ancient symmetry of blood and air ex- assumed function of the arteries of carrying spirit, change. We shall see that Galen's ideas on not blood, all combined to destroy the ancient bloodflow are an imperfect compromise of old symmetry. The picture was particularly compli- ideas and new discoveries, allowing an imperfect cated in relation to the vessels between the heart closure of the valves on the left of the heart. and the lungs: the vessel that arose from the heart Lastly, it is possible that we see the persistence of on the same side as the veins looked like an artery old ideas in Herophilus' notion that spirit enters but was considered to have a venous function as the body not only by way of the heart but from part of the great nutritive system of liver-vena all over the body.'5 This may be the idea, derived cava-heart-veins. Correspondingly, the vessel from , that tubes, or arteries, have between the heart and the lungs on the left, the open mouths at the surface of the body, drawing arterial side of the heart, looked like a vein but in air. Herophilus' study of the in diagnosis had to have the arterial function of the great res- and physiological theory seem to have been an piratory system of lungs-left ventricle-aorta- innovation. While the arteries originated in the arteries. The names 'venous artery' and 'arterial heart, Herophilus said he could not be certain of vein' thus came into existence during the Alex- the source of the veins.1' andrian period. In contrast, Herophilus' younger contemporary, Thorax: first published as 10.1136/thx.33.2.153 on 1 April 1978. Downloaded from

The thorax in history 2. Hellenistic experiment and human dissection 157 Erasistratus, located the origin of both veins and came to an end in Alexandria. The Ptolemy who arteries in the heart. He was in early life associ- reigned in the second half of the second century ated with the Aristotelians, and it may be that this BC expelled the , which perhaps anatomical suggestion is a sign of peripatetic hastened the decline of teaching. Rufus of influence.17 On the other hand, he believed in a Ephesus, writing at the time of Trajan, described form of the atomic theory, involving a belief in a human dissection in retrospective terms and had discontinuous vacuum and a rejection of 'hidden' to be content to dissect the , although recognis- causes. Nothing could be further from the ing that apes were more similar to man.22 Al- teleologically organised plenum that was though some Hellenistic texts23 mention Aristotle's world picture. Apollonius of Memphis as a dissector and a fol- Erasistratus seems to have been more interested lower of Herophilus (he antedated Galen) it is in the working of the body than was Herophilus, clear that by Galen's time the practice had ceased. whose achievements were primarily anatomical. Galen himself was in the midst of a revival of The fragments of Erasistratus' work on the Greek studies that began in the Roman world physiology of the thoracic organs are fortunately some 50 years before he was born.24 The part more detailed than those of Herophilus. Consistent played by Galen in searching out the spirit of with his anti-Aristotelian was his belief Greek medicine was his reverence for Hippocrates, that the body did not have (as Aristotle had said) his anxious pursuit of the pupils of the famous an innate pneuma, but that the ambient air (spirit Greek teachers of anatomy, and, it must be ad- or pneuma) was drawn in during inspiration, pass- mitted, his pretence that he, like Alexandrians, ing through the 'primary arteries'8 (the bronchi) had had the opportunity to dissect the human to the lungs, from the lungs to the heart, and body. The only human material routinely avail- from the heart to the body. This is an elabora- able to him was the skeleton while he was learning tion of the traditional idea of the arteries, heart, anatomy in Alexandria.25 Otherwise, it was only and lungs as a single . So taken fortuitous circumstances that furnished him with by this idea was Erasistratus that he insisted that glimpses of the anatomy of the soft parts, and the arteries contain only pneuma, unmixed with indeed much of his insistence on a systematic blood.'9 Once in the body, the pneuma underwent training in comparative anatomy and the dis- http://thorax.bmj.com/ two stages of concoction: in the left ventricle it section of animals reflected the need to prepare became vital spirit, which filled the arteries, and the mind for occasional access to human material. in the arteries of the brain it became psychic Galen's literary energy was immense, and a very spirit.20 Erasistratus simplified Herophilus' notion large proportion of his numerous medical works of the heart, regarding it as a two-chambered, not survive; his influence was enormous and for a four-chambered organ, the auricles being merely millenium and a half he was revered as 'The -shaped expansions of the vessels at their con- Prince of Physicians'.26

nection with the ventricles. This made it easier to Galen's system of physiology, as far as it relates on September 27, 2021 by guest. Protected copyright. regard one half of the heart as respiratory and the to the thorax, was an amalgam of his own dis- other as sanguineous or nutritive. As there was coveries and reasoning, and older ideas. A partial no communication between the two systems in the survival of the old idea of the body's fundamental heart or lungs, Erasistratus was in difficulty in pair of vessels is Galen's description of the vena explaining how blood emerges from a wounded cava as a long, continuous vessel arising from the artery, which he considered contained pneuma liver. The liver was the starting point of the body's only. He thought that the finest branches of the physiological processes, the site of the 'first veins, too narrow to admit blood, anastomosed coction' where the incoming food, transformed with the finest branches of the arteries, and that to chyle by the action of the and in- in certain circumstances, as when the arteries were testines and carried to the liver by the portal damaged and their pneuma escaped, blood was vein, was turned into blood, the food of the body. drawn into the arteries from the veins by the The body as a whole absorbed this blood slowly resulting vacuum. by the process of assimilation, literally 'making similar'-a process in which the Aristotelian Galen21 qualities of the blood were so disposed to convert part of the blood into body substance. In other Some time between the period of Herophilus and words, each tissue or 'similar' (homogeneous) part Erasistratus and that of Galen, who was born took from the blood what was necessary to it, about 129 AD in , the practice of human leaving a small proportion of residue to be elimin- dissection as a teaching and research practice ated. The entire venous system was thus like a Thorax: first published as 10.1136/thx.33.2.153 on 1 April 1978. Downloaded from

