In 1684, Georg Ernst Stahl distinguished in his doctoral thesis De Intestinis, eorumque morbis ac symptomatis, cognoscendis & curandis between the form of order of organic bodies that have a regulating soul, the dirigens microcosmicum, and aggregates of a more or less confused order. He called the form of order of organic bodies “organism” (organismus).Footnote 1 Only organic bodies live, and they live because their order corresponds to an “organism.” However, not many scholars adopted Stahl's theory of a categorical distinction between living and dead bodies.Footnote 2 In the first half of the eighteenth century, Wolffian and Boerhaavian professors dominated the teaching at German universities. The author of the entry “Organismus” in the twenty-fifth volume of Zedler's dictionary (1740), whose main editor, Carl Günter Ludovici, supported the Wolffian school,Footnote 3 only referred to the mechanical order of the “Organismus” as an “Organicum Mechanismum” (Zedler Reference Zedler1732–1754, vol. 10, c. 1866).
This article focuses on Stahl's concept of organism and its transformations in the writings of Théophile Bordeu and Paul-Joseph Barthez.Footnote 4 I will not highlight differences between Stahl's animism and Bordeu's and Barthez's vitalism, but investigate basic discursive constellations that contribute to a general framework of the concept of organism from 1700 to 1800.Footnote 5 I will also not retrace the detailed historical context of the transformation. Rather, I am interested in some aspects of its differentiation, especially with regard to discussions about multiple agents, the relation between irritability and sensibility, and adequate explanations of observed phenomena.
My main thesis is that the concept of “organism” in Stahl, Bordeu, and Barthez is based on a combination of three explanatory tools, and that the reconstruction of its problematic framework is important for an understanding of the development of the life sciences and their overall influence on other discourses around 1800 (cf. Cheung Reference Cheung2007a). The tools refer to (1) regulating agents, (2) functional interactions, and (3) stimulus-reactions-schemes within individual organic systems of forces. Three other themes that are widely discussed throughout the eighteenth century are closely related to these explanatory tools: energy, sympathy, and sensibility. The stimulus-reaction-scheme explains how an organic part interacts as a (sensitive) agent with its environment, functional interactions relate local agents (for example, organs) or forces to each other through exchange and transformation processes, and the regulating properties of the agent integrate all actions into a common network that maintains a balance of forces in a closed energetic system. Around 1800, the combination of these tools formed a major problem in various research fields, such as physiology, embryology, comparative anatomy, anthropology, and philosophy.
After Stahl established his concept of organism in Halle, Boissier de Sauvages referred to Stahl's writings in his lectures in Montpellier.Footnote 6 Bordeu and Barthez were his students. They also had close relations to Diderot and the French encyclopedists.Footnote 7 Like Stahl, Bordeu and Barthez refer to a regulating principle of energetic dispositions and to the systemic interaction of organic parts in order to adequately explain the phenomena of organic bodies. They call this form of order of organic bodies an “organism” (organisme).Footnote 8 Bordeu analyzes the agency of glands that possess a proper sensitivity. Stimulus-reaction-schemes of these organ-specific sensitivities determine the activity of local agents and contribute to the systemic interaction of organic parts within the whole body. After Bordeu, Barthez discusses the problem of the central regulation of the systemic interaction of local sensitive agents.
The first section of the essay refers to Stahl's concept of organism around 1700 and its transition into the French context of the so-called Montpellier vitalism. The second section examines Bordeu's theory of local sensitive agents. The third section focuses on Barthez's vital principle. The fourth and last section resumes basic aspects of Stahl's, Bordeu's, and Barthez's concepts of organism and discusses their impact on various discourses at the end of the eighteenth and in the first half of the nineteenth centuries.
Stahl's Concept of “Organism”
In 1693, Friedrich Hoffmann becomes professor of medicine at the University of Halle. Like Hermann Boerhaave, Hoffmann defines “living bodies” as “hydraulic machines, in which fluids are moved through impulse and pressure in tubes of solid parts” (Hoffmann [Reference Hoffmann1718] 1728, 105).Footnote 9 One year after Hoffmann, Stahl becomes the second professor of medicine.Footnote 10 Stahl calls the order of individual organic beings an “organism.” He categorically distinguishes it from the “mechanism” of hydraulic machines.
Stahl did not accept Malpighi's theory of blood circulation through capillaries. For Stahl, normal blood circulation, which is powered by the heart and indicated by the pulse, depends on “pores” in parallel or crossing vessels that transport liquids. If the tension is high, pores close, and if the tension is low, they open. The movements of “contraction” and “relaxation” are “tonic movements.” They depend on the tonicity of tissues. The influx and the draining away of blood thus results from the contraction and relaxation of vessels.Footnote 11
In De Motu Tonico Vitali (1692),Footnote 12 Stahl focuses on the occurrence of irregular blood movements during certain “diseases,” such as “nosebleed,” “monthly cleanings” of women, the “shaking” and “shuddering” during “fever,” and the interruption of the blood-flow in a part of the body (Stahl 1735, 554–576). The capacity of an organic body to change these movements and to heal itself in redirecting them, leads Stahl to the assumption that such bodies can regulate the “physiology” of fluids and the “interaction of vital acts” (concursus actuum vitalium). This self-regulation requires an autonomous agent that operates as a Hippocratic vis mediatrix “without the intervention or cooperation of any other moving principle” (Stahl Reference Stahl1831–1833, vol. 1, 234). Stahl calls this agent a “soul”: “The Causa Efficiens or the being that regulates the Motum Tonicum is the soul, as far as it produces and sustains life” (Stahl [Reference Stahl1724] 1735, 609). The “soul” regulates the tonic movement of tissues and thus changes the direction, the exchange, and the quantity of fluids in and between vessels and organs. However, these changes are often initiated through a “mechanical irritation” of organs (cf. Stahl [Reference Stahl1684] 1704, 21). The irritation of organs results from a simple stimulus-reaction-scheme between material parts. It affects the energy regime of an organic part, and this change is mediated to the regulating agent. The regulating central agent acts itself according to the general fixed energy plan of the entire organic body. It maintains the distribution and usage of local energetic regimes or “forces.” The “logic” (ratio) of this plan represents the general form of a processual order that coordinates the flux of liquids, their secretion or excretion, their transformation into tissues, and the organization of solid parts.
