Theories of Perception and the Physiology of Mind in the Late Eighteenth Century

The role I am attributing to the nervous system is consistent with recent interpretations of the general trend of eighteenth century natural philosophy towards a monistic view of nature. Monistic did not, however, necessarily imply mechanistic, spiritualistic, materialistic, etc. The Cartesian dualism, with its theological and philosophical division of body from mind, did remain, but to conceive of the problems within these strictures would lead to the confusing label of ‘materialistic vitalist’, or ‘vitalistic mechanist’ for a large number of eighteenth century writers. Matter and mechanism no longer meant the passive, inert extension it did for Descartes; nor did soul or spirit mean the rational soul. Active matter and causally enchained soul were within the domain of the monistically-inclined natural philosophy. Voltaire F.-M. , “Matière”, Dictionnaire philosophique (London and Geneva, 1769). There were several editions between 1764 and 1776, with 1769 being the final version. For a complete edition with an introduction and notes, see that of Benda J. Naves R. (Paris, 1961); Roger J. , Les sciences de la vie dans la pensée française du XVIIIe siècle (2nd ed., Paris, 1971), pt iii, ch. i, 458–526; Gusdorf G. , Dieu, la nature, l'homme au siècle des lumières (Paris, 1972), 299f., esp. 304–5; Canguilhem G. , La formation du concept de réflexe (Paris, 1955), ch. iv; Vartanian A. , “Trembley's polyp, La Mettrie, and eighteenth century French materialism”, Journal of the history of ideas, xi (1950), 259–86; idem, Diderot and Descartes, a study of scientific naturalism in the Enlightenment (Princeton, 1953); idem, La Mettrie's l'homme machine, a study in the origins of an idea (Princeton, 1960), chs iv, vi; Goodfield J. , “Some aspects of English physiology: 1780–1840”, Journal of the history of biology, ii (1969), 283–321. For a recent review of ideas and a mine of bibliographical information concerning activity in nature, with special reference to the use of psychological concepts in the fundamental categories of natural science (substance, matter, cause, force, etc.), see Smith R. , “The background of physiological psychology in natural philosophy”, History of science, xi (1973), 75–123, esp. 101–5.

“The precarious equilibrium achieved by the dualism of soul and body found itself ruptured in the eighteenth century, under the combined pressure of natural history and medicine …”. Gusdorf G. , op. cit. (ref. 1), 304.

Gay P. , The Enlightenment: An interpretation, ii, The science of freedom (London, 1970), 174–87.

French R. , Robert Whytt, the soul, and medicine (London, 1969), 161–8.