158 R. K. French d'etre of the veins, is produced elsewhere (the liver) and carried to the heart? Galen concluded that the vein-producing and vein-controlling faculty must be located in the same place as the faculty that produced and controlled the blood, for otherwise nature would be multiplying principles in vain, which she never does. There is little morphological difference between a cardiac origin and hepatic insertion of the vena cava on the one hand and a hepatic origin and cardiac insertion on the other. Galen had in mind a teleological and functional conception of a liver- vena cava-heart-veins body arrangement, the venous 'tree' that has to be translated into ana- tomical terms. This is one example of a very general occurrence in the , namely, that physiological considerations very often determine anatomical statements. Finally, there are technical reasons why Galen may have been encouraged to think of the vena cava as a long, continuous vessel. Unable to dissect the adult human body, he was obliged to use Fig. 1 Galenic cardiac physiology. For explanation were able see text. apes. It is possible that he and Aristotle to dissect human fetal material; in some apes and in the young human, the vena cava does have the tree,27 the trunk of which was the vena cava, appearances of a straight, continuous vessel pass- planted in the liver and supplying blood to all parts ing through the right auricle and thus inosculating of the body with a slow, unidirectional motion with the heart (Fig. 2). http://thorax.bmj.com/ through its branches. Thus the body was supplied with blood through It follows that for Galen, unlike other writers the branches of the vena cava arising above the such as Aristotle, the vena cava did not arise in point B in Fig. 1. As observed, each tissue took its the heart, nor indeed did the heart interrupt the proper aliment, the substance that resembled structure of the vessels as it passed along the body, it most, from the blood. Yet there was one ex.- for the vena cava merely inosculated with the ception. The (always spoken of by Galen as heart by means of the intermediary right auricle, a single bilobed organ),29 constructed of ex-

which Galen regarded simply as a sinewy ex- ceptionally light and frothy substance, needed very on September 27, 2021 by guest. Protected copyright. tension of the vein. This arrangement is shown in light and subtle blood for its nourishment. the diagram (Fig. 1), where AB indicates the vena Ordinary venous blood direct from the liver was cava arising from the liver and passing the heart, too heavy and coarse, and Galen therefore sup- and C its opening into the right auricle. The posed that that part of it destined for the lung entire venous 'tree' is in line with the older idea underwent a second concoction in the right of the 'nutritive' (venous) system as opposed to the ventricle of the heart, which it entered through 'respiratory' (arterial), and it enabled Galen to the opening of the vena cava into the right auricle agree with the old-fashioned accounts (which we (C in Fig. 1) and through the valve (D in Fig. 1). met in the first article) of the vascular system This preparation of the blood was the sole func- given by his idols, Hippocrates and Plato,28 and to tion of the right ventricle, executed by a specific reject those who opposed them, including 'faculty', a name Galen always used for a unique Erasistratus. In fact Galen's rejection of Erasis- biological process about which little else was tratus' claim that the veins, like the arteries, arise known. After concoction this blood was supplied in the liver is illuminating. Erasistratus was aware to the lung through the vessel E (the pulmonary of the valves that point into the heart at the attach- artery), which Galen considered to be a vein ment of the vena cava (we are now considering, because it carried venous blood. He adopted the with Galen, the heart as a two-chambered organ) Alexandrian name of 'arterial vein' because he and which govern the flow of fluids into the heart. saw clearly that the vessel had an arterial How, asks Galen, can the heart be the centre of structure. Galen did not accept that this structure the venous system when the blood, the raison was anomalous but argued that the thicker coat Thorax: first published as 10.1136/thx.33.2.153 on 1 April 1978. Downloaded from

The thorax in history 2. Hellenistic experiment and human dissection 159 Alexandrian vivisectional experimental method, he proved his case by experiment.31 He ligated an I exposed artery of an animal in two places to pre-

,-1 It'lt.I.1,1 'tT11S1 'u\ ai vent subsequent inflow of blood from the veins (the Erasis4rateans' argument) and opened the

A 1 tFii I,. hif t It I1 artery between the ligatures. Of course he found )rf1lIce ofr ',IIII -1 'l, it was full of blood and, like others, he was able to L'. V'ell:t (:;i%,;t distinguish between arterial and venous blood by their colour and the force with which they flowed in their vessels. But now Galen faced a difficulty. The two vascular systems were quite separate, one in the traditional fashion concerned with nutrition, the other with the respiration of spirit. He insisted that the arteries contained blood but denied trans- ovli ference of blood from the finest branches of the veins to those of the arteries in the way described by Erasistratus. There was for Galen no way of getting blood from its only place of production, the liver, into the arteries. With hindsight we can see it would have been a simple matter for him to have supposed that blood crossed the lungs and entered the heart through the pulmonary vein (the venous artery), but Galen had already denied a > _ {>x~~~~~litedele of l)a_ iI~~~~~tr|ial W11 venous-arterial exchange of blood. To have -ltlf i V I;t Ci L\V postulated one in the lung would have been, in addition, to obscure the traditional distinction be- tween the nutritive and respiratory systems. More- over, the lung, like all parts, absorbed the blood http://thorax.bmj.com/ Fig. 2 The vena cava seen as a continuous vessel coming to it as nourishment. passing through the heart (modified from In order to avoid this difficulty, Galen postulated Cunningham's Manual of Practical Anatomy, the existence of pores in the interventricular reproduced by permission of the publishers). septum of the heart, so that a small quantity of venous blood could be transferred to the left of the vessel was designed to prevent the escape ventricle at F (Fig. 1). The left ventricle was a of the highly rarefied venous blood it contained. traditional seat of the soul in Greek medical