Inner organs show numerous small “nerves” although they do not possess the same “sensitivity” as the outer parts of the body. They are also not moved from one place to another. Stahl concludes that these small nerve nets are used by the central agent (cf. Stahl [Reference Stahl1724] 1735, 647). The “soul” regulates the tonicity of tissues and the activity of organs through these nerve nets. It is not divided or multiplied into various vegetative, animal and human souls, or “spirits” and “archei.”Footnote 13 Rather, it is the only cause of the “vital, contracting and relaxing movement of the soft solid parts” (motus partium solidarum molliorum densatorius & relaxatorius vitalis) (Stahl Reference Stahl1692, d3v).Footnote 14 This movement constitutes the life of organic beings. Living bodies die when their vessels lose their tonicity and become flabby. However, the loss of tonicity only depends on the weakening of the regulating activity of the soul-agent.
In his dissertation of 1684, Stahl already called the “soul” of organic bodies a “moving principle” (principium movens) and the “microcosmic director” (τò Dirigens Microcosmicum) of their development and existence.Footnote 15 The source of the force of this “active being” (ens activum) is an “organic, or rather organizing energy” (energia organica seu potius organizans) that expresses itself through an organized body. The organized body thus serves as an “instrument” for a “system of operations” of the soul.Footnote 16 A “mechanic energy” (energia mechanica) that sustains the dynamic order of organic bodies as a pure source of action “without any purpose or goal” (sine ullo fine aut scopo) could not have the same effect as an “organizing energy.”Footnote 17 The organizing energy forms the organic body according to a “plan,” and it maintains a certain “natural tonus” (tonus naturalis) in all organs in “regulating” the exchange of liquids between the vessels.Footnote 18
Human faculties of memory and thinking are just extensions of faculties of the central agent. It is the same “soul” that regulates the tonic movement and that thinks (cf. Stahl Reference Stahl1695; and Reference Stahl1701a, 5–6). However, different properties and types of souls belong to different, preformed types of living beings. The human soul is capable of organic ratio and of reflexive ratiocinatio. Stahl discusses the difference between organic and reflexive thinking in the essay Propempticon inaugurale de differentia rationis et ratiocinatis et actionum (1701a).Footnote 19 In the essay, he refers to explanatory schemes of pre-formed, organizing instincts, which emerge in the second third of the seventeenth century in France and England. As instincts regulate organic inside-outside-relations through a pre-formed plan of functionally interconnected operations, the inborn ratio of an “organism” represents for Stahl the capacity of a soul to regulate the whole system of inner organic movements without any conscious acts. On the basis of the organismic differentiation of sensory data and irritations, the “concluding thinking” (ratiocinatio) can perform its reflexive acts.
The organic ratio is not the ratio of man-made machines. Unlike the parts of a watch, the parts of an organic body systematically constitute and sustain the order of all the other parts. Through this functional interaction of “organs,” an organic body “develops, feeds, propagates, and sustains itself” (Stahl Reference Stahl1720, 47).Footnote 20 The “formation” of organic bodies first results from the accumulation of “small particles” (minima corpuscula) that are “apt” (apta) for an organic organization. These particles are “point for point” (de puncto in puncto) arranged and distributed.Footnote 21 The regulating agent thus constitutes the “life of the body” (vita corporis).Footnote 22 The “main field” (locus praecipuus) of its operations affects the “functions” that determine the “circulation,” “secretion,” and “excretion” of liquids (cf. ibid., 24 and 44–46). However, the “formal organism” (organismus formalis) depends for its “maintaining action” (Actus conservatorius) on the “material organism” (organismus materialis) or the physical organization of an “organic system” (cf. Stahl [Reference Stahl1684] 1704, 37 and 40). The agent of the formal organism acts as “a single soul, that can systematically move the whole system and each of its parts if it is combined with such an entire [organic] system” (una Anima, toti tali Systemati addita, illud in toto, & qualibet parte, systematice movere possit) (Stahl Reference Stahl1720, 35). The formal and material organism represent together the “vital organism” (organismus vitalis).Footnote 23 In this “vital organism,” the “mechanism” of parts is an “instrument” for the regulating soul. The organs of the senses are “made for” (destinata) feelings and perceptions, the muscles for movements, and the tongue for “the articulation of words” (ibid., 16 and 21).
