Rhuthmos

The Introduction of Rhythm in Life Science and Medicine (4th – 3rd century BC) – Part 1

Pascal Michon — 2017-12-14T21:00:00Z

Sommaire

In this chapter, I would like to present the main channels of the introduction of rhythm—under its Platonic guise—in life science and medicine during the end of the 4^th and the 3^rd centuries. I will naturally use the expression “life science” as a handy way to denote studies that were not considered yet as constituting a unified domain. To avoid any misunderstanding, I would like to emphasize also that I won't discuss the various doctrines of ancient philosophers and physicians for their own sake, nor the complex web of influences that can be traced in each one of them. My only interest is to assess how the term rhuthmόs was used in these new domains of knowledge and what novel features could have resulted from these new usages. Before addressing the works of some of the greatest 3^rd century physicians, it is yet necessary for the sake of clarity to recall, at least briefly, a few contributions made during the two previous centuries.

Respiration and Pulse without Rhythm – Hippocratic School (5^th cent. – 4^th cent. BC)

There is no extant evidence that the term rhuthmόs was already used by the Greek physicians of the 5^th century to refer to the respiration (ἀναπνοή – anapnoê) or to the pulse (σφυγμός – sphugmόs). In Hippocrates (ca. 460-ca. 370 BC) the latter term did not denote a natural and regular physiological motion in the body but unnatural motions caused by disease or extreme emotion—e.g. in Prognostics (second half of the 5^th century) and Epidemics (ca. 410 BC). The pulse was not clearly constituted as a medical or scientific object.

The Liddell-Scott-Jones dictionary mentions one occurrence of rhuthmόs in the Hippocratic writings but it clearly has the pre-Platonic meaning of “shape.”

And a small shoe made of lead is to be bound on externally to the bandaging, having the same shape as the Chian [from Chios] slippers had [οἷον αἱ χῖαι κρηπῖδες Ρ῾υθμὸν εἶχον – hoîon aì khîai krêpîdes Rhuthmòn eîkhon]. (Hippocrates, On the Articulations, trans. Charles Darwin Adams)

The same seems to be the case with most Hippocratic physicians in the 4^th and the 3^rd centuries. Diocles of Carystus (ca. 375 BC – ca. 295 BC) lived and worked in Athens, where he wrote what may be the first medical treatise in Attic, not in Ionic as was customary in Greek medical writings [1]. His most important work was in practical medicine, especially diet and nutrition, but he also wrote the first systematic textbook on animal anatomy. The remaining fragments of his works have been recently collected and translated into English by Philip van der Eijk, with a commentary in a separate volume. Apparently, they show nothing specific on pulse nor any use of the term rhuthmόs to denote the pulse (see Index in Philip van der Eijk, 2000).

Praxagoras (ca. 340 BC - ?) was another emblematic figure of the Hippocratic school [2]. Very little is known about his life, except that he was born on the island of Kos in a family of physicians. His grandfather had been one of Hippocrates' students. None of his writings has survived. Most remaining fragments we owe to Galen, Rufus, Athenaios, Pliny, and a few others sources.

Praxagoras studied Aristotle's anatomy. He opposed the view that arteries carried only liquids. Instead, he saw them as tubes, similar to the trachea and bronchi, which carried pneuma, the mystic force of life. Arteries took the breath of life from the lungs to the left side of the heart and through the aorta to the arteries of the body. The veins came from the liver and carried blood, which was created by digested food, to the rest of the body. The combination of blood and pneuma generated heat.

Despite these errors, Praxagoras was apparently the first to direct attention to the importance of arterial pulse in diagnosis. He discovered that pulsation only occurs in the arteries, not in the veins. But, at the same time, he insisted that arteries pulsed by themselves and were independent of the heart (Galen, De pulsuum differentiis, 4.2, 8.702-3). Moreover, according to him, the pulse (σφυγμός – sphugmόs) did not differ essentially but only in magnitude from palpitation (παλμός – palmόs), spasm (σπασμός – spasmόs) and tremor (τρόμος – trόmos). All four motions were forms of πάθη – pathê or involuntary movements of the arteries (Galen, De puls. diff., 4.2, 8.716, see also 4.3, 8.723, and Pseudo-Rufus, Synopsis de pulsibus, 2, ed. Daremberg & Ruelle, 1879, p. 220).

Nothing extant from the Hippocratic writings seems to show any use of the term rhuthmόs to characterize the respiration which is called anapnoê nor the pulse which is always referred to as sphugmόs.

Respiration and Pulse without Rhythm – Plato, Aristotle (4^th cent. BC)

When Plato (428/427-348/347 BC) in the Timaeus (361-347 BC) describes the respiration, which, he believes, is related to the heart beat and digestion, he never uses the term rhuthmόs either to designate its alternating movement (33c, 78e, 79e). He only refers to the pair of words εἰσπνοή – eispnoê – inspiration and its opposite ἐκπνοή – ekpnoê – expiration. The pulse is only vaguely alluded to through “the inward fire attached thereto” that is διαιωρούμενον – diaiôroúmenon – moving to and fro. This fire, which maintains life, dissolves the meats and drinks, divides them into particles and forces them into the veins, “as through pipes,” where they are transported to all parts of the body.

And to this kind of process the Giver of Titles gave, as we say, the names of “inspiration” and “expiration” [ἀναπνοὴν καὶ ἐκπνοὴν – anapnoên kaì ekpnoên]. And the whole of this mechanism and its effects have been created in order to secure nourishment and life for our body, by means of moistening and cooling. For as the respiration [ἀναπνοῆς – anapnoês] goes in and out [εἴσω καὶ ἔξω – eísô kaì éxô] the inward fire attached thereto follows it; and whenever in its constant oscillations [διαιωρούμενον – diaiôroúmenon – moving to and fro] this fire enters in through the belly and lays hold on the meats and drinks, it dissolves them, and dividing them into small particles it disperses them through the outlets by which it passes and draws them off to the veins, like water drawn into channels from a spring; and thus it causes the streams of the veins to flow [τῶν φλεβῶν ποιεῖ ῥεύματα – tôn phlebôn poieî rheúmata] through the body as through a pipe. (Plato, Timaeus, 78e-79a, trans. W.R.M. Lamb)

The heat, which resides inside the body as the living principle, “flows” as an internal “fire font.” The respiration, whether by the lungs or the skin, functions as a cooling system that alternatively brings into the body fresh air and expels the heat in excess out of it. The alternation of inspiration and expiration is like “a wheel that oscillates backwards and forwards [saleuόmenon means causing to rock, making to oscillate; apeirgasménon means to finish off, to complete].”

The originating cause of these processes we must assume to be this. Every living creature has its inward parts round the blood and the veins extremely hot, as it were a fount of fire residing within it [...] Now we must agree that heat, by Nature's law, goes out into its own region to its kindred substance; and inasmuch as there are two outlets, the one out by way of the body, the other by way of the mouth and the nose, whenever the fire rushes in one direction it propels the air round to the other, and the air which is thus propelled round becomes heated by streaming into the fire, whereas the air which passes out becomes cooled. And as the heat changes its situation and the particles about the other outlet become hotter, the hotter body in its turn tends in that direction, and moving towards its own substance propels round the air which is at the former outlet; and thus the air, by continually undergoing and transmitting the same affections, causes inspiration and expiration [ἀναπνοὴν καὶ ἐκπνοὴν – anapnoên kaì ekpnoên] to come about as a result of this double process, as it were a wheel that oscillates backwards and forwards [κύκλον οὕτω σαλευόμενον ἔνθα καὶ ἔνθα ἀπειργασμένον – kúklon houtô saleuόmenon éntha kaì éntha apeirgasménon]. (Plato, Timaeus, 79c-79e, trans. W.R.M. Lamb)

In the Phaedrus (251d) an anguished soul, separated from a youth's beauty, throbs like a pulse in fever. But this use of pulse (σφυγμός – sphugmόs) is still consistent with the older meaning referring primarily to violent motions and pathological symptoms associated with fear or fever (van Staden, 1989, p. 268).

Aristotle (384-322 BC), who seems more familiar than Plato with the Hippocratic Corpus, explicitly rejects Plato's theory of respiration but only on the ground that inspiration, according to him, is not second to expiration but comes first. For the rest, he replicates the view of the heat as living principle and of the respiration as cooling system. In this context, he never uses the term rhuthmόs either.

In Περὶ νεότητος καὶ γήρως, καὶ ζωῆς καὶ θανάτου, καὶ ἀναπνοῆς – Perì neótêtos kaì gêrôs, kaì zôês kaì thanátou, kaì anapnoês – On Youth, Old Age, Life and Death, and Respiration, written around 350 BC, he claims that inspiration and expiration “go on in alternation” or “one after the other”—in that order.

Further, the method of explaining [the respiration] involves a fiction. It is said [by Timaeus] that when the hot air issues from the mouth it pushes the surrounding air, which being carried on enters the very place whence the internal warmth issued, through the interstices of the porous flesh; and this reciprocal replacement is due to the fact that a vacuum cannot exist. But when it has become hot the air passes out again by the same route, and pushes back inwards through the mouth the air that had been discharged in a warm condition. It is said that it is this action which goes on continuously when the breath is taken in and let out expire [ἀναπνέοντάς τε καὶ ἐκπνέοντας – anapnéontas te kaì ekpnéontas]. But according to this way of thinking it will follow that we breathe out before we breathe in. But the opposite is the case, as evidence shows, for though these two functions go on in alternation [γίνεται μὲν γὰρ ἀλλήλοις ταῦτα παρ' ἄλληλα – gínetai mèn gàr allêlois taûta par' állêla – lit. occurs indeed one after the other], yet the last act when life comes to a close is the letting out of the breath, and hence its admission must have been the beginning of the process. (Aristotle, On Respiration, part 11, trans. G. R. T. Ross)

Aristotle, borrowing from the earlier Hippocratic treatise On Regimen (5^th century), compares many times the lungs to double bellows, but their alternation is never qualified as rhythm or rhythmic. The influence of heat forces the lungs to expand, causing inhalation, and this introduction of cold air from outside causes in turn contraction and exhalation.

For when the breath is not let out and the heat accumulates too much then we need to respire, and to respire we must draw in the breath. When hot, people breathe rapidly [δὲ πολλάκις ἀναπνέουσιν – dè pollákis anapnéousin – lit. breathe many times or often], because they must do so in order to cool themselves. (Aristotle, On Respiration, part 10, trans. G. R. T. Ross)

The chest is raised in the manner of a forge-bellows when the breath is drawn in. It is quite reasonable that it should be heat which raises up and that the blood should occupy the hot region. But it collapses and sinks down, like the bellows once more, when the breath is let out. The difference is that in a bellows it is not by the same channel that the air is taken in and let out [κατὰ ταὐτὸν εἰσδέχονταί τε τὸν ἀέρα καὶ πάλιν ἐξιᾶσιν – katà tautòn eisdékhontaí te tòn aéra kaì pálin exiâsin], but in breathing it is. (Aristotle, On Respiration, part 13, trans. G. R. T. Ross)

In similar fashion as the fish move their gills, respiring animals with rapid action [πολλάκις – pollákis – lit. often, many times] raise and let fall [ἄνω καὶ κάτω κινεῖται – ánô kaì kátô kineîtai – lit. move upwards and downwards] the chest according as the breath is admitted or expelled [δεχομένων τὸ πνεῦμα καὶ ἐξιέντων – dekhoménôn tò pneûma kaì exiéntôn – lit. receive and expel the breath]. (Aristotle, On Respiration, part 22, trans. G. R. T. Ross)

The inward passage of the air is called respiration, the outward expiration, and this double movement goes on continuously [Καὶ ἀεὶ δὴ τοῦτο γίνεται συνεχῶς – Kaì aeì dê toûto gínetai sunekhôs] just so long as the animal lives and keeps this organ in continuous motion [καὶ κινῇ τοῦτο τὸ μόριον συνεχῶς – kaì kinêi toûto tò mόrion sunekhôs]; it is for this reason that life is bound up with the passage of the breath outwards and inwards [καὶ διὰ τοῦτο ἐν τῷ ἀναπνεῖν καὶ ἐκπνεῖν ἐστι τὸ ζῆν – kaì dià toûto en tôi anapneîn kaì ekpneîn esti τὸ zên]. (Aristotle, On Respiration, part 27, trans. G. R. T. Ross)

The lungs constitute the primary cooling organ of the heart which embodies the “hot substance” in animals. Respiration, heart pulsations and even palpitations are therefore in some ways connected by the circulation of vital heat, but they are also to be distinguished.

In connection with the heart there are three phenomena, which, though apparently of the same nature, are really not so, namely palpitation, pulsation, and respiration [πήδησις καὶ σφυγμὸς καὶ ἀναπνοή – pêdêsis kaì sphugmòs kaì anapnoê]. (Aristotle, On Respiration, part 26, trans. G. R. T. Ross, my mod.)

Although the distinction between the two vascular systems, the venous and arterial, will not be worked out until the generation after him, Aristotle is apparently the first to depict pulsation as a constant in all blood vessels and to suggest its connection with the heart. In his Historia animalium, he says that “the blood in animals pulsates [σφύζει – sphúzei] in all the blood vessels throughout [the body] at once” (Historia animalium, 3.19.521a, comments and quote by van Staden, 1989, p. 269).

Contrary to the Hippocratic physicians, who see the pulse as an unnatural motion caused by disease or emotion, Aristotle considers it a natural and continuous physiological motion. According to him, the heart produces the blood from the fluid supplied by the food. Then, under the influence of heat, the blood volume expands and, as in the throbbing of an abscess or, more precisely, in boiling water, the surplus is more or less regularly discharged. But again, he makes no mention of rhythm in these passages.

[The pulsation accompanying] the heart [σφύξις τῆς καρδίας – sphúxis tês kardías], which, as can be seen, goes on continuously, is similar to [the throbbing of] abscesses [ὁμοία φύμασίν ἐστιν – homoía phúmasín estin]. That, however, is accompanied by pain, because the change produced in the blood is unnatural, and it goes on until the matter formed by concoction is discharged. There is a similarity between this phenomenon and that of boiling; for boiling is due to the volatilization of fluid by heat and the expansion consequent on increase of bulk. But in an abscess, if there is no evaporation through the walls, the process terminates in suppuration due to the thickening of the liquid, while in boiling it ends in the escape of the fluid out of the containing vessel. (Aristotle, On Respiration, 20.479b-480a, trans. G. R. T. Ross, my mod.)

Like his predecessors, Aristotle thus refers to the pulse with the terms sphúxis, sphugmόs or sphúzein. But only the blood vessels (phlébes) pulsate (sphúzousin), due to their “connection with the heart.”

In the heart [Ἐν δὲ τῇ καρδίᾳ – En dè têi kardíai] the beating is produced [ποιεῖ σφυγμόν – poieî sphugmόn] by the heat expanding the fluid, of which the food furnishes a constant supply. It occurs when the fluid rises to the outer wall of the heart, and it goes on continuously; for there is a constant flow of the fluid that goes to constitute the blood, it being in the heart that the blood receives its primary elaboration. That this is so we can perceive in the initial stages of generation, for the heart can be seen to contain blood before the veins become distinct. This explains why pulsation [σφύζει – sphúzei] in youth exceeds that in older people, for in the young the formation of vapor is more abundant. [All the blood vessels pulsate] [Καὶ σφύζουσιν αἱ φλέβες πᾶσαι – Kaì sphúzousin hai phlébes pâsai], and do so simultaneously with each other, owing to their connection with the heart. [Since the heart is always in motion [Κινεῖ δ' ἀεί ὥστε – Kineî d'aeí hôste], so are the [blood vessels], and their motion keeps running continuously and simultaneously as long as the heart moves [ὅτε κινεῖ – hόte kineî]] [...] [Pulsation, then, is the evaporation [volatilization; pneumatization] of the heated moisture.] (Aristotle, On Respiration, 20.479b-480a, trans. G. R. T. Ross, my mod.)

Both heart-beat and pulse are, in Aristotle's view, normal and constant bodily functions, and they both result from the pneumatization or vaporization of food derivates which are in liquid form. However, as in Hippocratic writings and in Plato, there is no sign in Aristotle of any use of ῥυθμός – rhuthmόs – rhythm or ῥυθμοειδής – rhuthmoeidês – rhythmical to refer to them.

Respiration with Rhythm – Peripatetic School's Problems (3^rd c. BC)

The Προβλήματα – Problêmata – Problems, which is a pseudo-Aristotelian collection of questions and answers gradually assembled by members of the peripatetic school since possibly the end of the 4^th century and more probably the 3^rd century, is one of the first texts where the term rhuthmόs is used to refer to respiration. However, the gap between the Aristotelian sophisticated rhythmic analyses developed in Rhetoric and Poetics and the gross definitions given in passing in this collection suggests that the issue of rhythm was not any more considered as central in the school and that the few uses that we find in it are borrowed from other sources, most probably medical writings.

While endorsing, as we shall see, the Platonic definition of rhythm as “order of movement,” The Problems demonstrate a typical Aristotelian interest for empirical observation. In Book 19, the Platonic question of the relation between musical rhythms, melodies and ἦθος – êthos – disposition, character, is addressed as a fact granted by observation. But the Aristotelian author (borrowing from Aristotle, cf. Politics, 8.1340a) divides and reverses the issue: he asks why music but not color nor smell nor flavor, instead of influencing one's character, can represent what we call psychological moods or what the Greeks called ethical character? As melody, rhythm is a movement in sound that has a “likeness” to ethical character. It is not clear whether rhythm is here only a movement or if it is presupposed to be, as we shall see in Book 5, a more or less regular repetition of alternate times, but the association with melody suggests that it is the case.

Why does what is heard, alone of perceptible objects, possess ethical character [ἦθος ἔχει – êthos ékhei – lit. bears, carries character]? Indeed, even if a melody is without words, it nonetheless possesses ethical character [ὅμως ἔχει ἦθος – homôs ékhei êthos]; but neither color nor smell nor flavor possess it. Is it because [what is heard] alone possesses movement, though not that which the sound moves in us? [...] This movement has a likeness [to ethical character] both in the rhythms and in the arrangement of high and low notes, not in their mixture. But consonance has no ethical character. (Problems, Book 19, 919b, trans. Robert Mayhew)

Why do rhythms and melodies, which are sound, resemble ethical character, while flavors do not, nor colors and odors? Is it because they are movements, as actions too are? Now activity is ethical and produces ethical character, but flavors and colors do not act in this way. (Problems, Book 19, 920a, trans. Robert Mayhew)

In another occurrence, the author claims that “we enjoy rhythm because it has a recognizable and orderly number and moves us in an orderly fashion.” Yet, according to Aristotle's more earthly orientation, eurhythmy is no longer imitation of the perfect heavenly movements but results from moving according to human nature, i.e. regularly and without excess. “Exercising and drinking and eating in an orderly fashion” helps us to “preserve and improve our nature and power,” whereas disorderly behavior “ruins and deranges it.” Rhythmicity, defined on a Platonic basis, becomes medically beneficial regularity.

Why does everyone enjoy rhythm and melody [ῥυθμῷ καὶ μέλει – rhuthmôi kaì mélei] and in general all concords [συμφωνίαις – sumphôníais]? Is it because we naturally enjoy natural movements? Now a sign of this is that children enjoy these straightaway from birth. And we enjoy different types of melody because of habituation. But we enjoy [rhythms] [ῥυθμῷ – rhuthmôi] because [they have] a recognizable and orderly number and [move] us in an orderly fashion; for orderly movement is naturally more akin to us than disorderly, and so is more natural. And here is an indication of this: by exercising and drinking and eating in an orderly fashion we preserve and improve our nature and power, but in a disorderly fashion we ruin and derange it: for diseases are movements of the order of the body not in accordance with nature. But we enjoy concord, because it is a mix of opposites standing in proportion to one another. Therefore proportion is an order that is naturally pleasant. (Problems, Book 19, 920b-921a, trans. Robert Mayhew, my mod.)

Whereas the two previous series of occurrences were still taking part in quite traditional musical and ethical discussions, adding a more empiricist view to it, the last occurrence of the term rhuthmόs in the Problems is more innovative. Under the influence of Plato and Aristotle, the term rhythm is still defined as what is “measured by definite [or divided] movement.” But it is used to denote the regular respiration of runners when they jog without excess: “As soon as they begin to run they breathe, and as their breathing is coming regularly because it is measured by regular movement, it produces a rhythm.” When someone is sitting or walking slowly, the rhythm of his breath is difficult to observe; but it is the same if someone runs to fast. Rhythm here clearly means a perceptible regular repetition of alternate times.

Why do those who are not running under great strain breathe rhythmically [έν τῷ ῥυθμῷ ἀναπνέουσιν – én tôi rhuthmôi anapnéousin]? Is it because all rhythm [πᾶς ῥυθμὸς – pâs rhuthmòs] is measured by definite movement [ὡρισμένῃ μετρεῖται κινήσει – hôrisménêi metreîtai kinêsei – lit. by divided movement], and the kind of movement that runners make is regular? So as soon as they begin to run they breathe, and as their breathing is coming regularly because it is measured by regular movement [ἴσῃ κινήσει μετρεῖσται – ísêi kinêsei metreîstai], it produces a rhythm [ῥυθμὸν ποιεῖν – rhuthmòn poieîn]. Or is it because all breathing without qualification is regular in those who employ it naturally and do not hold their breath? So in those sitting or walking, as the movement of the body is moderate, the rhythm [ὁ ῥυθμὸς – ho rhuthmòs] is not obvious; while in those running intensely, as our perception cannot follow the movement, we are unable to observe the rhythm of the breathing. But in the one running moderately, the movement, making the measure of breathing perceptible, reveals its rhythm [τὸν ῥυθμὸν – tòn rhuthmòn]. (Problems, Book 5, 882b, trans. Robert Mayhew)

Although rhythm does not play a great role in The Problems, this collection constitutes an important token of the spreading and transformation of the concept during the late 4^th and 3^th centuries BC, even though we are not sure of the beginning of their assembly. It is one of the first times, at least to my knowledge, that rhythm is used outside dance, music and poetry and translated to another field, sc. physiology, to refer to the respiration.

Pulse with Rhythm – Peripatetic Anonymus' On Breath (first half or mid-3^rd cent. BC)

A similar conceptual extension, this time concerning the pulse, seems to take place in another Peripatetic text of the same period: Περὶ πνεύματος – Perì pneúmatos – On Breath often referred to by its Latin name De spiritu. In modern times, its ancient attribution to Aristotle has been virtually unanimously rejected [3], and most or all of it has been acknowledged to be an early work of the Peripatetic school, possibly connected with Theophrastus (ca. 371 – ca. 287 BC) or Strato of Lampsacus (ca. 335 – ca. 269 BC) [4].

I won't discuss the doctrines evoked by the treatise for their own sake: the method of nutrition of the vital breath (πνεῦμα – pneûma)—a concept borrowed from Aristotle—either by the air inspired by the lungs or internally by the blood. I won't neither discuss the various influences that can be traced in it: specialists do agree on the Aristotelian background of the author but they diverge on the exact interpretation of his differences with Aristotle, particularly whether the author was deeply influenced by Erasistratus (ca. 304 – ca. 250 BC) (Jaeger), or had loose connection with his teaching (Gregoric & Lewis), or clearly rejected it (Federspiel). Once again, my only interest is to assess how this mid-3^rd century member of the Peripatetic school made use of the term rhuthmόs, whatever his specific physiological beliefs were.

The author of the De spiritu sometimes uses rhuthmόs and its verbal extension rhuthmízousai in a very traditional way. These words then mean respectively “shape” and “to give shape.”

For different results are achieved by fire in the work of the goldsmith, the coppersmith, the carpenter, and the cook—though, perhaps, it is truer to say that the arts themselves achieve these different results, for that by using fire as an instrument they soften, liquefy, and desiccate substances, and some they [shape] [ἔνια δὲ καὶ ῥυθμίζουσαι – énia dè kaì rhuthmízousai]. [...] while the crafts use the fire merely as an instrument, nature uses it as a material as well. Certainly no difficulty is involved in this; but rather it is remarkable that nature, who employs the instrument, is herself an intelligent agent, who will assign to objects their proper [shape] [καὶ τὸν ῥυθμὸν – kaì tòn rhuthmòn] together with the visible effects of her action : for this is no longer a function either of fire or of breath. (Anonymus, De spiritu, 485a-485b, trans. J.F. Dobson, my mod.)

But the author also employs rhuthmόs in a more innovative way to refer to the pulse (sphugmόs)—which is one more piece of evidence that proves that the text cannot be attributed to Aristotle and must have been written by one of his successors in the Peripatetic School [5].

He starts from Aristotle's theories: contrary to early Hippocratics' view, the pulse is a natural physiological motion. However, it is not only a side effect of the internal heat, as Aristotle claimed; it constitutes a primary “activity” or function of the heart (ἐνέργεια – enérgeia).

Respiration begins when the young is separated from the mother; the reception of nutriment, and nutrition, both while the embryo is forming and after it is formed; but the pulsation [ὁ δὲ σφυγμὸς – ho dè sphugmόs] at the earliest stage [ἐν τῇ ἀρχῇ – en têi arkhêi], as soon as the heart begins to form, as is evident in the case of eggs. So the pulse comes first [ὥστε αὕτη πρώτη – hôste haútê prôtê], and resembles an activity [καὶ ἔοικεν ἐνεργείᾳ τινὶ – kaì éoiken energeíai tinì] and not an interception of the breath, unless that also can conduce towards its activity [πρὸς τὴν ἐνέργειαν – pròs tên enérgeian]. (Anonymus, De spiritu, 483a, trans. J.F. Dobson)

Moreover, the pulse, which is to be differentiated “from the other motions,” i.e. respiration and maybe palpitation, “extends to the other parts” of the body. This differentiation is motivated by the initial question of the treatise: does the blood, and not the respiration, bring nutrition to the pneûma. Simultaneously, the author still refers to Aristotle's doctrine of internal heat and “bubbling” blood from the heart.

