7月GMAT阅读考古题-第8篇网上资料

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The Functions of the Brain:
Gall to Ferrier (1808-1886)

By Robert M. Young*

THE BIOLOGICAL SCIENCES and particularly psychology have been made the wastebasket of the scientific revolution. In his classical discussion of The Metaphysical Foundations of Modern Physical Science, E. A. Burtt referred to the concept of mind as a convenient receptacle for the refuse, the chips and whittlings of science, rather than a possible object of scientific knowledge.l A. G. A. Balz made the same point in his Cartesian Studies, where he noted that psychology "had to be whatever the new physics and the related metaphysics permitted it to be."2 A diagnosis of the limitations of the explanatory model of the scientific revolution has been made many times. The writings of Burtt and of A. N. Whitehead are but two examples of penetrating discussions of the difficulties involved in attempting to include biology, psychology, and the social sciences in the explanatory paradigm of the physical sciences.3 The prescriptions provided by these same authors show just how far we are from providing an alternative. It is arguable that a pre requisite to useful reconstructive work to repair what Burtt called "a rather radical piece of cosmic surgery"4 is at least a generation of careful historical research.5 In spite of Edwin G. Boring's admirable pioneer studies, this work has not yet begun.6
        Speaking of the seventeenth-century metaphysician-scientists, Burtt asks,

Did it never cross their minds that sooner or later people would appear who craved verifiable knowledge about mind in the same way they craved it about physical events, and who might reasonably curse their elder scientific brethren for buying easier success in their own enterprise by throwing extra handicaps in the way of their successors in social science?7

Cartesian dualism and the doctrine of primary and secondary qualities enabled the physical sciences to develop, but this was achieved at the expense of the biological and behavioral sciences. The present study is an attempt to trace some of the im-

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* Whipple Science Museum, University of Cambridge. (For current address, see end of article.)
1 E. A. Burtt, The Metaphysical Foundations of Modern Physical Science (2nd ed., London: Routledge & Kegan Paul, 1932), p. 319.   
2 A. G. A. Balz, Cartesian Studies (New York Columbia Univ. Press, 1951), p. 196.   
3 Alfred North Whitehead, Science and the Modern World (Cambridge: Cambridge Univ. Press, 1925), Chs. 3, 6, 9.
4 Burtt, Metaphysical Foundations, p 302.   
5  See my essay review on "Philosophy of Mind and Related Issues" in British Journal for the Philosophy of Science 1967 18: 325 330.
6 Cf. Robert M. Young, "Scholarship and the History of the Behavioural Sciences," History of Science, 1966, 5: 1-51.   
7 Burtt, Metaphysical Foundations, pp. 31 319.


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plications of this world view in the scientific writings of psychologists and neurophysiologists in the nineteenth century. This topic was chosen because the relations among brain, mind, and behavior seem to be the obvious and crucial area for investigating the limitations of Cartesian dualism as applied to the biological sciences. It seems clear at the outset that the major difficulty of those who did crave verifiable knowledge about the mind was that they were very slow and timid about cursing their elder scientific brethren. By Cartesian dualism is meant, of course, the conception of two ontological substances: matter, which is extended, divisible, passive, and law-like; and mind, which is unextended, indivisible, active, and free. These substances were defined in such a way that any relationship between them seemed impossible in a metaphysical sense. The psychologists and physiologists were left with the problem of explaining how, in fact, impressions on the sense organs caused ideas, and thoughts caused movements, that is, how interaction occurred when it was metaphysically inconceivable.
        Mind-body dualism played an important part in the period when attempts began to be made to apply the categories of science to the study of mind and brain. If attention is restricted to empirical investigation of these issues, one must begin in the nineteenth century, with the work of Franz Joseph Gall (1758-1828). After his doctrine has been considered, its relations with three other traditions will be outlined: first, the association psychology; second, the application of the categories of sensation and motion to progressively higher parts of the nervous system; third, a changing context for psychology, from a primarily philosophic approach within the static framework of the great chain of being to a biological approach based on the dynamics of evolutionary change. Thus, when the psychological principle of association was combined with the physiology of sensation and motion and integrated into a sensory-motor psychophysiology, this unified doctrine was almost immediately reinterpreted in terms of the theory of evolution as applied to mind and brain and to the relations between organisms and their environments. The body of the paper is concerned with a closely interrelated set of influences extending from early empirical studies on mind and brain to the establishment of experimental research on this topic. My aim is to suggest that when the study of the mind came to be considered in physiological and biological terms, powerful philosophic constraints were at work which narrowed the issue and impoverished the study of the mental functions of human and other organisms.
        These developments occurred in the course of debates about the principle of cerebral localization, which may be defined as the doctrine that various parts of the brain have relatively distinct mental, behavioral, and physiological functions. For example, it is generally believed that the forebrain subserves intellectual functions, that just behind that is an area for the control of muscular movements, and that beneath the motor areas are a number of structures which regulate metabolic functions. Speculative localizations of functions date from Herophilus and Galen, that is, from the beginnings of anatomy and physiology. Various schemes of cerebral localization were proposed before the nineteenth century; for example, in the sixteenth century Gregor Reisch localized sensation, imagination, reasoning, and memory in the ventricles of the brain.8 After attention was shifted from the ventricles (and the associated pneumatic physiology) to the solid parts of the brain, the same faculties were variously localized.9
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8 H. W. Magoun, "Early Development Ideas Relating the Mind with the Brain," in G. E. W. Wolstenholme and C. M. O'Connor, eds., Neurological Basis of Behaviour (London: Churchill, 1958), p. 16.
9 A. Macalister, "Phrenology," in The Encyclopaedia Britannica (9th ed., Edinburgh: Black, 1885), Vol. XVIII, pp. 842-849; Jules Soury, Le Système nerveux central: structure et fonctions: histoire critique des théories et des doctrines (Paris: Carre & Naud, 1899), Vol. I; F. N. L. Poynter, ed., The History and Philosophy of Knowledge of the Brain and Its Functions (Oxford: Blackwell Scientific Publications, 1958).