The central agent of the vital organism is a “non-corporeal substance” (res incorporea) (ibid., 16). Its immaterial movements are transmitted to the physical organic body. This is for Stahl a fact of experience in human bodies. He mentions passions and anxieties that correspond to certain corporeal “symptoms.” How such an influence could possibly be explained, seems an “insoluble question” (quaestio insolubilis) (Stahl Reference Stahl1831–1833, vol. 1, 420). The only adequate interpretation seems to be a model in which the organizing energy of a regulating soul expresses itself in “corporeal things.” As an “energetic being” (Ens Energeticon), the soul has to act in and through an organic body, and the body's “disposition” (dispositio) is “apt” for the soul's actions: “the souls possess energy to act in, in relation to, and through bodies; further on, to form and construct themselves these bodies with such a mechanico-organic ratio and proportion, that the bodies can carry out the grade [of intensity] and the goal of their actions” (Stahl Reference Stahl1720, 104). Within a Hippocratic medical tradition, Stahl thus transforms various agent and system theories of organic order of the seventeenth century – theories of archei, plastic natures, instincts, and preformed germs – into a new concept of “organism” that is based on regulating agents, functional interactions, and stimulus-reaction-schemes within a system of forces and organized organic structures.Footnote 24
Like Stahl, Ralph Cudworth, who was one of the leading figures of the Cambridge Platonists,Footnote 25 criticized the dualistic ontology of the Cartesians. His notion of “plastic nature” in The True Intellectual System of the Universe (first published in 1678) directly preceded Stahl's concept of organism.Footnote 26 For Cudworth, not only the thinking activity of humans, but also the “self-activity” of organic bodies cannot be explained through the parts of an “extended bulk” of matter that differ only in “magnitude, figure, site, motion, and rest.”Footnote 27 The development, nutrition, and generation of plants, animals, and humans, as well as their “instincts” point for Cudworth with evidence to an organizing “energy” or “plastic nature”: “For the several parts of matter distant from one another, acting alone by themselves, without any common directrix, being not able to confer together, nor communicate with each other, could never possibly conspire to make upon one such uniform and orderly system or compages, as the body of every animal is” (Cudworth Reference Cudworth1995, vol. 1, 252–253). The plastic nature represents “one and the self-same thing that directs the whole” (ibid., 252). There is only one plastic nature in each living being: “the same thing, which delineates the veins, must also form the arteries; and that which fabricates the nerves, must also project the muscles and joints; it must be the same thing that designs and organizes the heart and the brain, with such communications betwixt them” (ibid.).
Some years before Stahl, Cudworth thus developed a theory of organic order in which a single energetic agent uses mechanical organizations for the expression of its self-activity that is categorically different from thinking. Jean Leclerc's French translation of parts of Cudworth's The True Intellectual System in the Bibliothèque choisie (1703–1706) and his debate with Pierre Bayle transferred the English context of vital and energetic organic agents to the Continent.Footnote 28 It is not clear if Stahl had read Cudworth's The True Intellectual System, but Bordeu and Barthez certainly knew of Leclerc's translation and Bayle's critique. However, like Jan Baptist van Helmont's theory of archei, Cudworth's theory of organic order was embedded in a metaphysical and cosmological framework that was difficult to combine with the scientific standards of an experience-based objectivity that prevailed at Montpellier. Barthez explicitly refers to Cudworth and criticizes his notion of plastic natures as “occult forces.”Footnote 29
In 1751, Boissier de Sauvages became the director of the medical faculty of Montpellier. In his Nosologia methodica, first published in Latin in 1759,Footnote 30 Sauvages refers to an “internal sensitive and moving principle” (principe interne sentant et mouvant) that constitutes “life” in the organic bodies of animals and humans. While physical and chemical “forces” (such as “gravity,” “attraction,” and “elasticity”) explain as “causes” certain sets of movements of “inanimated bodies,” “vital forces” (forces vitales) represent the “sufficient reason” for specific phenomena of “living bodies.” Sauvages classifies these phenomena as regulated operations.Footnote 31 He explains them through a central “moving force”: a “soul” that has a direct influence on the organic “machine.”Footnote 32 The “soul” is the “principle of life” (principce de la vie) (cf. ibid., 70). It regulates the movements of the heart, of “respiration,” and of the limbs (cf. ibid., 70 and 80). However, in the organic machine, the vegetative “faculties” and “functions” of “nutrition,” “secretion,” “digestion,” and “generation” are operated through “inanimated forces.”Footnote 33 Sauvages highlights that the systemic effect of inanimated and animated forces on the whole organic body, through which the actions of different organs are correlated, and the regeneration of these forces after an illness cannot be explained by the sum of small forces of a “hydraulic machine.”Footnote 34 Rather, both processes depend on an energy regime.
The “soul” expresses its regulating activity through a certain quantity of “moving power” (puissance motrice) that is distributed as an energetic “reservoir” to local agents within individual living bodies. In these local agents, the “power” acts through specific vital forces. Vital forces transform into “actual forces” (forces actuelles) that are used up through action and “potential forces” (forces potentielles) that regenerate the energetic balance:
The moving power, that is a kind of reservoir of all forces, is distributed to the different parts of the body, as the heart, the chest, and the limbs. However, it always remains more or less the same at a certain hour of the day or during a certain number of years. It follows that every day the regeneration of forces is equal to their consumption. (Sauvages Reference Sauvages1770–1771, vol. 1, 96)Footnote 35
Besides perceptive and cognitive faculties that differ in animals and humansFootnote 36 and the continuous regulation of certain “functions,” the “soul” is also capable of emotions as “desire,” “anger,” and “anxiety.” These emotions have a strong influence on the performance of the organic machine, especially on the “tension” of vessels and the circulation of blood.Footnote 37 Sauvages thus works with a concept of “organism” similar to Stahl's, and he categorically distinguishes between living and dead bodies. But Sauvages focuses in a more detailed way on the common order of humans and animals and its relation to the structure of “inanimated” bodies of plants.Footnote 38 He also emphasizes the autonomy of local organic agents.