Bell Charles Sir , Idea of a new anatomy of the brain (privately printed, London, 1811; facsimile with bio-bibliographical introduction, London, 1966). An historiography of science which has stressed progressive innovation by men whose ideas approached ever nearer to our own, has made the priority dispute into a focus for historical investigation. The chequered career of Bell's Idea … is a vivid record of alternate bouts of praise and derision dedicated either to establishing or rejecting his claim to priority over the French physiologist, Magendie François Olmsted J. , François Magendie (New York, 1944), 93–123, reviews the literature immediately involved, including the articles of Bell, Shaw and Magendie, relating to their dispute. Gordon-Taylor G. Walls E. , Sir Charles Bell, his life and times (Edinburgh and London, 1958), 96–133: A sympathetic biography of Bell. The centrality of the Bell-Magendie dispute as an historiographical bias can be clearly seen in the tendency of Gordon-Taylor to structure the bulk of his treatment of Bell's neurological work around it. The dispute flared up again on the centenary of Bell's Idea. … See the several articles by Keith A. Guthrie L. Waller A. , The lancet, lxxxix (1911), and Waller A. in Science progress, vi (1911), 78–106; Bernard C. , Rapport sur les progrès et la marche de la physiologie générale (Paris, 1867), 9–15; 154–8; Carpenter W. , “Sir Charles Bell and physiological experimentation”, Popular science monthly, xxi (1882), 178–85; see also the recent book by Cranefield P. , The way in and the way out (New York, 1974); Bickel A. , “Eine historische Studie über die Entdeckung des Magendie-Bell ‘schen Lehrsatzes” (Bonn, 1901), repr. from Archiv für die gesammte Physiologie, Bd 84; Eckhard C. , “Geschichte der Leitungsverhältnisse in den Wurzeln der Rückenmarksnerven”, Beiträge zur Geschichte der Experimentalphysiologie des Nervensystems, x (Giessen, 1882), 133–69; Neuburger M. , Die historische Entwicklung der experimentellen Gehirn- und Rückenmar ksphysiologie vor Flourens (Stuttgart, 1897), 295–310. Bickel Eckhard Neuburger are far better on the neurological background to Bell's work. Even so, there is the tendency to build the arguments about neurology and Bell's interests around the steps towards the elucidation of the Bell-Magendie law. As an example of what Butterfield called “the Whig interpretation of history”, this concern for priority in the history of science has been especially destructive: Butterfield H. , The Whig interpretation of history (London, 1931; repr. London, 1973). The clear demonstration in 1821 by Magendie that the two spinal nerve roots contained separated packets of either sensory or motor fibres marked a period of intense interest in the possibility of basing neuro-physiology upon simple laws discoverable by an experimental methodology. Magendie made his fundamental statements on the basis of the apparently unequivocal obliteration of either sensation (after the section of only the posterior roots) or motion (following that of the anterior roots), Magendie F. , “Expériences sur les fonctions des racines des nerfs”, Journal de physiologie expérimentale et pathologie, ii (1822), 276–9; Olmsted translated and quoted this paper in full, op. cit., 100–2. The reliability of these experiments aroused considerable interest and encouraged continual efforts at their repetition and refinement during the nineteenth century. But Magendie's claim of being unaware of the pamphlet printed ten years earlier by Bell generated the dispute over priority with all its rhetorical, methodological, conceptual and nationalistic overtones. In his Idea…, Bell stated that cutting the posterior nerve roots in a stunned rabbit had no visible effect, while stimulating the anterior roots provoked convulsions. In spite of Magendie's steadfast denials, Bell and his supporters insisted that Magendie knew of this work, even if he had not read the pamphlet itself. This dispute has re-emerged repeatedly since the 1820s. Those who have backed Magendie have generally conceded that Bell was doing similar work to his, but in a confused and inconclusive way. Magendie himself allowed, in a conciliatory gesture, that he had perfected the important, if misguided, efforts of Magendie Bell F. , “Expériences sur les fonctions des racines des nerfs qui naissent de la moelle épinière”, Journal de physiologie expérimental et pathologie, ii (1822), 366–71; Flourens P. , “Eloge de F. Magendie” at the Académie des Sciences, Paris (8 February 1855); Bernard C. , De la physiologie générale (Paris, 1872), 15f.; Waller A. , op. cit. Bell's supporters have insisted that Magendie was dishonest in not acknowledging the source of his interest and ideas of spinal nerve function. “Mr Bell on the nervous system”, Edinburgh medical journal, xxv (1826), 106–34; Shaw J. , “An account of some experiments on the nerves; by M. Magendie: With some observations by J. Shaw, Esq., Lecturer on anatomy in Great Windmill-street”, London medical and physical journal, xlviii (1822), 343–52; idem, “Remarks on M. Magendie's late experiments upon the nerves”, London medical and physical journal, lii (1824), 95–104; Todd R. , “Physiology of the nervous system”, in Todd R. (ed.), Cyclopedia of anatomy and physiology (5 vols, London, 1835–59), iii, 720 U. The German literature consistently gave prominence to Bell over Magendie. It tended to see Magendie merely in the flow of ideas from Bell to Müller. See, for example, Remak R. , in Busch (ed.), Encyclopädisches Wörterbuch der medizinischen Wissenschaften, xxv (1841), 159f; also Bickel A. Neuburger M. Eckhard C. , op. cit.; Keith A. , “Charles Bell and the motor and sensory functions of spinal nerves”, The lancet (18 March 1911), 764–5. Conceding that he perfected Bell's probings, they changed the emphasis from “perfected” to “only perfected”. Isolated from its proper setting, and treated as if in a review of the recent literature of a science, their work would seem trivial without the approval of modern neurology implicit in the zealous interest in priority. In this historiographical framework, the distortion becomes so great that we can only make sense of their writings by assuming that they set out to discover the currently accepted law of spinal root function.

Tenon J.-R. Portal A. Sabatier R.-B. Cuvier G. , “Report on a memoir of Drs. Gall and Spurzheim, relative to the anatomy of the brain … presented to, and adopted by the class of Mathematical and Physical Sciences of the National Institute” (15 April 1808), repr. in English translation in Edinburgh medical and surgical journal, v (1809), 36–66. On Gall's work as a background to brain localization and as an alternative to the sensori/motor tradition, see Young R. M. , Mind, brain and adaptation in the nineteenth century (Oxford, 1970), chs i & ii.

See, for example, Flourens P. , Etudes vraies sur le cerveau (Paris, 1863). On the impact of attitudes about the relationship between mind and brain on the study of cerebral localization in the nineteenth century, including the work of Flourens, see Swazey J. P. , “Action proper and action commune: The localization of cerebral function”, Journal of the history of biology, iii (1970), 213–34.

Descartes R. , Discourse on method, sections 4 & 5; idem, Meditations, articles 2, 5 & 6.

Descartes R. , Passions of the soul, articles 31, 32; idem, L'homme , in Oeuvres philosophiques, i, ed. Alquie F. (Paris, 1963), 441f.; Révész B. , Geschichte des Seelenbegriffes und der Seelenlokalisation (Stuttgart, 1917), 161.

Sömmering S. T. , Vom Bau des menschlichen Körpers (in 6 pts, Frankfurt-a.-M., 1791–96), 5th pt, 82–86; Blumenbach J. , Institutions of physiology, 2 vols, trans. from third Latin edn and annotated by Elliotson J. (2nd English edn, London, 1817), i, 125; Révész B. , op. cit. (ref. 9), 189; Ridley H. , The anatomy of the brain (London, 1695), 83–84. Also, see ref. 6.