The pulse [σφυγμὸς – sphugmόs] is something peculiar and distinct from the other motions and in some respects may be seen to be contingent, assuming that when there is an excess of warmth in a fluid, that fluid which is evaporated must set up a pulsation owing to the air being intercepted in the interior, and pulsation must arise in the originating part and in the earliest stage, since it is inborn in the earliest parts. For it arises firstly and in the greatest degree in the heart, and thence extends to the other parts. Perhaps this must be an inseparable consequence of the essential nature underlying the living creature, which is manifested when the creature is in a condition of activity. (Anonymus, De spiritu, 482b, trans. J.F. Dobson)

Usually the pulse “remains the same and unchanged” but it may become “irregular and spasmodic owing to certain bodily affections and in consequence of fear, hope, and anguish affecting the soul.” Whereas Aristotle used two different terms—pêdêsis for the heart's rapid motion in the emotional state of fear and sphugmόs for the constant motion of the heart and the veins—the De spiritu innovates, in fact as Herophilus a few years before, by employing the same term sphugmόs for both kinds of motion.

That the pulse [ὁ σφυγμός – ho σφυγμός] has no connection with the respiration [ἀναπνοὴν – anapnoên] is shown by the following indication—whether one breathes [483a] quickly or regularly [ὁμαλὸν – homalòn], violently or gently, the pulse [σφυγμὸς – sphugmόs] remains the same and unchanged [ὅμοιος καὶ ὁ αὐτός – hόmoios kaì ho autόs], but it becomes irregular and spasmodic owing to certain bodily affections and in consequence of fear, hope, and anguish affecting the soul. (Anonymus, De spiritu, 482b-483a, trans. J.F. Dobson)

This series of arguments leads the author of De spiritu to finally consider whether, contrary to Aristotle who thought that only the veins pulsate, also arteries do, and, if this is the case, whether they pulse “with the same rhythm and regularity”—most likely meaning: as the heart and maybe the veins. Borrowing from Erasistratus, he immediately adds that it “does not appear to be so in the case of parts widely separated,” which implies that some arteries and veins do not pulsate at the same time, due possibly to their distance to the heart since the author rejects the idea of autonomous motions.

Next we ought to consider whether the pulse occurs also in the arteries and with the same rhythm and regularity [as in the heart] [κἂν ὁ αὐτὸς ὢν ἐν ῥυθμῷ καὶ ὁμαλὸς ᾖ – kàn ho autòs ôn en rhuthmôi kaì homalòs êi]. This does not appear to be so in the case of parts widely separated. (Anonymus, De spiritu, 483a, trans. J.F. Dobson)

Gregoric and Lewis recently proposed a new translation of this passage: “We must examine whether the artēriai also pulsate and whether, having the same rhythm [as the pulse in the heart and hē artēria], [the pulse in the artēriai] is also even.” They think that the term ὁμαλὸς – homalòs – even refers to “the question of whether the heart and the artēriai expand and contract simultaneously or alternately.”

The evenness may, perhaps, refer to the question of whether the heart and the artēriai expand and contract simultaneously or alternately (ἔμπαλιν σφύζειν): while Erasistratus believed that the artēriai expand when the heart contracts (because it pushes the pneuma into the artēriai when it contracts), Herophilus and Galen claimed that the arteries expand together with the heart's expansion. (Gregoric & Lewis, 2015, p. 165, n. 28)

This is an interesting point but it presupposes that rhuthmόs might already mean “regular beat,” and that consequently the question would concern only the synchronicity of the arterial regular beat with that of the heart. But one may doubt that the term has here such a definite and “modern” meaning. As in the Problems, it already clearly involves some repetition of alternate times, but it does not imply their strict regularity. And that is why, in my opinion, the author feels compelled to complete his characterization of the pulse with the term ὁμαλὸς – homalòs, that should be therefore translated as “regular or even by themselves” and not “synchronous or even with the heart beat.”

As a matter of fact, ἐν ῥυθμῷ – en rhuthmôi—an expression, it is worth noticing, that was already used in the Problems to refer to respiration—was an expression often used to refer to dance or to military marching. It meant “in time” and described an alternate motion that was reproduced simultaneously by a group of dancers or soldiers. The Liddell-Scott-Jones Dictionary reads “ἐν ῥυθμῷ – en rhuthmôi = in time, of dancing, marching, etc.” It quotes Plato's Laws (Lg.670 b) : “βαίνειν ἐν ῥ. – baínein en rhuthmôi = being drilled”; and Thucydides (Th.5.7): “μετὰ ῥυθμοῦ βαίνοντες – metà rhuthmoû baínontes” = stepping in time.

En rhuthmôi is then clearly used in De spiritu as a metaphor comparing the motions of the various arteries with those of dancers or soldiers. In this sense, it seems lagging a little behind the progress of medicine in the first half of the 3^rd century. It has not yet the sense of regularity that has already come to the foreground with Herophilus. This seems to prove that in the Peripatetic school the first extensions of the concept of rhuthmόs out of poetry, music and dance theory towards life science have not been the result of an autonomous doctrinal change but most probably reflect the influence of the Alexandrian school of medicine

Next chapter

[1] On Diocles of Carystus see Philip van der Eijk, 2000.

[2] For the next paragraphs on Praxagoras I used mainly Paulys Realencyclopädie der classischen Altertumswissenschaft, Band XXII, 2 (1954), sp. 1735-1743. See also Lewis, Orly. 2017 and van Staden, 1989, p. 270.

[3] Although re-attribution to Aristotle has recently been attempted by Bos and Ferwerda (2008).

[4] In his classic 1913 study, Werner Jaeger situated the treatise in the middle of the third century BC. More recent scholarship tends “to favor a slightly earlier dating” (Gregoric & Lewis, 2015, p. 166). “The author of the On Breath remains unknown. All that can be affirmed with certainty is that it is not a physician, but a Peripatetician contemporary with Eratistrate or slightly posterior, i.e. from the first half or the middle of the 3^rd century BC. The conciseness and obscurity of his work suggest that he dealt with subjects already known by readers of his time; from this it can be inferred that the main theses of the new medicine were known and discussed in the Peripatetic school in the 3^rd century.” (Federspiel & Guillaumin, 2017, my trans.)

[5] Pavel Gregoric and Orly Lewis have recently reviewed all pieces of evidence that speak against an attribution of the treatise to Aristotle. They refer to the pulse but do not discuss specifically the use of rhuthmόs (Gregoric & Lewis, 2015).

The Introduction of Rhythm in Life Science and Medicine (4th – 3rd century BC) — Part 2

Pascal Michon — 2017-12-14T20:00:00Z

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Rhythm as Characteristic of Artery Pulse – Herophilus (ca. 325-255 BC)

Born in Chalcedon-Bithynia a few years after Aristole's death (322 BC), Herophilus moved at a fairly young age to Alexandria to begin his schooling. He was one of Praxagoras' pupils, yet we do not know where he received his teaching. He seems to have spent most of his life in Egypt. He wrote at least eight books, unfortunately none of them remains [1].

Through Praxagoras, he was familiar with Aristotle's anatomy and physiology; he also knew that pulsation only occurs in the arteries, not in the veins; that the pulse can be perceived in us from birth to death as an activity or function; and he was accustomed to pay attention to it for diagnosis. However, he surpassed both of his predecessors because he was one of the first scientists to perform systematic dissections of human cadavers.

Concerning the pulse, he opposed his master's opinion by clearly distinguishing between pulse and palpitation: “διορίζοντα σφυμòν παλμοῦ – diorìzonta sphugmòn palmoû” (Galen, De pulsuum differentiis, 4.2, 8.716, see also 4.3, 8.723 and Rufius Ephesius, Synopsis de pulsibus, 2, in von Staden, 1989, p. 327) [2], “putting a definitive end, as Littré put it, to confusion in terms and things” (Littré, Hippocrate, 1842, chap. 9). Concurrently, he seems to have initiated the distinction between the two phases or parts of the pulse: the διαστολή – diastolê – dilation when the artery moves outward towards the physician's touch; and the συστολή – sustolê – contraction when it moves inward again, away from the touch [3].

He also opposed Praxagoras' view that the arteries pulsate by themselves and maintained that they pulse from two sources: from some connection to the heart and from a faculty flowing to them through their tunic (Galen, De puls. diff., 4.2, 8.702-703). This was, according to him, “the reason why all of the arteries are observed to dilate at one and the same time and to contract [simultaneously], preserving for the heart the same fixed time for both motions.” (Galen, De puls. diff., 4.6, 8.733, trans. Heinrich von Staden). However, this simultaneity did not mean that the pulse was, in his view, related to the action of the heart as a pump and that it was provoked by the dilation of the arteries under the successive blood waves. The blood circulation and the central role of the heart in it were indeed discovered only in the 17^th century by Harvey.

His general views on the human body and the role of pulse are excellently recapitulated by Heinrich von Staden.

Herophilos seems to have believed that the body is a material continuum that harbors no void, and that invisible, innate capacities or faculties control and regulate all bodily functions, often by attracting or pulling various forms of matter—liquids, solids, air—through ducts and other spaces in the body toward their appropriate destinations. These innate faculties are thoroughly secularized; no claim of divine design or divine force is made for them. Thus an invisible, innate faculty (“vital dynamis”?), extending simultaneous dilatation and contraction of the heart and of all arteries. This dynamis thereby pulls or “attracts” a mixture of blood and pneuma (the latter ultimately derived from respiration) from the heart through the entire body via the arterial system. Blood (without pneuma) apparently is similarly moved through the veins, while pneuma—by means of which at least some sensory and voluntary motor activity is conducted—is moved through the nerve ducts. (Von Staden, 1996, p. 87)

Since none of his writings remains, we have no direct evidence that he ever used the term rhuthmόs to refer to the pulse in his famous Περì σφυγμῶν – Perì sphugmôn – On pulses. But, thanks to quite abundant later sources (Pliny, Marcellinus, Pseudo-Rufus, Galen, and others), we are able to assert with enough certainty that he did.

Since the end of the 19^th century, there has been a swinging debate concerning the origin of Herophilus' definition of pulse rhythm. Wellmann (1895) long ago suggested that Herophilus adopted his terminology and theory of rhythm from Aristoxenus of Tarentum. This was also much later Jackie Pigeaud's view (1978, p. 262). But in his influential book on Herophilus, Heinrich von Staden strongly doubted that Aristoxenus influenced Herophilus. He noticed that “none of the numerous ancient sources which acknowledge Herophilus' debt to musical theory or metrics characterize it as a debt to Aristoxenus,” and attributed implicitly his particular use of a limited number of metric patterns to his larger humanist knowledge and the rest of his rhythm theory to his own ingeniousness (1989, p. 278-279). Yet, in his 1996 article, he seemed to change his mind and considered Aristoxenus' influence “possible” (p. 89). Quite recently, Marquis Berrey returned to Wellmann's and Pigeaud's opinion and discussed again the main pieces of evidence that may prove Aristoxenus' influence on Herophilus (2011, p. 60 sq.). I will try to show that Wellmann, Pigeaud and Berrey are most probably correct and that this insight tells us a lot about one of the most important channels through which the Platonic-Aristotelian concept of rhuthmós began to spread over the Greek culture during the 3^rd century BC.

Galen recalls that Herophilus borrowed concepts from “musicians” (mousikoì): he compared the dilation (diastolê) with a musical up-beat (ársis), the contraction (sustolê) with a down-beat (thésis), and the “defined sequences of time-units” they form (hôrisménas khrónôn táxeis – lit. definite or regular order of times) with what the musicians called “rhythm.” In other words, a rhythm amounted to a sequence of dilations and contractions, i.e. of ársis and thésis, characterized by a specific “proportion” between the duration of the former and that of the latter. As we can see, this was a direct and faithful application of the metric Platonic-Aristotelian paradigm.

For, just as musicians [οἱ μουσικοὶ – hoi mousikoì] establish rhythms according to certain defined sequences or time-units [ὡρισμένας χρόνων τάξεις – hôrisménas khrónôn táxeis], comparing up-beat and down-beat with each other [ἀλλήλαις ἄρσιν καὶ θέσιν – allêlais ársin kaì thésin], so too Herophilus supposes that the dilation [διαστολή – diastolê] is analogous to the up-beat [ἄρσει – ársei], while the contraction [of the artery] [τὴν συστολὴν τῆς ἀρτηρίας – tên sustolên tês artêrías] is analogous to the down-beat [θέσει – thései]. (Galen, Synopsis librorum suorum de pulsibus, 12, 9.464, trans. Heinrich von Staden, my mod.)

Let us first note a point that could seem marginal but that will not be without significance, as we shall see when we look into Galen's contribution. According to von Staden, Herophilus characterized the dilated state of the artery as its “natural condition” and the contracting movement as its “activity,” but Galen attributed to him two divergent—and inconsistent—views on this question: sometimes Herophilus considered both the dilation and the contraction an activity or energeia of the artery, but at other times, most often as a matter of fact, only the contraction (von Staden, 1989, p. 272). But, more recently, Berrey has argued that, when he constructs a normative pulse rhythm for each age-group, as we shall see immediately, Herophilus actually makes each cycle start from the dilation of the artery (Berrey, 2011, p. 56). Given the conflicting evidence available to us, it is difficult to decide which option is correct but there is an argument that has not been used yet—without though being decisive: Berrey's view could be more consistent with the choice of ársis and thésis for contraction and dilation noticed by Galen, since in dance and music they refer respectively to the raising and lowering of the feet or the hands and the former necessarily precedes the latter. As Bacchius noticed: “What do we mean by ársis? When our foot is in the air, when we are about to take a step. And by thésis? When it is on the ground.” (Bacchius, Isagoge 98 in Musici Scriptores Graeci, quoted by Pearson, 1990, p. xxiv).

We should also note that Herophilus does not consider pauses or rests to be part of the pulse rhythm. The rhythm is, for him, an organized but continuous series of up-beats and down-beats, with no intervals.

As most musical theory up to the time of Herophilus views up-beat and down-beat as contiguous in time, and hence recognizes no pause between them, so Herophilus—unlike later writers on music and pulse-lore—regards the contracting and dilating motions of the artery as immediately adjacent in time and hence finds no need to elaborate on the intervals of inactivity between contraction and dilation. (von Staden, 1989, p. 277)

Based on the evidence gathered so far, Herophilus' innovation could seem to consist in a mere displacement of concepts from music and poetry theory into medicine. But it is actually more than that. Herophilus further elaborates the common concept of rhythm to adapt it to his needs. This is what we see in a large fragment from his treatise On pulses, quoted in Galen's On differentiating between Pulses.

In this fragment, Herophilus proposes to characterize the pulse by four or five ways to differ (διαφέρειν – diaphérein) i.e. differences, characteristics, or aspects.

When he introduces the subject [Herophilus] says this—for I will write down the entire passage [...] “In general pulse seems to differ from pulse in amount [volume?], size, speed, vehemence [strength], and rhythm [πλήθει, μεγέθει, τάχει, σφοδρότητι, ῥυθμῷ – plêthei, megéthei, tákhei, sphodrótêti, rhuthmôi]. From their differences in these respects pulse at times appears proper and [at times] not proper [οἰκεῖος καὶ οὐκ οἰκεῖος – oikeîos kaì ouk oikeîos – lit. proper to a thing, fitting to their true nature, suitable and not]. One pulse seems to differ and be recognized generally as different from another, as was said, in rhythm, size, speed, vehemence [ῥυθμῷ, μεγέθει, τάχει, σφοδρότητι – rhuthmôi, megéthei, tákhei, sphodrótêti]. [But if, in the same rhythm [ἐν τῷ αὐτῷ ῥυθμῷ – en tôi autôi rhuthmôi], one pulse seems to differ from another, then [it is] in speed, size, and vehemence.]” (Galen, De dignoscendis pulsibus, 4.3, 8.959-60, trans. Marquis Berrey, my mod.)

Two remarks: rhythm (ῥυθμός – rhuthmós) is here contrasted first with four then three other concepts; furthermore, it comes either last or first in the list, as if it had a particular status in the series.

Three of these differentiae are clear enough. The “size – μέγεθος – mégethos” of the pulse means how much the artery moves outward to the physician; the “speed – τάχος – tákhos,” how quickly; the “vehemence – σφοδρότης – sphodrótês,” with how much strength. Size, speed, and strength are clearly three quantitative criteria based on the observation of the dilation, whereas rhythm denotes the qualitative organization of a full cycle encompassing dilation and contraction. Let us notice that contrarily to its rhetoric or poetic counterparts, the pulse rhythm includes no aspect of strength. Rhythm does not perform any action, it is a pure sign, a σημεῖον – sêmeîon.

By contrast, there is a bit of obscurity in the relation of “rhythm” with the fifth differentia: “amount / volume [4] – πλῆθος – plêthos.” Von Staden wonders if, since no other text confirms that Herophilus used “volume” to describe or classify any pulse, it might be “a later interpolation” (von Staden, 1989, p. 274). If it is not, it is unclear whether the disappearance of this differentia in the second sentence of the definition given by Herophilus meant that, in his view, it was related in some way with one of the other differentiae and that it would have been therefore superfluous or redundant to mention it or, more simply, that it was of a lesser importance.

The problem did not escape Galen who concluded, since Herophilus mentioned plêthos only one time in his book, that the fifth differentia was actually for him secondary, even if he took it plainly into account in his practice.

What more reliable witness to Herophilus' view do you wish to get than Herophilus? “One pulse appears,” he says, “to differ from another, in rhythm, size, speed, vehemence, as was said.” If indeed the expression “in [amount]” [πλήθει – plêthei] actually signifies some difference between pulses, why, then, did he omit it here [in the second enumeration] when he resumed his argument, not simply or lazily, but with the addition “as was said”? And why does he say that pulses in the same rhythm [ἐν ταὐτῷ ῥυθμῷ – en tautôi rhuthmôi] differ in speed, size, and vehemence? [...] And what's more, while he appended these very words in just about every case, he nowhere added “in [amount]” [τὸ πλήθει – tò plêthei]. Rather, only in Book 1, not in all his works [did he add it], although he would not have omitted it if indeed it were a name of a difference between pulses. (Galen, De dign. puls., 4.2, 8.959-960, trans. Heinrich van Staden, my mod.)

Berrey suggests that plêthos may have had “some connection to frequency, which Herophilus measured with a water clock”—that will be discussed below—precisely through the flow of a variable “amount” or “volume” of water (Berrey, 2011, p. 56). An interesting clue in favor of this hypothesis is another passage where Galen comments the controversy among later physicians to account for Herophilus' use of a fifth differentia that was already unclear to the Ancients. According to him, “πλήθει – plêthei” would not mean “fullness” as many thought it did, but “frequency – πυκνότης – puknótês.” If it was not among the main differences that supported the pulse classification in four species, it was often mentioned by Herophilus and used in his clinical practice.

I shall start from the passage they put forward, which is recorded in Book 1 of Herophilus' On Pulses. This is also the only passage they seem to have read. It runs as follows: “In general, then, pulse is thought to differ from pulse in [amount] [πλήθει – plêthei], in size [μεγέθει – megéthei], in speed [τάχει – táxei], in vehemence [σφοδρότητι – sphodrótêti], and in rhythm [ῥυθμῷ – rhuthmôi].” This passage they put forward, asking what “[amount]” [πλῆθος – plêthos] is, just as if we would not recognize what kind of thing he signifies with “[in amount]” [πλήθει – plêthei] and as if “fullness” [πληρότητος – plêrótêtos] were necessarily what it means. I then answer—cleverly, I think: for I say the expression “[in amount]” [πλήθει – plêthei] signifies “[in frequency]” [πυκνότητα – puknótêta]. [...] So, since the difference in “fullness” neither reached the point of being discerned, as was shown, nor is mentioned elsewhere by Herophilus, whereas the difference in frequency [πυκνότητα – puknótêta] is conceded by all, and Herophilus is found to record it ten thousands of times, it would be more reasonable to think that “frequency” was meant rather than “fullness.” (Galen, De dign. puls., 4.2, 8.956-958, trans. Heinrich van Staden, my mod.)

We know through other sources that Galen is probably right. Marcellinus (late 1^st – early 2^nd c. AD) provides a precious insight in the clinical use of the pulse frequency, associated with strength and size, by Herophilus as means for measuring fever.

Herophilus declared that a patient had fever whenever the pulse became more frequent [πυκνότερος – puknóteros], larger, and more vehement with much internal heat. If therefore [the pulse] should lessen its vehemence and size, the fever is in remission. He says that the frequency [πυκνότητα τῶν σφυγμῶν – puknótêta tôn sphugmôn] of the pulse becomes primary when fevers begin and remains so until their final resolution. (Marcellinus, De pulsibus, 11, ed. Schöne p. 463, trans. Marquis Berrey)

Moreover, as we will see below, he used frequency to differentiate between pulses of different ages. Nevertheless, it seems that Herophilus paid more attention to speed than to frequency. Von Staden notices that “speed was actively used” by Herophilus “and not ‘frequency'” and that may explain why he did not mention it in his second list of differences.

Whatever the exact relationship between “speed” and “frequency” in Herophilus' pulse-lore might be, it is clear from more than one ancient text that “speed”—and not “frequency”—was actively used by Herophilus to define certain kinds of pulse, i.e. that he did not merely develop “speed” as a hypothetical differentia which in practice was abandoned in favor of “frequency.” (von Staden, 1989, p. 284)

Let us recapitulate. Since plêthos most probably meant “frequency,” its disappearance in Herophilus' second list may well show that it was simply, in his view, another quantitative difference that could supplement the measure of the dilation but that had no direct connection with rhythm, that remained a larger concept encompassing the full cycle of the pulse. But it could also indicate that it was redundant with some other difference—why not rhythm? So we will have to come back to this point below.

Rhythm as Characteristic of Life Stages – Herophilus

So far we have witnessed the emergence, supported by a common metrical knowledge, of the metric Platonic paradigm in a remote area of the medical knowledge. We will see now how, by using more sophisticated concepts borrowed from Aristoxenus, it became central, providing the support for a very long-lasting view of the living. Metric rhythm, which was considered at first only as one of the aspects of the pulse became an essential medical and scientific category—laying the ground for ulterior equating of pulse, respiration and rhythm.

This transformation already shines through, despite its brevity and allusive aspect, in a passage of Pliny's Natural History (23-79 AD), where he reports that “the pulsation of the arteries” was compared by Herophilus to “certain measures and metrical laws, depending on the age of the patient.”

The pulsation of the arteries is more especially perceptible at the end of the limbs; and afford indications of nearly every disease, being either stationary, quickened, or retarded [stabilis aut citatus aut tardus], conformably to certain measures and metrical laws, which depend on the age of the patient [in modulos certos legesque metricas per aetates], and which have been described with remarkable skill by Herophilus, who has been looked upon as a prophet of medicine [with wondrous skill]. (Pliny, Natural History, 11.89.219, trans. John Bostock & H.T. Riley, my mod.)

This point becomes clearer in later more articulated sources which show that Herophilus relates specific pulses to different age-groups, using to that effect Aristoxenus' theory of rhythm, without yet replicating it slavishly.

We remember that the latter started from a primary time-length (πρῶτος χρόνος – prôtos khrόnos), whose nature depended on the rhythmizable matter (ῥυθμιζόμενον – rhuthmizόmenon) which was to be considered (poetry, dance, music), and then constructed the rhythm as an arithmetically organized set of primary time-lengths. He insisted though on the necessity to determine this primary time-length through perception (see chap. 3). Likewise, even if he does not make use exactly of the same words, Herophilus defines the movements of heart and arteries as the “rhythmizable” peculiar to medicine; the “primary time-length” as the interval of time in which the artery of a newborn would dilate; and the pulse rhythm as a “set of primary time-lengths” endowed with variable arithmetic qualities.

Naturally, this does not mean sheer imitation. The Synopsis de pulsibus – Synopsis on Pulse by Pseudo-Rufus of Ephesus (2^nd c. AD) [5] gives a fairly detailed account that shows what he owes to Aristoxenus and what he contributes on his own.

As Aristoxenus, Herophilus proceeds from the bottom up, from the elements to the whole. He starts by defining, based on the pulse of the newborn children, a “primary time-length,” which he calls “álogon – irrational,” or more clearly for us “á-logon – without definable ratios,” i.e. literally without rhythm, just like a point in geometry is both elementary unit of space and without any extension. “It is similar in size, he says, to the prick of a needle.”

Hence, whereas Aristoxenus insisted that the primary time-length be observable, it is qualified by Herophilus as “not distinct” in the newborns and seems thus to be determined only rationally.

The pulse of newborn children, then, is completly short and not distinct in its contraction and dilation. Herophilus says that this pulse is constituted “without definable ratios” [ἄλογον – álogon – lit. irrational]. He calls the pulse which is without relation to some ratio [πρός τινα ἀναλογίαν – prós tina analogían] a pulse “without definable ratios,” for it has neither a double ratio, nor a ratio of one and a half to one, nor any other proportion [ἕτερόν λόγον – heterón logon], but rather is completely short, and we observe it to be similar in size to the prick of a needle. For this reason Herophilus first called it “without definable ratios,” [ἄλογον – álogon] as one should. (Pseudo-Rufus, Synopsis de pulsibus, 4, ed. Daremberg p. 224-225, trans. Heinrich von Staden).

As a matter of fact, in a passage of De dignoscendis pulsibus Galen wonders, on an empiricist basis, how the latter could determine a primary “time-unit” that escapes perception.

How therefore was Herophilus first to establish some time-unit in relation to sense perception [sc. for the rhythms of the pulse], by which he, in measuring the other [time-lengths], claimed that they consist either of two or three or more [of these units], or [that these units] are both perfect and “not-subject-to-increase,” as they themselves [other physicians] call them, or decreased a little or a great degree or the greatest degree? He seems to write these things as though, in all pulses, he were accurately discerning the time-units either of their motion only or also of the pauses that follow the time-units of motion. (Galen, De dign. Puls., 3.3, 8.913, trans. Marquis Berrey, my mod.)