Sauvages’ students Bordeu and Barthez also adopt Stahl's distinction between two forms of order – the “organism” and the “mechanism” –, but they are mainly interested in the energetic regime of organic agents with two basic properties: self-activity and sensibility or sensitivity. Through both properties, organic agents (such as fibers, tissues, organs, or systems of organs) execute sequences of actions according to stimulus-reaction-schemes. Stimulus-reaction-schemes of local organic agents within individual living bodies are characteristic for Francis Glisson's fiber model. Besides the models of organic order of the Cambridge Platonists and of Stahl, Glisson's fiber model thus represents a third important explanatory scheme that influenced Bordeu and Barthez.
In De Natura substantiae energetica (1677), Glisson focused on the autonomy of suborganic units that possess a specific energetic disposition and a faculty of “natural perceptions” (perceptiones naturales) through which they turn stimuli into actions. While Glisson still explained the secretion processes of the gall bladder in Anatomia hepatis (1654) through nervous stimuli, he outlined in 1677 the metaphysics of a principle of individuation that relied on a self-organizing substance and its non-conscious perceptive or “irritable” properties in organically organized matter.Footnote 39 Through “natural perceptions” of organic parts, organic bodies “live” as individuated organized composites of matter. Perceptions receive, transform, and react to stimuli in a way that is specific for the energetic disposition of local agents. Bordeu and Barthez transform Glisson's concept of irritable “fibers” and “natural perceptions” into models of the self-activity of local agents that sense the stimulus without having nerves. As perceptive agents, sensitive agents receive, assimilate, and react to stimuli in a way that is specific for their energetic disposition.
Bordeu and Barthez are certainly influenced by the new sensationism that emerges on the Continent in the first half of the eighteenth century. However, as Baasner notes, the English and French sensationism of Locke and Condillac explains the relation between perceptions and sensations, but not the physiology of sensibility as an inherent property of organic bodies (Baasner Reference Baasner1988, 240).Footnote 40 Bordeu often emphasizes that the sensibility of glands “should not be confused with the usual sense of sensibility (sentiment proprement dit)” (Bordeu Reference Bordeu and Richerand1818, vol. 1, 166).Footnote 41 For Bordeu and Barthez, sensitive stimulus-reaction-schemes are basic operative modi of the functional interaction of organs. They thus argue against the Hallerian dualism of nervous sensibility and muscular irritability.
Bordeu and the Local Sensibility of Organs
In 1739, Bordeu began his studies at the medical faculty in Montpellier, attending Sauvages’ lectures (cf. Larre Reference Larre2001; and Williams Reference Williams, Elizabeth1994, 28–29). In his first doctoral thesis Dissertatio physiologica de sensu generice considerato (1742), Bordeu distinguishes the sensibility of self-moving organs from muscular irritability.Footnote 42 In his second doctoral thesis Chylificationis historia (1743), he analyzes the functional interaction between different organic processes during digestion. Stimulus-reaction-schemes and the functional interaction of digestive glands with other organs finally becomes the central theme of his main work, the Recherches anatomiques sur la position des glandes, et sur leur action (1752).
Bordeu often discusses the influence of Stahl's medical theory on the research and teaching in Montpellier.Footnote 43 He emphasizes that, through a combination of “chemical” experiments and medical experience, Stahl could establish a sound critique of mechanical theories of the order of organic beings. However, Bordeu does not accept Stahl's model of a single regulating soul. For him, an adequate interpretation of organic phenomena requires a network of regulating agents (cf. Bordeu Reference Bordeu and Richerand1818, vol. 1, 204–205; and Lavabre-Bertrand Reference Lavabre-Bertrand1992, 11–13).
In Recherches anatomiques, Bordeu investigates the activities of glands that are “destined for separating some specific humor and for discharging it afterwards.” He distinguishes the separating action as “secretion” (secrétion) from the discharging action as “active” or “passive excretion” (excrétion active ou passive) (Bordeu Reference Bordeu and Richerand1818, vol. 1, 50). The active excretion results from the “proper force” (propre force) of glands, the passive excretion from the “compressions” (compressions) of neighboring organs. However, in “active glands,” it is often not possible to distinguish between different phases of secretion and excretion because the “humor” (as the saliva in salivary glands) issues from the excretory vessels in the same proportion as the secretory vessels separate it. Only “passive glands” possess a “reservoir” (cf. Bordeu Reference Bordeu and Richerand1818, vol. 1, 176–178).
For Bordeu, Boerhaave ignored the self-activity of the salivary gland because he only referred to the contraction of “neighboring parts” (the sternomastoid muscle) to explain excretion. Bordeu, however, comes to the conclusion that the contraction of the sternomastoid muscle during the chewing process prevents the excretion of saliva (Bordeu Reference Bordeu and Richerand1818, vol. 1, 58–63). He thus has to develop a new model of the activity of the gland. This model is based on the distinction between the “excitation” (excitation or irritation) of a gland through “nets of nerves” and its “sensibility or sensation” (sensibilité or sensation).