In this way the whole of the body was supplied thought (compare De Corde), and Galen placed on September 27, 2021 by guest. Protected copyright. with nourishment. Yet, in accordance with tra- it in a Vital Faculty, which transformed the ditional ideas, Galen held that the body must not incoming venous blood into arterial blood, which only be nourished but vivified; it had to be carried to the body through the arteries. governed not only by a nutritive faculty but by a The concoction that produced arterial blood neces- vital faculty, giving heat, life, and motion. We sarily required the inspired air or spirit of the may recall the fundamental physiological observa- outside world. Galen urged that air in substance, tions of the living and dead body with which this or its insubstantial quality, passed down the series of articles began, and also the resultant venous artery G (Fig. 1) from the lung to the left hierarchy of living principles or souls formulated ventricle. This life-bearing pneuma was trans- by Plato and Aristotle. The soul responsible for formed in the left ventricle into vital spirit, vivication, heat, and motion was the inspired air- pneuma zotikon, the essential component of or spirit-soul, and the system serving it in the body arterial blood. As in all concoctions, there were was the respiratory, that is, the arterial. We have residues to be expelled, here 'fuliginous vapours', described above how by Galen's predecessors the whose only route of escape was back up the lungs, heart, and arteries were considered as a arterial vein to the lung and outside world. single system. Galen accepted this, but with a very important reservation: he insisted that the arteries THE CARDIAC VALVES contain blood, not simply spirit. He wrote a book30 Yet, in solving his first difficulty in this way, Galen to refute Erasistratus on this point and, using the found himself with another. Spirit passed down Thorax: first published as 10.1136/thx.33.2.153 on 1 April 1978. Downloaded from

160 R. K. French through the venous artery into the left ventricle the arteries were for Galen the organs of respira- through the valve now called the mitral. It was tion, drawing in air or external pneuma and con- clear to Galen and others that the functional verting it to bodily pneuma. It followed that the direction of this valve is into the heart, but Galen pulmonary vein was regarded as an artery, and was obliged to allow passage in the reverse direc- because it looked like a vein Galen adopted the tion to the escaping fuliginous vapours. Moreover, name 'arterial vein' for it. Its thin tunic, he the lung, like all parts of the body, needed arterial argued, allowed it to be compressed during the blood, which could reach it only from the left contraction of the thorax in breathing to aid the ventricle in opposition to the natural direction of passage of its fluids. The normal function of the mitral valve. the thick arterial coat was to transmit the active So Galen had three different substances, arterial wave of dilatation, which Galen considered the blood, spirit, and sooty wastes, moving in two dif- pulse to be; the venous artery, moved by the ferent directions across a valve whose natural thorax, had no need of a pulse or thick tunic. direction favoured the motion of only one of them It is puzzling for the modern reader to under- and that the least substantial-spirit, or the stand why Galen did not simply allow that blood quality of air. This part of Galen's cardiac crossed the lungs, which would at once have physiology drew the criticisms of later natural removed the difficulties of the perforate septum, philosophers and of historians. It caused Harvey the anomalous structure of the pulmonary vessels, to cry 'Good God! How do the mitral valves and the 'incompetent' mitral valve. This step was hinder the return of air, and not of blood?'32 But indeed the first advance from Galenic physiology, Harvey knew what a valve was, and those his- made apparently independently three times before torians who discuss the 'incompetence' of Galen's Harvey, but to ask why Galen did not take it is, as mitral valve are anachronistically reading back to we have seen, to ignore the power of the tra- Galen their own knowledge of valves. Galen's ditional ideas which Galen took to be established. attention was given to the flaps of the valve, the The problems which we see in his account were membranarum epiphyses, not to the whole struc- for him successful modifications imposed upon ture of the valve. Every concoction, every ex- the old ideas by the recent discoveries of the change of materials in the body was accompanied Alexandrians. http://thorax.bmj.com/ by some residue, some superfluity, for no substance In contrast, Galen's ideas on the nervous system ultimately derived from food was entirely pure. It did not depend on ancient ideas and on the revered followed that all the cardiac valves allowed some Hippocrates but on comparatively recent work, reverse flow, and the mitral valve was particularly much of it based on vivisectional experiments, notable in this respect because of the intensity of both his own and of the Alexandrians. There was the concoction in the left ventricle, and because no weight of traditional ideas to labour under, and it had fewer flaps. Galen had no other notion of Galen's description of the nervous system is much what a valve was other than the flaps of the heart. more successful in modem eyes than that of the on September 27, 2021 by guest. Protected copyright. Although he repeatedly used the analogy of a heart. Broadly, the central nervous system for bellows to explain how the heart attracted sub- Galen represented the highest category of the stances, they were valveless bellows. Not until traditional hierarchy of three-fold governance of shortly before the time of Harvey were valves well the body, the lower two being the nutritive and enough known in other fields (in water mills, in the vital. Just as the vital faculty of the heart and pumps of fire engines, in the veins, and in the arteries depended on the nutritive, so the vital intestine) for the 'incompetence' of Galen's mitral faculty provided material for the rational or valve to stand out in contrast. Although Galen 'animal' faculty of the brain. Arterial blood seems only to have described the mechanical ascended through the carotid arteries to the rete reasons for the opening and closing of the flaps, mirabile, a network of arteries which Galen (and the forces impelling the passage of the fluids the Alexandrians) found above the basilar bone of through the valve were the purely biological the skull of certain domestic animals and attri- Faculties of attraction, retention, and expulsion, buted to man. In it the finely divided blood, said which were entirely non-mechanical. So Galen's Galen, underwent a second concoction, with air whole idea of the movement of the fluids of the drawn in through the nose into the ventricles of heart was sui generis, and he does not deserve all the brain, to produce the second of the bodily the censure normally levelled at him. spirits, pneuma psychikon, 'animal spirits'. This pneuma filled the substance of the brain and THE SPIRITUAL AND ANIMAL ORGANS nerves and served the power of motion and the The left side of the heart, the pulmonary vein, and faculties of sense. Thorax: first published as 10.1136/thx.33.2.153 on 1 April 1978. Downloaded from