But Herophilus's view of the primary time-length is not either completely foreign to that of Aristoxenus, which had also a mathematical basis. The fact that he considers the pyrrhic as alogos is consistent with Aristoxenus' refusal to recognize it as a metrical unit. As von Staden notices, “the reason for both positions might be that there is no operation of real measurement against minima—no logos—in a sequence of two minima.” (von Staden, 1989, p. 281)

This conclusion seems to make irrelevant Berrey's view that “the prôtos khrόnos of the infant is a normative time [a rhythmic norm] for the infantile age-groups, but a standardized time [an objective time-unit] for the adult age-group” (Berrey, 2011, p. 72; 2017, p. 199). Contrary to Berrey's opinion that the infant primary time-length was actually perceived and used in practice by Herophilus, it seems that it was only an abstract requisit, a necessary mathematical origin of a numerical series supporting the pulse specification for all other age-groups.

The holistic part of the theory seems to unfold at the same varying distance from Aristoxenus. On the one hand, it endorses his definition of rhythm as “that which arises whenever the distribution of [time-lengths] takes on some definite arrangement” and comes back to perception data. The progressive theoretical construction of the pulse rhythm as “arrangement of primary time-lengths” is supported by a thorough observation of the pulse itself and of its specificity in each age-group. It reflects the actual development of the body and is therefore considered as based on nature. But on the other hand, Pseudo-Rufus' account reveals that Herophilus restricts the proportions between the various time-lengths of the pulse to the four binary Greek meters, and therefore that he does not use Aristoxenus' theory, which described also larger meters, in its full extent.

But when one's age progresses and one's body comes into its full growth, the pulse, too, increases with reference to ratio, getting a dilation which is proportionately more extended than the contraction. [It is possible, moreover, to establish their proportions using as means of demonstration the scansion that belongs to grammarians] [ἐκ τοῦ ποδισμοῦ τῆς γραμματικῆς – ek toû podismoû tês grammatikês]. You see, the first pulse found in newborn children will have the rhythm of a short-syllabled metrical foot, since it is short in both dilation and contraction, and it therefore is conceived of as consisting of two [short] time-units, whereas the pulse of children who are growing is analogous to the metrical foot [known] among them as trochee. This pulse consists of three time-units, holding its dilation for two time-units, but its contraction for one. And the pulse of those in the prime stage of their lives is equal in both, that is, in dilation and contraction, and is compared to the foot called spondee, which is the longest of the disyllabic feet. It is actually composed of four [short] time-units. This pulse Herophilus calls “in equal quantity” [διὰ ἴσου – dià ísou]. The pulse of those who are beyond their prime, and almost old, is itself also composed of three time-units, holding its contraction for twice as long as the dilation and longer. (Pseudo-Rufus, Synopsis de pulsibus, 4, ed. Daremberg p. 225, trans. Heinrich von Staden, my mod.).

Von Staden has proposed an excellent summary of this passage that gives all information we need, except maybe that it does not put enough emphasis on the novelty of the idea, compared to Aristoxenus, of the concurrently mathematical and biological development of a series of rhythms out of an originary point, with no ratio, i.e. out of a rhythm with no rhythm.

The normal pulse rhythm in infancy is analogous to the metrical foot known as pyrrhic (u u). [...] In growing children and adolescents the natural pulse rhythm has become trochaic (– u). Each cycle of diastole and systole now consists of three primary units, the dilation lasting for two units, the contraction for one. By the prime of life, the normal pulse rhythm consists of four primary time units equally divided between contraction and dilation, hence this is the spondaic stage of life (– –). [...] Finally, those who are beyond their prime and, as Rufus (or Pseudo-Rufus) puts it, “almost old people,” have entered an iambic (u –) stage of life. Their pulse consists of three primary time units, as in adolescence, but in an inverse ratio: the dilation lasts for the duration of one unit, the contraction twice as long (or even longer). (von Staden, 1989, p. 280-281)

We can now better assess Herophilus' pulse rhythm theory from its bottom to its top. While most of the time taking observation into account, Herophilus uses both rational-mathematical reconstruction, Aristoxenus' theory of rhythm, and some elements of the most common metric model in his time. He also uses his own contribution to the theory of the living. This elaborate construction allows him to rebuild the concept of rhythm, which only appeared at first as one of the four aspects of artery pulse, into a central category opening upon a completely new medical conception of human life based on four stages, differentiated by their specific pulse rhythms.

This seems to shed light on the fact that rhythm appears either last or first in Herophilus' list of the pulse aspects. It also brings an answer to Galen's legitimate and revealing question: “Why does he say that pulses in the same rhythm [ἐν ταὐτῷ ῥυθμῷ – en tautôi rhuthmôi] differ in speed, size, and vehemence?” (Galen, De dign. puls., 4.2, 8.959-960, trans. Heinrich van Staden) It really looks like rhythm has become for Herophilus a kind of overarching category.

As Berrey puts it, “the age-groups determine the normative differentiae of the pulse” (Berrey, 2011, p. 56). Since these age-groups are first determined by their characteristic rhythm, all others differences seem to be classified according to this primary difference.

A newborn has a normative pulse described in terms of size, speed, vehemence, and rhythm; a teenager has a normative pulse described in separate terms of size, speed, vehemence, and rhythm; and so on for each group. (Berrey, 2011, p. 56)

Strikingly, Berrey notices that “rhythm seems to be the only differentia of the four laid out in the beginning of Herophilus' On Pulses (namely size, speed, vehemence, and rhythm) in which the extant evidence shows that Herophilus attempted to provide normative evaluations in the usual terminology of health and illness” (Berrey, 2011, p. 86). The calculation of the ratio of the dilation length to that of contraction, and its comparison with the rhythm (size, speed, and strength) considered as normal in a particular age-group allow to observe the extent of a pathological state. Health and illness thus depend on the deviation of the pulse rhythm from the norm per age-group.

This rhythmic pulse lore is the main reason that made Herophilus famous for centuries. His work On pulses set a model for the use of rhythm as arrangement of meters in medicine and biology that was to last at least until the 16^th century.

Now we can come back to the still uncertain relation between rhythm and frequency. This relation was indeed to allow—if well after—another significant change in rhythm theory when, in the 18^th and 19^th centuries, the metric and rhetoric models were abandoned in life science in favor of mathematical models. Rhythm would not mean any more metric arrangement of time-lengths but sheer frequency or rate.

Let us consider Herophilus' unique construction of a portable water clock or clepsydra. This clock could be precisely calibrated to fit the age-group of each patient and seemed to have been commonly used to assess the state of the patients by measuring the frequency of their pulse.

There is a story that Herophilus had such a confidence in the frequency of the pulse, using it as a reliable diagnostic sign, that he constructed a water-clock capable of holding a specified amount for the natural pulses of each age. And, upon entering to visit a patient, he would set up his water-clock and feel the pulse of the person suffering from a fever. By as much as the movements of the pulses exceeded the number that is natural for filling up the water-clock, by that much he declared the [patient's] pulse too frequent—that is, that [the patient] had either more or less of a fever. (Marcellinus, De pulsibus, 11, ed. Schöne p. 463, trans. Heinrich von Staden)

This device, whose configuration is carefully described by Berrey who compares it to the Egyptian devices of the same period (2011, p. 75-80), was used to measure the deviation of the frequency of the patient's pulse from normal frequency in each age-group and thus to measure, in particular, the patient's body temperature or fever, since Herophilos held pulse frequency to be a correlate of body temperature and age (Von Staden, 1996, p. 89).

Referring to this clock and more generally to Herophilus' pulse rhythm theory, Pigeaud emphasizes that Herophilus' work was one of the first and the most successful attempts “to apply measure to the diversity and fluidity of the body” and therefore “to introduce quantity into biological sciences” (Pigeaud, 1978, p. 261). Von Staden plainly agrees with this view. He particularly stresses Herophilus' tendency “to quantify and mathematicize aspects of both the exterior and the interior of the body, including its internal motions” (Von Staden, 1996, p. 88), even if he rejected exaggerated mathematicizing and—following in this respect, some Hippocratics—leaved ample room for individual variability.

This tendency was in tune with a trend in ancient Greek science that Geoffrey Lloyd and others have shown to be much more powerful than it was commonly admitted. While the Hippocratics used to quantify pharmacology, stages of the embryo, and periodicities that appear in physical disorders such as fevers, Herophilus extended “the process of measuring into small interior structures of the body and into individual internal physiological and pathological processes” (von Staden, 1996, p. 88).

His attempts to measure bodily processes are perhaps also to be understood in the context of the renewed, more extensive preoccupation with scientific measurement in the third century BC. Eratosthenes' On the Measurement of the Earth, Aristarchos's On the Sizes and Distances of the Sun and the Moon, Archimedes' On the Measurement of the Circle, and Erasistratos's quantitative experiments are among the many manifestations of this interest. (von Staden, 1996, p. 88)

What does this context tell us about the relation between rhythm and frequency? Did this “preoccupation with scientific measurement,” which was most common in the 3^rd century, have an impact on the concept of rhythm by integrating in it, somehow, frequency?

Von Staden seems to consider them to be different but articulated: “Here [in Marcellinus' testimony], the pulse rhythms of different ages are not at issue [...] but the frequencies with which these rhythms occur” (von Staden, 1989, p. 283). The observation of frequency would complement that of rhythm “over a longer span of time.”

Herophilus' application of a theory of four stages of life to pulse-lore accordingly is based not only on those different rhythmic patterns within a single pulse-beat that were discussed above (trochee, spondee, etc.), but also on differences in the frequency with which these “rhythmic” beats occur over a longer span of time. (von Staden, 1989, p. 283)

Berrey proposes a slightly different view. He first insists on the difference between the measure of the pulse frequency and that of the pulse rhythm.

Frequency, the differentia measured by Herophilus' water-clock is different from the differentia of rhythm measured by Aristoxenus' protos chronos. (Berrey, 2011, p. 74 – see also p. 75, n. 59)

But in the end he suggests, since both imply the use of “normative time-units,” that “Herophilus' water-clock's normative use of time parallels Herophilus' use of Aristoxenus' theory of musical rhythm” and, therefore, that there is “a conceptual continuity between these two attempts to measure the timing of the pulse” (Berrey, 2011, p. 81). In other words, rhythm and frequency may be both taken as “covering pulse timing” (p. 58).

As we know, the Aristoxenian concept of “primary time-length” was not an absolute time unit. Any “primary time-length” could be uttered, sung, played or danced in a variable “objective” time laps, depending on the choice of the performer. This meant that the tempo of a particular rhythm could change according to the occasion. But what was of no consequence in an artistic performance and could even be taken as a necessary requirement, was in medicine cause of inaccuracy and could hamper a correct diagnosis. It is therefore quite possible that Herophilus felt necessary to add to his measure of the pulse rhythm, mainly based on the ratio between systole and diastole, a measure of the pulse frequency, based on the number of diastoles during a fixed laps of time.

While there is no evidence that the introduction by Herophilus of frequency had a direct impact on the rhythm concept itself, his attention to frequency certainly prefigured its future development in medicine. Without joining in the “Whiggish historiography” which Berrey quite rightly rejects (2011, p. 58), it can be assumed that Herophilus may have possibly complemented the “ancient metrics” (based on poetry, dance and music and simple arithmetical proportions) by a “more modern” one (based directly on mathematics and on the continuous series of numbers) without confusing each other.

Rhythm as Theoretical Stake

To finish this chapter dedicated to the introduction of rhythm in medicine and life science, I would like to address the question of the intricate concept interchange that supported it. As was shown above, we have good reasons to believe that the first occurrences of the term rhuthmós that popped up in some texts produced by the Aristotelian milieu were probably not genuine and were borrowed from exterior contributions coming most probably from the Alexandrian medical school. Conversely, Herophilus' pulse lore would have probably not been possible without the Aristotelian school's contribution concerning rhythm. Von Staden, on the one hand, Wellmann, Pigeaud, and Berrey, on the other, have developed opposing views on Herophilus' debt towards Aristoxenus. But both views may actually be conflated since Herophilus clearly borrowed some important conceptual tools from Aristoxenus without yet reproducing his theory in all points, choosing only those he found useful and otherwise producing by himself those he could not find in his predecessor.

Berrey is certainly right when he underlines the sociological basis of these intricate conceptual interchanges. However, I would not argue, as he does, that

the terms ῥυθμός, ἄρσις, and θέσις are technical language because of the specificity of their usage within a certain sociolect, the domain of practicing musicians and musical theorists. The technical terms point both toward the sociolect, the technical language of the techne, and the social group employing them, the technitae. Therefore the terms ῥυθμός, ἄρσις, and θέσις are part of the technical vocabulary of practicing musicians. (Berrey, 2011, p. 62)

This view seems too limited in various respects. Firstly, the milieu interested in rhythm was much larger than that of the musicians: the whole intellectual milieu under Aristotelian influence—on both sides of the Eastern Mediterranean—was sharing this common interest. Secondly, other philosophical schools were also interested in rhuthmós. As we saw above, Leucippus and Democritus used it in their theories, and it will be also extensively reused by Lucretius during the 1^st century BC. Thirdly, the sociological view somehow freezes the circulation of concepts by reducing them to sheer technicalities, assigning them to a limited social group, and finally erasing the struggles to appropriate them. No critique of traditional science history can develop efficiently without recognizing the complex conceptual genealogies it is made of, i.e. the triumph and spread of certain conceptual paradigms, the defeat and momentary or definitive disappearance of others, and the constant and erratic shifts and intertwining of meanings.

In this regard, we should emphasize that when Herophilus borrowed concepts from the theory of music, and particularly from the theory of rhythm that had been elaborated by Aristoxenus just a few decades earlier (ca. 360 – ca. 300 BC), it also borrowed indirectly from Plato and the most Platonic parts of Aristotle's work. It therefore put aside all Aristotelian rhetoric and poetic elaborations of rhythm—for instance as a holistic and performative meaning complex—as well as all Democritean contributions, in favor of an already heavily Platonized music theory supported by a reductionist semiotics.

This metric and semiotic Platonic bias is particularly visible in two fragments of the Pseudo-Galen's Medical Definitions (2^nd c. AD) which bear witness both of its origin and of its spreading in the 3^rd and the 2^nd centuries. The author tells us that Bacchius of Tanagra (275 – ca. 200 BC) and Zeno (end of 3^rd c. – beg. of 2^nd c. BC), who were both direct followers of Herophilus, defined artery rhythm respectively as follows:

Rhythm is a motion which has an order in time [κίνησις ἐν χρόνοις τάξιν ἔχουσα – kínêsis en khrόnois táxin ékhousa].

Rhythm is an order of time-lengths or an order in the duration in which occurs the diastole and systole of arteries. [τάξις τῶν χρόνων – táxis tôn khrόnôn]. (Pseudo-Galen, Medical Definitions, K XIX, p. 408-409, quoted by Pigeaud, 1978, p. 263, my trans.)

The first definition is obviously borrowed from Plato's Laws: “the order of motion is called rhythm” (τῇ δἡ τῆς κινήσεως τάξει ῥυθμός ὄνομα εἲν – têi dê tês kinêseôs táxei rhuthmόs όnoma eìn) (Plato, Laws, 664a-665a, trans. R.G. Bury). And the second is a direct translation from Aristoxenus' definition of rhythm as “that which forms each time that time is divided into fractions” that was recalled above.

In other words, it should be emphasized that Herophilus' contribution consisted in accommodating in medicine and life science a concept of rhuthmós, which was at odds with its older materialist understanding as well as with its more recent Aristotelian poetic definition, and that by promoting the former it contributed to the vanishing of the latter. Even later physicians as Erasistratus (ca. 304 – ca. 250 BC), who considered atoms to be the essential body element, would not use the term rhuthmós in a Democritean sense any more but in the Platonic-Aristotelian sense that was transmitted to them by Herophilus.

During the 3^rd century BC, the Platonic metric paradigm began to spread out of the three domains from which it originated: dance, music and poetry—the main “rhythmizable matters” according to Aristoxenus. It penetrated rapidly—and definitively—into life science and medicine and began to bounce back into philosophy.

Herophilus seems to have been instrumental in this extraordinary mutation. He imaginatively brought together Platonic-Aristotelian conceptual features and empirical data resulting from his careful observation of the human body. He was the first to compare the pulsation of the arteries to musical and metric rhythm. Instead respiration probably seemed to him too irregular and possibly discontinuous to perfectly match the new paradigm, but it was soon to be “rhythmized” by some Aristotelian scientists.

By using the term rhuthmós to designate medical and physiological phenomena which were not hitherto considered as rhythmic on the sole ground, as Benveniste put it, that they constituted “continuous activities” that could be divided “by meter into alternate times,” Herophilus' On Pulses, the Peripatetic School's Problems, and the Peripatetic Anonymus' On Breath definitively acclimated the concept of rhythm—under its Platonic form—to medicine and life science, but they also initiated a very long process of generalization that made it eventually fit to any reality, be it human or cosmic, cultural or natural, individual or collective.

One can now talk about the “rhythm” of a dance, a walk, a song, a diction, a work, anything that requires a continuous activity divided by meter into alternate times. The notion of rhythm is now fixed. From ῥυθμός as spatial configuration defined by the arrangement and proportion of distinctive elements, one reaches the “rhythm” as configuration of movements ordered in time [la durée] [...], “all rhythm is measured by definite movement.” (Aristotle, Problemata, Book 5, 882b 2) (Benveniste, 1966, p. 335, my trans.)

From Herophilus' time on, the expansion never ceased, reaching little by little more uncharted territories. As we shall see when we look into Vitruvius' contribution, it was even to penetrate into some arts and practices devoid of any relation to time, as architecture. After a long period of relative stability during the Middle Ages, it resumed during the Renaissance leading to the emergence of a modern “pan-rhythmism” that reached its climax at the end of the 19^th century.

Next chapter

[1] For this section, I used von Staden's thorough study of Herophilus' works: von Staden, Heinrich. 1989. Herophilus: The Art of Medicine in Early Alexandria, Cambridge, Cambridge University Press and also Marquis Berrey's more recent research on Alexandrian science: Berrey, Marquis. 2011. Science and Intertext: Methodological Change and Continuity in Hellenistic Science, Phd Dissertation, The University of Texas at Austin; and Berrey, Marquis. 2017. Hellenistic Science at Court, Berlin/Boston, De Gruyter.

[2] Heinrich von Staden's (1989) collection collects 44 fragments of Herophilus related to pulse theory, drawn mostly from Galen. All references to Galen's work will be to title, book, chapter, then volume and page in Khün's edition (1821-1833).

[3] Contemporary medicine uses the terms of diastole and systole in reference to the movement of the arteries, but those of dilation and contraction in reference to the heart's pumping motion.

[4] Von Staden (1989) translates plêthos either as “mass,” which is not very clear, or as “volume” [of water?], which is close to Berrey's “amount” (2011).

[5] According to Scarano, Pseudo-Rufus was “a follower of the Herophilean sect flourishing in Rome at the time of Galen.” Scarano, Giovanni Benito. 1990. “Sulla Sinopsi dei polsi attribuita a Galeno e a Rufo d'Efeso.” Med. nei Sec. N.S. 2, p. 93–112.

The Spread of Rhythm in Life Science and Medicine (1st – 2nd century AD) – part 1

Pascal Michon — 2017-12-14T20:00:00Z

Previous chapter

During the first two centuries of the current era, the Roman Empire was under the rule of the Principate. The tremendous civil violence that marred the end of the Republic disappeared. The whole Mediterranean was unified and the exchange between the Greek Eastern and the Latin Western worlds flourished. The Roman aristocracy was entirely “domesticated” but benefited from this period of peace, growth and intercultural exchange to develop new behaviors and interests. Concurrently with its particular attention to rhetoric as educational means, in which rhythm had a considerable share, it was also very much interested in Greek medicine where rhythm had also become essential.

Our knowledge of the medical pulse theory during the first two centuries of the Roman Empire is based on a fair number of specific treatises. Galen himself wrote in Greek at least six of them that are usually referred to by their Latin name: De pulsibus ad tirones – On Pulses to Beginners; De pulsuum differentia – On Differentiae of Pulses; De dignoscendis pulsibus – On Distinguishing Pulses (all three in vol. 8 in Kühn's edition, 1824); De causis pulsuum – On Causes in Pulses; De praesagitione ex pulsibus – On Prognosis of Pulses; Synopsis librorum suorum de pulsibus – Synopsis on Pulses (all three in vol. 9 in Kühn's edition, 1825). These texts have not been translated into English but they exist in a Latin translation made during the Renaissance. The most modern edition was published by Karl Gottlob Kühn between 1821 and 1833. There is also an English summary of the treatises made by John Redman Coxe in 1846.

In addition to those texts, there are five other treatises of the same period dedicated to the pulse. Three of them are attributed to Galen and published in Kühn's edition (vol. 5 and 19) but are probably not from his pen: De pulsuum usu – On the Use of Pulses; De pulsibus ad Antonium disciplinae studiosum et philosophum – On Pulses to Antonius philosopher and eager student; Definitiones medicae – Medical Definitions. Three more treatises were written under the same title On pulses by Pseudo-Rufus of Ephesus, Pseudo-Soranus and Marcellinus.

Strikingly, most of theses treatises have been written over a period of a little less than a hundred and fifty years. Marcellinus lived between the late 1^st and early 2^nd century AD; Pseudo-Soranus and Pseudo-Rufus of Ephesus probably in the 2^nd century AD; and Galen from ca. 129 to 216 AD. This number of extant works developing the Herophilean pulse lore, often quoting and discussing each other, shows that there was, during this period, a surge of interest in this subject among Greek-Roman physicians—and their clients—and that the pulse was considered both an important theoretical and clinical subject, a phenomenon difficult to perceive and on which physicians often disagreed, and also quite certainly an ostentatious sign of the physician's special knowledge that was meant to impress his patients.

This does not mean, naturally, that the Herophilean pulse lore had been forgotten during the previous centuries. On the contrary, there is enough evidence that shows a continuous and vivid debate about pulse and rhythm. But as for the founder himself, nothing remains from the works of previous Greek physicians interested in this matter. We only know about them through the 2^nd century AD treatises which often quote them quite accurately but necessarily in a very limited extent.

Contestation vs Refinement of the Herophilean Pulse Rhythm Theory – The Pneumatic School (1^st cent. AD)

A few testimonies seem to indicate that the Herophilean pulse lore was contested after the 3^rd century BC by non-Herophilean physicians, who found it too abstract to correctly account for the empirical phenomena they had to deal with and also too complicated to implement.

In his Naturalis Historia – Natural History, Pliny the Elder (23-79 AD) reports that, by his time, the Herophilean classification of pulse according to age and rhythm—which he seems strangely to partly confuse with speed—had been abandoned “on account of its excessive subtlety,” while the observation of pulse frequency and pulse strength still served as “a pilot in life.”

Between the nerves lie hidden the arteries, i.e. the ducts for pneuma. The veins, i.e. the channels for blood, float among them. The pulsation of the arteries is most apparent in the extremity of the limbs. In general, it is an indicator of diseases, and it was divided by Herophilus, an oracle of medicine, into definite measures and metrical laws according to age [in modulos certos legesque metricas per aetates]: regular, or in rapid motion, or slow [stabilis, aut citatus aut tardus]. But this [nowadays] is abandoned on account of its excessive subtlety; nevertheless, through our observation of the frequent or feeble beat [crebri aut languidi ictus] it [still] regulates the steering of one's life. (Pliny, Natural History, 11.89.219, trans. Heinrich von Staden)

In another passage Pliny says that Herophilus' rhythmic theory of pulse associating “ages” with certain types of “musical feet” was “abandoned in succeeding years” because “it necessitated a strong acquaintance with the belles lettres.”

These several schools of medicine, long at variance among themselves, were all of them condemned by Herophilus, who regulated the arterial pulsation according to [musical feet], correspondingly with the age of the patient [in musicos pedes venarum pulsu discripto per aetatum gradus]. In succeeding years [however], the theories of this sect were abandoned, it being found that to belong to it necessitated a [strong] acquaintance with [the belles lettres] [deserta deinde et haec secta est, quoniam necesse erat in ea litteras scire]. (Pliny, Natural History, 29.5, trans. John Bostock & H.T. Riley, my mod.).

A century later, Galen notices again that while there were still a certain number of physicians, as himself, advocating and using Herophilus' pulse rhythm theory, many others considered it too speculative and unefficient.

Some, however, proceed to a plausible account [sc. of quickness and slowness in pulse], writing systematic accounts of the Herophilean kind about the rhythms in pulses, while others both disparage such speculation as idle verbosity and distance themselves from it completely. (Galen, De praesagitione ex pulsibus, 2.1, 9.275, trans. Heinrich von Staden)

However, this contention against the Herophilean use of metric rhythm was neither complete nor definitive. Berrey provides a list of 19 Herophilean physicians from Herophilus himself (330/320-260/250 BC) to Demosthenes Philalethes (fl. 7 BC-50 AD), who most probably practiced medicine according to Herophilus' pulse lore (2011, p. 266-269). Moreover, von Staden suspects Pliny to be ignorant of the latest works of the “Pneumatic school of medicine” in which rhythm was indeed considered an important differentia and subject of much debate.

The statement that the strength and frequency of the pulse were still being used as diagnostic criteria, but that its speed had been abandoned—about rhythm and size, Herophilus' two other criteria, Pliny says nothing [unlike von Staden, I think that rhythm is clearly targeted by Pliny – PM]—can only mean that Pliny was not well informed about the efflorescence of pulse-lore in the Pneumatic school of medicine. (von Staden, 1989, p. 285, n. 158)

Indeed, the development of the pulse rhythm theory seems to have been already thriving in the Pneumatic school since its foundation in Rome by Athenaeus of Cilicia in the 1^st century AD. Some texts from the 2^nd century provides a few hints about this efflorescence which, according to Wilamowitz and Wellmann, was already well advanced in the work of Pliny's contemporary Agathinus (1^st century AD), although the pulse lore of Agathinus' pupil, Archigenes (33/34 or 53/54-116/117 AD), is much better documented (von Staden, 1989, p. 285, n. 158).