Nerves, Bordeu argues, induce a specific “tonicity” (tonicité) in the tissues of glands. This tonicity corresponds to a “general sensation” (sensation générale) or “attention” (attention) of the gland to react to the changes of the blood current that flows around it (Bordeu Reference Bordeu and Richerand1818, vol. 1, 163–164). Changes of the blood current depend on the activity of nerves that are attached to arteries. If the nerves are active, the arteries “drive” more blood to the bladders. However, the change that affects the general sensation of the salivary gland is only an indicator for it to initiate the secretion process according to its energetic disposition and specific sensibility. Bordeu also calls the specific sensibility of a gland its “taste” (goût) (Bordeu Reference Bordeu and Richerand1818, vol. 1, 162). During the secretion process, the blood passes through various “orifices” of the secretory vessels of the gland. The size of these orifices depends on the activity of sphincters and their “nervous fibers” that are themselves “irritated” by various types of particles of the incoming blood.
For Bordeu, irritation, general sensibility, and specific sensibility are not only characteristic of the “self-activity” and the “life” of certain glands, but also, in general, of organs. The life of organs is not directly correlated with the general blood circulation and the heart rate. Within organic bodies, each organ exists as a “proper body” (un corps à part) and “a kind of a separated machine” (une espèce de machine à part) that is made out of fibers (cf. Bordeu Reference Bordeu and Richerand1818, vol. 1, 187, and vol. 2, 802 and 942; Duchesneau Reference Duchesneau1982, 383; and Boury Reference Boury2004, 99).Footnote 44 Through their actions and energetic dispositions, these “machines” establish a certain “regime” or “domain” within which they influence or interact with other organs. Each regime can be characterized through three aspects: First of all, it is functionally determined through the repetition of certain successions of movements. Further on, it depends on the distribution of a certain “humor” that organs produce according to their innate “temperament” (tempérament) and on the net of vessels and tissues in which this humor circulates (cf. Bordeu Reference Bordeu and Richerand1818, vol. 2, 752 and 948).
In the first and second parts of Recherches sur les maladies chroniques (1775), Bordeu often refers to the “regularity and the order of functions” (régularité et ordre des fonctions) in individual organic bodies (Bordeu Reference Bordeu and Richerand1818, vol. 2, 802). This order results from the mutual “limitation” of the “forces” of sensitive organs. He calls this order of functions a “harmony” or an “equilibrium” of actions. Within the harmony of actions, “functions” characterize certain types of regular successions of movements that are caused by specific forces. Each function depends at the same time on the performance of all the other functions and “regimes”: “each of these mutually enchained and linked functions requires for its natural operation the support (concours) of all the others” (Bordeu Reference Bordeu and Richerand1818, vol. 2, 805–806).Footnote 45
Within the “harmony of organs” (harmonie des organes) and their functional interaction, Bordeu differentiates three “main centers” (principaux centres) that have a stronger regulating influence than others: the “stomach,” the “heart,” and the “brain.”Footnote 46 They represent the “triumvirate” or the “tripartite support of life” (trépied de la vie). Their systemic interaction represents the minimal condition for the “life of each part and of each function.” The regime of the stomach first assimilates incorporated particles into a pulp and then transforms parts of this pulp into the “blood.” The “blood” becomes part of the regime of the heart that, combined with respiratory processes, supports the general circulation of liquids for the growth, differentiation, and regeneration of tissues. Finally, the brain regulates through a network of nerves, which spreads like a “polyp” into the smallest units of the body, the general tonicity in the whole organic system. Three “general functions” (fonctions générales ou communes) correspond to the actions of the three main centers of the animal economy: (1) the nervous, (2) the respiratory and circulatory, and (3) the digestive function. Various “particular functions” (fonctions particuliéres) are “subordinated” to the general functions, for example secretion and excretion, muscular movements, and the “usage” of the senses. The interaction of organs that regulate different local regimes manifests itself physically in the “oscillations” (oscillations) of tissues and in a perpetual “trembling” (tremblement, secousse) of the whole body. Through these oscillations, organs communicate their different energetic states and “excitements” (cf. Bordeu Reference Bordeu and Richerand1818, vol. 2, 802 and 830–831).
The “general life” of individual organic bodies results from the interaction of the different energetic dispositions and regimes of organic parts: “The general life (vie générale), that is the sum of all the particular lives (vies particulières), consists in a flux of a controlled and well-measured movement that successively occurs in each part. It determines the execution (exercice) of its functions, and forms the entire framework (trame) of our life” (Bordeu Reference Bordeu and Richerand1818, vol. 2, 829–830). Regulating agents, functional interactions, and stimulus-reaction-schemes of sensitive organic parts thus form a new conceptual platform of organic order. Bordeu replaced the regulating activity of Stahl's soul-agent through a multiplicity of local regulating centers. However, he is also aware of the problem that the correlation of the activity of all local agents requires a single “maintaining force” (force conservatrice) that is not controlled by another agent (cf. Bordeu Reference Bordeu and Richerand1818, vol. 1, 163; Duchesneau Reference Duchesneau1982, 372–373; and Boury Reference Boury2004, 175). Barthez focuses exactly on this problem.
Barthez's Vital Principle
In 1750, eleven years after Bordeu, Barthez began his studies in Montpellier. In 1759, he became a professor and later, in 1785, chancellor of the university. While Stahl and Bordeu mainly explained the physiology of the human body, Barthez is more interested in a general theory of life that includes plants and animals.