John Bell Charles , The anatomy of the human body (4 vols, London, 1793–1804), iii, 1, 38.

For an historical review of the concept of the sensorium commune, see Keele K. , Anatomies of pain (Oxford, 1957), ch. iv.

“Is the seat of sensation and will or of the common sensorium, or in other words: the seat of the soul, restricted to a small part of the brain?”, Sömmering S. T. , op. cit. (ref. 10), pt v, 82.

“Besides, whatever might be the seat of the soul; let it reside in an isolated place and all nerves transmit to it the impression of all the objects which strike our sense … or let the soul, spread out everywhere, perceive these impressions at each of the nervous ramifications to which it is tightly bound: No matter; the phenomena of the union of the soul and body will be the same”. Laguerenne , “L'Ame”, Encyclopédie méthodique, Médecine, ii (1790), 126.

Boerhaave H. , “Of the parts and principles of physic”, Academical lectures on the theory of physic, anonymous English translation of the 1708 edition, including Haller's notes (6 vols, London, 1742–46) i, 65–70 (para. 27).

Boerhaave H. , Praelectiones de morbis nervorum (Leiden, 1730–35; repr. with Dutch translation and English summary by Schulte B. , in Lindeboom G. (ed.), Analecta Boerhaaviana (Leiden, 1959)), ii, 256–7. Haller A. adopted the same anatomical definition: See his First lines of physiology, ed. Cullen W. (Edinburgh, 1786; repr. with an introduction by King L. , New York, 1966), xi. 372.

Haller A. , “Moelle allongée”, in Diderot D. D'Alembert J. , Encyclopédie ou dictionnaire raisonné, suppl. iii (Amsterdam, 1777), 942. Forcing an extreme interpretation upon Boerhaave, Julien La Mettrie was one who made a complete identification between the soul and the sensorium. According to Vartanian, Descartes had set this precedent by placing the seat of the soul in the pineal gland, and consequently undermining his distinction between res cogitans and res extensa. “Such speculation”, he added, “indirectly owed a great deal to microanalyses. In laying bare for the first time the extremely complex structures of even the crudest organisms, the microscope had profoundly altered the scientific imagination of the period. As a result, matter seemed to lose much of its classic grossness and, in proportion to the anatomical perfections it displayed, became capable of functions which, owing to their apparent excellence, had traditionally been placed beyond the range of merely material factors”. Vartanian A. , La Mettrie's l'homme machine (ref. 1), 81. My emphasis is somewhat different from Vartanian's. Although matter took on new properties during the eighteenth century and naturalistic explanation intruded into previously sacrosanct domains, concepts of mind retained a powerful influence over the interpretation of brain structure. The postulation and persistence of the sensorium commune expressed just that tension between the power of the concepts of mind and that of an emerging naturalistic explanation consistent with a dynamic and enriched view of matter. Also, see ref. 1.

Jaucourt L. , “Sens interne”, Encyclopédie…, xv (Paris, 1765), 32a.

Newton I. , “Queries” to the Opticks, 4th edn (London, 1730), Qu. 28, 30. In the Whittaker edn (London, 1931; repr. New York, 1952), see pp. 370 and 403; The Leibniz-Clarke correspondence (1705–1716), edited and introduced by Alexander H. (Manchester, 1956), i. 3; ii. 4; iii. 11; iv. 37; Porterfield Wm , Edinburgh medical essays (3rd edn, 6 vols, Edinburgh, 1747), iii, 179–82. I shall discuss further the idea of ‘presence’ later in the paper. Also, see refs 74 and 78.

Bonnet Ch. , Essai analytique sur les facultés de l'âme (Copenhagen, 1760; facsimile repr., Hildesheim, 1973), v.27.

Lamarck J.-B. , Philosophie zoologique (Paris, 1809; repr. Weinheim, Codicote/Herts, New York, 1960), III.i.187.

Lamarck J.-B. , ibid., 176, 177.

“Report on a memoir of Drs Gall and Spurzheim relative to the anatomy of the brain” (see ref. 6).

Ibid., 38 (my own retranslation), also, see Young R. M. , op. cit. (ref. 6), 25; Swazey J. , “Action proper and action commune …”,op. cit. (ref. 7).

Lamarck J.-B. , op. cit. (ref. 21).

Lamarck J.-B. , ibid., 171, 172.

Lamarck J.-B. , ibid., 187; Anthelme Richerand exemplifies the metaphorical power of the sense of “I” in requiring such a centre: “The existence of a central point, at which all sensations are coalesced, from which all movements emanate, is necessary to the unity of the thinking being…”. Nouveaux élémens de physiologie, 3rd edn, 2 vols (Paris, 1804), ii, 147. Richerand (1779–1840) was a prominent member of the Parisian medical world. He held a professorship in pathology at the Ecole de Médecine, and in surgery at the Faculté de Médecine. He was also chief surgeon at the Hôpital de Saint-Louis. Richerand's Nouveaux élémens … was a highly successful text of the early nineteenth century. Between 1801 and 1817, it went through seven editions (Encyclopédie des sciences médicales, Biographie médicale (2 vols, Paris, 1841), ii, 914). The same article stresses his liberal incorporation of Haller's physiology, as does Schiller J. , “Physiology's struggle for independence in the first half of the nineteenth century”, History of science, vii (1968), 64–89.