Pseudo-Rufus of Ephesus, who according to Scarano (1990) was “a follower of the Herophilean sect flourishing in Rome at the time of Galen” reports a list of categories that was used by Archigenes and probably other members of the Pneumatic school before and after him. As in Herophilus' fragment that was commented above, rhythm is listed last, which may indicate that it was still considered to be of special interest.

The ten species of pulse, according to Archigenes, are determined: 1. by the quantity of the dilation; 2. by the quality of the movement; 3. by the intensity of the strength; 4. by the amount of the beat; 5. by the duration of the rest; 6. by the consistency [of the artery]; 7. by equality and inequality; 8. by regularity and irregularity; 9. by fullness and emptiness; 10. by the rhythm. (Pseudo-Rufus, Synopsis on Pulses, ed. Daremberg, p. 231-232, my trans)

A fair number of pieces of evidence shows that rhythm began to be an object of fierce conceptualization. First, its various definitions were discussed with great care.

Rhythm, says Bacchius the Herophilean, is a motion which has a definite order in time [κίνησις ἐν χρόνοις τάξιν ἔχουσα – kínêsis en khrόnois táxin ékhousa]. The Herophilean Zeno says: the rhythm is an order of time-lengths [τάξις τῶν χρόνων – táxis tôn khrόnôn] or an order in the duration in which the dilation and the contraction of the arteries occur. However, it would be more accurately defined as follows: rhythm is the proportion of the pulse time-lengths that have a certain relationship to each other. Another has defined it in these terms: the rhythm is the configuration of times from the moment when the arteries dilate until they contract. (Pseudo-Galen, Medical Definitions, 220, 19.408-409, my trans.)

Pulse rhythm admitted new subcategories. In a fragment transmitted by Galen, Archigenes recollects Herophilus' list of four primary criteria—size, speed, vehemence, and rhythm—to which he adds four subsidiary criteria which all seem to be related to rhythm—order [taxis] and disorder [ataxia]; evenness [homalotes] and unevenness [anomalia].

Although Herophilus expounded the other differences between pulses by genus as follows, namely by “size, speed, vehemence, and rhythm,” he also mentioned [order] [taxis] and [disorder] [ataxia] and evenness [homalotes] and unevenness [anomalia] by species without combining them [sc. into genera]. (Archigenes quoted in Galen, De diff. puls., 2.6, 8.592-593, trans. van Staden, my mod.)

Finally, since the pulse rhythm constituted a sign of the patient's health or pathological state, a new series of semiological-rhythmical categories was elaborated on the basis that each age-group had its own typical rhythm. In his Synopsis on Pulse, Pseudo-Rufus suggested to differentiate between a “eurhythmic” pulse “which, in each age, preserves its natural progression” and a “pararhythmic” one which does not.

It is necessary to know that, in all kinds of pulses, one distinguishes size, speed, fullness and rhythm. A great pulse is that of which one feels by the touch, in a marked way, the length, the breadth and the depth. A full pulse is the one that strikes the fingers with strength and is tense like a nerve. A pulse whose rhythm is regular is that which, in each age, preserves its natural progression; it is called eurhythmic; conversely, that which does not keep this regular progression is called pararhythmic. The rapid pulse is the one that quickly withdraws from the fingers; speed and frequency differ: speed can be recognized by a single beat; it takes several to assess frequency. (Pseudo-Rufus, Synopsis on Pulse, ed. Daremberg, p. 228-229, my trans.)

The Pseudo-Galenic Medical definitions, a treatise which was written during the same period, is even more precise. It differentiates between “arhythmic,” “cacorhythmic,” “pararhythmic,” “heterorhythmic,” and “ecrhythmic” pulses according to their varying deviations from the “eurhythmic pulse” in which the rhythm is normal considering “the age of the patient, the temper of the year and all other conditions.”

The eurhythmic pulse is one which has the rhythm appropriate to the age of the patient, his natural constitution, to the temper of the year and to all other conditions.

The arhythmic pulse is one which has no rhythm and nothing appropriate.

The cacorhythmic pulse is one which has the rhythm contrary to the eurhythmic.

I call pararythmic the pulse which has in some measure the rhythm appropriate to the age of the patient but not always. I call heterorhythmic the pulse whose rhythm is that of another age. The ecrhythmic pulse is one whose rhythm does not correspond to that of any age, or any other condition. (Definitiones medicae in Galen, ed. Kühn, 221-222, 19.409-410, my trans.)

In all these new elaborations, rhythm was still defined in Herophilean terms as proportionate organization of time-lengths, but it was now the center of a web of concepts that irrigated the whole medical theory and practice.

It is worth noticing though that, as in Herophilus' time, there is no evidence that rhythm was already in any way conflated with frequency and that it began consequently to lose its classical metric basis for a more mathematical one. Although Herophilus' measurement techniques of the pulse frequency seem to have had mixed success among his successors—even in the Herophilean sect, none of his followers seems to have employed his water-clock—the usefulness of this measure was still recognized and extensively debated. However the debate was not about the distinction or similarity between frequency and rhythm but between frequency and speed, the former denoting the number of dilations during a certain amount of time, while the latter referred to the quickness of the artery dilation. According to Wellmann, all of Book 5 of Archigenes's On Pulses was devoted to discuss the latter difference. Similarly, von Staden notices that the same distinction played a prominent role in the Galenic treatises (1989, p. 284, n. 156).

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The Spread of Rhythm in Life Science and Medicine (1st – 2nd century AD) – part 2

Pascal Michon — 2017-12-14T19:30:00Z

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Refinement and Canonization of the Herophilean Pulse Rhythm Theory – Galen (129-ca. 200/216 AD)

The Greek Κλαύδιος Γαληνός – Klaúdios Galênós, Anglicized as Galen, was born in Pergamon in the first half of the 2^nd century AD. He died in the first decades of the following century. He studied and traveled widely in the Roman Empire before settling in Rome, where he served prominent members of the Roman society and was finally given a position in the imperial court as personal physician to several emperors, among others Marcus Aurelius and his son Commodus.

As his immediate Pneumatic predecessors, Galen acknowledges Herophilus' groundbreaking achievement concerning the observation of pulse rhythm. He is also willing to accept his basic definition of rhythm as “ratio of the time of the motions.”

Let it the be established, for practical purposes, that rhythm consists in the ratio of the time of the motions [τοῦ χρόνου τῶν χινήσεων τὸν ρυθμὸν συνὶστασθαι – toû khrόnou tôn khinêseôn tòn rhuthmòn sunístasthai], since we will at some point make a separate inquiry about Herophilus' view. (Galen, De dign. puls., 3.3, 8.912-913, trans. Heinrich von Staden)

He develops a similar classification of pulse rhythms according to the degree of deviation from “natural rhythm.” According to him, the pulse rhythm can be either “natural,” when the patient is sound, or “contrary to nature,” when he or she is ill. In this case, it can be either “pararhythmic” (with the smallest deviation), “heterorhythmic” (with a greater deviation), or “ecrhythmic” (with the greatest deviation). It is therefore a very precise and irreplaceable diagnostic technique.

In comparing the time of dilation [of the pulse] to the time of the contraction, as Herophilus thought one should, it can be recognized that the ill person has [a pulse] contrary to nature [παρὰ φύσιν – parà phúsin], and in addition that it is greatly or negligibly contrary to nature [παρὰ φύσιν – parà phúsin]. For, great deviations from the natural rhythms [τῶν κατὰ φύσιν ῥυθμῶν – tôn katà phúsin rhuthmôn] into that which is contrary to nature [τὸ παρὰ φύσιν – tὸ parà phúsin] signify great harm, whereas lesser deviations signigy smaller harm. For the para-rhythmic pulses [οἱ παράῥυθμοι σφυγμοί – hoi parárhuthmoi sphugmoí] display the smallest deviation, heterorhythmic pulses [οἱ ἑτεροῥυθμοι – hoi heterorhuthmoi] a greater deviation, and ecrhythmic pulses [οἱ ἔκῥυθμοι – hoi ekrhuthmoi] the greatest. (Galen, Synopsis librorum suorum de pulsibus, 14, 9.470, trans. van Staden, my mod.)

Galen also notices in passing that it would be possible to apply Herophilus' pulse rhythm theory to respiration—showing incidentally that this association was not yet a regular feature in 2^nd century AD medicine. Contrary to what appears in von Staden's translation, who tries to be as clear as possible and expands Galen's somehow concise expression, he does not use the term “respiratory rhythm” but the idea is clearly already there.

It is clear that the same speculation as was recorded by Herophilus concerning rhythms in the pulse will await this part [sc. the parts used in respiration, since the respiratory “rhythms” of inhalation and exhalation are not unlike the diastolic and systolic rhythms of the pulse]. (Galen, De difficultate respirationis, 1.21, 7.812, trans. and com. Heinrich von Staden)

However, his relationship to Herophilus' pulse lore is not one of slavish imitation. He disagrees with him principally on three accounts although with varying intensity.

Firstly, as Pliny, he remarks that Herophilus' concept of rhythm has become difficult to understand because it necessitates the reader be correctly acquainted, thanks to a proper education, with rhythm in musical and poetic context. He also criticizes the systematic approach that is used by Herophilean physicians and accuses them to be so enchanted with Herophilus' rhythmic system that they cease to bother with predicting the course of the diseases they have to deal with and forget the very purpose the system was developed for. It seems, however, that both reproaches are addressed to his contemporary competitors, whose lack of culture and dogmatism he contemptuously mocks, more than to Herophilus whom he admires and considers as having cleverly taken “what was useful from the musicians into medicine.”

For this reason anyway whatever about rhythms of music they ought to have learned while they were still children in the schools they in no way bring to treatises of medicine, suffering the ill-effect of their late learning, nor can they keep silent, even if [the subject] belongs to another art. No one of them wrote how one ought to make meaning from rhythm. But Herophilus at least, going a route opposite to them, leaves out what someone worthily educated of the art should have learned from musicians, and speaks to them as if they understand, since he takes what is useful from them into medicine. But they, whenever they detail this amazing system [τεχνολογίαν – tekhnologίan]—as they call it— about rhythms, they no longer care to show how one might sufficiently make prognoses or interpret through these things. (Galen, De dignoscendis pulsibus 2.3, 8.871-872, trans. Berrey)

Secondly, Galen feels necessary to enlarge Herophilus's pulse definition (I am using for this section and the next Berrey, 2011, p. 215 sq.). Whereas the latter used four main criteria to differentiate between pulses (size, speed, strength, concerning one dilation beat, and rhythm concerning the relation between dilation and contraction), he sets up a classification based on eight generic differentiae (De pulsuum differentiis, 1.3, 8.501 and De pulsibus ad tirones, 2-7, 8.455-59). He first accepts size, speed, and strength of the artery's movement, and rhythm, which he defines, similarly to Herophilus, as the ratio of the time of dilation to the time of contraction. But he adds to this list two more groups of differentiae. One concerns the state of the artery: the hardness of its tunic; and the fullness of its body. The other strikingly complements the rhythmic measure by enlarging the observation over a longer series of beats: the frequency of the arterial beat and pause, which was also used by Herophilus without being considered a full differentia; and its regularity, which instead is an entirely novel feature ant tries to figure out if the beat, observed over a longer time, is regular, oscillating or totally irregular.

Since the artery has three dimensions, just as any other body—length and breadth and depth—it is entirely necessary that in each of the dimensions there be some quantity of dilation and contraction. It is further necessary that it have tension, either weak and faint, or readily and strongly active; and that the tunic itself of the artery either be soft or hard, but that the internal width either be empty somehow or full; and that in all these things there occurs at some time a regularity and at some time an irregularity; and that there be some ratio of the time-unit of the dilation to that of the contraction; and that beyond these no other differentia can occur in one pulse. (Galen, De pulsuum differentiis, 1.3, 8.501, trans. Marquis Berrey)

Actually the only point on which Galen really disagrees with Herophilus concerns the measure of rhythm. He contends that Herophilus' view is somehow confusing. The latter does not clearly say whether he thinks of it only as “a ratio of the time of dilation to the time of contraction” or as a more complex measure that would encompass also “the time of rest which follows upon each of the two motions.”

In all these things many insoluble difficulties necessarily occur in the [medical] factions in differentiation of rhythms, and I think it is for this reason that physicians after Herophilus did not even attempt to write anything on prognosis based on rhythms. And while Herophilus himself in many places mentions rhythms with a view to prognoses, it is very difficult to discover just what he means by “rhythm” [τὸν ῥυθμòν– tòn rhuthmòn]: is it the ratio [τὸν λόγον – tòn lógon] of the time of dilation to the time of contraction only, or does he also attribute to “rhythm” the time of [rest] [ἠρεμίας – êremías] which follows unpon each of the two motions? This is where there is no agreement, not even among those who are named “Herophileans” after him, concerning just what Herophilus really thought about rhythms. For his words do not indicate one of the two alternatives clearly, nor is the nature of these things capable of providing confirmation. (Galen, De dign. puls., 3.3, 8.911-913, trans. Heinrich von Staden, my mod.)

Whereas his predecessor distinguished only two kinds of arterial motion, Galen emphasizes the need to pay attention to the pauses or inactive intervals in the pulse cycle. He identifies four times in each cycle of arterial pulsation: dilation / pause / contraction / pause. The rest following dilation he calls ἡ ἐκτὸς ἠρεμία – hê ektòs êremía – external rest, because it happens at the peak of the artery's outward expansion toward the touch of the physician. The other following contraction he calls ἡ ἐντὸς ἠρεμία – hê entòs êremía – internal rest, because it happens at the nadir of the artery's inward contraction away from the touch of the physician (Berrey, 2011, p. 52, n. 7).

He also notices that the first part of the dilation and the final part of the contraction are almost imperceptible (De discognendis pulsibus, 3.3, 8.909-910). The only part that can be measured with accuracy is the final part of the dilation (De discognendis pulsibus, 3.3, 8.903). This leads, Galen notices, to the unsatisfactory conclusion that, according to Herophilean standard, the rhythm could be accurately measured only in vehement pulses, without incidentally being determined precisely enough since the perceptible part of dilation would be taken in relation to all the remaining parts, namely contraction and the two rests (Berrey, 2011, p. 216).

His own solution to the problem is exposed at the very end of Book 3 of On Distinguishing Pulses. He proposes to measure each dilation and contraction relatively, from whatever part of it can be perceived by touch. Should the physician want to rate, for instance, the pulse speed, he may content himself with rating the dilation fast, moderate, or slow, and doing likewise for the contraction. The combination of both arterial motions should then be located among those on a chart reproduced here below that is applicable for any pulse except the dullest, whose parts are not perceptible. The physician thus avoids the problem initially identified: the impossibility to measure the entirety of the arterial motions. In Galen's method there is no need to measure the full cycle, since any perceptible part is taken to stand for the whole (Berrey, 2011, p. 217).

What meaning each differentia has we will make clear in On Prognosis. But now we will first subscribe the chart, since it will be readily clear to those trained in the first book of On Differentiae of Pulses. Following we will say in what way again many differentiae exist differing from each other in quantity, even if they are of the same kind.

This empiricist stress on perception results in a critique of Herophilus' descriptions of pulse rhythm that are deemed too vague even if the concept of proportion of time-lengths can be useful.

It became clear, on the basis of the things he [Herophilus] did teach, that he is confused and does not clearly articulate the distinction between contraction and rest [pause]. For, if he actually thinks that a contraction which is extended for as long as ten primary time-units can arise in old people, he very clearly is not perceptive about what a contraction really is. You see, sometimes it is of shorter duration than the dilation, sometimes of equal duration, and at other times, as he writes, of longer duration—but not, as he thinks, five times as long; rather, only a little more. (Galen, De praesagitione ex pulsibus., 2.3, 9.278-279, trans. Heinrich von Staden)

It also results in the rejection, as too simplistic and inadequate, of Herophilus' use both of the Aristoxenian quasi-mathematical concept of πρωτος χρόνος – prôtos khrónos—“we had no need of primary time-unit”—and of the four binary metric feet as main types of arrangement of the prôtoi khrónoi.

Instead Galen elaborates a very refined classification of rhythmic cycles which presupposes their very variability without losing its precision. “Many differentiae”—unfortunately he does not list them but we may also think of size and strength—are to “differ from each other in quantity, even if they are of the same kind.” Galen takes again the example of the speed of the successive motions (dilation and contraction), which can be rated as greater or smaller “by a small degree” or “by a lot.” Therefore, whereas Herophilus, using elementary arithmetics, measured very simple ratios of time-lengths (1/1, 2/1, 2/2, 1/2), Galen introduces the idea, presupposing a more advanced mathematics, that rhythm should be defined as ratio of varying quantitative measures.

Since the first differentiae written in the chart have a fast motion, it indicates that the motion in dilation is spurred on to the greatest degree, and the motion in contraction is greater by a small degree than the moderate and medium motion, or on the other hand that the motion in dilation is greater by a little, and that the motion in contraction is much greater or both are greater by a little or both by a lot, or the one by a little, the other by a lot, or less by a little or by a lot, or however else. The variety is obvious. It is not possible to say either that this seems not to happen, or that it has no meaning. For indeed it happens and very much has meaning. For us it sufficed to make prognoses from this distinction, since we had no need of primary time-units, both whole in their parts and enlarged [τῶν πρώτων χρόνων ὁλοϰλήρων τε ϰαὶ παρηυξημένων – tôn prôtôn khrónôn holoklêrôn te kaì parêuxêménôn]. That such a distinction needs no entire motion but can become clear to anyone through a chance part of it, except if it should be unequal (for then the part is not equal to the whole). Moreover not even in very dull pulses is it possible to employ this method. For it is not possible in the case of these pulses to recognize the first beginning of the contraction, not any part of it is worthy of record. (De dignoscendis pulsibus, 3.3, 8.915-916, trans. Marquis Berrey)

It has often been claimed that some of these complex rhythms were given by Galen evocative names, sometimes borrowed from the Pneumatics, because they were easy to remember: “goat-like,” “ant-like,” “worm-like,” “rat's tail-like,” etc. Some 19^th century commentators viewed these names as “charming metaphors” that “naturally” could not be used any longer by “modern science.”

But one may also notice that in Galen's new account rhythm becomes less static and more dynamic, less mechanical and more “life-like,” and that may explain why he chose metaphors referring the most typical complex pulses to animal movements implicating both varying ratios between dilation and contraction, frequency, and more or less regular succession of beats. The pulsus caprizans, for instance, was named after the goat because it had a double impulse, a small one followed quickly by a larger one, before coming down again—like the leap of a goat. The fatal pulsus vermicans and formicans resembled the frenetic movement of a worm or that of an ant. The pulse myuri was like the movement of a rat tail since it gradually became smaller, and in like manner recovered its magnitude gradually, and so on alternatively.

Furthermore, since it presupposes that the ratio determining the rhythm concerns varying quantitative measures, it cannot be reduced anymore to rational numbers or simple fractions, and must admit irrational solutions. Considering Galen's care in describing the variation of the difference between the various quantities of the dilation and the contraction—“ that the motion in contraction is much greater or both are greater by a little or both by a lot, or the one by a little, the other by a lot, or less by a little or by a lot, or however else” —one even wonders if the proto-calculus developed by Archimedes might not be here at work beneath the surface. This would need to be investigated more thoroughly than I can afford here. Suffice it to note, for the time being, that these phenomenologically animal-like and mathematically irrational rhythms could be easily represented with graphs. Joseph Struthius who wrote an Ars sphygmica in 1540 seems to have been the first to attempt at a graphic representation of the form of the pulse derived from his study of the movement of a leaf laid on a superficial artery (Fleming, A Short History of Cardiology, 1997, p. 20). In his Medicine dissertation (Berlin, 1866 quoted in Deichgräber, 1981, p. 294, n. 1), Otto Schadewald has proposed a very suggestive graphic model for the pulsus caprizans showing a repeated sequence of double impulses in the dilation followed by a swift contraction.

It is most unlikely that Galen ever graphed or even imagined such kind of oscillating curves which began to be commonly available only with Carl Ludwig's Kymograph (1847) and Etienne Marey's Sphygmograph (1860). But, just as Herophilus who introduced frequency as a significant aspect of pulse rhythm without yet making it part of its definition, Galen certainly provided, with his improved quantification technique, new elements prefiguring the future mutation of the concept of pulse rhythm from a succession of time-lengths organized according to metric proportions, in the Ancient poetic and musical sense, to a more modern metric model based on continuous repetitive variations.

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The Spread of Rhythm in Life Science and Medicine (1st – 2nd century AD) – part 3

Pascal Michon — 2017-12-14T18:00:00Z

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Pulse Rhythm as Part of a Mind-Body Identity Theory? – Galen

Let us turn now to the philosophical correlates of this change in the theory of rhythm. To get a clearer picture we need first to come back to the use of its musical counterpart—the concept of harmony—in philosophy (for the next paragraphs, I am using Pigeaud, 1978). The comparison of the soul with musical harmony, which most probably originates in Heraclitus (frg. 51) and Pythagoras, is exposed by Simmias in Phaedo as follows: since the soul resembles the harmony of the lyre, it is invisible and divine ; but once the lyre has been destroyed, the harmony vanishes ; therefore it is most probable that when the body dies, the soul too vanishes. This view is strongly refuted by Socrates-Plato on the ground that the soul is immortal (Phaedo, 85e) and in turn by Aristotle who advocates the soul as Form of the body (De anima, 1.4, 407b and 2.1, 412a).

Strikingly, it seems that the metaphor of the soul as harmony was first used by Materialist thinkers and rejected by Idealists as well as Aristotelians. As a matter of fact, according to Cicero (106-43 BC), when Aristoxenus developed it further, it was on a clear materialist basis.

One very old [among the definitions of the soul], held by Aristoxenus, a philosopher as well as a musician, considers the soul as a kind of tension of the body itself [ipsius corporis intentionem – intentio probably for ἔντασις], analogous to what in song and instrumental music is called harmony: answering to the nature and conformation of the whole body, vibrations of different kinds are produced just as sounds are in vocal music [sic ex corporis totius natura et figura uarios motus cieri tamquam in cantu sonos]. (Cicero, Tusculanes, 1, 10, 19, my trans.)

Lactantius (ca. 250-ca. 325 AD), who was a fierce opponent of materialism but a good observer, is even more precise concerning the play of this bodily harmony.

What about Aristoxenus? For him, just as the tension of the strings of a lyre produces a system of harmonious sounds [sed sicut in fidibus ex intentione neruorum effici concordem sonum atque cantum] that the musicians call harmony [quem musici harmoniam uocant], so consciousness [uis sentiendi, lit. power to perceive] results from the conformation of the viscera in the body and the respective strength of the members [ita in corporibus ex conpage uiscerum ac uigore membrorum uim sentiendi exsistere]. (Lactantius, Institutiones Divinae, 7, 13, quoted by Pigeaud, 1978, p. 264, my trans.)

From these pieces of evidence, it appears that Aristoxenus held the soul to be located in the body, precisely in the brains (Pseudo-Galen, 19.315) or at the basis of the brains (circa cerebri fundamentum) (Tertullianus, De anima, 15, 5). It was nothing, as Lactantius put it, but a uis sentiendi or a sensation resulting “from the [harmonious] conformation of the viscera in the body and the respective strength of the members,” in other words from the dynamic state of the organs.

What happened to rhythm, during this metaphorical translation of the concept of harmony, is much less well documented and need further inquiry. Yet, one wonders if Herophilus' transfer of musical rhythm into physiology and medicine did not trigger, on the philosophical level, a kind of parallel analogy: if the soul resulted from the “harmony” of the organs, could not the organs, at least the heart and the arteries, give their “rhythm” to the soul as well?

Although we do not have direct evidence concerning Herophilus, it seems most likely that he found in Aristoxenus' theory of rhythm the same incentive to think materialistically about the soul as in his theory of harmony. Consequently, the soul may well have been for him a “sensation” resulting from the “concord” of the organs as much as from the “rhythm” of their activity.

This hypothesis seems to be validated by certain features of Galen's conception of the relationship between body and soul. This subject has been much debated and the picture is far to be completely clear, but some points in it are quite suggestive (for the next paragraphs I am using Singer, 2016).

For a long time, Galen has been considered as a proponent of a mind-body identity theory, which as far as we are concerned implied that the variation of the pulse rhythm was related, in some ways, to that of the soul. Singer recognizes that for Galen “mental capacities [were] physically conditioned.” Maybe for the first time in the West, “he [explored] the subject in an empirically and physiologically informed manner.” (Singer, 2016)

Galen's theory is indeed heavily influenced by Herophilus' and Erasistratus' major medical discoveries concerning both the organs and the channels through which they operate.

This crucially included the discovery of the nervous system, as well as some detailed knowledge and theorization of the anatomy and functions of the brain (all, of course, quite unknown to Plato, with whose theory Galen attempts to harmonize them). Galen's conception of brain, heart and liver as “sources” (arkhai) of the three Platonic parts of the soul is inextricably linked with his anatomical understanding of the three sets of channels (nerves, arteries, veins) through which they operate. (Singer, 2016)

The philosophical Platonic tripartition of the soul is now translated into a physiological triad. Reason, spirit, and desire are located “in, respectively, the brain, the heart and the liver.”

The three parts—rational (logistikón), spirited (thumoeidês), desiderative (epithumêtikón)—correspond to and are located in, respectively, the brain, the heart and the liver. These are the central organs in Galen's physiology, responsible respectively for: rational thought, perception and voluntary motion; involuntary motions (especially pulse and respiration) necessary to the maintenance of life; and blood-production and nutrition. (Singer, 2016)

Each one of these psychic entities presupposes a corporeal counterpart. For instance, the hêgemonikón – leading part, command center of the soul—which is equated by Galen with Plato's logistikón – rational—is responsible for intellectual activity and memory, for voluntary motion and for perception. But each one of the latter is also to be understood in terms of brain and/or nerve function.