For Barthez, the problem of a central regulating agent, which is different from the brain, is first of all a problem of a proper or adequate interpretation of organic phenomena. The problem of an adequate interpretation of organic phenomena is a major theme in the medical discourse that reaches from Sauvages’ Nosologia methodica to Johann Georg Zimmermann's Von der Erfahrung in der Arzneykunst (1763–1764) and Jean Senebier's L'Art d'observer (1775).Footnote 47 However, the problem had already been extensively discussed by Cartesian philosophers in the first half of the eighteenth century. I will briefly reconstruct the position of David-Renaud Boullier – one of the most influential figures in the debates about animal souls before 1750 (cf. Ehrard Reference Ehrard1963, vol. 2, 682) – to refer to this Cartesian context.Footnote 48
Boullier accepted the dualism of mind and body as an adequate interpretation of human existence, but he rejected the reduction of phenomena of organic bodies to “Cartesian automata” (Automates Cartésiens).Footnote 49 In the Essai philosophique sur l'âme des bêtes, first published in 1728,Footnote 50 Boullier introduced a “sensitive principle” (principe sensitif).Footnote 51 The principle acts as a cause in animal bodies according to “pleasant” and “unpleasant” or “painful perceptions” (perceptions affligeantes) (Boullier [Reference Boullier1728] 1985, 359). Through this stoic principle, animals are capable of self-activity and Leibnizian small, unconscious perceptions. Boullier justifies his hypothesis with the fact that animals strive for pleasant and avoid unpleasant perceptions or feelings. He calls this drive “desire” (désir). Situated in the brain, it regulates the body machine without reflexive properties (cf. Boullier 1985, 359–360).
Like Barthez later on, Boullier was not so much interested in the ontological status of agents – for example, their materiality or immateriality –, but in adequate explanations of organic phenomena.Footnote 52 In his Traité des vrais principes qui servent de fondement à la morale, an essay that precedes the Essai philosophique in the second edition of 1737, Boullier emphasized that an explanation of a “succession of phenomena” (suite des Phénomènes) must rely on a “fixed proportion” (proportion fixe) between the visible effects and their cause (Boullier 1985, 103). Such a “proportion” represents the “principle” or the “general law” of the succession. In order to show that organic phenomena represent “successions of phenomena” (suite des Phénomènes) that cannot be explained by physical and chemical laws of impulsion, attraction, and affinity, Boullier referred to concepts of animal instincts. From Seneca and Cicero to Shaftesbury and Bayle, he discussed the classical examples of instinct-actions – such as the nest-building of birds – and concluded that the only adequate principle to explain such a “tabulator of industrious movements” (tablature de mouvemens industrieux) is an inborn agent-like sensitive principle that unconsciously reacts to various outer conditions (cf. Boullier [Reference Boullier1728] 1985, 366).Footnote 53 In allusion to Descartes’ genius malignus, Boullier argued that a God who encourages humans to assume that there is a sensitive principle in organic bodies, although he is moving himself the mechanism of an automaton, would be like an artist, who aims at deceiving the observer of a statue that completely resembles a human being. God thus would be a deceiver if animals are just automata. Through this inversion of occasionalist positions, Boullier comes again to the conclusion that the “organized bodies” of animals must possess a regulating sensitive principle.
Like Boullier, but with explicit references to Hume and Newton,Footnote 54 Barthez focuses on the problem of adequate explanations of organic phenomena in the Discours préliminaire of the Nouveaux éléments de la science de l'homme, first published in 1778.Footnote 55 Barthez argues that all scientific explanations rely on causes, “but only insofar as the causes can be known through experiences” (mais seulement en tant qu'elles peuvent être connues d'après l'expérience) (Barthez 1806, vol. 1, 6). The ideal form of such a cause is a mathematical formula that explains the “law” of successions of phenomena. The only adequate explanation of various successions of organic phenomena is, for Barthez, a regulating cause that he calls “principle of life” (principe de la vie) or “vital principle” (principe vital). It represents the “experimental” or “general law” (loi expérimentale ou générale) of the order of individual organic bodies. The principle operates as a preexisting “inborn faculty” (faculté innée) that regulates the development, the physical “organization,” and the “drives” or “appetites” of plants, animals and humans:
While the organs only gradually perfect themselves and take form, the Principle of Life is, from the first moment of the formation of organs, perfect in the generative and vital functions that it executes. Upon the appearance of appetites, each animal is directed by its Principle of Life to search in a confused manner the objects of these appetites, and to search them when they manifest themselves. It is not probable that the blindness of these impulsions and the specificity of the choice are only the effects of a [physical] organization. (Barthez 1806, vol. 1, 104)
In this passage, Barthez combines his explanation of the operational mode of the vital principle with instinct and preformation debates. I will briefly refer to this connection. In Die vornehmsten Wahrheiten der natürlichen Religion (1754) and Allgemeine Betrachtungen über die Triebe der Thiere, hauptsächlich über ihre Kunsttriebe (1760), Hermann Samuel Reimarus investigated the correspondence between animal appetites and the faculty of an organic body to satisfy these appetites. Against Condillac, Reimarus argued for a general theory of a system of inborn drives that causes instinct-actions of animals and humans.Footnote 56 Besides Reimarus’ system of drives, theories of inborn patterns that regulate the development and functioning of individual organized bodies can be found in Charles Bonnet's preformation theory. In Contemplation de la nature (1764) – to which Barthez refers in the Nouveaux éléments (Barthez 1806, vol. 1, 56) –, Bonnet explained the development of systems of interacting organic parts in plants and animals through preformed germ-fiber-units with inborn regulating properties and a “vital force” (Puissance vitale).Footnote 57 The problem of inborn drives that regulate movements thus connects instinct and preformation debates with Barthez's concept of organism.