This ‘phenomenalist’ inclination makes any attempt to brand eighteenth century writers as materialists or spiritualists suspect. See ref. 15; also Bonnet Ch. , op. cit. (ref. 20), 5–6; Diderot D. , Appendix to “l'Ame”, Encyclopédie, i (1751), 340b–2b. “The measure of force exists in its effect, because, although recognized in itself, none of the world's wisdom has ever comprehended the nature of movement itself. We know nothing more of forces than what we learn from experiments.” Haller A. , quoted in Toellner R. (ref. 37), 145; Hall T. , “On biological analogues of Newtonian paradigms”, Philosophy of science, xxxv (1968), 6–27; Cassirer E. , The philosophy of the Enlightenment (Princeton, 1951), 53–56; “The naturalism of La Mettrie, Diderot, Buffon and d'Holbach was fundamentally a means of specifying and vindicating the rightful authority of science to give, by appropriate methods and principles, the completest interpretation of the physical universe within the compass of intelligibility, as such it was primarily, not a dogmatic affirmation that the ‘truth’ about things had at last been found out and all obscurities dispelled, but rather an initial act of intellectual humility… followed by a proposal to search for rationally and empirically verifiable knowledge under conditions that would guarantee the maximum of speculative freedom to the searcher.” The disavowal of metaphysical statements along with the emphasis upon explanation in terms of intelligible principles (e.g., mechanics) and upon the right to unlimited investigation of phenomena characterize the eighteenth-century spirit which Vartanian has called “scientific naturalism”. Vartanian A. , Diderot and Descartes (ref. 1), 311; idem, La Mettrie's l'homme machine (ref. 1), 66–71.

Cuvier G. , “Siège de l'âme”, in Levrault F. G. (ed.), Dictionnaire des sciences naturelles, ii (1804), 34.

Stewart D. , Collected works (ed. Hamilton Wm Sir ; 10 vols + suppl., Edinburgh, 1854), iv, 387–8. Stewart was probably referring to writers like Erasmus Darwin and David Hartley, who extended a physiological model of the nervous system to include the activity of the mind.

Bell Charles Sir , Idea of a new anatomy of the brain (ref. 5), 4. Similarly in Richerand : “All impressions experienced by the sense organs, by the sensory extremities of the nerves, are converged into a single point of the cerebral substance. It is there that the sensorium commune exists …”. Richerand A. , op. cit. (ref. 27), ii, 146–7.

Young Robert Dr has suggested the similarity between my discussion of the sensorium commune as a natural object and Professor Mary Douglas's concept of a natural symbol. In my analysis, the sensorium commune was given its existence by a system of thought which laid down a classificatory grid upon the organism, and in which discrete structures and functions were perceived. The specification of the sensorium was partly anatomical, partly physiological, partly philosophical and partly a representation of other interests which, one might say, it “mediated”. I am only superficially familiar with Professor Douglas's very exciting work, but I find her ideas of the representation of the social order in the control of organic functions and her proposition that “where there is dirt there is system. Dirt is the by-product of a systematic ordering and classification of matter” very suggestive. See Douglas Mary , Natural symbols (Harmondsworth, 1970); idem, Purity and danger (Harmondsworth, 1970). The quotation is from Purity and danger p. 48. For a discussion of these views within the context of structuralist thought: Culler J. , “The linguistic basis of structuralism”, in Structuralism, ed. Robey D. (Oxford, 1973), 20–36.

Cuvier G. , op. cit. (ref. 29), 34–36. Also, see ref. 27. Haller remarked specifically on the inability to trace nerves to a common point, in Diderot D. d'Alembert J. , Encyclopédie, Suppl. iii (Amsterdam, 1777), 945a.

Boerhaave H. Haller A. , see ref. 16; Bordenave T. , Essai sur la physiologie (Paris, 1764), 55–8. Toussaint Bordenave was Professor of Physiology at Saint-Côme, and the French translator of Haller's Elementa…; Sömmering S. T. , Vom Bau… (ref. 10), 83.

Haller A. , op. cit. (ref. 33), 942–5; idem, Anfangsgründe der Physiologie des menschlichen Körpers, translation of the Elementa physiologiae corporis humani by Hallen J. (Berlin, 1768), X. vii–viii. The standard references for the investigation of the brain from Willis to the time of Magendie and Flourens are Neuburger M. , Die historische Entwicklung der experimentellen Gehirn-und Rückenmarksphysiologie vor Flourens (Stuttgart, 1897) and Soury J. , Le système nerveux central: Structure et fonctions: Histoire critique des théories et des doctrines, 2 vols (Paris, 1899).