The thorax in history 2. Hellenistic experiment and human dissection 161 By dissection and vivisection Galen traced out observation, and his anatomy is very detailed.40 the course of the cranial and spinal nerves and He described the rami communicantes41 of the showed how such anatomical knowledge was spinal nerves but did not discover the sensory and essential to medicine. It is his most powerful motor function of the different roots. attack against the Empirics, and he illustrates it In exploring the nerves of the thorax Galen paid by the story of a patient who had fallen from his some attention to the vagus and sympathetic conveyance on his way to , damaged the trunk on their journey through the chest. He did vertebrae at the bottom of the neck, and lost the not always clearly distinguish between the two use of three fingers. The Empirics applied their nerves, sometimes describing the sympathetic remedies where they found the symptoms. Galen trunk as a branch of the vagus, and always re- treated the origin of the nerves at the vertebrae garding it as a cranial nerve, the sixth of the seven and effected a cure.33 pairs of the enumeration he adopted from his Another story of which Galen was proud was teacher, Marinos. The earliest account he gives of that of his discovery of the recurrent laryngeal the sixth pair is in On the Use of the Parts,42 and nerve. He tells34 how a , excising a tumour it is largely based on the nervous anatomy of of the neck, cut too deep and rendered his patient domestic animals. Consequently, the nerve he half dumb. Galen was able to reproduce the situ- describes is single down to the level of the top of ation experimentally in a living pig; by tracing the the thorax, the common vagosympathetic trunk of nerve from the brain to the vocal organs he a number of animals including the horse and the showed its structure as an organ of voluntary pig.43 The purpose of both nerves for Galen was motion. By gently squeezing the nerve of both to give sense and motion to the abdominal viscera sides he was able to deny the pig its voice for as and lower organs; accordingly, both nerves were long as he pleased and then to permit its re- obliged to travel over a great distance from the covery.33 His experimental analysis extended to head, and as it was in the nature of a nerve to be the control of all thoracic motions.36 soft, they had to be defended against damage on In tracing out the anatomy of the recurrent their journey. This is the reason, says Galen, for laryngeal nerve Galen was struck by the fact that the plexuses and ganglia he saw on the sixth it descends to the thorax and folds itself over pair, and for the attachment of the sympathetic http://thorax.bmj.com/ thoracic structures before ascending again to its trunk to the spinal nerves 'at the roots of the proper destination in the throat. His answer lay in ribs'. the general principle that nerves, being soft, were This account of the thoracic parts of the sixth always inserted into the end of the muscle that pair shaped all anatomical opinion until, and after, moved the least, in order to avoid damage. The Vesalius. It became formalised in the statement top of the vocal organs was more mobile than the that the sixth pair descended to the level of the bottom, and therefore the nerve had to approach first rib and divided into three branches, the it from below: but a long, soft nerve needed sup- 'stomachic' (the vagus), the recurrent laryngeal, on September 27, 2021 by guest. Protected copyright. port over such a distance, and so nature contrived and the 'costal' (the sympathetic). The costal was to support it upon the thoracic arteries. so called because of its connection with the spinal Another experiment of Galen's,37 as striking as nerves to the muscles of the ribs, the intercostals. that upon the recurrent laryngeal nerve, was the Later the 'costal' for the same reason became serial section of the . Again, the living known as the 'intercostal', which led in the 17th pig was secured to the operating table and a scalpel century to confusion with the true intercostal was inserted between each vertebra to destroy the nerves that Galen had described adequately. In longitudinal fibres. Beginning above the sacrum,38 the later On Anatomical Procedures, based on Galen repeated the operation at every vertebra apes, Galen has a much clearer picture of the and carefully noted the results. In this way he was separate paths of the vagus and sympathetic trunk able to establish the distribution of the spinal in the neck and thorax. nerves and the manner of their control of the We have already seen that Galen rejected the organs: he noted the progressive loss of sense Aristotelian notion that the nerves arise from the and motion as the operation proceeded through heart. We have also seen that this may in fact be the thoracic vertebrae into the cervical. In parti- based upon something of a misunderstanding of cular, he was able to isolate the nervous control Aristotle's position, because, in his day, nerves of the various parts of the motions of respiration, were not clearly distinguished from other fibres. making the animal breathe by the intercostal At all events, Galen's rejection of Aristotle is part muscles or by the diaphragm alone. In these ex- of his wider attack on the whole notion of cardio- periments Galen exhibited an acute power of centricity. He devoted a large part of his book on Thorax: first published as 10.1136/thx.33.2.153 on 1 April 1978. Downloaded from