The strongest case for a mind-body identity theory in Galen, however, is provided by the discussion of the relationship between rational soul and physical features of the brain. The central aim of that work is to demonstrate the extent of the influence of the body, specifically bodily mixture, on the soul; this Galen does with examples from medicine (e.g., mental derangements with physical causes) as well as everyday experience (drunkenness, effects of physical environment). How, he asks, could a soul which is not corporeal be affected by such physical factors, and indeed be caused to leave the body as a result of certain physical conditions? In a number of passages, he suggests not just the dependence of the soul on bodily mixture, but the identity of the two. (Singer, 2016)

Similarly, the fact that the thumoeidês, which encompasses a range of emotional reactions related to anger, indignation, shame, pride, anxiety, fear, is located in the heart, is shown by a number of examples, both from everyday experience and from traditional thought, in which the pulse plays an important role. (Singer, 2016)

Singer recalls that Galen exemplifies and expounds this view at length in his refutation of Chrysippus. Such relationships between physical states and mental ones are also explored in a range of medical texts too. Galen makes interestingly precise attempts at identifying physical correlates for a range of psychological or emotional states, in terms of the precise actions and states of heart or blood. Relevant here too are the medical discussions in which it is clearly implied that certain types of physical state—e.g., excess of melancholic humors—are causative, if not constitutive, of certain mental states.

In order to unite his theories about the soul, Galen renovates the old theory of the pneûma, which he elaborates further to explain how the soul operates within its assigned organs, and how these organs, in turn, interact together. In Galen's new physiology, the body is the framework of intertwined flows, of which some are flowing continuously and other rhythmically. He distinguishes the psychic pneûma (πνεύμα ψυχικóν – pneûma psukhikón), which is produced in the brain and flows through the nervous system; the physical pneûma (πνεῦμα φυςικóν – pneûma phusikón) which is produced in the liver and brings blood and nutrition to the body through the veins; and the vital pneûma (πνεῦμα ζωτικóν – pneûma zôtikón), which is in turn produced in the heart and flows rhythmically in the arteries.

In short, the very tripartition of the soul between three organs, the attention paid to the physiological flows that link them with the body, and the correlations between a range of physical and psychological or emotional states, seems to suggest a “mind-body identity theory.”

It is tempting, in view of the correlations that Galen explores, both between the functioning of the rational soul and states of the brain, and between emotional disturbances and states or activities of the heart and blood, to see him as advancing either some form of dual aspect theory or, indeed, a mind-body identity theory. (Singer, 2016)

However we are warned that Galen's conception of the relation between body and mind is far from monolithic. It actually constitutes a “complex” theory—in the modern sense of a system of interacting parts endowed with internal tension—basically because it is trying to harmonize Plato's view on the soul, and the Idealist ethics which is based upon it, with more recent anatomical and physiological discoveries, which on the contrary have more or less Physicalist implications.

Concurrently with the Hellenistic medicine of Herophilus and Erasistratus, Galen's theory is heavily influenced by his Platonic and Aristotelian philosophical background. This may account for the fact that Galen's theory is not completely “clear and consistent” (Singer, 2016), especially concerning the respective roles of the three psychic organs—heart, liver, and brain.

Galen refutes the contemporary Stoic view of the hêgemonikón as located in the heart, as against the Platonic-Galenic view of its location in the brain. This leads him to hold “a unitary view of the soul and its ‘command center.'” Yet concurrently, he maintains that the “physical location of the other two Platonic soul-parts, spirited and desiderative (respectively, heart and liver)” still plays an important role. But, he is not able to make the same close connection between the liver and the heart and their psychological functions as he is for the brain. “The texts in question are unclear on the precise nature of the causal (or identity) relationship.” (Singer, 2016)

From all available evidence, one may conclude that, on the philosophical level, Galen does not advocate any longer a firm materialist position as his predecessors, and therefore a direct correlation between heart, pulse rhythm and soul dynamic. In medical and physiological contexts, Galen seems to hold an “interactionist” view of the relation between body and mind, i.e. of two separate entities that are at the same time inseparable, firstly, because the psukhê is distributed between three bodily organs; secondly, because it operates through the intertwined flows of various kinds of pneûma, some of which move rhythmically; thirdly, because there is plenty of evidence of their constant interaction. But as far as the essence of the soul/mind is concerned, he is more of an agnostic. He maintains “the identity of the mortal parts [sc. the non rational parts as those located in liver and heart] of the soul with bodily mixtures,” but he leaves open “the Platonic possibility that the (rational) soul is a non-bodily substance” and therefore immortal. (Singer, 2016)

A consideration of all the relevant evidence, however, leads to a less clear-cut picture. The apparently clearest identity [of mind and body] statements come in dialectical contexts; it is at least arguable that Galen is here asserting the identity position not as his own but as the correct Aristotelian conclusion, on the basis of their equation of soul with form. Other passages, meanwhile, clearly affirm the identity of the mortal parts of the soul with bodily mixtures. Now, this certainly includes the non-rational parts; but, within this same text, Galen leaves open the Platonic possibility that the (rational) soul is a non-bodily substance. Such indeterminacy is consistent with his explicit statements of ignorance on this very question, the “substance of the soul”. Other relevant evidence is the lack of clarity, in the medical texts mentioned above, as to the causal relation between mental events and physical correlates; and that some kind of interactionist picture seems implied by statements about the mutually beneficial relationship of soul and body and of their respective training. (Singer, 2016)

In other words, Galen is certainly the most important heir and transmitter of the Hellenistic medicine and its broad materialist orientation, but he is also one of the most powerful agent of its re-Platonization. He certainly not professes himself to be an Idealist but the space he provides to significant Platonic views is sufficient to allow a stronger return in the next centuries. While he suggests that the rhythm of the heart and of the arteries are correlated with the state of the soul, he limits it to its “spirited part.” Moreover, his explanations of their interaction are much less clear than those he gives for its “rational part” located in the brain. Finally, since he maintains the possibility of an immortal soul, at least of a part of it, it is no wonder that he sometimes opens the possibility to think of the “pulse rhythm” not any more in a methodological way designed for diagnosis purposes but as an essence or a reality per se replicating the periodic movements of the heavenly bodies.

Although sometimes this permanent regularity [of the succession of the dilation and the contraction] goes astray and some irregular motion occurs, just as we can observe in planets or in wandering stars a circular regularity [in circuitibus paritas], just like these very planets according to which we say “as orderly as the motion of the Planets,” so is the pulse, which is like a going round [περιόδους ἴσων – periódous ísôn]. (Galen, Synopsis librorum suum de pulsibus, 6, 9.445, my trans.)

The Growing Naturalization of Pulse Rhythm from the 3^rd cent. AD

From the 3^rd century AD, there was a growing naturalization of the pulse rhythm theory. Ironically, what was only meant by Herophilus and even, at least partly, by Galen, on a Materialist basis, as a technical concept intended to regularize observation and help diagnosis, began to be considered as natural. Rhythm which was quite consciously borrowed from theory of poetry, music and dance, i.e. as a culturally defined category, began to be taken as rooted in nature. According to this trend of thought, the arteries would move according to natural musical or metric rhythms. There would naturally be music and poetry in our body and this music would naturally be related with the cosmic music of the spheres.

In his treatise on time and divisions of time De die natali, Censorinus (first half of the 3^rd century AD) revisits Herophilus to claim that “the pulsations of the veins move in musical rhythms.” If Pythagoras could put himself to sleep by playing cithara and Asclepiades of Bithynia (124-ca. 40 BC) restore the minds of delirious people with music, this is because there is musical rhythm “in our veins” and harmony “in the movement of both the body and the soul.” The conclusion is clearly Platonic: since each individual has music in him, he must be linked somehow with the music of the cosmos. “Then doubtless music [musica] is not alien to the days of our birth.”

[This is why Pythagoras, who wished that his soul should be always imbued with the sentiment of divinity, had, it is said, the habit of playing the cithara before abandoning himself to sleep.] And the physician Asclepiades restored the minds of people suffering from phrenitis [delirium]—minds agitated by disease—to their own nature through musical harmony [per symphonian]. But Herophilus, who practiced the same art, pretended that the pulsations of the [veins] [venarum pulsus] move in musical rhythms [rhythmis musicis ait moveri]. If, therefore, there is harmony in the movement of both the body and the soul [si et in corporis et in animi motu est harmonia], then doubtless music [musica] is not alien to the days of our birth. (Censorinus, De die natali, 12, 4-5, trans. von Staden, my mod.)

Similarly, in his commentary on Martianus Capella (ca. 360-ca. 328) the neo-Platonic Latin prose writer, Remigius of Auxerre (ca. 841 – 908), a Benedictine monk during the Carolingian period, praises Herophilus for having examined “the rhythms of the veins.”

Herophilus used to examine the bloodvessels of the ill through a comparison of their rhythms [aegrorum venas rhythmorum]. (Martianus Capella, De nuptiis Philologiae et Mercurii, 9.926, trans. von Staden)

There is evidence that this Platonic trend may also have developed branches very early among Persian and Arab physicians such as al-Razi – Rhazes (865-925), Ibn Sina – Avicenna (980-1037), Ibn Zuhr – Avenzoar (1094-1162), and Ibn al-Nafis, (1213-1288), who were eventually followed by the Unani medicine that was practiced in Mughal India and Muslim cultures in South Asia (beg. of 16^th cent. – mid-19^th cent.).

This trend in Islamic medicine should be one day researched thoroughly and naturally confronted with other evidence showing the development of empiricist views and even some anti-metaphysical stands. But we know that Avicenna, who was, as a physician, strongly influenced by Galen and, as a philosopher, by neo-Platonism, explicitly compared pulse rhythms to musical rhythms in his famous Qānūn fī al-Ṭibb – Canon of Medecine. The pulse embodied the intimate correspondance between microcosm and macrocosm. By virtue of its rhythmic quality, numerical proportions, and circular regularity, it was inherently musical (Farage, 2008, p. 24).

You should know that there is in the pulse a musical nature [quod in pulsu reperitur natura musice], for as the art of music is realized [ars musice completur] [in the melody] according to the relation between them as to high pitch and low [per adiunctionem sonorum secundum proportionem comitantem eos inter acuitatem et gravitatem], and in the [rhythmical] recurrence of time-intervals between the striking [per circulos casuum et temporum qui sunt inter eorum percussiones], so it is with the pulse [sic est dispositio pulsus]: its temporal relation [proportio suorum temporum] in respect of [speed, regularity, weakness and quantity] [in velocitate et spissitudine et debilitate et in quantitate] is a [proportional, sc. rhythmical] relation [est sicut proportio adiunctionis eius]. (Avicenna, Liber canonis, Lugduni, opera Jacobi Myt, 1522, lib. I, Fen 2, Doctr. 3, Dict. 2, Sum. 1, trans. Leofranc Holford-Strevens, my mod.)

Since the translation of the Canon into Latin by Gerard of Cremona (ca. 1114-ca. 1187), Avicenna provided what may be the first list to become generally available in the Latin West of the five particular musical proportions said to be involved in the pulse: (2/1), (3/2), (4/3), (5/4) and (5/2). These proportions were selected from and adapted to the numerical proportions suggested by Galen with the intention, which was not that of Galen, of forming a musical series (Siraisi, 1975, p. 699).

In the West, according to Nancy Siraisi, the belief that music is inherent in the beating of the pulse “was widely held throughout the Middle Ages” (Siraisi, 1975, p. 689). She provides an impressive list of Western medieval music theorists who asserted “the inherence of music in bodily parts and functions, usually the virtues and humors and/or pulse”: Aurelian of Réôme (fl. c. 840-850); Remigius of Auxerre (ca. 841-908); Honorius of Autun (1080-1154); Hugh of St. Victor (ca. 1096-1141); Richard of St. Victor (d. 1173); Jerome of Moravia (d. af. 1271); Bartholomeus Anglicus (ca. 1203-1272); Iacobus de Ispania (d. af. 1330) (Siraisi, 1975, p. 689, n. 1).

Numerous brief but explicit statements of this belief, and of the associated ideas that music is present in other bodily rhythms and or in the virtues and humors can be called from the writings on music and music theorists and encyclopedists. For such writers, the idea of the musicality of pulse was, of course, one specific expression of the more general notion that musical harmonies inhere in the body and soul of man. (Siraisi, 1975, p. 689)

Siraisi also shows an extraordinary surge of interest for “the music of pulse” in Northern Italy between the 13^th and 15^th centuries in a milieu of physicians and university professors. She studies thoroughly the various contributions of Pietro d'Abano (ca. 1257 – 1316), Gentile da Foligno (d. 1348), Jacopo da Forli (ca. 1360 – 1414), Ugo of Siena (d. 1439), and Pietro Vermiglioli (fl. 1480).

She notices that passages on pulse rhythm in Galen's works and in Avicenna's Canon were repeatedly discussed and elaborated further by these physicians.

Each of the authors named devoted between one and five folio pages to the discussion of the music of pulse, and all of them formally endorsed the concept, although with varying degrees of qualification. Their opinions ranged from the apparent enthusiasm for the harmonies of the universe and the music of pulse displayed in the lengthy and learned exposition of musical theory provided by Pietro d'Abano to the disinterest and probable skepticism evident in the much briefer account by Gentile da Foligno. (Siraisi, 1975, p. 691)

In the Conciliator differentiarum philosophorum et medicorum – Conciliator of the Differences between Philosophers and Physicians, Pietro d'Abano gave “the most extended and perhaps the mosts influential treatment of the subject” (Siraisi, 1975, p. 691). He was a professor of medicine, philosophy, and astrology at the University of Padua. His contribution opened a two centuries-long debate among Italian physicians while fixing its main outlines.

First, d'Abano provides the readers with a few practical definitions of consonance and dissonance and an account of the mathematical proportions used in music, but he pays particular heed to large Idealist definitions of music borrowed from Augustine (354-430 AD), Boethius (ca. 480-524 AD) and Isidore of Seville (ca. 560-636 AD).

Second, regarding rhythm in particular, although, reenacting some of Galen's own reflections, he voices a debate on the right manner to measure it—is the diastole to be compared to diastole or systole to systole or diastole to systole? Should the stroke be compared to the rest immediately following it? Or is diastole plus rest to be compared to systole plus rest?—the proportions between durations are held to be, as in Avicenna, distributed according a fixed mathematical and musical scale: (2/1), (3/2), (4/3), (5/4) and (5/2).

Third, due to the Idealist foundations of the medieval musical theory but also to the development of the new polyphonic practices of the ars nova, there is a contamination of the concept of rhythm by that of harmony.

At the end of Antiquity, as we will see, Boethius (ca. 480-524 AD) already claimed that “the whole union of our body and soul is by means of music. For the disposition of the body itself contains it; even so is the heartbeat [pulsus cordis] set in motion [...] The condition of our soul and of our body seems in a certain way to be composed according to identical proportions” (De institutione musica, 1.1). Presumably, the pulse fell into the category of musica humana, the function of which was to “mix the disembodied life of reason with the body,” to join the rational and irrational parts of the soul, and to “mingle together the elements of the body” (quot. and trans. Siraisi, 1975, p. 703). Rhythm itself was overlooked in favor of harmony, i.e. proper concordance of magnitudes and multitudes. Similarly Cassiodorus (ca. 485-ca. 585 AD) declared that “the science of music is diffused through all the acts of our life for this reason: if, in the first place, we do the will of the Creator [...] Indeed, whatever we say or whatever is inwardly moved by the pulsing of the veins is proved to be associated through musical rhythms with the power of harmony [per musicos rithmos armoniae virtutibus probatur esse sociatum]” (quot. and trans. Siraisi, 1975, p. 702).

But, at the end of the Middle Ages, due probably to the joint teaching of music and medicine in the Italian universities, this association of rhythm and harmony is brought a step further. The pulse itself, like the different voices of a group of singers, is deemed either “harmonious” or “dissonant,” and d'Abano uses indifferently such expressions as consonantia pulsualis or proportiones pulsuales (Pennuto, 2017, p. 63). The way is open for an increasing confusion between rhythm and harmony, the former being now considered as totally substitutable with the latter to the extent of their common proportional nature.

According to Gentile da Foligno (d. 1348), while variation of “speed and slowness” of the pulse remains analogous to variation of “proportion of sounds which has to do with the measuring of times of motion and rest,” i.e. what was properly called rhythm, its variation in “strength and weakness” are compared to variation in pitch of sounds, “according to high and low,” i.e. harmony.

A double proportion is attended to in musical sounds. One is that of the sounds themselves, because, that is, some are high and others are low. The other is the proportion of times. [...] And in the same way it should be understood that two kinds of proportion are found in pulse. One, that is, which corresponds to the proportion of sounds properly so called, that is, according to high and low. The proportion in pulse that corresponds to this is that between strength and weakness. [...] Similarly, in the second place, the proportion in pulse which is read according to speed and slowness corresponds to the proportion of sounds which has to do with the measuring of times of motion and rest. (quot. and trans. by Siraisi, 1975, p. 693)

But for Jacopo da Forli (ca. 1360-1414), “speed and denseness in pulse [themselves] are in some way like highness in tone. For the high tone moves the hearing quickly, but the low tone slowly. So the rapid pulse quickly impresses itself upon the touch” (quot. and trans. by Siraisi, 1975, p. 694). And one century later, quoting Avicenna, the Bolognese physician Giovanni Garzoni (1419-1505) similarly explains that the melodic proportions of the sounds as to high and low pitch match those in pulsu between the strength and weakness of the beat (Letterio, 1999, p. 249).

Finally, like in Boethius, body rhythm and harmony are related to those of the cosmos. D'Abano, who concurrently teaches medicine and astrology, claims that the movements in a sound human body are not only circular, repetitive and harmonious as those of the planets—“he names as parts of musica humana, the union of soul and body by mathematical harmonies; breathing; and, of course, pulse itself” (Siraisi, 1975, p. 704)—but that they are also directly influenced by them. Naturally there are some discussion among his followers about the way this influence may happen but whatever their personal philosophical opinion—the followers of Plato starting from the heavenly spheres and Ideas, i.e. from musica mundana; the followers of Aristotle starting from the sublunar world and the sensible phenomena, i.e. from musica instrumentis then renamed musica organica—all agree on a model of the human body whose physiology is playing, singing, or beating a natural music.

Between the 3^rd century BC and the 1^st century AD, Herophilus' pulse lore was discussed and sometimes rejected, but it was also the subject of new practical inquiry and theoretical elaboration, especially in the Pneumatic school of medicine with the works of physicians such as Agathinus and his pupil Archigenes. In this context, rhythm became a basic concept for medical semiology.

The 2^nd century AD was a period of extraordinary efflorescence, due mainly to the work of Galen, but also to such authors as Marcellinus, Pseudo-Rufus of Ephesus, Pseudo-Soranus, and Pseudo-Galen. Elaborating further the concepts produced by their predecessors, these physicians laid the foundation of a sophisticated theory of pulse rhythm. They refined Herophilus' fundamental contribution, transformed it into a kind of medical canon, and ensured its extraordinary spread in the West—and beyond.

But Galen is also partly responsible for the twist in the medical research, which made it, at least to a certain extent, abandon its Empiricist and Materialist foundations in favor of more Idealist ones. The Platonic concept of rhythm which had been acclimated in medicine initially out of practical reasons, began as soon as the 3^rd century AD to be considered, concurrently with harmony, as naturally and really existing in the body, and therefore as replicating or expressing in it the “music of the cosmos.” As we shall see in the next chapter, this trend anticipated the development of a larger Platonic movement in the 3^rd and the 4^th centuries AD

Eventually, the Galenic legacy has been as long as rich. Galen's medical works and those of other authors that were attributed to him were regarded as authoritative until well into the Modern Times. They heavily influenced medieval Islamic medicine and became the mainstay of the medieval physician's university curriculum. During the Renaissance, they were translated from Greek into Latin and were still commonly studied in medical schools until the 18^th century. They largely spread the Herophilean pulse rhythm theory—most ot the time in its re-Platonized version but not always—all over Islamic and Western scientific culture.

Next chapter

Rhythm from Ratio to Beat – Modern Medicine (1540-1628)

Pascal Michon — 2017-12-14T17:30:00Z

Sommaire

Previous chapter

Medicine and some of its discipline-sisters as anatomy and physiology have been instrumental in the history of rhythm in Modern Times. Along with music, which will be only briefly touched upon because it would necessitate a complete essay and also because it exists already a good number of studies on the subject, they have transmitted and spread its Platonic and Aristotelian definition. Since métron – measure was the core of the Platonic definition of rhythm, I entitled this section “The Spread of Metron.” But, medicine, anatomy and physiology have also been witness of a complex semantic history during which a bunch of new meanings have been added to the original concept, while older ones disappeared. This is the intricate history with which I would like to begin our journey.

Matching Pulse and Cosmic Cycles – Rhythm as Ratio (6^th cent. – early 17^th cent.)

As we saw in the previous volume, after Galen's ambitious theoretical synthesis in the 2^nd century AD, which was, in the main, still faithful to Herophilus' pulse lore (3^rd cent. BC) (chap. 4), there was a deep shift in the medical and physiological definition of rhythm during the 3^rd and the 4^th centuries AD (chap. 7).

Under the influence of a strong neo-Platonic trend that submerged the last period of the Roman Empire, the concept of rhythm, which originally had been transferred from poetry, music and dance theory into medicine, undoubtedly under its Platonic and Aristotelian guise but out of sheer methodological and practical concern, was fully essentialized and naturalized. Whereas it was meant to help assessing as correctly as possible the varying diagnostic quality of the pulse, it was now increasingly considered as existing per se.

In Boethius' De institutione musica (ca. 480-524 AD), which remained a regular academic textbook throughout the Middle Ages, the rhythms of the body were directly related with those of the cosmos. The human microcosm was emulating the rhythms of the macrocosm. Thus rhythm, which had been considered by Herophilus and still by Galen as varying proportion between time-lengths, began to imply a succession of cycles and return of the same and be subjected to the concept of harmony (chap. 9).

We should be careful not to conflate all medieval opinions concerning the pulse since there is evidence of some physicians' strong empiricism and disbelief concerning its so-called “musicality.” Nancy Siraisi cites, for instance, Ibn Rushd – Averroes (1123-1198) and, in the West, Gentile da Foligno (d. 1348) as expressing a certain skepticism concerning the music of pulse (1975, respectively p. 700 and 692). This is something that remains to be studied in detail. However, it seems that in the West as well as the Islamic world with Ibn Sina – Avicenna (980-1037), the Idealist belief that music was inherent in the beating of the pulse was widely shared throughout the Middle Ages (Siraisi, 1975, p. 689).

This opinion was naturally held by music theorists, encyclopedists, natural philosophers, and even some theologians. Siraisi provides an impressive list of authors who endorsed this view: Aurelian of Réôme (fl. ca. 840-850); Remigius of Auxerre (ca. 841-908); Honorius of Autun (1080-1154); Hugh of St. Victor (ca. 1096-1141); Richard of St. Victor (d. 1173); Jerome of Moravia (d. af. 1271); Bartholomeus Anglicus (ca. 1203-1272); Iacobus de Ispania (d. af. 1330) (1975, p. 689, n. 1).

But, at least from the 13^th century to the 16^th century, it was also supported by many physicians and medical writers who appropriated previous suggestions exposed by Avicenna in his famous Canon which had been translated into Latin by Gerard of Cremona during the second half of the 12^th century. In Northern Italy, the “music of pulse” was widely discussed among physicians and university professors of medicine who set up “a fairly continuous tradition” (Siraisi, 1975, p. 689).

Pietro d'Abano (ca. 1257-1316) was the first of a long series of medieval Italian physicians to put emphasis on this theme. He paid particular heed to the Idealist definitions of music elaborated in the late Antiquity by authors such as Augustine (354-430 AD), Boethius (ca. 480-524 AD) and Isidore of Seville (ca. 560-636 AD) (see vol. 1, chap. 9). He claimed, following Avicenna, that the proportions between durations were distributed according a fixed mathematical and musical progressive scale: (2/1), (3/2), (4/3), (5/4) and (5/2). He strengthened the idealization of the concept of rhythm, which had already partly integrated the meaning of return, repetition, by subjecting it further to the concept of harmony. Finally, coming back to Boethius' Idealist view, he strongly emphasized the relation between the musica humana and the musica mundana, making the pulse rhythm a direct replica of the cosmos rhythm.

To tell the truth, Siraisi notices a tendency among the Italian physicians of the 14^th and 15^th centuries to reduce “the music of pulse” to a mere technical comparison aiming at interpreting it as a mere sign of the state of the body. However, none of them seems to have been able to overthrow the neo-Platonic beliefs which structured their mental framework and to adopt a plain empiricist viewpoint.

Ultimately, theirs criticisms were practical and derived from experience, being based on common-sense conclusions about music and pulse. Yet they were unwilling to abandon an established branch of theoria solely on account of practical considerations. Thus, although modified, the musicality of pulse, a concept with decidedly neo-Platonic overtones, continued to be asserted by physicians trained in Aristotelian natural philosophy. (Siraisi, 1975, p. 709)

Although both Galen's medical doctrine and Boethius' neo-Platonic philosophy began to be severely criticized in the 16^th century, the link between pulse rhythm, music rhythm and cosmos rhythm remained a medical cliché at least until the early 17^th century.

It still marred the first use since Herophilus of a clock for timing the pulse made by Johannes Kepler (1571-1630), the astronomer, at the beginning of the 17^th century. Unlike his predecessor who, in the 3^rd century BC, employed a water clock (see vol. 1, chap. 4), Kepler used a modern clock driven by a falling weight and found a pulse rate of 70 per minute common. However, he thought that it “should” be 60—one per second—in a mystical relationship with the movements of the heavenly bodies (Fleming, 1997, p. 17).