Buffon G. , Oeuvres complètes, ed. Lanessan J. , 14 vols (Paris, 1885), xi, 128; Cabanis P.-J. , Rapports du physique et du moral (2nd edn, 2 vols, Paris, 1805), i, 211–16; Chaussier F. Adelon N.-P. , “Goût”, Dictionnaire des sciences médicales, xix (Paris, 1817), 42–5; Diderot D. , Elémens de physiologie, critical edn by Mayer J. (Paris, 1964), 88; Dumas C. L. , Principes de la physiologie (4 vols, Paris, 1800), iii, ch. vi; Jaucourt L. , “Tact” in Diderot's Encyclopédie, xv (Paris, 1765), 819b–20a.

A contemporary anonymous English translation entitled A dissertation on the sensible and irritable parts of animals is available with an introduction by Temkin O. in the Bulletin of the history of medicine, iv (1936), 651–99. It was based on the French translation of the original Latin by the prominent Swiss professor of medicine at the College of Lausanne, Tissot S.A.A.D. , which appeared in the first volume of Mémoire de Haller (Lausanne, 1760). For a discussion of Hallerian ‘irritability’ and ‘sensibility’, see Toellner R. , Albrecht von Holler, über die Einheit im Denken des letzten Universalgelehrten (Sudhqffs Archiv, Beiheft x, Wiesbaden, 1971), 171–82, a thorough study of Haller, with a complete bibliography; idem, “Anima et irritabilitas —Hallers Abwehr von Animismus und Vitalismus”, Sudhqffs Archiv, li (1967), 130–44; D'Irsay S. , Albrecht von Haller, eine Studie zur Geistesgeschichte der Aufklärung, Arbeiten des Institut für Geschichte der Medizin, i (Leipzig, 1930), 46–56; Rudolph G. , “Hallers Lehre von der Irritabilität und Sensibilität”, in Rothschuh K. (ed.), Von Boerhaave bis Berger (Stuttgart, 1964; Medizin in Geschichte und Kultur, Bd 5), 14–34.

Haller A. , Dissertation … (ref. 37), 658–9.

Haller A. , Anfangsgründe (ref. 35), X.vii. 13–16; idem, First lines… (ref. 16), xi.365–6.

Haller A. , First lines … (ref. 16), xi. 372; also, see “Moelle allongée” (ref. 17), esp. 945; idem, “Sensibilité”, Encyclopédie, suppl. iv (Amsterdam, 1777), 776a–9b.

These writings, some as letters to Haller, others as papers read to scientific societies, were translated into French and published in three volumes by Tissot. Following a lengthy introduction by Tissot, Haller republished his Dissertation … with additional material including discoveries relating to the sensibility of the brain: Tissot S.A.A.D. , Mémoire de Haller, 4 vols (Lausanne, 1756–60). On the ‘Hallerian school’, see Neuburger M. , op. cit. (ref. 5), 141–66.

“Expériences de M. Housset” in Mémoire de Haller, 2nd edn (Paris, 1762), ii, 315–421. Housset probably planned this work to supply experimental details for Haller's use in an eventual publication, although it is not clear whether or not he was responding to a solicitation. At the beginning of one letter, he asked Haller to “extract all the experiments and … put them into any order which you judge would be the best because I do not wish to impede the printing of your work” (p. 395).

Housset E.-J. , ibid., 360.

Caldani L. , Mémoire de Haller (2nd edn, Paris, 1762), iii, 87. This was the common Hallerian position. See also Bordenave T. , op. cit. (ref. 34), 55–60.

Haller A. , see ref. 40.

Haller A. , First lines … (ref. 16), xi. 372–4; Caldani L. , Physiologie des menschlichen Körpers, trans. Kreuss F. (2nd edn, Prag, 1793), 278.

A system of anatomy and physiology with the comparative anatomy of animals compiled from the latest and best authors…. This text appears to be one of a family of works related through their editor, engraver, and purpose. Fyfe Andrew , an assistant to Monro A. II , was the principal editor and Andrew Bell was the engraver. Later editions were corrected, especially with regard to translation of foreign works, by John Rotherham. I have found editions dated 1784, 1787, 1795 and 1801. Several appeared under the very similar title, A system of anatomy of the human body, also by Fyfe Andrew . I have not compared these two versions. Fyfe and Bell also published two additional series of texts, A compendium of anatomy of the human body and Anatomia Britannica: A system of anatomy and physiology. This family of texts spanned at least the period of 1777–1823 in one of the dominant medical faculties in the world. The plates were partly borrowed, partly original, while the text was probably derivative. The number of editions of the various interrelated series alone suggests that they were very influential and popular. For this paper, I have used the 1784, 1795 and 1801 editions. For the Hallerian view of the brain, see A system (Edinburgh, 1795), ii, 67–75.

Sömmering S. , see ref. 10.