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        The work of Franz Joseph Gall provides the first empirical approach both to the nature of the faculties and to their localizations.10 The prevailing view just before Gall began his researches can be gathered from George Prochaska's Dissertation on the Functions of the Nervous System, published in Vienna in 1784, twelve years before Gall took his medical degree there. Prochaska argued that cerebral localization was probably valid, that the relevant faculties were the understanding, the will, imagination, and memory, but that "the conjectures by which eminent men have attempted to determine these are extremely improbable, and that department of physiology is as obscure now as ever it was;...''1l It is noteworthy that in 1799 Bichat still maintained confidently that the brain was the seat of the intellect but not of the passions.12 Gall insisted that the brain was the physiological basis of all mental functions.
        Gall's ideas developed from childhood observations of his playmates. Those who could memorize better than he, had bulging eyes.l3 This was merely a physiognomical correlation, with no apparent physiological basis. Gall extended the correlation in two ways. First, he based it on a doctrine about the brain: bulging eyes were caused by a large underlying brain area for the faculty of verbal memory.14 Second, he argued that this faculty was innate — thus opposing the prevailing sensationalism of the idéologues.15 He generalized these points to argue that a science of human nature could be founded on four types of variables:

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1                                    2                            3                             4
STRIKING BEHIAVIOR   implies   FACULTY   implies   CORTICAL   implies    CRANIAL
                                                                              ORGAN                    PROMINENCE
                                                                                          
                              causes                         causes                         causes

(talent, propensity,                (innate                         (activity                (size varies                     mania)                                instinct)                 varies                 with under-
                                                                with size)                     lying organ)

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lO Francois Joseph Gall and J. C. Spurzheim, Anatomie et physiologie du système nerveux en général et du cerveau en particulier avec des observations sur la possibilité de reconnaître plusieurs dispositions intellectuelles et morales de l'homme et des animaux par la configuration de leurs têtes, 4 vols., with an atlas of 100 engraved plates. (Paris: Schoell, 1810-1819). (Gall is sole author of Vols. III and IV.) Gall, Sur les fonctions du cerveau et sur celle de chacune de ses parties 6 vols. (Paris: Ballière, 1822-1825). Gall, On the Functions of the Brain and Each of Its Parts: With Observations on the Possibility of Determining the Instincts, Propensities and Talents, or the Moral and Intellectual  Dispositions of Men and Animals, by the Configuration of the Head, trans, Winslow Lewis, Jr., 6 vols. (Boston: Marsh, Capen & Lyon, 1835). Gall, et al., On the Functions of the Cerebellum by Drs Gall, Vimont, and Broussais, trans. George Combe (Edinburgh: Maclachlan & Stewart, 1838).   
1l George Prochaska, A Dissertation on the Functions of the Nervous System, trans. Thomas Laycock (London: Sydenham Society, 1851), pp. 446, 447.   
12 Xavier Bichat, Physiological Researches on Life and Death, trans. F. Gold (London: Longmans, n.d.), pp. 62, 252.   
13 Gall, On the Functions of the Brain, Vol. I, pp. 57-58.   
14 Ibid., p. 59.   
15 Ibid., pp. 80-83, 95-171. See also Pierre J. C. Cabanis, Rapports du physique et du moral de l'homme, 2 vols. (2nd ed., Paris: Crapart, Caille & Ravier, 1805); François Picavet, Les Idéologues (Paris: Alcan, 1891); George Rosen, "The Philosophy of Ideology and the Emergence of Modern Medicine in France," Bulletin of the History of Medicine, 1946, 20 : 328-339; George Boas, French Philosophies of the Romantic Period (Baltimore: Johns Hopkins Press, 1925), Chs. 1 and 2; Madison Bentley, "The Psychological Antecedents of Phrenology," Psychological Monographs, 1916, 21: 102-115; Owsei Temkin, "The Philosophical Background of Magendie's Physiology," Bull. Hist. Med., 1946, 20: 10-35; Temkin, "Gall and the Phrenological Movement," Bull. Hist. Med., 1947, 21: 275-321 (on the idéologues, see esp. pp. 289-299). Temkin's article on Gall is the best secondary source available on this subject.