162 R. K. French the opinions of Plato and Hippocrates44 to estab- in both adult and fetus blood crossed the septum, lishing the supremacy of the brain as a centre of that the flow of blood in the veins in the bulk of control. So strong was the idea of nervous control the body was centrifugal, not to the heart as in of muscular motion, and so anxious was Galen modern physiology, and, lastly, in specific refer- to deny nerves to the heart, whether leaving it or ence to the fetal condition he imagined that entering it, that he denied that the heart was a maternal blood crossed the placenta to supply the muscle. Instead, he claimed that it moved by fetus. Even with these constraints upon his inter- means of its own unique, innate Pulsific Faculty, pretation of fetal bloodflow Galen was able to and its motion was natural,45 arising from the explain in a way that fitted admirably with the rest 'nature' of the heart, not animal, the motion of of his physiology how the particular needs of the the skeletal muscles arising from the will (anima fetus were met. The fetal lungs, deprived of air, in the Latin tradition). This action of the heart had no need of an adult vascular supply, and the was one of expansion, not contraction, so that needs of the fetus were met by the maternal blood, the active phase of the heart's motion was diastole. which completely bypassed the fetal heart, the This was the basis of his analogy with the black- action of which was unnecessary in the fetus; it smith's bellows, which were forcibly opened by the beat but did not expel its contents.48 smith, drawing in air through the same nozzle Galen assumed that the maternal venous blood, that also fed the fire: the heart drew in blood flowing through the umbilical vein, reached the from the vena cava, and, in turn, the actively fetal liver and rose to the heart through the vena expanding arteries drew in the heart's blood with cava in the usual way, from A to C (Fig. 1). Since a pulse derived from the heart. the fetal lung was not functioning, Galen supposed Here Galen is consciously disagreeing with that there was no need for the right ventricle to Alexandrian opinion, which said that the heart exercise its only function, that of preparing blood contracted forcibly, expressing its contents. His for the lung. The blood consequently did not enter opinion, however, agrees with a wider notion in the right ventricle but passed directly through the his physiology: voluntary muscles were composed open foramen ovale (obscured in the diagram fibres which contracted, by the vessels) into the left auricle (H, Fig. 1). only of longitudinal http://thorax.bmj.com/ physically pulling the tendons and bones, but the Since Galen considered the auricles simply as hollow organs of the viscera46 were composed of sinewy expansions of the vessels, the blood in this three different kinds of fibre, and acted by means transit did not pass through the heart at all but of Faculties that were essentially biological and ascended from the left auricle to the lung through not physical. Each hollow organ was composed of the venous artery (G, Fig. 1), which not only longitudinal or straight fibres, which exercised a looked like a vein but also in the fetus carried Faculty of Attraction, circular fibres that enabled venous blood. the Expulsive Faculty to eject the contents of the Maternal arterial blood, said Galen, entered organ, and transverse fibres, which, in a con- along the route umbilical arteries-fetal iliac on September 27, 2021 by guest. Protected copyright. certed action with the other two, retained the arteries-fetal aorta. From the aorta it was dis- contents.47 All these Faculties were subdivisions of tributed to the body in the usual way, with the the Nutritive Faculty and were primarily exercised exception of the lungs. Since the fetus was not in the organs of nutrition. Although the left ven- respiring, the whole lungs-heart-arteries respira- tricle was the home of the Vital Faculty, the tory system of the adult was fed from the lower right ventricle was part of the venous-nutritive end, and its functional direction was reversed in system that Galen said was controlled by 'nature'. the fetus. Approaching the heart in the aorta at I In saying that the motions of the whole heart and (Fig. 1), the maternal arterial blood had no need the arteries were 'natural', Galen meant that they to enter the fetal heart, the left ventricle of which were not controlled by the rational soul or the was not engaged in the production of spirit; in any psychic faculty in the brain. case, the aortic valve would have prevented any substantial flow. The only route for the arterial THE blood to reach and vivify the lung was across the THE MOVEMENT OF THE HEART AND BLOOD IN the FETUS fetal ductus arteriosus J (Fig. 1) and up Apart from the invisibly small septal pores, arterial vein, which consequently in the fetus not Galen's description of the anatomy of the heart only looked like an artery but carried arterial arteriosus blood. At birth the umbilical bloodflow stopped, was precise. He knew of the fetal ductus and and the foramen ovale and their fate at birth. Yet air entered the lungs, and the foramen ovale his physiology of fetal bloodflow contained three ductus arteriosus closed, producing a normal adult major errors in modern terms: he imagined that Galenic bloodflow. Thorax: first published as 10.1136/thx.33.2.153 on 1 April 1978. Downloaded from

The thorax in history 2. Hellenistic experiment and human dissection 163 Conclusion of the appearances, of the nature of his biological interpretation as a whole, which has two aspects. Galen stands at a critical point in the development Firstly, Galen discussed scientific procedure in of biological science. The Hellenistic descriptive making discoveries but, secondly, he knew in ad- and experimental tradition was summarised and vance what kind of thing he was going to discover. extended in his description of the of He wrote a book on , of which the heart and the changes occurring in the fetal he was proud and which has been lost. It seems heart at birth, which is accurate enough by to have included discussion on inductive general- modem standards. In that sense Galen's account isations from sense experience, and also much on of the heart looks forward to modern medicine. deductive reasoning, on the pattern of geometry, Yet his account of the functioning of the adult from certain irrefutable axioms. Whenever we heart was almost entirely dominated by traditional read about 'reason' in old texts on anatomy and ideas, which we met in the first article. In other physiology we may be sure it is axiomatic, deduc- words, Galen did not derive his ideas on function tive reasoning that is being referred to. These from those on structure; nor, indeed, did any axioms reveal a great deal about the world-picture other student of the human body, for almost in- of the writer; they are the ideas from which his variably in the history of anatomy and physiology reasoning started and were themselves incapable ideas of function have either instituted or modified of proof or rejection by reason. Broadly, they anatomical statements. For example, Galen's des- represent the kind of thing Galen knew he was cription of the interventricular cardiac pores is going to find by applying the Aristotelian inductive matched by his account of an anatomical pathway or the Alexandrian experimental method. (Galen's from the nose to the ventricles of the brain, and experimental method was not entirely modern. for the escape, in the reverse direction, of the Most often his experiments are designed to prove waste products of the concoction of animal someone else's ideas wrong; and so are part of a spirits.48 general mode of proof by rejecting all known This problem of the relationship between form alternatives. He does not use experiment to 'see and function is highlighted by the case of the what happens' or to establish his own uncontested heart, which is a complex structure. Indeed, the ideas. An excellent possibility here would have http://thorax.bmj.com/ mammalian heart is unnecessarily complex and been to inject water into the right ventricle to arose as a four-chambered organ with a 'figure of demonstrate the pores of the septum.) eight' circulation from the evolutionary accident So, in purely medical topics, Galen uses the that the primordial lungs that were to take over axioms of contraries-cure-contraries as the basis the function of the ancient gills, as the ancestor of his therapeutics so that with the of air-breathing animals moved out of the sea, fundamental Elemental Qualities of Wet and Cool already had their own blood supply with a venous are used in Hot and Dry diseases. In anatomy and return direct to the heart. This venous blood came physiology, Galen's most fundamental conception to be arterial and in order to provide efficient cir- was that of Nature as the Creator of the body. on September 27, 2021 by guest. Protected copyright. culation, should have gone directly to the body, Unlike the Christian conception of a Creator, but the existing pathways could not be abandoned, Galen's Nature was not omnipotent and had cer- so the arterial blood returned to the heart to be tain recognisable characteristics. She was bound sent out again. The four chambers of the heart by the Necessity, such as the nature of the evolved as a complex device to handle the double materials she was working with, she was endued circulation. Further, the major changes taking with Reason, handling the Qualities of the place in the chambers, vessels, and fluids of the materials in the best possible way, and she was fetal heart at birth are an additional complexity benificent, always bearing in mind the well-being also due to the secondary development of air- of the animal and of the species. Being reasonable, breathing in evolutionary history. They are neces- Nature never duplicated her efforts by doing sary to adapt the already secondarily complex something unnecessarily; 'Nature does nothing in four-chambered heart from an aqueous to gaseous vain' is Galen's most frequent axiom in reasoning environment. about the structures of the body and their func- It would not be difficult for a hydraulic engineer tion. That the structure of the heart was unneces- to design a simpler and more efficient organ and sarily complex, that some mindless process of circuit of circulation, and it is no surprise that had caught up the chambers and vessels Galen's interpretation of the structure does not of the heart in an irreversible complexity, and that match the modern account. His interpretation is any competent engineer could do better, would all a very good example, because of the complexity have been entirely foreign to Galen's way of Thorax: first published as 10.1136/thx.33.2.153 on 1 April 1978. Downloaded from