Portal Antoine , Cours d'anatomie médicale, ou élémens de l'anatomie (4 vols, Paris, 1803), iv, 67–68.

de La Peyronie F. , “Observations par lesquelles on tâche de découvrir la partie du cerveau où l'âme exerce ses fonctions”, Histoire de l'Académie des Sciences (Paris, 1741), 199–218. Peyronie La (1678–1747) was first surgeon to the king and one of the founders of the Académie royale de Chirurgie. In this paper, he reported an experiment which was to become quite famous. In a patient with an open head wound which extended down to the corpus callosum, La Peyronie alternately injected and extracted water. With each injection, the patient was rendered unconscious; with each withdrawal, consciousness was restored. Also, see Dufieu J.-F. , “L'Ame”, Dictionnaire raisonné d'anatomie et de physiologie, i (Paris, 1766), 23–40; Diderot D. , d'Alembert's dream, trans. with intro. by Tancock L. (London, 1966), 195.

The dispute in clinical circles was not so much over the criteria, as it was over the specific localization. Thus, the surgeon, Lorry, disputed Vieussens's claim that compression of the corpus callosum produced stupefaction, but not the use of stupefaction as the sign of touching the organ of the soul. It was in the medulla oblongata that one must locate the place of stupefaction. He drew from this work the consequences for the seat of the soul: “It is decided by these experiments that it is the medulla oblongata which is the sole active organ of the brain… “. Reported in Soury J. , Le système nerveux central … (2 vols, Paris, 1899), i, 457–9; also, see Thouret M.-A. , Mémoire de la Société Royale de Médecine, iii (Paris, 1779), 416–68; Laguerenne , Encyclopédie méthodique, Médecine, ii (Paris, 1790), 119–38; and ref. 50. In accordance with his unitary view of the soul and his denial of the localization of faculties, Haller rejected any notion that the destruction of a particular part of the brain might affect a specific faculty. When he did describe the consequences of injuries or disease for mentality, the categories were vague expressions of everyday experience, such as mad (verrückt), raving (toll), and stupid (dumm). Anfangsgründe (ref. 35), X.vii. 22. Sömmering also rejected the localization of faculties (memory, imagination, perception), but he thought that certain kinds of ideas might be the special province of specific parts of the brain, and that pathology could elucidate those relationships: “Carefully observed diseases of the mind combined with exact investigation of the brain can, almost exclusively, throw light here…. But the relevant observations are totally lacking”. The only example he gave referred to the loss of visual ideas after blindness, and thus concerned a sensory deficit more than the mental functions of the brain. So, in fact, Sömmering was thrown back to the sensori/motor procedures of injury and sensibility. Vom Bau des menschlichen Körpers (ref. 10), V. 100; on the surgical study of the brain, see Neuburger M. , op. cit. (ref. 5), 193–213.

Descartes R. , L'homme (ref. 9); idem, Discourse… (ref. 8), section v; Kemp-Smith N. , New studies in the philosophy of Descartes (London, 1963), ch. v, “Descartes's physiological principles as outlined in his Traité de l'homme”.

French R. , Robert Whytt (ref. 4), 138–60; Révész B. , Geschichte des Seelenbegriffes (ref. 9), 180f.; Gusdorf G. , op. cit. (ref. 2).

le Père J.-B. Bouillet , “Faculté vitale”, Encyclopédie, vi (Paris, 1761), 365b–71a; Bordenave T. , Essai sur la physiologie (ref. 34), 55–7; Haller A. , Anfangsgründe (ref. 35), X.vii. 32–39; X.viii. 23, 25. Although Haller dissociated the seat of vitality from that of the soul in his section on the spinal cord (vii.36), his arguments about brain sensibility were thoroughly entwined with examples of brain injury and mortality. His purpose was to show that no one part of the brain was more necessary for survival than any other. Each area, previously a putative centre of life and of the soul, was examined to see if an injury led to sudden death. In each case, he found cases of injury either without effect, or with only a slow death. Thus, he refuted the arguments about the seat of the soul, not by rejecting vitality as a criterion, but by showing that the demonstration of sudden death was in error. (Révész argued that Haller was the first to dissociate the seat of the soul from that of vitality, Geschichte des Seelenbegriffes (ref. 9) 206f.).

Haller A. , Dissertation … (ref. 37), 661–3; 667–8. For centuries, tendon wounds had been feared and surgeons had avoided cutting them. The danger of a tendon wound came to be associated with sensibility through its link with vitality. Thus, when Haller proclaimed the insensibility of tendons, he was not merely raising questions of experimental details and accuracy; he was countering a long medical and philosophical tradition as well. Were it not so, the controversy which raged over the insensibility of tendons and other parts, previously thought to be sensible, would be uninterpretable. On the problem of mortality, sensibility and the surgical tradition, see Lesky E. , “Albrecht von Haller und Anton de Haen im Streit um die Lehre von der Sensibilität”, Gesnerus, xvi (1959), 16–46.