Do the sections of equinoctial hours match the human pulse?

In the vigorous, robust, and mature man, of melancholic temperament or growing old, almost every second there occurs one pulsation of the arteries [fere singulis secundis existunt singuli pulsus Arteriae], without any distinction being made between systole and diastole, that is sixty pulsations in one minute. It is rarely slower; usually it is 70 [vulgariter numerantur 70]; in bilious temperaments and women it is 80, four in every three seconds. In short, there is more or less four thousand pulsations in one hour. (Johannes Kepler, Epitomes Astronomiae Copernicanae, Linz, 1618, 1.3.3, GW, vol. 7, p. 180, my trans.)

Although Kepler discovered the laws of planetary motion which provided one of the foundations for Isaac Newton's theory of universal gravitation, empirical evidence was not yet strong enough to balance his belief in a mystical link between pulse and cosmic rhythm. Consequently, the new sense of beat, measure and frequency, which was soon to become a dominant aspect of the rhythm concept in medicine, was still enveloped in the older sense of ratio, periodicity and cosmic revolutions.

Noting the Pulse – Rhythm as Ratio (Struthius and Mercado – 1540-1584)

The medical belief in the music of pulse and its astrological correlates, which incited to conflate the concept of rhythm with that of period or cycle, had a late Scholastic counterpart which transformed the notion of ratio itself.

This trend was illustrated in the 16^th century by two authors: the Polish physician Josephus Struthius – Józef Struś (1510-ca. 1569) who published in 1540 Sphygmicae artis iam mille ducentos annos perditae et desideratae which was reprinted many times (I used the 1573 edition); and the Spanish physician Luis de Mercado's (ca. 1525-1611) who published in 1584 De pulsus arte et harmonia – On the Art of Pulse and Harmony, which I will not comment since it heavily borrowed from Struthius' work and did not add anything new to it (for a presentation see Pennuto, 2017).

Struthius was professor of medicine in Padua (1535–1537) and personal doctor of Polish kings. He also served as mayor of Poznań. De Mercado was protomédico general to the Kings of Spain and Portugal Philip II et Philip III, and professor at the university of Valladolid.

Struthius, was extremely conservative in his thinking as well as in his medical practice. In his treatise, he referred mainly to Galen's teaching (see vol. 1, chap 7). The main differentiae in the human pulse were its quantity, speed, frequency, and strength, the quality of the arteries (cf. table p. 8), and the order or disorder in the succession of pulsations (p. 12-13). Concerning the concept of rhythm used by the physicians, he attributed its origin to music and not poetry—he did not mention the possibility that it may have been common to both because music and poetry were not originally dissociated.

The word rhythm is used in music, from which it has been transferred by physicians. But Pliny pretends that it derives from poetry and was termed in medicine after the metric laws. However, it usually means harmony, concord, number, skillful connection, modulation [consonantiam, concentum, numerum, concinitatem, modulum]. (Sphygmicae artis, 1573, p. 14-15, my trans.)

Modulus (small measure) and numerus recalled the Roman tradition (see vol. 1, chap. 6 sq.). Consonantia, concentus and concinnitas seemed instead more recent and borrowed from the new musical practices that developed from the 14^th century with the polyphonic music called ars nova—in which ars was to be understood as “skillful “technique” of associating sounds harmoniously as much as rhythmically.

Struthius strongly stressed the difference between music and medicine in which the rhythm was defined as “proportion between alternate times,” i.e. between the temporal quantity, i.e. duration of the dilation and the contraction of the arteries.

[In medicine] the correct definition of rhythm is [...] the proportion between the alternate times that make up the pulse [eorum quae in pulsu sunt temporum ad invicem proportio]. Proportion, according to Euclid, is the relation [habitudo] between one quantity with another of the same kind: because time belongs to the genus of quantity, [the physician] compares the quantity of the first time [the dilation] [quatitatem unius temporis] to that of the second [the contraction] [ad quantitatem alterius], to look if they are equal or if one of them exceeds the other. (Sphygmicae artis, 1573, p. 15, my trans.)

The most innovative part in Struthius' work concerned the measure of rhythm. In opposition to Galen's prejudice against the use of musical notation, he advocated the use of the contemporary musical mensural notation, which in this instance greatly enhanced the ancient metric notation.

Not only the alternation of dilation and contraction was comparable to that of “arsis seu elevatio” (upbeat) and “thesis seu positio” (downbeat), but it was possible to record their respective duration with musical note symbols like longa – quadruple whole note, brevis – double whole note, semibrevis – whole note, and minima – half note (p. 17-18).

The pulse rhythm naturally varied according to temperament, gender, age, season, and place. The pulse of infant, for instance, was composed of two successive minimae (half notes: relative duration = 1/2), i.e. ½/½; that of young people of two semibreves (whole notes: relative duration = 1), i.e. 1/1: that of adults of two breves (double whole notes: relative duration = 2), i.e. 2/2; that of the elderly of two longa (quadruple whole notes: relative duration = 4), i.e. 4/4 (p. 18).

The pulse rhythm was a meaningful sign of health and illness (p. 18). As long as the rhythm remained “equal” (aequalis), i.e. a fraction equal to 1, the patient enjoyed a “harmonious and ‘skillfully connected' rhythm” (consonus et concinnus), a eurhythmus, which was its rhythm of health (p. 19). But whenever, “because of an illness or for another reason,” his rhythm took a slower or faster pace, he could feel his health deteriorate. His pulse rhythm would become a pararhythmus, a rhythm close but not exactly corresponding to his age. For instance, in old people the pulse, which was normally composed of two longas (4/4) could become two breves (2/2). If the change brought the patient to a two minimae rhythm, typical of childhood (½/½), i.e. if the pulse quadrupled its frequency, his/her health was greatly in danger: for the elderly, it was indeed a heterorhythmus, a rhythm foreign to their age. Finally, if the rhythm became uneven and, in particular, composed of a brevis and a minima (2/½ = 4/1), or a semibrevis and a minima (1/½ = 2/1), the elderly was in the ecrhythmus, a rhythm which “did not belong to any age” (p. 19-20 – for the corresponding Galenic classification, see vol. 1, p. 282-284).

This seemed at first to be a simple translation into the new mensural notation from the old metric notation proposed by Herophilus in the 3^rd century BC and recapitulated by the pseudo-Rufus in the 2^nd century AD (see vol. 1, p. 156). But there were some noticeable differences with the Ancients' theory.

First, it implicated a different view of the life cycle. Whereas the Ancients observed a pyrrhic pulse (diastole/systole) in infancy (◡ ◡ : 1/1); a trochaic pulse in growing children and adolescents (– ◡ : 2/1); a spondaic pulse in adults (– –: 2/2); and a iambic pulse in old people (◡ –: 1/2), i.e. as a solar curve rising in the prime of life then falling down during old age, Struthius thought that the pulse was continuously enlarging and slowing down from ½/½ to 4/4, although he noticed, as his predecessors, that in elderly “the contraction could be longer and the dilation shorter” (p. 18).

The second difference was more important. Since they were using the metric poetic system, the ancient physicians had at their disposal a quite limited notation tool that allowed to note only four proportions based on 1 (◡ ) and 2 times (◡ ◡ or –). The new musical notation was much more versatile and precise since it allowed to combine four different kinds of time-lengths: minima (½ time); semibrevis (1 time); brevis (2 times); longa (4 times), making up at least 64 possible rhythms.

Last but not least, Struthius suggested to make the rhythm classification simultaneously empirically easier to use and closer to the Scholastic standard of rationality by basing it on a rigorous dualistic system. Instead of using only a scale graduated with increasing degrees of deviation measured against a eurhythmic norm, he proposed to develop a full rhythmic system, first by differentiating two branches grouping equal and unequal rhythms (aequalis/inaequalis rhythmus or pari/impari proportione), i.e. eurhythmus or ecrhythmus (“ecrhythmus sive inaequalis rhythmus” – p. 21), and by growing from those primary branches subsidiary branches based on opposite series of musical proportions.

Equal rhythms had dilation and contraction of equal durations, be they—“depending on age, region, temperament, and sex”—longam/quadruple whole note, breuem/double whole note, semibreuem/whole note, or minimam/half note (4/4, 2/2, 1/1, ½/½).

Unequal rhythms had unequal dilation and contraction, according to multiplex proportions, i.e. when a number contained an inferior number a certain number of times (1/2; 1/3; 1/4; 1/5 or 2/4; 2/6; 2/8; 2/10; etc. ); superpartialis proportions, i.e. when a number contained an inferior number and its half or its third or its fourth, and so on (3/2; 4/3; 5/4; 6/5; etc. called proportio sesquialtera; sesquitertia; sesquiquarta; sesquiquinta, etc. ); or even occulta proportions in which “either the time of contraction or that of dilation was hidden.”

In a typical scholastic manner, multiplying branches like the ornamentation of a Flamboyant cathedral, as Panofsky once put it for a previous period, Struthius added that there could be also “composite proportions (compositas proportiones) made of multiplex and superpartialis, or multiplex and superpartientis.” The superpartientis proportion was defined as the opposite of the superpartialis, i.e. the proportion between a number and another number containing the first one and several aliquot parts of it (2/3; 3/4; 4/5; 5/6; etc.). He summarized his view in a arboreal graph (see in Sphygmicae artis, 1573, p. 23).

Struthius added one more degree of complexity to his scholastic conceptual proliferating system by finally integrating in it a suggestion once made by Galen, in a quite different spirit as a matter of fact since it aimed at introducing ratios of varying proportions and certainly not at multiplying binary classifications (see vol. 1, p. 288). He proposed to differentiate both original branches of equal and unequal rhythms (rhythmi aequales/inaequales) not only according the ratio between the durations of dilation and contraction, but according to their respective speed (Sphygmicae artis, 1573, p. 26).

Struthius' rhythm theory was based on the typical medieval idea that Man was determined by series of numbers but he developed it according to the Scholastic method that was still in use in his Flamboyant time. The whole life of the human being was covered by a universal tree classifying rhythmic ratios, which decided between health and pathological state. In short, Struthius' Galenism was a cross between Boethiusian numerology and Scholastic logic.

However, although having a foot firmly planted in the past, Struthius heralded an important rhythmological change. While still being closely related to the periodic return of the heavenly bodies, and part of a dualistic Scholastic system, the concept of rhythm was now associated with a more precise measure of time. As a matter of fact, Struthius' treatise included the first attempt ever made at the graphic representation of the form of the pulse derived from the feeling of the fingers on a superficial artery.

Mechanizing the Pulse – Rhythm as Ratio (Harvey – 1610-1628)

With his Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus – An Anatomical Exercise on the Motion of the Heart and Blood in Living Beings, published in 1628 but which summarized studies probably started in 1610, William Harvey (1578-1657) definitively outdated Galen's physiological system.

For the sake of clarity, we must here enter into some details concerning the physiological theory of the time. Galen held that the blood flowed through two vascular systems, communicating through the septum of the heart (the wall between the left and right side of the heart), from heart and liver to all parts of the body where it was finally consumed. According to this system, that was considered authoritative throughout the Middle Ages and still late into the 17^th century, venous impure blood was first created in the liver from chyle coming from the intestines, imbued with the first vital form of pneuma allowing energy and growth, and transferred by the veins to the right ventricle of the heart. Arterial blood was then created by the purification of the venous blood whose impurities were exhaled through the lungs, then by the tricking through invisible “pores” or “channels” in the interventricular septum to the left ventricle. There, the blood was imbued with a higher spirited form of pneuma, drawn from the outside via the pulmonary artery by inhalation through the lungs. This blood, along with its associated vital pneuma, went via the arteries issuing from the heart to the brain. There the blood was further refined and charged with the final and highest form of psychic pneuma, which by passing through the ventricles of the brain to the nerves allowed thought and movement.

Although Galenic medicine correctly distinguished between veins and arteries, and used the observation and characterization of the pulse variations as an efficient diagnostic technique, it could not correctly explain the general concepts of the pulse generation. It was believed that both the heart and the arteries had their own pulsation and that they contracted simultaneously. The arterial pulse was the result of an active force generated in the arterial surface.

Instead of this complex system, Harvey established that the arteries and veins contain nothing but blood, that the blood constantly circulates in the body under the action of the heart, which functions as a pump, through two separate circuits: the lesser “circulation”—our “pulmonary circulation”—that flows from the right ventricle of the heart through the pulmonary arteries to the lungs and then returns to the left atrium of the heart through the pulmonary veins, and the “greater circulation—our “systemic circulation”—that flows from the left ventricle to the extremities via other arteries and from extremities back to the right atrium via the venous system.

Consequently, Harvey found that the heart beat was the result of the simultaneous contractions of the two auricles followed by those of the two ventricles, as long as the animal or the human being was alive. The source of the arterial pulse was in turn generated by the contraction of the left ventricle and consisted in a discontinuous and passive dilation of the arteries caused by the blood inflow. Harvey compared this dilation to the process of inflating a glove by blowing air into it. This image meant that dilation was not the result of a mere return to normal following a contraction of the heart or the arteries, or even a positive motion due to a certain dynamism proper to them, as it had been believed for centuries. It was more like the result of an increased pressure in a pipe. But it meant also that, in Harvey's opinion, if the heart and the arteries pulsated alternatively, the contraction of the heart prompting the dilation of the arteries, the pulse nevertheless was synchronous in the heart and the arteries—Ernst Heinrich Weber (1795-1878) discovered the delay in the transmission only in 1827.

Contrary to the usual teaching, it is clear from the facts, that the diastole of the arteries corresponds to the systole of the heart, and that the arteries are filled and distended by the blood forced into them by the contraction of the ventricles. The arteries are distended because they are filled like sacs, not because they expand like bellows. All the arteries of the body pulsate [pulsant] because of the same cause, the contraction of the left ventricle. Likewise the pulmonary artery pulsates. To illustrate how the beat in the arteries is due [arteriarum pulsu fieri] to the impulse of blood [ab impulsu sanguinis] from the left ventricle, one may blow into a glove, distending all the fingers at one and the same time, like the pulse [pulsum]. (Harvey, De motu cordis et sanguinis, 3, p. 47, trans. Chauncey D. Leake)

However, this radical shift in perspective had no direct impact on the concept of rhythm. Harvey used it to denote the alternating motions of the heart, which was a novelty compared to its traditional use qualifying the proportion between the motions of the arteries, but he did not change its definition. As it was customary in his time, he complemented rhythm with harmony, i.e. ratio based on perfect number. The motions of the auricles and the ventricles, he said, “take place consecutively but in such a manner that there is a kind of harmony and rhythm preserved between them.”

The motion of the heart is as follows: First, the auricle contracts, and this forces the abundant blood it contains as the cistern and reservoir of the veins, into the ventricle. This being filled, the heart raises itself, makes its fibers tense, contracts, and beats [omnes nervos tendit, contrahit ventriculos & pulsum facit]. By this beat [quo pulsu] it at once ejects into the arteries the blood received from the auricle; the right ventricle sending its blood to the lungs through the vessel called the vena arteriosa, but which in structure and function is an artery; the left ventricle sending its blood to the aorta, and to the rest of the body through the arteries. These two motions, one of the auricles, the other of the ventricles, [take place consecutively, but in such a manner that there is a kind of harmony and rhythm preserved between them] [seruata quasi harmonia & Rhythmo], so that only one movement may be apparent, especially in warm-blooded animals where it happens rapidly. (Harvey, De motu cordis et sanguinis, 5, p. 47, trans. Chauncey D. Leake, my mod.)

A little further down, Harvey faithfully endorsed Galen's categories concerning the pulse and, by the same token, his definition of rhythm: size, strength, speed, rhythm—ratio between systole and diastole—fullness, and regularity. The only difference was the new place he gave to frequency which was quite secondary to Galen and became, in his list, the third differentia (for Galen's list see vol. 1, p. 286).

The pulse corresponds to the tension of the heart [secundum cordis tentionem pariter pulsus] [in size, strength, frequency, speed, while still preserving rhythm, fullness, and regularity] [siunt maiores, vehementiores, frequentes, celeres, rythmum, & quantitatem, & ordinem feruantes]. Because of the motion of the blood it is reasonable to expect the heart beat and the dilatation of the arteries, even the more distant ones, to go together. It is like inflating a glove or bladder, or like in a drum or long beam, when the stroke and beat occur together, even at the extremities. (Harvey, De motu cordis et sanguinis, 3, p. 48, trans. Chauncey D. Leake, my mod.)

In the end, the main novelty was, ironically, the recess of the physiologist consideration for the rhythm issue itself, at least as it was defined at that time, which was alluded to only twice in the whole treatise. Clearly, Harvey was less interested in semiology than in anatomy. What counted most now was the circulation of blood in the “lesser” as well as the “greater” circulation. Therefore the pulse was still present in his mind, however it was not taken as a sign of the patient's state of health but in a mere mechanical and physical way: the alternation of the movements of a pump.

To support his view, he used in chapter 9 quantitative arguments. He measured the average weight of blood (and therefore volume) that can be pumped from the heart with each beat—in humans that was about two ounces, sometimes three—measured according to the Apothecaries or Troy weight that was in general use in Europe. He then estimated that if there were 2000 beats per half hour (66 beats/mn) the heart would pump and bring to the periphery 2000 beats x 2 oz. x 2 = 8000 oz. in an hour, or about 666 pounds of blood. Harvey deduced that such an amount of blood could not be produced or consumed in one hour; therefore, it had to circulate out in the arteries and back in the veins, over and over again, as long as the human was alive. This explains why not rhythm as ratio between dilation and contraction of the arteries but volume and frequency of the pulse beat were now at the center of Harvey's attention.

Thus, Harvey's personal direct contribution to rhythmology must not be overrated. It took some time before his discovery and the mechanical spirit it implied really changed the concept of rhythm. In spite of his own extraordinary discoveries, Harvey was actually remarkably conservative. In De generatione animalium – On Animal generation (1651), he explicitly rejected atomism and materialism. The works of nature, he claimed, contained “consummate art, and providence, and wisdom.” They had been constructed “for a certain purpose, and to some good and [...] by the Divine Architect” (quoted by Deming, 2012, p. 110). He was a devoted Christian and firmly believed in Aristotelian teleology. Nature did “nothing in vain,” and God had constructed the human body with a purposeful and intelligent design.

Then I reflected on the symmetry and size of the vessels entering and leaving the ventricles of the heart, for Nature, making nothing in vain, would not have given these vessels such relative greatness uselessly. (Harvey, De motu cordis et sanguinis, 8, p. 69-70, trans. Chauncey D. Leake)

Copernicus (1473-1543), Kepler (1571-1630) and Galileo (1564-1642) had overthrown the Ptolemical theory of the circular motion of the stars in the heavenly spheres, but Harvey seemed never to have heard of their discoveries. His inspiration for proposing circulation of the blood was the ancient Greek idea of circular motion as perfect. In On Generation and Corruption, Aristotle had written that “circular motion [...] is the only motion which is continuous” (2.10, 337a, trans. Harold H. Joachim). And Aristotle's conception of circular motion in turn was influenced by the earlier Pythagorean conception of circular motion as perfect (Deming, 2012, p. 110).

Harvey was also influenced by the astrological doctrine, which was most common in the Renaissance, of the mystical relationship between Macrocosm and Microcosm. The motion of blood was circular as the cycle of “air and rain” or the “circular motion of the superior bodies.”

[I surveyed my mass of evidence derived from vivisections] [...] [and] I began to think there was a sort of motion as in a circle. [...] This motion may be called circular in the way Aristotle says air and rain emulate the circular motion of the superior bodies. (Harvey, De motu cordis et sanguinis, 8, p. 70, trans. Chauncey D. Leake, my mod.)

Then invoking the traditional analogy between Macrocosm and Microcosm, he concluded that “the heart is the center of life, the sun of the Microcosm, as the sun itself might be called the heart of the world.”

The moist earth warmed by the sun gives off vapors, which, rising, are condensed to fall again moistening the earth. By this means things grow. So also tempests and meteors originate by a circular approach and recession of the sun. Thus it happens in the body by the movement of the blood, all parts are fed and warmed by the more perfect, more spirituous, hotter, and, I might say, more nutritive blood. But in these parts this blood is cooled, thickened, and loses its power, so that it returns to its source, the heart, the inner temple of the body, to recover its virtue. Here it regains its natural heat and fluidity, its power and vitality, and filled with spirits, is distributed again. All this depends on the motion and beat of the heart. So the heart is the center of life, the sun of the Microcosm, as the sun itself might be called the heart of the world. The blood is moved, invigorated, and kept from decaying by the power and pulse of the heart. It is that intimate shrine whose function is the nourishing and warming of the whole body, the basis and source of all life. (Harvey, De motu cordis et sanguinis, 8, p. 71, trans. Chauncey D. Leake)

Thus Harvey did not directly transform the concept of rhythm, which he maintained exactly as he found it in Galen, but he diminished its importance for medicine, while preparing two opposite mutations: on the one hand, in a mechanistic spirit, he introduced beat and frequency as subject of concern; on the other hand, he passed on the age-old comparison of the body movements with the natural periods or cycles.

Counting the Pulse – Towards Rhythm as Beat (Santorio and Galileo – 1602-1625)

Until recently, it was commonly believed that in his early years in Pisa, while studying medicine, Galileo (1564-1642) had invented an instrument, based on his discovery of the isochronicity of the pendulum swing, to allow the exact record of the pulse frequency (for this section, I used partly Bigotti, Taylor, Welsman, 2017).

New research has convincingly shown that this opinion was utterly mistaken and that the first technological application of the pendulum is due to Santorio Santori (1561-1636), who created what he called the Pulsilogium [lit. instrument that measures the pulse], possibly between 1590 and 1602, when the first mention of this new device was made in a treatise De pulsibus written by a colleague of Santorio in Padua. Santorio presented himself his invention in 1603 and in a more extended fashion—interestingly, given the role of Avicenna in the pulse theory in the Middle Ages—in his Commentaria in primam Fen primi libri Canonis Avicennae – Commentary to the Canon of Avicenna, published in Venice in 1625. According to the newest findings, “it probably constituted a source of inspiration for, rather than being an invention by Galileo, and sparked an entire path of experiments in 17^th century” (Bigotti, Taylor, Welsman, 2017, p. 30).

The Pulsilogium, in its simplest form, consisted of a weight—most probably a musket ball—swinging on the end of a cord; the rate of the swing was synchronized with the pulse by altering the length of the cord and, from this length, the rate of the pulse could be determined and compared with previous measures. As in Herophilus and Galen, the pulse of a patient could be compared to his or her own previous pulses and also to the pulse considered normal in his or her age group, gender, temperament.

The Pulsilogium [was] intended to measure “the quantity” or “the degree of distance” [quantitas/gradus recessus dimetiri] of the pulse rate, that is to say its variation in healthy or unhealthy conditions. Such distance [recessus] spans from a minimum to a maximum of frequency as well as intensity which, in reference to the latter, Santorio—and all Renaissance physicians—called “range of health” [latitudo sanitatis]. The Pulsilogium seems to have been used chiefly as a comparator: Santorio compared different segments of chord related to the increase or decrease of the pulse rate in terms of a rapport between degrees. He adopted the device as especially revealing of the variation of pulse frequency in fevers and other symptoms. [...] Whether by means of the Pulsilogium Santorio pursued an analysis of his patients grouping them by typology (melancholic, bilious, choleric, phlegmatic constitution) remains unclear, yet his constant use of the plural for referring to his subjects (sani/aegri homines) is possibly revealing of such an eventuality. (Bigotti, Taylor, Welsman, 2017, p. 33)

With this kind of light and simple instrument available, the attention of physicians began to shift from the size, speed, strength of the dilation, the proportion between dilation and contraction—which had defined for centuries the “rhythm”— the regularity or irregularity of their succession and the qualities of the arteries, that constituted the core of Galen's teaching, to a simpler measure: the rate of the artery beat. As a matter of fact, frequency had been taken into account as soon as Herophilus and was also an integral part of Galen's pulse lore but due to lack of precise timing device, general interest in quantification and possibility to elaborate a diagnostic from a fair number of other criteria, it was only secondary. Now, another course could be taken: due to its quantitative aspect and the new technical possibility to measure it easily, it began to counterbalance the other measures which were mostly qualitative and demanded a long training.

This shift in attention and practice initiated a shift in the meaning of the medical concept of rhythm. Whereas, since Antiquity, the latter had continuously denoted, in a poetic and musical way, the ratio between dilation and contraction of the arteries, it began to mean beat and frequency, number of beats per minute. This mutation resulted concomitantly in a kind of secularization of the meaning that had been superimposed upon the original sense during the Middle Ages. The regulation of motion analogous to the harmony between sounds of different pitches and similar to the circular movements of the celestial bodies could be now considered as a mere repetition of a beat having its own law, its own period or cycle, i.e. being regular.

When a few decades later (1654) Galileo's disciple Vincenzo Viviani (1622-1703) claimed that his master had invented the Pulsilogium shortly after his famous observation of the chandeliers swing in the Pisan church he was attending, he launched a nice piece of storytelling that we now know to be a legend. But he was capitalizing upon a number of real facts that are of great interest to rhythmology because they emblematize the passage from one era to another.

On the one hand, Galileo's father was a famous lutenist, composer, and music theorist, and he himself had become an accomplished lutenist and learned early from his musical practice to appreciate periodic or musical measure of time. In 1581, Galileo had embarked on a medical degree at the University of Pisa and he probably had a fair knowledge of the Galenic pulse lore, at least as it was taught in the Italian universities since the end of the Middle Ages in association with the belief in the “music of pulse.” Moreover, as it was usual in a time deprived of portable clock, Galileo had measured the swing of the chandeliers he was fascinated with against his own pulse, therefore considering the pulse as a human clock naturally related with the motion of the heavenly bodies. We know indeed that this was common practice and common belief by the example of Kepler who used to do and think the same during his astronomical observations.