164 R. K. French thinking. His knowledge of comparative anatomy contents (part of the Formal Cause); and the told him that animals without lungs did not have Efficient Cause just mentioned, Hot and Cold. a right ventricle, but these animals were 'imper- With this framework Galen must have been con- fect', not merely simpler. His knowledge of animal fident of his position, and he could afford to be form also told him that there was a single Mind scathing about those who attempted to explain that fashioned all of nature. The guiding principle the anomaly of the pulmonary vessels without behind all his anatomical and physiological re- Reason, Necessity, or Causality. Thus he attacks, search was to discover the rationality of Nature. with his customary gusto, the opinions of Lastly, let us see how this principle worked in Asclepiades, who had argued that the venous Galen's analysis of the thoracic organs. He saw arteries of the lung (the pulmonary veins) were the invisibly small septal pores of the heart with thin-walled because they worked twice as hard as 'the eye of reason', arguing that the clearly visible other arteries in having a double motion-one but apparently blind pits on the wall of the right from the lungs in respiration and another from the ventricle must in fact perforate into the left pulse. The arteries in the rest of the body, on the ventricle, otherwise the pits would be without other hand, move moderately with their own function; but Nature does nothing in vain, and motion and so grow well-nourished and strong. nothing in the body is without function, therefore The veins in the body as a whole, continued the pits are perforate. We have already seen that Asclepiades, do not move and so waste away like Galen's physiological theory dictated that nerves a lazy slave who takes no exercise, but the arterial entered the least-moving end of a muscle, and so vein of the lung does move, and so grows strong.5' the recurrent laryngeal nerve had to descend to However much Galen's teleology disagrees with the thorax in order to approach the vocal organ modern evolutionary theory, it is clear that he was from below. But one of the Necessities that philosophically much better equipped than some Nature labours under is that nerves are soft even of his immediate predecessors. though they have to be stretched over long dis- Another form of Necessity constraining Nature tances. As we have seen, such nerves as the vagus in constructing the body in Galen's system was the and sympathetic trunk were consequently opposing Qualities of neighbouring parts. In equipped by Nature with ganglia and plexuses to general, a hard part had to be separated from a http://thorax.bmj.com/ hold them steady on their course, and the recur- soft, lest it damage it, by a third part of middling rent laryngeal was supported by Nature with the softness. Thus the comparatively soft and very aorta on one side and the subclavian artery on the noble heart would be damaged by its proximity to other (as an inferior substitute). the sternum, were it not for the pericardium, a Galen is very clear about the roles of Reason membrane of intermediate nature.52 'Nobility' was and Necessity in the creation of the pulmonary also a concept that played a part in Nature's vessels. Nature's reason in creating them was to reason, the more noble organs being those that take air to the heart and blood to the lung; the housed the higher faculties. They were con- Necessity that constrained Nature was the ele- sequently given precedence in position in the on September 27, 2021 by guest. Protected copyright. mentary qualities of Moist and Dry, which Nature body, organs of less importance being displaced blended together to produce a plastic, waxy sub- from their own ideal position. stance. Drying out some parts with the Hot and stiffening others with the Cold, Nature formed Notes and references the rudiments of the vessels.50 Galen identified five causes in all such changes: the material, from 1 Edelstein, L. Ancient Medicine, Baltimore, 1967: which the organ was made; the efficient, the The history of anatomy in antiquity, pp. 247-301. immediate instrument (Hot and Cold); the formal, 2 Galen, Anatomical Procedures, trans. Singer (cf. or shape of the product; the final, the purpose of note 3), p. 31. the whole operation; and, lastly, the Creator or 3 Galen tells us about Diocles' text in On Anatomi- frame- cal Procedures, trans. Singer, C., Oxford Univer- Nature herself. Within this philosophical and work Galen had to explain the anomalous struc- sity Press, 1956, p. 32. For the dating to fragments of Diocles, see Jaeger, W., Dlokles von ture of the pulmonary vessels. We may refer Karystos, Berlin, 1938, summarised in Etnglish in the account of these vessels given above and recall The Philosophical Review, 49(1940), 393-414. the Final Cause, Nature's reason, the exchange 4 The evidence for human dissection by the Alex- of fluids; the Material Cause, the constituent andrians has been disputed. The most important material, with the added Necessity of the vein source is Celsus-in the proemium to his De being thick-walled to retain its fine blood and the Medicina (there is a by W. G. Spencer artery being thin-walled to aid the expulsion of its in the Loeb series, London, 1935)-who is probably Thorax: first published as 10.1136/thx.33.2.153 on 1 April 1978. Downloaded from