Haller A. , Dissertation … (ref. 37), 668. For brief Statements about wounding and its ambiguities, see his First lines… (ref. 16), xi. 370–1. See also Caldani's L. letter to Haller , in Mémoire de Haller (2nd edn, Paris, 1762), iii, 80. Prejudiced by the pre-Hallerian view of the brain and of dural sensibility, he reacted to brain stimulation experiments which produced convulsions, by saying: “Would you believe that I still did not make anything of this experiment? Being so prejudiced in favour of the insensibility of the brain, I doubted that I had not touched the membrane which I believed to be the only site capable of producing all these accidents …”.

Haller A. , Dissertation … (ref. 37), 663.

Haller A. , Anfangsgründe (ret 35), X.vii. 21.

This reaction figured prominently in Whytt's Observations on the sensibility and irritability of the parts of men and other animals, in his Works of Robert Whytt published by his son (Edinburgh, 1768), esp. 270f.

Petrini P. J. , extracted in Mémoire de Haller (2nd edn, Paris, 1762), ii, 279; also Housset's letter to Haller in same series: ii, 366.

Windelband W. , A history of philosophy, transl. by Tufts J. (2 vols, New York, 1901, repr. 1958), ii, 437f.; Cassirer E. , Philosophy of the Enlightenment (ref. 28), 115f.; Gay P. , The Enlightenment (ref. 3), ii, 150–215.

Locke J. , An essay concerning human understanding, edn of Fraser A. (2 vols, London, 1894), Introduction, 26–27; for an overall study of Locke and his work, see Aaron R. , John Locke (3rd edn, Oxford, 1971).

The growth of physiological ideas within the sensualist philosophical tradition can be clearly traced in French thought: Condillac, Tracy, Cabanis, Richerand and Magendie. Condillac set out to write a critique of Locke's Essay; Tracy and Cabanis developed Condillac's ideas, Cabanis elaborating a physiological model of sensation. Richerand and Magendie, writing for a physiological and medical audience, explicitly elaborated the views of Condillac Tracy Boas Cabanis. G. , French philosophies of the Romantic period (Baltimore, 1925), chs i and ii; Temkin O. , “The philosophical background of Magendie's physiology”, Bulletin of the history of medicine, xx (1946), 10–35; Young R. , Mind… (ref. 6), 81–88, refers to Magendie and this tradition; the standard reference is Picavet F. , Les Idéologues. Essai sur l'histoire des idées et des théories scientifiques, philosophiques, religieuses, etc., en France depuis 1789 (Paris, 1891). I shall draw upon this tradition without specific reference to the French adaptation of Lockean philosophy.

The separation of mind from body was a theological assertion about the immortal soul, and an epistemological one about the forms of intelligibility (mental and physical). In Descartes's mind, the arguments about dualism were philosophical/theological, not physiological. The union of body and soul was a primary datum, for which there was a set of clear ideas, i.e., ideas inseparable from our own bodies, but distinct from those of any other bodies (such as hunger and thirst). In the Cartesian tradition, however, the physiological/psychological and the philosophical/theological levels were conflated. Thus, while it may be inaccurate to treat Descartes's dualism in terms of the impossibility of unmediated interaction between mind and body, it is reasonable to discuss Cartesian dualism (i.e., the tradition) in this way. On this point, see Beck L. , The metaphysics of Descartes (Oxford, 1966), 269–76. For a compilation and discussion of the relevant passages of Descartes on this theme, see Kemp-Smith N. , New studies … (ref. 52), 139–60.

In this section, I am using ‘mediate’ in its traditional sense—that of interposing in order to form a connecting link or a unification.

Descartes R. , Passions of the soul (ref. 9), article 31; idem, L'homme, in Oeuvres, i (ref. 9), 441f. Although Descartes used this sort of suggestive language, he also said that the mind could perceive directly the representations patterned by the nervous system on the brain. This is another example of the natural unity of mind and body, even though they were ontologically distinct. See Kemp-Smith N. , New studies … (ref. 52), 146–7.

“It is evident that a body, that of extension, purely passive substance, cannot act by its own action on a spirit, on a being of another and infinitely more excellent nature than it. Thus, it is clear that in the union of soul and body there is no other connection than the efficacy of divine decree. God has willed, and he wills without cessation, that the diverse commotions of the brain be always followed by diverse thoughts… and it is this constant and efficacious will of the Creator which, in fact, causes the union of these two substances ….” Malebranche N. , Lumière et mouvement de l'esprit (Textes choisis, Bibliothèque Classique de Philosophie, Paris, 1962), 12. “They perceive what passes without them, by what passes within them, answering to the things without: In virtue of the harmony that God has pre-established ….” Leibniz G. , Leibniz-Clarke correspondence, op. cit. (ref. 19), letter 5, article 87; Brett G. , History of psychology (edn of Peters R. , Cambridge, Mass., 1962), pt iii, ch. xi. With respect to the problem of the certainty of knowledge of the external world, see Windelband W. , op. cit. (ref. 61), 466–86.

Cassirer E. , op. cit. (ref. 28), 97f.

Windelband W. , op. cit. (ref. 61), 447–66.

Locke J. , Essay … (ref. 62), II.i. 2–4.