But on the other hand, Galileo's groundbreaking work on pendulum motion had opened a entirely new scientific perspective that had made possible to overcome the general abstractions and qualitative approach of the medieval “natural philosophy” and substitute it with the empirically tested laws and quantification techniques of the modern “physics.”

Broadly speaking, most of the 16^th and 17^th century physicians and physiologists remained faithful to the Ancient definition of rhythm. It is obvious in Struthius and Mercado, but even Harvey, although he revolutionized physiology with his discovery of the blood circulation, maintained the old concept. However, the conditions for a significant conceptual shift were already slowly building. As soon as the mid-16^th century, Struthius and Mercado had already introduced in medicine a keen interest for timing the pulse. By 1610, whatever the respective role played by Santorio and Galileo in the invention of the Pulsilogium, it was sure that the new earthly and astronomical physics Galileo was helping to develop, along with the spread of its Mechanistic spirit, were bound to emphasize quantification and the concept of law in physiology and medicine, which meant, as far as rhythm was concerned, the progressive substitution of the notions of ratio, harmony, and cosmic period with those of beat, frequency and regularity.

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Rhythm from Beat to Wave – Modern Medicine (1707-1894)

Pascal Michon — 2017-12-14T16:30:00Z

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Previous chapter

From the early 18^th century, the medical concept of rhythm changed mainly for two reasons: the first was the Mechanistic perspective that was slowly penetrating medicine; the second was the use of new portable timing devices that brought more accuracy to observation. These new circumstances allowed the generalization of the concept of beat, its later transformation into that of wave, and their association with the concepts of frequency and regularity or periodicity, which was now taken in a new sense freed from its astrological connotations.

Rating the Pulse – Rhythm as Beat (from Floyer to Stokes – 1707-1878)

In the 17^th century, timing devices made spectacular progress. At the end of his life, around 1637, Galileo Galilei dictated to his son the plans for one of the first clock using a pendulum. Probably based on Galileo's idea, Christiaan Huygens created the first pendulum clock in 1656. Then, clockmakers' realization that only pendulums with small swings of a few degrees are isochronous motivated the invention of the anchor escapement around 1670, which increased further the accuracy of the clocks. The seconds pendulum—also called the Royal pendulum—0.994 m (39.1 in) long, in which each swing takes one second, became widely used in quality clocks after 1680. The increased precision resulting from these developments caused the minute hand, previously rare, to be added to clock faces beginning around 1690.

This new instrument, which was much more precise than previous time devices was to radically change the conditions of scientific experiment in astronomy and physics but also in physiology and medicine. It was not the only cause but it strongly participated in the shift from pulse rhythm as ratio of time-lengths to pulse rhythm as beat, frequency, and regularity.

Townsend has described how “the medical literature of the 18^th century is replete with pulse numerations” (Townsend, 1967). One of the first of a long series of physicians who emphasized the importance of rating the pulse was Sir John Floyer, who published The Physician's Pulse-Watch in 1707, and had a special “pulse-watch made, which ran 60 seconds,” to that aim. Although his watch was running too fast, he made numerous observations with it, noting the effects of age, sex, meals and exercise, and, remarkably, calculating the effect of variations in age, which was reviving some of the most fruitful intuitions of Herophilus (Fleming, 1997, p. 18).

After Floyer's introduction of the modern pulse count, physicians started to record their observations in their daily practice based on the number of pulse beats per minute. Bryan Robinson (1680-1754), an Irish physician, studied the pulse rate in different times during a day, and in people with different heights (1732). Jean-Baptiste Senac (1693-1770), physician to Louis XV, after studying one hundred soldiers, six feet in height, reported that the normal pulse rate ranged from 60 to 90 beats per minute. Other observations were also made such as the pulse rate to increase with age. In Observations Respecting the Pulse (1796), William Falconer (1744-1824) made numerous tables by which the degree of fever might be determined based on the proportion of the accelerated to the normal pulse (Ghasemzadeh & Zafari, 2011, p. 5).

By the mid-19^th century, thanks to the French Pierre-Charles Alexandre Louis (1787-1872), and the Irish Robert James Graves (1796-1853) and William Stokes (1804-1878), rating the pulse had become part of routine clinical practice in Europe (Fleming, 1997, p. 19).

In the 19^th century, the “pulse” itself retained most of its old sophisticated qualitative connotations, but due to the improvement of portable timing devices and the spreading of pulse rating practices, the concept of “rhythm” which was associated to it surreptitiously changed: it began to mean first frequency and regularity and only secondarily ratio.

This shift was recorded in the French Dictionnaire des sciences médicales (1820). In the article “Pouls,” its author, Serrurier, differentiated first between the “strength and intensity of each pulsation” and the rhythm strikingly defined as “mode of the pulsations.”

The pulse, in the natural state, is equally soft, supple, free, not frequent, not slow, vigorous, without seeming to make any sort of effort. But because of the countless differences which nature presents, in the various diseases, with respect to the regularity of the pulse, we can reduce them, according to M. Double, to two general points of view which cover all nuances and modifications.

The strength or intensity of the pulsations.

The rhythm or mode of these pulsations.

In the first case, the modifications derive from each of the pulsations considered in isolation.

In the second case, they emerge from the comparison of the pulsations between them, and in a given time. (Dictionnaire des sciences médicales, “Pouls,” 1820, p. 443, my trans.)

A few pages below, Serrurier completed the definition. The “mode of the pulsations” itself comprised “frequency,” i.e. number of beats per minute, and “regularity,” in which he included regularity in time, but also in strength and speed.

The observations concerning the change of the pulse rhythm in the affections which we have just pointed out demonstrate the value of the two general points of view which we must always have in mind in all diseases of the organs: the strength or intensity of the pulsations, and the rhythm or mode of these pulsations. By considering each of these pulsations in isolation, we can guess from where their modifications can derive, and we assure our diagnosis; likewise, by comparing the pulsations between them, and in a given time, we can establish, according to their frequency, their regularity and their irregularity, their strength or their weakness, their vivacity or their slowness, a prognosis all the more true that we make coincide the signs drawn from the pulse with those exhibited by the whole sick individual. (Dictionnaire des sciences médicales, “Pouls,” 1820, p. 445-446, my trans.)

Two decades later, the Belgian Répertoire général des sciences médicales au XIXe siècle (1843) was even more concise. Normal rhythm, although still defined as ratio, included only two aspects: regularity and frequency.

2. Sorts of pulse defined according to the characters of the rhythm. These sorts of pulse, based on the succession or the ratio of the pulsations between them, present sometimes regular beats and sometimes irregular beats [tantôt des battements réguliers et tantôt des battements irréguliers]. We include into the first division the more or less frequent pulse, and into the second the unequal and intermittent pulse. Those are the characters of the pulse that are the easiest to notice. (Répertoire général des sciences médicales au XIXe siècle, “Pouls,” 1843, p. 332)

Timing the Pulse – Rhythm as Beat (Marquet – 1747)

In 1747 François-Nicolas Marquet (1687-1759) published a Nouvelle Méthode facile et curieuse pour apprendre par les notes de musique à connaître le Pouls de l'Homme, & les différens changemens qui lui arrivent, depuis la naissance jusqu'à la Mort – An Easy and Curious New Method of Knowing by Musical Notes the Pulse of the Man, & the Various Transformations which Occur from Birth to Death. A second edition was published in 1769 (this the one I used; on Marquet see, Dos Santos Costa, 2008; Pesic, 2016; Pennuto, 2017).

As Struthius and Mercado two centuries before, Marquet followed Galen on many points while proposing to use the musical notation to help the physician during his visits to note and classify the different varieties of pulse. But in the meantime, both physiology and theory of music had changed.

Like his predecessors, Marquet was fond of Galenic concepts. Although he rejected some of the most bizarre pulses, he recognized the pulsus dicrotus or double, caprizans, vermicans and formicans, the deep or superficial pulses. To those, he associated explanations relating pulse irregularities to excess of sulfur, salt or serum, which very soon excited the irony of Menuret de Chambaud, the author of the article “Pouls” in Diderot's and d'Alembert's Encyclopédie.

The abundant sulphurous part produces a great and vehement pulse, the saline an intermittent pulse, the serous a small, weak, and late pulse, the globulous a frequent pulse. And when these causes are united and act together on the pulse, they result in this kind of pulse that is called convulsive. The intercadent, escaped or intermittent pulse owes its origin to air bubbles which enter the blood, and which make, in the places where they are, the dilation of the artery imperceptible; from that, one may judge of the author's ideas, genius, and light. (Menuret de Chambaud, “Pouls,” Encyclopédie, 1756)

But his approach was, at the same time, deeply influenced by the modern spirit of precision and quantification. What he presented as a “facile et curieuse” method was actually inspired by a strong concern for updating the qualitative technique of the ancient pulse lore and making it meet the modern mechanistic standard.

Marquet defined the pulse according to the ultimate Harveyan physiology. The pulse felt by the physician on the wrist of his patient was “a beating of the heart and arteries” which made the blood circulate “from the center to the circumference and from the circumference to the center.”

The pulse is a beating [le pouls est un battement] of the heart and arteries, which makes the blood flow from the center to the circumference and from the circumference to the center. The first movement that occurs in the heart of the fetus produces the beat [le battement], which continues until death. (Nouvelle méthode..., 1747-1769, p. 9-10, my trans.)

In his introduction, Marquet explained that this beat was the result of “alternative” motions of the heart and arteries but he still believed, as indeed Harvey, that the beats that were felt by the physician were simultaneous.

The beating of the heart [le battement du cœur] and the arteries is alternative [alternatif], it is called systole and diastole; the systole is the contraction of the heart and arteries, and the diastole their dilatation. At the same time that the heart contracts, the arteries dilate to receive the blood, and carry it to the extremities of the body, where it is then to be carried to the heart through the veins. [...] Therefore, one must feel the beating of the heart and arteries, at the same time. (Nouvelle méthode..., 1747-1769, p. 10-12, my trans.)

Marquet used a hydraulic metaphor, comparing the human body to a “hydraulic machine,” but surprisingly he did not present the heart as a pump but held it instead similar to “the pendulum in a watch, or in a clock.” The heart was like a timing device and therefore the pulse like a regular beat.

The heart holds the same rank and performs the same functions in man, as the pendulum in a watch, or in a clock; the veins and arteries serves as wheels and the nerves are the ropes which make the hydraulic machine act. (Nouvelle méthode..., 1747-1769, p. 1, my trans.)

Marquet retained the old Galenic concept of “eurhythm” but he changed greatly its definition as much as those of its various deviations. Whereas the Pneumatics and Galen in Antiquity, as well as Struthius and Mercado in the 16^th century, differentiated between “eurhythm,” “pararhythm,” “heterorhythm,” “echrhythm,” and “arhythmia” according to a series of age groups which were respectively characterized by a typical ratio—1/1; 2/1; 2/2; 1/2 or ½/½; 1/1; 2/2; 4/4—he proposed to classify them according to three criteria which were based on a very different logic: regularity, frequency and degree of complexity.

Health depended on a well “regulated” functioning of the human machine; illnesses occurred when the machine was deregulated.

So long the movement of the heart and the arteries is regulated [est réglé], the human body remains in perfect health, but as soon as this movement is disturbed by some accident, the health is altered by an infinity of diseases. (Nouvelle méthode..., 1747-1769, p. 1-2, my trans.)

Whereas for Struthius the “natural rhythm,” which served as benchmark for measuring the deviation of the pulse, was the “equal rhythm” characterized by a n/n ratio, it was now qualified as “natural, regulated and tempered pulse” and defined first by its regularity—all the pulsations were supposed to have the same strength, the same cadence, and the same interval of five times that “one notices between two pulsations or from a beat to the next”—and also by its number of beats per minute—as for Kepler and probably for the same astrological reason, it was supposed to beat sixty times in a minute (p. 32). Marquet did not provide more explanation for this particular number. Strangely enough, given that the pulse comprised five times, the natural pulse usually emulated the tempo of a minuet, or a dance in ³/₄ time signature, that was to be sung or remembered while one took the pulse.

The natural, regulated and tempered pulse [Le pouls naturel, réglé et tempéré] is one which has the same force, the same cadence [cadence], or the same interval, and which has five times [cinq temps] between each beat or pulsation [entre chaque battement ou pulsation]. It is usually similar to the cadence of the minuet in movement [la cadence du menuet en mouvement], it also imitates the second of a well adjusted/regulated clock [une pendule bien réglée]. When it is calm and temperate, it is about sixty pulsations [soixante cadences] or so, and runs sixty minuet cadences [parcourt soixante cadences de menuet] in a minute, and 3600 in the lapse of an hour. (Nouvelle méthode..., 1747-1769, p. 34-35, my trans.)

Naturally, as a good Galenist, Marquet recognized that some people, depending on their specific temperament, their gender or their age, had a different natural pulse, but the only significant difference he mentioned was that the latter run faster or slower.

There are nevertheless certain individuals endowed with a lively and bilious temperament, whose pulse, though natural, increases in speed by one degree, or one time in each pulsation [dans chaque pulsation]; others, on the contrary, of a phlegmatic or melancholic temperament, whose blood is so thick and its circulation so slow, that one can count, especially in the morning, up to six times between each beat [jusqu'à six temps entre chaque battement]. (Nouvelle méthode..., 1747-1769, p. 35-36, my trans.)

The pulse that deviated from this norm “by strength or movement and often by both” was “unnatural” and could vary in many ways (p. 40). These differences could be “simple or composite.” The simple pulse was divided into “great and small, equal or unequal, deep or superficial, hard or soft, etc.”; the composite pulse instead could be “subdivided ad infinitum” (p. 41). All in all, Marquet counted no less than twenty-four different kinds of pulse, classified by their degree of complexity and presented with each corresponding pathophysiology.

To legitimate the use of musical notation to describe and assess these different pulses, Marquet referred, as expected, to the traditional authorities of Avicenna, Savonarola, Saxon, Fernel, and naturally Herophilus—he did not mention Struthius nor Mercado (p. 4-5). But his own argumentation was based on the modern concern for precise quantification. Marquet compared his use of musical notation to the two main scientific analytical systems: the series of numbers and that of letters. Notes were mere equivalents of numbers and letters.

There is not more oddness in describing [peindre] the pulse with notes than in describing [peindre] the sounds of music with the very same notes; numbers with figures [les nombres avec les chiffres]; and finally, words with the letters of the alphabet. (Nouvelle méthode..., 1747-1769, p. 4, my trans.)

Moreover, since Struthius' and Mercado's time, the theory of music and the notation had changed. The ancient mensural notation system, which had been used for European vocal polyphonic music from the later part of the 13^th century until about 1600, had been replaced by the modern notation system, which now featured clef, time signature and bars or measures, and little by little directions for tempo and dynamics. This new system provided a tool for timing music associating versatility and precision thanks to its remarkable capacity to accurately record the continuous changes in the duration of notes within the reliable time frame provided by the regular succession of bars or measures.

It is necessary that the one who wants to learn these principles have at least some superficial knowledge of music, so that, by beating the regulated measure [battant la mesure réglée], he gets used to know the right cadence of the pulse [la juste cadence du pouls] by comparing it to that of the music. (Nouvelle méthode..., 1747-1769, p. 33-34, my trans.)

The “natural” pulse—that which was “regulated and temperate”—was noted by quarter notes placed between two parallel lines, and which were separated by five small vertical lines that represented the five times between two successive pulsations. Every pulsation, i.e. every quarter note, was placed next to a vertical larger line that corresponded to each bar or measure of the minuet which was noted below.

The other durations of each pulsation were noted accordingly: the great or full pulsation, frequent in pleurisy, pneumonia and hemorrhage, with half notes; the small pulsation frequent in weakness, cachexia, slow fever, with eighth notes; and the vermicular pulsation, frequent in fatal disease, with sixteenth notes (p. 30-31 – see table n° 11).

Marquet noted also the volume and strength of the pulse with the location of the notes on the staff : if the note was placed below the first line, the pulse was said to be concentrated; on the first line, it was said deep; between the two lines, it was natural; on the second line it was high and above the second line it was superficial.

The frequency was noted by a greater or lesser number of times between each pulsation, for instance 2 times for a fast pulse and 6 times for a slow pulse.

Finally, in addition to the duration, the strength, and the frequency of the beat, Marquet noted its regularity and order according to a scale of growing complexity. If the note was on the first time of the measure, the pulse was normal. If instead it was noted on another of the five spaces representing the pulse times, the pulse was “irregular or unequal in movement.”

If we count more or less of these spaces between each beat [entre chaque battement], the pulse will be irregular or unequal in movement [irrégulier ou inégal en mouvement]; if the note is not placed between the two parallel lines, it will be unnatural in its strength. (Nouvelle méthode..., 1747-1769, p. 32, my trans.)

One just have to look at the scores representing the goat-like pulse (caprisant) and the convulsive pulse to realize how precise this method was.

Thanks to this system, Marquet could note both the variation in strength, duration, frequency of one pulsation, and the frequency, regularity and order of a series of pulsations. The only important measure he did not provide, except by referring to the physician's memory of a well known dance, was the tempo that allowed to measure the frequency, which was not fixed in the 18^th century. In his famous book, On Playing the Flute (1752), Quantz himself relied on “the pulse beat at the hand of a healthy person [...] approximately 80 beats per minute” as his time standard. Along with Galileo and Kepler who measured observation time with their own pulse, Quantz used the pulse, not a clock, to prescribe tempi (Pesic, 2013, p. 1).

In the last two examples that were given—the “goat-like” and the “convulsive” pulses (fig. n° 22 and 23)—it became clear that the pulse rhythm was not any longer composed of simple ratios between dilation and contraction of the arteries but of all these measures concerning the pulsations (i.e. only the dilations) either alone and/or observed in series. Although it still was a discrete system of notation, Marquet anticipated, without any mechanical instrument, the oscillating graphs that were to become common in the 19^th century.

Feeling and Hearing the Pulse – Rhythm as Sign (from Solano to Laennec– 1731-1819)

During the 18^th century, quantitative and qualitative diagnosis methods remained firmly at odds with each other. Physicians fond of Mechanism and mathematical measure rejected the old Galenic pulse lore that was, in their opinion, too long and difficult to learn, too complicated to implement, and that could only deliver vague guesses for diagnosis as much as prognosis. In 1772, for instance, William Heberden (1710-1801) declared that “such minute distinctions of the several pulses exist chiefly in the imagination of the makers” (quoted by Fleming, 1997, p. 21). These physicians substituted humoral view, qualitative observation, and, as far as rhythm was concerned, ratio between dilation and contraction, with an overall mechanistic perspective, quantification, and frequency of the pulse beat.

But others, who according to Menuret's testimony were a small if active minority, rejected the Mechanistic view on behalf either of a new version of the old humoral physiopathology or of a more recent Vitalism. These physicians thought that the Galenic pulse lore was still of great help to medicine, although it had to be deeply renovated. All of them supported qualitative observation, and paid great attention to the various aspects of the pulse rhythm that were considered as signs to be interpreted.

This reaction against Mechanism began with a Spaniard, Francisco Solano de Luque, nicknamed “el pulsista” (1684-1738). In his Lapis Lydos Appollinis. Methodo segura y mas util asi para conocer como para curar las enfermedades agudas – The Touchstone of Appolo. Secure and Most Useful Method to Know How to Cure the Acute Diseases and his Observaciones sobre el pulso, published respectively in 1731 and 1787, Solano revived the ancient doctrine of the critical pulse. The meticulous observation and interpretation of the pulse could help the physician, Solano claimed, to determine the course of the disease and especially the moments of crisis which could be fatal or, on the contrary, bring relief to the patient by triggering the critical excreting of morbid humors.

A few years later, James Nihell, an Irish physician practicing in Spain, became interested in Solano's teaching on crisis and pulse rhythm. He popularized it in 1741 in his own Nuevas y raras observaciones, para prognosticar las crises por el pulso sin alguna dependencia de las señales criticas de los antiguos – New and Extraordinary Observations Concerning the Prediction of Various Crisis by the Pulse.

Nihell's treatise on the pulse was followed by several others, which drew on Solano and Nihell, for example in 1753 by Malcolm Flemyng (ca. 1700-1764): A physiological comment on Solano's prognostics from the pulse, and in 1758 by Daniel Cox (dates unknown): Observations on the intermitting pulse, as prognosticating, in acute diseases, according to Dr. Solano, a critical diarrhoea – or, as indicating the use of purging remedies, which had height editions in English and seventeen in French between 1760 and 1785 (cf. worldcat.org).

These attempts at defending, until late in the 18^th century, the old humoral physiopathology and the Galenic pulse lore, was certainly quite reactionary from a medical viewpoint, but it must also be related with the development of the modern theory of semiotics at the hands of Locke and his successors. Moreover, the new emphasis on the Hippocratic and Galenic concept of crisis was a significant rhythmological event because this concept was, as we will see, eventually transferred from medicine to economy by Clément Juglar. The concept of crisis, as a possibly destructive as much as relieving event was then integrated into the web of concepts related to rhythm, while being considered as periodic, which was not the case in medicine.

Another important contribution to the qualitative and semiotic approach to the pulse was that of Théophile de Bordeu (1722-1776) who was physician to the Countess du Barry and a close friend of Diderot. In his Recherches sur le Pouls par rapport aux crises – Investigations on Pulse in Relation with Crises published in 1756, he used Solano's prognosis work and crossed it with the diagnosis theory of organic pulses of Galen and even the Chinese. Changes in the pulse, particularly in its rhythm, were not only announcing future crises, but they were also indicating the state of the organs. Rhythms were signs of particular disturbances in the “animal economy.”

Driven by his semiotic search for signs, Bordeu developed new diagnosis technique. Pulse recognition depended not only on the tactile abilities of the physician but also on his skills in auditory perception. Physicians were required to memorize various acoustical patterns, then match them to the “live” pulse pattern of the patient perceived during observation. The introduction of sound in medicine, which had hitherto been concerned mainly with sight and touch, opened up entirely new clinical practices that were eventually to become the basis of modern auscultation (for more details see Sykes, 2012 and 2015).

The debate between Mechanistic and Semiotic pulse theories is perfectly staged in the article “Pulse” written by Jean-Joseph Menuret de Chambaud (1739-1815) in Diderot's and d'Alembert's Encyclopédie (1765, vol. 13, p. 205-240).

I reproduce in this paragraph a part of the enlightening biography established by Kafker & Kafker (1988). Menuret got the doctorate in medicine in 1757 at the Montpellier Faculty of Medicine. Some time afterwards he continued his medical investigations in Paris, where he worked with Théophile de Bordeu and studied chemistry with Guillaume-François Rouelle. Menuret was recruited for the Encyclopédie by one of Rouelle's disciples, Venel, who was unable to manage all his commitments to the work. Strongly influenced by Bordeu, Menuret championed in his articles many of the leading ideas of the Vitalist school of Montpellier; he challenged the Mechanism of Hermann Boerhaave, the Animism of Georg Ernst Stahl, and the Chemical theories of Thomas Willis. However, in the article “Influence ou influx des astres,” he wrote of the moon's and sun's effects on health.

In his article, Menuret presented one after the other the Ancient Herophilean-Galenic pulse lore; the new Mechanistic conception of pulse; Marquet's and Bordeu's most recent contributions; finally, the Chinese pulse lore as it had been recently discovered by missionaries.

Menuret's opinion was very close to Bordeu's. He criticized the exaggerate importance given to Harvey's discovery, the disinterest of the Mechanicist physicians for the pulse as “sign,” the abstract debate about its “strength and causes,” and contrasted it with an attention to its variations and their “significations.” As for Bordeu, the Chinese had developed a full semiotic theory concerning the pulse that was worth inquiring because it was close, in spirit if not in fact, to that of the Vitalist school.

Bellini is one of the first and most famous authors who considered the pulse mechanically. Hoffman followed his system and claimed to prove, in a particular dissertation, that the pulse must be subject to the rules of mechanics. Boerhaave and all his followers, all the physicians who have embraced the common theory [la théorie vulgaire], based on the ill-conceived and too generalized famous blood circulation, and on the insufficient laws of inorganic mechanics; all these physicians, I say, who are still the most numerous and almost dominant in the schools, have adopted their opinions on the pulse. They make little use of this sign, examine it without attention, and draw little and very uncertain knowledge from it. But on the other hand they make it an important object of their dissertations, their arguments and their calculations. They submit it to mathematical analysis, and are much more concerned in determining geometrically its strength and causes, than in correctly grasping its differences, and in estimating their meanings. (Menuret de Chambaud. “Pouls,” Encyclopédie, 1765, vol. 13, p. 215, my trans.)

Bordeu was followed in 1767 by Henri Fouquet (1727-1806) who published in 1767 his Essai sur le Pouls, par rapport aux affections des principaux organes, avec des figures qui représentent les caractères du Pouls, dans ces affections – Essay on Pulse in Relation with the Affections of the Main Organs, with Figures Representing the Characters of the Pulse in these Affections. Fouquet combined Solano's critical pulses and Bordeu's organic pulses and illustrated them with drawings. He too was committed to touch and hearing, and rejected both Marquet's musical notation and Mechanistic pulse rating, which he ironically called mere “pretense,” “sphygmometers”—a name that was to become very successful in the 19^th century—and “small physical curiosities.” Semiotics was much more useful to medicine than arithmetics and physics.

It may be judged now, by all that has hitherto been said of the true and intrinsic character of the pulse of the organs, of the importance which must be given to the system of Herophilus, which pretends to subject the rhythms of the pulse to the rules of music, and other similar systems advanced by some Modern [Marquet's New Method was explicitly cited].

Finally, one can draw from it some esteem for these sphygmometers [sic] and all these other small physical curiosities, with which the Mechanicists have entertained for so long the rational medicine, although they could not embarrass/thwart [embarrasser] with it the practical medicine. (Fouquet, Essai sur le pouls..., ed. 1818, p.77, my trans.)