In the first edition of the Nouveaux éléments (1778), Barthez only briefly mentions the vital principle as a higher, coordinating principle of order besides chemical and physical laws (Barthez Reference Barthez1778, 5). However, in the second edition of 1806, Barthez discusses the vital principle in a much more detailed way.Footnote 58 It becomes, like Stahl's soul, the central regulating “cause” of concerted movements in organic bodies.Footnote 59 The regulating activity of the principle is present in all organic parts. It determines the general and specific sensibility of organs, the successions of visible “muscular movements,” the invisible “tonic movements” of smoother organic parts, and metabolic processes (cf. Barthez 1806, vol. 1, 20).
Within the system of organic interactions, Barthez distinguishes between “forces,” “functions,” and “mechanisms.” As for Stahl and Bordeu, also for Barthez, a function defines specific and typical successions of movements through which a force expresses its activity in a “mechanism.” The mechanism represents a physical disposition of parts. In their totality, the physical dispositions of parts form the “organization” of an organic body.
The “intimate correspondence” (correspondance intime) between local agents is not mediated through “oscillations,” “nerve fluids,” or “animal spirits” (cf. Barthez [Reference Barthez1778] 1806, Bd. 1, 109; and Barthez Reference Barthez1798, Discours préliminaire, iv). It also results not from the sum of the activities of organic parts. Rather, all organs “sympathize” through a “balance of energy” (stabilité d'énergie) that is maintained by the vital principle (cf. Barthez Reference Barthez1798, Discours préliminaire, iv; Barthez [Reference Barthez1778] 1806, Bd. 1, 109 and 222). Already in De principio vitali hominis (1773), Barthez mentioned a “stable energy” (energia stabilis) that expresses itself in a “constant” general sensibility and a certain basic tonicity or “middle-tone” of organs. Through this general sensibility and tonicity, all organs of a single organic being are in a similar “sympathetic state” (affectum sympathicum), although they are not executing similar “functions” (functiones) (Barthez Reference Barthez1773, 13 and 15).
The vital principle maintains and supports the interaction of forces and local agents through a distribution of energy within the whole body, and the energetic disposition of each organic part, which corresponds to its specific sensibility,Footnote 60 interacts with the dispositions of all the other parts. Barthez calls this a “sympathetic” distribution of energy. The vital principle is also a “principle of sympathy”:
The forces of the Vital Principle are inherent in each part of the body that it animates, and they execute movements that are proper to these parts. But in general, these movements cannot subsist for a longer period, if the forces of each organ . . . do not freely sympathize or communicate with the system to which this organ belongs in the living body. (Barthez Reference Barthez1798, Discours préliminaire, iv)Footnote 61
The vital principle thus regulates the “correspondence” of the activity of organic parts in plants, animals, and humans. However, Barthez refers only briefly to the regulation of functions (as generation, nutrition, the movement of saps, secretions) in the “economy” of plants (Barthez [Reference Barthez1778] 1806, vol. 1, 57). He is mainly interested in the role of the vital principle in the “economy” of animals and humans. Their economy is composed of “vegetative functions” and of “animal functions.” Animal functions coordinate the activities of sense organs and of organs of movement.Footnote 62 The “fermentation,” “transformation,” and “organization” of food in various organs, the movement of the heart and of the arteries, the “generating faculty” (faculté génératrice) of the semen, and the maintenance of a certain heat of the blood in warmer and colder environments (as well as the “general changes” that affect medicaments) are caused through the “immediate activity” (action immédiate) of the vital principle. The human soul can only influence some organic processes through its “will” and its “passions” (cf. Barthez Reference Barthez1773, 9–10; and [Reference Barthez1778] 1806, vol. 1, 232–234, 240, 256, and 283). Vital movements are “unconscious” and “involuntary” (Barthez [Reference Barthez1778] 1806, vol. 1, 87).
In all living bodies, the “self-activity” of organs is an expression of the “total energy” (énergie totale) of the vital principle (ibid., vol. 2, 237). This energy is specific for each species. It determines the system of forces that only varies through contingent conditions that occur during the development and existence of organic bodies. The total energy of an organic body also delimits its natural lifetime.Footnote 63 However, there is a “reciprocal action” between the “weakening” of the vital principle and the occurrence of illness or the “corruption” of tissues and organs. If tissues are “corrupted,” the vital principle cannot properly express its forces (cf. ibid., 305–306).Footnote 64
During the development of an organic body, its total energy transforms into “sensitive” and “moving forces” (forces sensitives et motrices).Footnote 65 Both forces autonomously express their specific functions as if they were two separate faculties of a soul. Only the vital principle coordinates the effects and the intensity of their activities (cf. ibid., vol. 1, 56–57, and 179).Footnote 66 Barthez distinguishes two kinds of moving forces – “muscular forces” (forces musculaires) of quick, visible movementsFootnote 67 and “tonic forces” (forces toniques) of slow, “non-measurable” movements in vascular or visceral tissues – and of sensitive forces (general and specific sensibility) (cf. Barthez Reference Barthez1773, 5–6; and [Reference Barthez1778] 1806, vol. 1, 112–114). Sensitive forces cannot move corporeal parts.Footnote 68 They only establish a kind of communication between local agents and the vital principle. This communication does not rely on mechanical irritations, although such irritations can initiate it (cf. Barthez [Reference Barthez1778] 1806, vol. 1, 57, 177, and 182). Like Bordeu, Barthez thus distinguishes between a nerve-dependent, mechanical “irritation” and the “spontaneous” movement of sensitive organic parts (cf. ibid., 180).Footnote 69 However, for Barthez, this spontaneous movement always depends on the regulating activity of the vital principle.