Aaron R. , John Locke (ref. 62), 99–115. Locke did not use the word ‘presence’. That objects could impress ideas on the mind directly was, however, clear in his Essay.… For those who were concerned with the problems of mind/body interaction, the idea of ‘presence’ was crucial. The use of this concept will be discussed below. Locke J. , Essay … (ref. 62), II.viii. 7–8.

Locke J. , op. cit. (ref. 62), II.viii. 11–26; Aaron R. , John Locke (ref. 62), 118–19.

Boyle R. , “The origins of forms and qualities”, Works, ed. Birch T. (6 vols, London, 1772), iii, 36; Aaron R. , John Locke (ref. 62), 121–3. On Locke's realism, and on the relationship between primary and secondary qualities in Locke, Boyle and Newton, see Mandelbaum M. , Philosophy, science and sense perception (Baltimore, 1964), chs i and ii.

Locke J. , Essay … (ref. 62), II.viii. 12.

Newton I. , Opticks (ref. 19), Qu. 28. “… [God] is no more the Soul of [the world], than the Soul of Man is the Soul of the Species of Things carried through the Organs of Sense into the place of its Sensation, where it perceives them by means of its immediate Presence, without the intervention of any third thing…”, Qu. 30, p. 403; Kemp-Smith N. , New studies… (ref. 52), 146–7, fnt. i. For an elaboration on the same theme, see Clarke's S. letters to Leibniz in the Leibniz-Clarke correspondence (1705–1716) (ref. 19); also, see ref. 74.

Newton I. , op. cit. (ref. 19), Qu. 12, 23, 24.

Hartley David , Observations on man, his frame, his duty, and his expectations (2 vols, London, 1749), i. 7.

Hartley D. , ibid., 16.

Adelon N.-P. , Physiologie de l'homme (4 vols, Paris, 1823–24), i, 229–36; Haller A. , Anfangsgründe (ref. 35), X.vi. 6–8; X.viii. 2–18; idem, Dissertation … (ref. 37), 670; idem, First lines … (ref. 16), xi. 376–82; de la Roche D. , Analyse des fonctions du système nerveux (Geneva, 1778), ii, 291–320; Prochaska G. , A dissertation on the functions of the nervous system (Vienna, 1784; transl. Laycock Th. , London, 1851), ch. i, sect. 7; ch. iii, sect. 1; Blumenbach J. F. , Institutions… (ref. 10), xii. 222–6; Carlson E. Simpson M. , “Models of the nervous system in eighteenth century psychiatry”, Bulletin of the history of medicine, xliii (1969), 101–15.

Haller A. , First lines … (ref. 16), xviii. 56.

Haller A. , ibid., xviii. 57.

Haller A. , ibid., xviii. 64, 70. The passivity of the mind, even in acts of will, was characteristic of the sensualist tradition. For Magendie, see Young R. , Mind … (ref. 6), 81–88.

Locke J. , Essay … (ref. 62), II.viii. 12–15; IV.iii. 16; also, see ref. 73.

Haller A. , ibid., xviii. 58.

Prochaska G. , A dissertation … (ref. 79), ch. ii, sect. 3; ch. v.

Richerand A. , Nouveaux élément … (ref. 31), ii (1804), 156f.

Richerand A. , ibid., 148.

Richerand A. , ibid., 149.

Ibid. (ref. 31). See above, p. 185.

See ref. 36, and above, p. 186.

Buffon G. , Works (ref. 36), xi, 127–9.

Jaucourt L. , “Tact”, Encyclopédie, xv (1765), 819b–20b.

Cabanis P.-J. , Rapports. (ref. 36), i, 211; Cuvier G. , Leçons sur l'anatomie comparée (5 vols, Paria, 1805), ii, 426; Dumas C. , Principes… (ref. 36), chs 6, 7; Garnett T. , Popular lectures on zoonomia or the laws of life (London, 1804), 11; Montfalcon , “Sens”, Dictionnaire des sciences médicales, li (1821), 28; Richerand A. , Nouveaux élémens … (ref. 27), ii, 63. Although touch as the architypal passive sensory mode dominated the physiological literature, another current was developing in the philosophical, psychological, and some of the physiological literature. In this case, touch was the active, intellectual sense by which the mind divided itself from its surroundings and constructed an external reality: “Many animals are superior to [man] with respect to movements and the four senses of taste, smell, hearing and vision. But notice that he outstrips them completely by the perfection of the fifth sense, touch. Why? Because this sense is totally different from the others, because it follows them, and corrects their errors. We touch, because we have seen, understood, tasted and felt objects. This sense is voluntary; it supposes reflection in the animal using it, unlike the others [which] do not require [reflection]”. Bichat X. , Anatomie générale (2nd edn, 4 vols, Paris, 1812), i, 117–18. Also, see Smith R. , “The background of physiological psychology…” (ref. 1), 88–101. I share Dr Smith's emphasis upon the importance of this theme and agree with him that it needs a thorough investigation.

Bell Charles Sir , Idea … (ref. 5), 4.