The thorax in history 2. Hellenistic experiment and human dissection 165 the source of many later comments, such as those Callisthenes, and Herophilus are jointly credited of , who called Herophilus a butcher with discovering a number of things about the eye, who cut up 600 people (see the tenth chapter of including the technique of excising it and the De Anima in the edition of J. H. Waszink, Amster- arrangement of the optic nerves. Comparison of dam, 1947, p. 13). Tertullian, however, also this passage with that of earlier editions, such as depends in part upon Soranus, an opponent of dis- that of Meursius (I. Meursius, Chalcidii V.C. section and a possible source of antivivisection de Platonis translatus, Leiden, 1617, p. opinion. The whole question may have come into 230), suggests that it cannot be interpreted to show prominence as a result of its adoption as a topic that Alcmaeon removed the eye and dissected out in rhetoric. Another classical source is Rufus of the optic nerves; it is very likely that Alcmaeon is Ephesus (it has been translated by A. J. Brock included in this list of authors on the basis of his in his Greek Medicine, London, 1929, p. 126), and excision of the eye. Chalcidius' description of the these accusations were repeated in the middle optic nerves agrees with what Galen tells us of ages by St. Augustine and Vindicianus. The pseudo- Herophilus' knowledge of them, and it is very (and post-) Galenic Finitiones Medicae speaks of likely that Chalcidius' description of the optic the Rationalists' advocacy of vivisection as if the nerves derives from Herophilus. Chalcidius' ac- debate were still a live issue. Later medieval count, however, includes a description of the junc- sources report that the Alexandrians vivisected tion of the optic nerves, which thus appears to be a first the nervous system, then the organs of respira- discovery of Herophilus, not mentioned by Galen tion, including the heart, and lastly the organs and previously unknown to historians. (On the of nutrition. This reflects the philosophical prece- possibility of Alcmaeon performing , see dence of the nobility of the different organs, and Lloyd, G. E. R., 'Alcmaeon and the early history so may be a medieval rationalisation of the clas- of dissection', Sudhoffs Archiv, 59(1975), 113-147; sical practice, but it is also the most profitable Galen's description of Herophilus' account of the sequence in which to employ vivisection, leaving optic nerves is in the edition of the Opera Omnia until last those organs that continue to function edited by Kuhn, , 22 vols; vol. 3, p. 812). the longest. 13 Rufus of Ephesus, De Apellationibus Partium 5 Strictly, the Empirical sect best known to later Corporis Humani, in Estienne, H., Medicae Artis historians and to Galen was founded by Philinus Principes, , 1567, vol. 1. of Cos, a pupil of the major Alexandrian figure 14 Ed. Kuhn, vol. 5, p. 549. Herophilus, but empirical attitudes were certainly 15 Galen, ed. Kuhn, vol. 4, p. 731. http://thorax.bmj.com/ debated during the period of the formation of the 16 Galen, ed. Kuhn, vol. 8, p. 703. , and the later empiricists con- 17 See Lonie, I., 'Erasistratus, the Erasistrateans, and sciously compared their ideas with the empirical Aristotle', Bull. Hist. Med., 38(1964), 426-443. Hippocratic writings. 18 Galen, ed. Kuhn, vol. 4, p. 706. 6 See Jaegar, W., Aristotle. Fundamentals of the 19 Wilson, L., 'Erasistratus, Galen and the pneuma', History of his Development, trans. by R. Robinson, Bull. Hist. Med., 33(1959), 293-314. Oxford, 1948. 20 Galen, ed. Kuhn, vol. 5, p. 185. 7 Steckerl, F., The Fragments of Praxagoras of Cos 21 Good general accounts of Galen and his work are

and his School, Leiden, 1958, p. 34. Temkin, O., Galenism, Cornell University Press, on September 27, 2021 by guest. Protected copyright. 8 Lloyd, G. E. R., Aristotle: the Growth and Struc- 1974, and Sarton, G., Galen of Pergamon, Kansas ture of his Thought, Cambridge, 1968, p. 72. University Press, 1954. More specialised accounts 9 On the use of the technique in teaching see are those of Walsh, J., 'Galen's studies at the Kudlien, F., 'Medical education in classical an- Alexandrian school', Ann. Med. Hist., 9(1927), tiquity' in The History of Medical Education, ed. 132-143; Prendergast, J., 'The background of C. D. O'Malley, University of California Press, Galen's life and activities, and its influence on his 1970, p. 11. achievements', Proc. Roy. Soc. Med., 23(1930), 10 See Matter, M. J., Histoire de l'Ecole d'Alex- Sect. Hist. Med., 1131-1148; Harris, C., The Heart andrie, Paris, 1844, vol. 3. and Vascular System in Medicine, 11 Largely reported by Galen. They have been Oxford, 1973; and Hall, A. R., 'Studies in the collected by Dobson, who sometimes includes too history of the cardiovascular system', Bull. Hist. much of the Galenic context. Dobson, J., 'Hero- Med., 34(1960), 391-413. A great deal of Galen's philus of Alexandria', Proc. Roy. Soc. Med., 18 system of medicine and physiology has been (1924-5), Sect. Hist. Med., 19-32; Dobson, J., covered in a number of volumes by R. Siegel, who 'Erasistratus', Proc. Roy. Soc. Med., 20(1927), is perhaps too inclined to interpret Galen in Sect. Hist. Med., 21-28. See also Jones, W. H. S. modern terms. (Galen's System of Physiology and The Medical Writings of Anonymus Londinens, Medicine, , 1968; Galen on Sense Perception, Cambridge, 1947, which contains a useful discus- Basel, 1970). sion of the physiology of the two Alexandrians. 22 Rufus of Ephesus, The Names of the Parts of the 12 The passage from Chalcidius is given in Diels, H., Human Body, the relevant part of which is in- Die Fragmente der Vorsokratiker, Berlin, 1934, cluded in English translation in Brock, A. J., Greek 3 vols.; vol. 1, p. 212. In this passage Alcmaeon, Medicine, London, 1929, p. 126. See also Darem- Thorax: first published as 10.1136/thx.33.2.153 on 1 April 1978. Downloaded from