Conclusion
After Descartes’ dualism of mind and body, Stahl's concept of organism and its transformation in Bordeu's and Barthez's models of organic order establish a new dualism: that of living and dead bodies. This dualism depends on a deep, invisible order behind the phenomena. The archeology of this order is, as I have argued, much older than Michel Foucault suggested in Les mots et les choses (1966).
Around 1700, the main elements of Stahl's concept of organism are the notions of a regulating agent, of functional interactions, and of stimulus-reaction-schemes within a dynamic system of forces or energetic dispositions. For Stahl, the regulating agent is an immaterial “soul” that operates through the mechanism of organized organic parts. Its total energetic potential is a faculty to develop individual organic architectures and to regulate the flux and transformation of liquids within these corporeal spaces. The basic explanatory pattern of the faculty of regulation depends on a hierarchy of expressions between the central regulating agent and specific forces.Footnote 70 For Stahl, each entity of this hierarchy is able to transform an inborn potential order into an actual order: Through the differentiation of its inborn potential order into the “formal organism” of “forces,” the soul expresses itself within an organized body. Through their differentiation into “functions,” the interacting forces express themselves in the “mechanism” of organized parts. Not only do functions translate vital, life-constituting forces into mechanical movements; they also “inform” the regulating agent of living bodies about changes within the organized body and in its environment. However, it is always the “organism” that defines the system and the balance of energetic dispositions that the “mechanism” expresses. In the hierarchy of the expression of regulating entities, functions always precede structures.
Around 1800, Georges Cuvier adopts the logic of this hierarchy in his vital economies of organizational types, although he criticizes the usage of seemingly occult properties (such as sensibility) in the “Montpellier school.” For Cuvier, the economy of organizational types results from the expression of an organizing “plan.” This plan differentiates its organizing potential into various forces that constitute the order of living bodies. The forces act through the operations of “functions” within organized anatomical structures. However, besides the harmony between organizing forces and organized structures, living bodies depend on the harmony of functional interactions between their inside and their outside. This double harmony, to which Barthez explicitly refers, defines for Cuvier the specificity of the inner and outer conditions of “life” in individuated living bodies (cf. Cheung Reference Cheung2000 and Reference Cheung2006a).
Bordeu and Barthez accept Stahl's basic explanatory pattern of regulation as an expression of an energetic agent or principle, but they apply it in a different way to the phenomena of organic bodies. Like Glisson, Bordeu refers to experiments on the activity of glands to prove that some of them possess a nerve-independent active force that regulates secretion and excretion processes. This active force operates according to a second inborn faculty: the faculty of sensibility or sensitivity. Glands do not perceive, but sense stimuli. Besides the general and proper sensibility of a local agent, the expression of forces and the execution of functions relies on the tonicity of tissues (which is regulated through the brain and mediated through nerves) and on their physical organization. Like Xavier Bichat later on, Bordeu combines the function of an organ – that expresses an active force in the energetic system of an “organism” – with the textures and properties of a system of various interconnected tissues.
Bordeu's concept of organism is based on a multiplicity of local agents that act according to their inborn active forces and their sensibilities. However, he is also aware of the problem that it is necessary to assume a central regulating principle of all organic actions during the development and existence of living bodies. After Bordeu, Barthez focuses on such a principle. He distinguishes between the different regulating properties of a single and unique “vital principle” that an observer of the successions of phenomena of organic bodies has to suppose in order to explain them. Similarly to Kant in his Third Critique, Barthez refers to the “vital principle” as a heuristic tool that adequately explains a certain set of phenomena of bodies and of their movements. However, Barthez establishes the concept of organism not in analogy to human agency, but according to specific explanatory patterns that rely on a hierarchy of expressions of sensitive and energetic entities with inborn organizing potentials.
Bordeu and Barthez criticize Stahl's soul-body-dualism. Like Diderot, both refer to the possibility that the regulating properties of organic bodies are the effect of organized and organizing matter. However, their explanatory patterns are based on a dualism between the energetic form of a regulating agent or of an ensemble of local regulating agents and the (physical) organizational form of organic parts. The relation between the energetic and the organizational form of a living body depends on the expression and transformation of organizing energies in mechanical movements.
At the turn of the century, the concept of organism that I have discussed in this article is related to various research fields. The problem of a regulating natural agent evokes discussions about the relation between the faculties of humans and living bodies. German idealists confront the self-reflexive order of human identity with the self-activity of sensitive organic agents; Cabanis and Maine de Biran sketch a sensationalist anthropology; Naturphilosophen develop a new organismic cosmology; and naturalists like Blumenbach, who focus on the development of organic bodies, discuss the regulating and constructive role of vital forces in embryonic structures. The problem of functional interaction is closely related to these debates. However, together with the problem of the order of organic systems, it also motivates discussions about energetic dispositions and the balance of forces that will play a major role in Claude Bernard's physiology around 1850. The problem of stimulus-reaction-schemes that combine sensitive properties with moving forces finally connects Bordeu's and Barthez's concepts of organism with the debates on reflex action that reach from Johann August Unzer and Georg Prochaska, to Charles Bell, François Magendie, and Johannes Müller.