At the beginning of the 19^th century, René Laennec revolutionized diagnosis by introducing the stethoscope and auscultation. In 1819, he published a long treatise De l'auscultation médiate ou traité du diagnostic des maladies des poumons et du cœur, fondé principalement sur ce nouveau moyen d'exploration – On Mediated Auscultation or Treatise on the Diagnosis of Lungs and Heart Diseases Mainly Based on this New Exploration Means, where he emphasized the need for a thourough observation of the heart rhythm.

595. The motions of the heart must be examined in four principal respects: 1. the extent to which they can be heard by means of the cylinder [the stethoscope]; 2. the shock or impulse strength of the organ; 3. the nature and intensity of the sound that it makes; 4. the rhythm according to which its various parts contract. (Laennec, De l'auscultation médiate..., vol. 2, p. 196, my trans.)

Laennec defined rhythm as the order and ratio between “the contractions of the various parts of the heart,” i.e. not any longer between the motions of the arteries but still as ratio and order.

635. By rhythm I mean the order of the contractions of the various parts of the heart as they are heard and felt by the cylinder, their respective duration, their succession, and, in general, their relation to each other. (Laennec, De l'auscultation médiate..., vol. 2, p. 215-216, my trans.)

According to his findings, this order was composed of three successive, dissimilar and periodic motions: first, the contraction of the auricles for a quarter of the full cycle; then a rest for another quarter; finally, the contraction of the ventricles for the remaining half.

640. The duration of the contractions of the auricles and ventricles seems to be determined more or less in the following manner. In the total duration of the time in which the successive contractions of the various parts of the heart are performed, a third or more, or even a quarter, is used by the systole of the auricles; a quarter, or a little less, by absolute rest, and half or so by systole of ventricles. (Laennec, De l'auscultation médiate..., vol. 2, p. 218, my trans.)

Healthy men enjoyed a “regular rhythm” even if the latter could vary or be disturbed in many ways.

I will, consequently, describe in their successive order the phenomena which the heartbeat of a healthy man provoke in the ear, a man whose heart has the most favorable proportions for the free exercise of all functions. (Laennec, De l'auscultation médiate..., vol. 2, p. 216, my trans.)

653 [...] In many circumstances, which are not always illnesses or even serious ailments, this rhythm is subject to various anomalies: physicians ordinarily reduce them to three principal species, palpitations, irregularities, and intermittency. (Laennec, De l'auscultation médiate..., vol. 2, p. 226, my trans.)

In Laennec's vocabulary, rhythm was still different from beat and frequency.

On May 22, the symptoms were still the same, without increase or decrease. The face was continuously red, the skin moist, the pulse quite natural, either in terms of frequency, or of development and rhythm. (Laennec, De l'auscultation médiate..., vol. 2, p. 413, my trans.)

Tracing the pulse – Rhythm as Wave (from Hales to Ewart – 1733-1894)

Qualitative and quantitative methods for measuring the pulse were not to remain definitively at odds though. Substantial progresses were made in mathematics, fluid mechanics and measuring devices which enabled the two methods to merge.

The mathematical language in which Nature's book was written, as Galileo put it, rapidly became very sophisticated. As soon as the end of the 17^th century—between 1684 and 1704—Newton and Leibniz, resuming without knowing it with some ancient rhuthmic Archimedean concepts (see, vol. 1, chap. 5), published essays which leaped from geometry, the study of shape, and algebra, the study of the generalizations of arithmetic operations, to calculus and the study of continuous change and variation.

Then fluid mechanics could penetrate physiology. In his famous treatise on the circulation of blood, Harvey had applied the laws of mechanics to the circulation of blood in arteries and veins, which was considered as that of any other liquid, varying in consistency and circulating under varying pressure in various kinds of pipes. The heart was only a pump and the pulse the result of the blood being propelled under a certain pressure and with a certain velocity into the arteries then in the veins. But Harvey still lacked mathematical instruments to give a full account of the blood dynamics.

The first studies on arterial haemodynamics were developed by Stephen Hales (1677-1746) in a series of papers entitled Statical Essays: containing Haemastaticks (1733). In Experiment 3, for instance, he discussed the velocity at which blood was ejected from the heart of a 10-year-old mare and how it was altered by the elasticity of the arteries.

The systole of the ventricle during which that quantity of blood is propelled, being estimated to be done in one third of the space of time between each pulse, the velocity of the blood during each systole will be thrice as much, at the rate of 5211 feet, that is, 0.98 of a mile in an hour, or 86.85 feet in a minute. Now this velocity is only the velocity of the blood at its first entering into the aorta, in the time of the systole; in consequence of which the blood in the arteries, being forcibly propelled forward, with an accelerated impetus, thereby dilates the canal of the arteries, which begin again to contract at the instant the systole ceases: by which curious artifice of nature, the blood is carried on in the finer capillaries, with an almost even tenor of velocity, in the same manner as the spouting water of some fire-engines, is contrived to flow with a more even velocity, notwithstanding the alternate systoles and diastoles of the rising and falling embolus or force. (Hales, Statical Essays: containing Haemastaticks, 1733, quoted by Parker, 2009)

In 1755 Leonhard Euler (1707-1783) submitted an essay Principia pro motu sanguinis per arterias determinando – On the Flow of Blood in the Arteries as an entry in a prize competition set by the Academy of Sciences in Dijon. For this paragraph and the next, I used Parker (2009) and Tijsseling & Anderson (2008). In it he set out the one-dimensional equations of conservation of mass and momentum in a distensible tube. In his notation

where s is the cross-sectional area, v is the average velocity, p is pressure, g is the density of blood, t is time and z is the axial distance. However, he was quite unsuccessful in proposing a formula that could simply show the relationship between the mechanical forces and the dynamic measures of the arterial pulse wave. He posited some rather unrealistic constitutive laws (tube laws) for arteries and unsuccessfully tried to solve the equations as he had done for rigid tubes by reducing them to a single equation that could be solved by integration (Parker, 2009).

In 1808, Thomas Young (1773-1829) published a paper entitled “Hydraulic Investigations, subservient to an intended Croonian Lecture on the Motion of the Blood.” In this paper he established the correct formula for the wave speed in an artery but gave no derivation of it. The celerity (c) of a pressure wave, propagating in an incompressible liquid of mass density ρ, contained in an elastic tube with Young's modulus E and where e/D is the ratio of wall thickness to tube diameter, was determined as

In short, Hales', Euler's and Young's studies, as well as others of the same type, showed that the pulse was not to be measured only by its frequency and regularity but also by the volume, the pressure, and the speed of the blood waves that circulated in the arteries. But it took again some time before scientists invented devices capable to measure and record those variables.

The first blood pressure measuring device was created in 1834 by Jules Hérisson who called it “Sphygmomètre – Pulse meter,” probably without knowing of Fouquet's mockery. Hérisson described his new device in a memoir presented to the Institute of France and published in English the very next year: The sphygmometer, an instrument which renders the action of the arteries apparent to the eye; the utility of this instrument in the study of disease, researches on the affections of the heart, and on the proper means of discriminating them considered. This instrument was composed of a graduated glass tube containing mercury with a semiglobular steel ball at one end. By placing the semiglobular end over an artery, the action of the vessel and the force of its impulse could be shown and measured (Ghasemzadeh & Zafari, 2011, p. 6).

Hérisson's sphygomètre allowed to measure the arterial pressure but it lacked a recording device. This shortcoming prompted Carl Friedrich Ludwig to create a few years later the Kymograph (1847) or “Wave-writer,” which was a revolving drum wrapped with a sheet of paper on which a stylus moved back and forth recording perceived changes of pressure. Karl von Vierordt adapted it to the measure of the pulse and created the Sphymograph in 1854 which was further improved by Etienne-Jules Marey in 1859.

“Polygraphe à bande de papier sans fin relié à un explorateur à coquille pour inscrire la pulsation du cœur ” – Etienne-Jules Marey, La circulation du sang ..., 1881, fig. 66, p. 150.

“Sphymographe direct” – Etienne-Jules Marey, La circulation du sang ..., 1881, fig. 109, p. 214.

As a result of the progress made in calculus, physiology of blood circulation, and measure and record technology, the pulse began to be assimilated to a wave in two manners:

First, the blood circulated in the arteries under the pressure of successive waves.

The heart contracts: thereby a wave of increased pressure is set up in the arterial stream; this we call the pulse-wave. (W.M. Ewart, The Pulse Sensations: A Study in Tactile Sphygmology, 1894, p. 18)

Second—and this was to prove more significant in term of conceptual change—the measures of the volume, the pressure, or the speed of the blood in the heart or the arteries were translated by the recording devices into oscillating curves which motivated Ludwig to call his invention the Kymograph or Wave-writer.

In 1863, Marey published a long study on blood circulation which recapitulated his findings made with the Sphygmographe: Physiologie médicale de la circulation du sang, basée sur l'étude graphique des mouvements du cœur et du pouls artériel avec application aux maladies de l'appareil circulatoire – Medical Physiology of Blood Circulation. Very soon the studies in haemodynamics multiplied. In 1875, William Broadbent (1835-1907) published in The Lancet “A clinical lecture on the pulse: its diagnostic, prognostic and therapeutic indications” (vol. 106, no 2717, p. 441-443). Starting from 1880 there was a wave of detailed studies on haemodynamics. Marey published La circulation du sang à l'état physiologique et dans les maladies – Blood Circulation in Physiological State and in Diseases in 1881 and Broadbent his famous essay The Pulse in 1890.

In all those texts, one can observe a new change in the meaning of the term rhythm as used by physicians. Whereas it had meant for centuries ratio between durations, then little by little beat and frequency, it now denoted the succession of the blood waves shown to the readers by spectacular figures.

In 1863, Marey explained what he was aiming at when creating the Sphygmographe. After mentioning the measure of “frequency,” “regularity,” and “intensity,” which were already regular features in medical pulse rating, he stressed with italics the “specific form” of the pulsations of an artery.

The goal we have pursued in the construction of our Sphygmograph is: to record the pulsations of an artery, not only with their frequency, regularity and relative intensity, but with the specific form of each one of them. (Etienne-Jules Marey, Physiologie médicale..., p. 183, my trans.)

His books and those of his colleagues were full of figures representing the pulse wave of various animals and human beings of different gender, age and health state, under various conditions such as heat, cold, pressure, psychological stress, toxic substances, etc. Figure 22 in La Circulation du sang, for instance, presented the readers with “the effects of heat (line C) and cold (line F) on the rhythm of a frog heart.”

Etienne-Jules Marey, La circulation du sang..., 1881, fig. 22, p. 47.

In Germany, important research activities were developed by physiologists such as Johannes von Kries (1853-1928), who published in 1887 an important essay on the “Wellenbewegung des Blutes – blood wave movement” and where one could find the same kind of graphics representing the pulse wave in different parts of the limbs (thigh, arm, in different times of the day).

Johannes A. von Kries, “Ueber ein neues Verfahren zur Beobachtung der Wellenbewegung des Blutes.” Archiv für Physiologie, 1887, p. 254-284.

A thorough study of Marey's uses of the term rhythm in his 1881 book on pulse shows that he took rhythm first as synonymous with recurring beat, as it had become customary in his time, but also, with succession of graphic waves—as in the previous figures—and by a kind of metonymy, with the very frequency and regularity of these beats and waves which, properly speaking, were only two of their characteristics.

One sees, for instance, the invasive importance given to frequency from the way Marey clarified an expression such as “disturbance of the [heart] rhythm” by phrases like “acceleration,” “slowdown,” and “complete stop of its beats.”

Often, by detaching the heart of an animal and by moistening it with a toxic solution, one observes a disturbance in its rhythm [un trouble de son rythme], a slowing down or an acceleration, and finally a complete stop of its beats [un arrêt complet de ses battements]. (Etienne-Jules Marey, La circulation du sang..., p. 492, my trans.)

Marey's implicit equating of rhythm to frequency particularly showed through the recurrence of phrases like “acceleration of the rhythm,” which kept returning under his pen (p. 33, 45, 46, 47, 48, 50, 56, 59, 60, 61, 64, 284, 332, 337, 338, 340, 344, 403, 473, 478 n. 1, 484, 487, 488, 493, 597) or the opposite “slowdown of the rhythm” (p. 29, 48, 186, 340, 364, 399, 404, 468, 470, 472, 478, 482, 514). In passing, he also mentioned the “slowdown of respiratory rhythm” (p. 461).

The assimilation of rhythm to regularity was also implicit in Marey's frequent use of the phrase “regularity of the rhythm” and, even more frequently, “irregularity of (or in) the rhythm” (p. 155, 156, 292, 462, 463, 554, 621, 622, 668, 689, 690).

In both cases, these uses were so frequent that the term that was supposed to be qualified (rhythm) was, so to say, contaminated by and made equivalent with that that was qualifying it (frequency or regularity). As a matter of fact, Marey, sometimes, significantly used phrases such as “acceleration of the heart frequency” (p. 78) or “acceleration of the heart beat” (p. 336), instead of the expected “acceleration of the rhythm,” as if the terms “rhythm,” “frequency,” and “beat” were interchangeable. He also coined, by swaping “rhythm” and “irregularity,” remarkable new phrases such as “the periodic irregularity of the rhythm” (p. 222, 294, 621), “the rhythm of the irregularity” (p. 723) or, in the very last page of the book, “the rhythmic irregularities which are so frequent in old people” (p. 724 – according to a phenomena already described by Galen in De pulsibus ad Tirones, 6). Irregularity itself could be periodic or rhythmic, i.e. regular. Rhythm was then equated with regularity.

In old age patients, irregularities in the rhythm of the heartbeat sometimes occur [...]. In some cases, the irregularity is not complete, because one observes the return, from time to time, of groups of pulsations which are unequal between them, but which reproduce the same rhythm in a periodic way [le même rhythme de façon périodique]. [...] Figure 127 was collected from an old man in whom we observed the following rhythm [le rhythme suivant]. A suspension of the heartbeat [des battements du cœur] was followed by three ordinary pulsations, then a small pulsation after which a normal beat [un battement normal] returned. A new suspension occurred, and so on indefinitely. These periodic irregularities often change several times in a day; one sometimes observe their appearance and disappearance at very short intervals. (Etienne-Jules Marey, Physiologie médicale..., p. 420, my trans.)

In the first chapter of his large essay The Pulse. Illustrated with 59 Sphygmographic Tracings (1882), Broadbent commented the conceptual change that had occurred from Antiquity to Modern Times. The list of pulse differentiae he attributed to Herophilus was not completely accurate—he swapped frequency with speed (see vol. 1, chap. 4)—but he was correct in stressing the fact that rhythm did not mean for Herophilus “the regularity or frequency of the beats” as it was now the case.

[Herophilus] described four qualities in the pulse, size, frequency, force, and rhythm, and gave special attention to the rhythm of the arterial pulsation, by which was meant the relative duration of the wave and the interval, not the regularity or frequency of the beats. (W. Broadbent, The Pulse, 1882, p. 4)

However, his own conception of rhythm was not as advanced as that of the German or the French. In chapter 2, Broadbent described “The Action of the Heart” under three entries: “1. Frequency. […] 2. Rhythm. [...] 3. Force.” Rhythm was clearly assimilated to regularity but it was also strikingly differentiated from frequency.

2. Rhythm.—The rhythm, as well as the rate, of the pulse is determined by the heart, and the pulse, generally speaking, is regular or irregular according as the action of the heart is regular or irregular. The pulse, however, may be made irregular when the heart is acting regularly by beats failing to reach the wrist, and irregularity of the heart's action may be greatly exaggerated in the pulse. (W. Broadbent, The Pulse, 1882, p. 23)

These assimilation between rhythm and regularity and differenciation between rhythm and frequency were again presupposed a little further down.

A complete account of the pulse, then, should specify (1) the frequency: that is, the number of beats per minute, with a note of any irregularity or intermission or instability of the rhythm ; (2) the size of the vessel [...]. (W. Broadbent, The Pulse, 1882, p. 44-45)

However Broadbent was aware of the semantic shift of the term “rhythm” and thought necessary to make himself clear. In this particular instance, he referred to the “strict sense” as denoting a time-relation between the sound of beats, and “not the regularity of the succession of heart-beats.”

The term rhythm is here employed in its strict sense, as denoting the time-relations of the first and second sounds of individual beats, and not the regularity of the succession of heart-beats. (W. Broadbent, The Pulse, 1882, p. 63)

At the end of the 19^th century, William Ewart, an English physician with a French education (1848-1929), wrote an interesting book entitled The Pulse-Sensations: A Study in Tactile Sphygmology (1894), where he intended to overcome “the relative neglect of a valuable clinical method” which resulted from “the contrast between the mechanical accuracy and elaborate detail of the sphygmogram, and the vague and inconclusive character of the pulse impressions hitherto gained by palpation” (Preface – p. vii). Ewart, who was attached to the qualitative measure of the pulse, was well aware of the effect of the mechanization of the pulse measure and record on “our mental ideation.” He noticed that, in his time, pulse rhythm had become almost identical with pulse wave.

The sphygmogram is indeed the only graphic representation of the arterial-pulse in clinical use, and from it is at present evolved our visual, and in most cases probably also our mental ideation in connection with the pulse-wave. (W.M. Ewart, The Pulse Sensations: A Study in Tactile Sphygmology, 1894, p. 12)

To prove his case, Ewart provided a number of those sphygmograms, some of them taken in Kries' and Marey's books.

William Ewart, The Pulse Sensation..., 1894, fig. 153, p. 354.

Although it was not a direct shift and the semantic evolutions have been quite intricate, the medical concept of rhythm underwent between the 16^th and the 19^th centuries a spectacular transformation. Whereas it was first conceived as a succession of time-lengths organized according to rational proportions and related with the circuits of the heavenly bodies, it was finally defined as a succession of beats or pressure waves, characterized by its frequency and regularity. Medicine adapted the old Platonic-Aristotelian concept based on the Ancient poetic and musical metric to a more Modern metric model based on continuous repetitive variations devoid of metaphysical background.

This does not mean though that the old meanings were entirely replaced by newer ones. What happened was more like a multiplication and superposition of the different senses of the term rhythm. As the case of Broadbent showed us quite clearly, ancient ones were not forgotten and could at times re-emerge in particular occasions.

Next chapter

Du rythme dans le corps. Quelques notes sur l'interprétation du pouls par le médecin Hérophile

Jackie Pigeaud — 2017-11-10T08:00:00Z

J.-M. Pigeaud, « Du rythme dans le corps. Quelques notes sur l'interprétation du pouls par le médecin Hérophile. » In : Bulletin del'Association Guillaume Budé, n° 3, octobre 1978, pp. 258-267.

La littérature sur le pouls a été très abondante ; elle est maintenant réservée à l'archéologie de la médecine ; les philologues et les historiens de la philosophie auraient intérêt à la consulter. Nous voudrions réfléchir quelque peu à la définition du pouls par Hérophile. Ce médecin fut sans doute le premier à mesurer le pouls, sinon à prendre conscience de son importance. La collection hippocratique semble en effet indifférente à ce sujet. Hérophile, ce véritable inventeur de l'anatomie, à qui nous devons encore de nombreux noms des parties du corps, fut aussi le vrai découvreur du pouls. Dans l'admirable notice de son Rufus d' Éphèse, Daremberg cite deux textes contradictoires de Galien sur l'origine hippocratique du pouls ; l'un où il dit : « Hippocrate a le premier introduit la coutume qui prévalut après lui, d'appeler sphugmos tout mouvement des artères quel qu'il fût », l'autre où il écrit que bien qu' « Hippocrate n'ignorât pas l'art de l'interroger, il ne donna pas ce nom (de pouls) à tous les mouvements des artères ».

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Pulsations du corps en médecine. Sentir et mesurer par la musique

Concetta Pennuto — 2017-11-10T08:00:00Z

Concetta Pennuto, « Pulsations du corps en médecine », Histoire, médecine et santé, 11, été 2017, p. 55-76.

Cet article propose une illustration de la manière dont la musique a fourni, par le biais de ses harmonies et son langage, un outil aux médecins pour comprendre et maîtriser les pulsations du coeur. Après une courte exploration de l'acte de prendre le pouls dans l'Antiquité et au Moyen Âge, l'étude présente des exemples de médecins modernes qui utilisent non seulement les moyens de l'harmonie musicale (comme on le faisait dans la médecine antique), mais également la notation pour marquer, transmettre et communiquer la perception du pouls. Les médecins du xviiie et du xixe siècle créent des partitions de la pulsation cardiaque. La sensation individuelle de la pulsation est alors objectivée et mesurée dans la transcription en musique.

Mots-clés : pouls, musique, corps

This article introduces a panorama of the manner in which physicians made use of musical harmonies and language in order to understand and grasp the beatings of the heart. After a brief exploration of the way ancient and medieval physicians took the pulse, this study is concerned with some examples of modern physicians, which used not only musical harmonies (as did the ancients), but also music notes to write, pass down and communicate their perception of the beating. In the 18th and the 19th Centuries, physicians were able to create music score of the cardiac pulse. Thus the individual perception of it could be objectivised and measured by the notes.

Keywords : pulse, music, body

De pulsibus ad tirones. Galien et les médecins débutants : le pouls comme moyen de diagnostic et de pronostic

Dina Bacalexi — 2017-11-09T07:30:00Z

Dina Bacalexi, « De pulsibus ad tirones. Galien et les médecins débutants : le pouls comme moyen de diagnostic et de pronostic ». In : Bulletin de l'Association Guillaume Budé, n° 2, juin 2001, pp. 131-152.

Le traité de Galien Sur le pouls à l'usage des débutants (De pulsibus ad tirones) a été composé lors du premier séjour du médecin à Rome (162-166 après J.-C.) et retravaillé, comme d'autres traités, lors du second séjour, vers la fin du siècle. Notre objectif, dans cette présentation, sera d'analyser un traité clairement destiné à faire apprendre la médecine aux débutants (qui ne sont, cependant, pas des profanes), à savoir de comprendre la démarche de Galien qui, sans être clairement définie comme une démarche éducative, n'en est pas moins didactique, compte tenu des références fréquentes aux oeuvres plus détaillées, destinées, en toute évidence, à des médecins plus chevronnés. Nous allons donc étudier le système d'analyse du pouls, ce qui permet de comprendre pourquoi cet élément est capital pour tout médecin galénique ; nous nous efforcerons également de nous mettre à la place tour à tour du « maître » et des « élèves », qui vivent la même époque et sont confrontés au mode de vie de leurs patients, un mode de vie qu'il faut prendre en compte comme s'il s'agissait d'une donnée clinique de plus.

[....]

Rhuthmos

The Introduction of Rhythm in Life Science and Medicine (4th – 3rd century BC) – Part 1

Respiration and Pulse without Rhythm – Hippocratic School (5th cent. – 4th cent. BC)

Respiration and Pulse without Rhythm – Plato, Aristotle (4th cent. BC)

Respiration with Rhythm – Peripatetic School's Problems (3rd c. BC)

Pulse with Rhythm – Peripatetic Anonymus' On Breath (first half or mid-3rd cent. BC)

The Introduction of Rhythm in Life Science and Medicine (4th – 3rd century BC) — Part 2

Rhythm as Characteristic of Artery Pulse – Herophilus (ca. 325-255 BC)

Rhythm as Characteristic of Life Stages – Herophilus

Rhythm as Theoretical Stake

The Spread of Rhythm in Life Science and Medicine (1st – 2nd century AD) – part 1

Contestation vs Refinement of the Herophilean Pulse Rhythm Theory – The Pneumatic School (1st cent. AD)

The Spread of Rhythm in Life Science and Medicine (1st – 2nd century AD) – part 2

Refinement and Canonization of the Herophilean Pulse Rhythm Theory – Galen (129-ca. 200/216 AD)

The Spread of Rhythm in Life Science and Medicine (1st – 2nd century AD) – part 3

Pulse Rhythm as Part of a Mind-Body Identity Theory? – Galen

The Growing Naturalization of Pulse Rhythm from the 3rd cent. AD

Rhythm from Ratio to Beat – Modern Medicine (1540-1628)

Matching Pulse and Cosmic Cycles – Rhythm as Ratio (6th cent. – early 17th cent.)

Noting the Pulse – Rhythm as Ratio (Struthius and Mercado – 1540-1584)

Mechanizing the Pulse – Rhythm as Ratio (Harvey – 1610-1628)

Counting the Pulse – Towards Rhythm as Beat (Santorio and Galileo – 1602-1625)

Rhythm from Beat to Wave – Modern Medicine (1707-1894)

Rating the Pulse – Rhythm as Beat (from Floyer to Stokes – 1707-1878)

Timing the Pulse – Rhythm as Beat (Marquet – 1747)

Feeling and Hearing the Pulse – Rhythm as Sign (from Solano to Laennec– 1731-1819)

Tracing the pulse – Rhythm as Wave (from Hales to Ewart – 1733-1894)

Du rythme dans le corps. Quelques notes sur l'interprétation du pouls par le médecin Hérophile

Pulsations du corps en médecine. Sentir et mesurer par la musique

De pulsibus ad tirones. Galien et les médecins débutants : le pouls comme moyen de diagnostic et de pronostic

Respiration and Pulse without Rhythm – Hippocratic School (5^th cent. – 4^th cent. BC)

Respiration and Pulse without Rhythm – Plato, Aristotle (4^th cent. BC)

Respiration with Rhythm – Peripatetic School's Problems (3^rd c. BC)

Pulse with Rhythm – Peripatetic Anonymus' On Breath (first half or mid-3^rd cent. BC)

Contestation vs Refinement of the Herophilean Pulse Rhythm Theory – The Pneumatic School (1^st cent. AD)

The Growing Naturalization of Pulse Rhythm from the 3^rd cent. AD

Matching Pulse and Cosmic Cycles – Rhythm as Ratio (6^th cent. – early 17^th cent.)