1.66 R. K. French

berg's edition of 1879, p. 149, and the p. 285). However, Galen describes a non-respiratory Latin version of Estienne (cf. note 13). 'fifth lobe' of the lung, constructed solely, he says, 28 The Introductio seu Medicus and the Finitiones to support the vena cava in its passage through the Medicae: both are included, as pseudo-Galenic, in thorax; this lobe is a simian feature, illustrated in the Venice, 1625 (Junta) edition of the Opera Singer's tran:lation of the first half of On Ana- Omnia of Galen in the class 'Isogogici Libri'. tomical Procedures (p. 273). 24 Prendergast, loc. cit. 30 An in arteriis sanguis contineatur. 25 Galen, On Anatomical Procedures, trans. C. 31 See Harris (note 21) p. 268. Singer, p. 3. 32 Harvey, W., The Circulation of the Blood, trans. 26 Galen's most important surviving anatomical and K. J. Franklin (Everyman ed.), London, 1963, p. 17. physiological works are On Anatomical Procedures, 33 Kuhn's ed., vol. 8, p. 58. the first half of which survives in Greek and has 34 Kuhn's ed. vol. 8, p. 55; Duckworth's translation been translated by Singer (cf. note 3) and the of On Anatomical Procedures, p. 76. See also second half of which survived only in . This Walsh, J., 'Galen's discovery and promulgation of is available in English translation (by WV. H. L. the function of the recurrent laryngeal nerve'. Duckworth), Cambridge, 1962. On the Use of the Ann. Med. Hist., 8(1926), 176-184. Parts of the Body is Galen's major philosophical 35 Duckworth's translation of On A natomical Pro- and functional interpretation of structure; see the cedures, pp. 91, 106, 107, 210. translation by M. T. May, Galen on the Usefulness 36 Book 8, Chapter 5 of On Anatomical Procedures: of the Parts of the Body, Cornell University Press, Singer's translation, p. 211. 1968 (2 vols). These two Galenic texts contain the 3 Galen seems to have enjoyed working before an fundamentals of his thoracic anatomy and physi- audience, and no doubt appreciated their reaction ology, including experimental vivisection of the to the spectacle of a secured and noisy pig being nerves. The biological powers that are the funda- dramatically silenced. He tells us how he was asked mental principles of his physiology are discussed to perform the experiment before a group: Kuhn's by Galen in On the Natural Faculties, which has ed. vol. 14, p. 626. been translated by A. J. Brock in the Loeb series, 38 Duckworth's translation of On Anatomical Pro- London, 1916. Galen's specialised tracts on aspects cedures, pp. 20-24. of thoracic structure and on thoracic medicine are 39 Singer's translation of On Anatomical Procedures, not so well served by English translation. He wrote pp. 211ff. On the Cause of Respiration (Kiuhn's ed., vol. 4, 40 His material for these experiments was the Barbary http://thorax.bmj.com/ pp. 465-469), On Difficulty of Respiration in three ape, and until very recently it has been impossible books (Kuhn, vol. 7, pp. 753-960), and On the to confirm just how precise his anatomy was be- Use of Respiration (Kuhn, vol. 4, pp. 470-51 1). cause of the modern rarity of this species. The 27 Kuhn's ed., vol. 5, p. 525. American anatomist, C. M. Goss, has recently 28 Galen discusses the opinions of Hippocrates and been able to follow Galen's dissections on an em- Plato in De Hippocratis et Platonis Dogmatibus: balmed specimen from their limited range on the Kuhn's ed., vol. 5, pp. 520-538. Rock of Gibraltar ('where they are held sacred by 29 On many occasions Galen presents animal anatomy the British' in Goss's words) and has been able to as if he were discussing the human body, and, in establish the great accuracy of Galen's descriptions on September 27, 2021 by guest. Protected copyright. particular, On the Use of the Parts is based on the (private communication). structure of the domestic animals (with some 41 French, R. K., 'The origins of the sympathetic simian material). The book is addressed equally to nervous system from Vesalius to Riolan', Med. philosophers and to physicians, and Galen is anxi- Hist., 15(1971), 45-54. 42 445ff. ous throughout to illustrate the virtues of Nature May's translation, pp. as a Creator: the human body in this connection i3 Sisson, S., The Anatomy of the Domestic Animals, is obviously of much greater interest than that of Philadelphia, 1953, pp. 852, 878. animals, and Galen slides easily from one to the 44 De Hippocratis et Platonis Dogmatibus: Kuhn's other without always keeping his readers fully ed., vol. 5. informed. (In contrast, the strictly practical On 45 De Motu Musculorum: Kuhn's ed., vol. 1, p. 1. Anatomical Procedures is expressly about the dis- 46 Kuhn's ed., vol. 1, p. 602. section of apes.) A good example of Galen mis- 47 May's translation of On the Use of Parts, p. 294. his audience is his discussion of the lung: 48 Harris, op. cit., pp. 290ff. leading Use the 'It is not my purpose to speak of the number of 49 May's translation of On the of Parts, pp. lobes in each of the other animals, nor is my dis- 41, 425. 50 course ever concerned with the construction of any Ibid., p. 311. in except perhaps to pro- 51 Ibid., p. 309. other instrument animals, 52 Ibid., p. 320. vide a point of departure for the explanation of it in man. If death does not come to me soon, I Requests for reprints to: R. K. French, PhD, Director, shall one day explain construction in animals too, Univer- dissecting them in detail, just as I am doing for Wellcome Unit for the , man'. (May's translation of On the Use of Parts, sity of Cambridge, Free School Lane, Cambridge.