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        Given this paradigm, Gall argued that the then-prevailing categories of interpretation — intelligence, reason, will, and so forth — were wholly inadequate to account for the obvious behavioral differences among species and individuals.l6 Where these categories stressed the relations between minds and objects for knowledge, Gall emphasized the adaptation of organisms to their environments.17 As he put it, "every hypothesis which renders no reason for the daily phenomena which the state of health and the state of disease offer us, is necessarily false.''l8 He argued that "the most sublime intelligence will never be able to find in a closet, what exists only in the vast field of nature.''l9 The implication was that psychology is not a branch of epistemology, but of general biology, and he devoted himself to making comparisons among the striking talents of men, the different habits and abilities of different species, and the compilation of a truly natural classification of functions.
        Gall's findings and his influence played a seminal role in neuroanatomy and in the development of the concept of cerebral localization in neurophysiology and neurology,20 but in his own work it was undermined by his belief in "bumps" as accurate reflections of the relative size of areas of the underlying brain. This is only one example of a principle which Gall stated but which he was unable to carry out in practice. He established once and for all that the brain is the organ of the mind. Even Pierre Flourens, Gall's arch-opponent, granted this.2l His naturalist viewpoint, coupled with his critique of philosophical psychology, played an important part in removing psychology from philosophy and placing it in biology. Most important, however, was his argument that neither the study of the physiology of the brain nor the introspective study of mind would alone provide adequate categories for interpreting experience and behavior. Comparative studies of animals and observation of man in society — particularly the extraordinary (geniuses and maniacs)—were the essential prerequisites for arriving at a psychology which might explain mind, brain, and behavior.22
        There is no reason to dwell on Gall's methods or the final formulation of his psychology.23 One concludes from a study of his large compendium of evidence for his faculties that the phrenological method is a textbook case in support of a falsificationist view of scientific method, for he sought confirmations and failed to take exceptions seriously enough.24 One should emphasize the value of his naturalist,
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16 Gall, On the Functions of the Brain, Vol. I., pp. 88-89.
17 Ibid., p. 84.
18 Ibid., Vol. V, p. 251
19 Ibid., p. 317.   
20 Erwin H. Ackerknecht and Henri V. Vallois, Franz Joseph Gall, Inventor of Phrenology and His Collection, Wisconsin Studies in Medical History, No. 1 (Madison: Univ. Wisconsin Press, 1956), pp. 13-27. For Gall's contributions to neuroanatomy, see Owsei Temkin, "Remarks on the Neurology of Gall and Spurzheim," in E. A. Underwood, ed., Science, Medicine and History  (London: Oxford Univ. Press, 1953), Vol. II, pp. 282-289.   
21 Pierre Flourens, Phrenology Examined, trans. Charles Meigs (Philadelphia: Hogan & Thompson, 1846), pp. 27-28.   
22 Gall, On the Functions of the Brain, Vol. III, pp. 133-135; Vol. IV, p. 162.   
23 Gall discusses his methods in ibid., Vol. III, pp. 108-130.   
24 This article is primarily concerned with the ways in which phrenology influenced developments in psychology and the study of the nervous system. A most interesting study of the parallel development of the phrenological movement in Britain, France, and America in this same period could provide a counterpoint to my rather Whiggish emphasis on the "winning side." For criticism of the cranioscopic method see Richard Chevenix, "Gall and Spurzheim—Phrenology," Foreign Quarterly Review, 1828, 2: 1-52; William Carpenter, "Noble on the Brain and Its Physiology," British and Foreign Medical Review, 1846 22: 488-544 (esp. pp. 520 ff. ); George H. Lewes, "Phrenology in France," Blackwood's Edinburgh Magazine, 1857, 32: 665-674. The reactions of phrenologists to criticism can be judged from reading almost any article in the Phrenological Journal. See also the list of phrenological controversies appended to Gall et al., On the Functions of the Cerebellum. The history of scientific physiology and psychology parted company with the practice of phrenological delineation (popularly known as "head-reading") over the legitimacy of the cranioscopic method. The history of applied phrenology formed an important part of the development of the scientific study of man by virtue of its wide popularity and its influence on Robert Chambers, A. R. Wallace, and Auguste Comte, among others. The American movement has received some attention. See John D. Davies, Phrenology Fad and Science: a 19th Century American Crusade (New Haven: Yale Univ. Press, 1955); David Bakan, "The Influence of Phrenology on American Psychology," Journal of the History of Behavioral Sciences, 1966, 2: 200-220. The British movement would repay closer study. There is a very large literature, and the influence of phrenology on evolutionary theory, various forms of social reform, and the behavioral sciences is very interesting indeed. In 1820 George Combe helped to found a phrenological society in Edinburgh and became its first president. By 1832 there were 29 phrenological societies in Britain and several journals in Britain and America. Their publications provide a most illuminating perspective on contemporary scientific developments. The British Phrenological Society was incorporated in 1899. It continued to publish a newsletter until 1966. The Society functioned until February 1967, when it went into voluntary liquidation. Its past president, Miss Frances Hedderly, F.B.P.S., has guided its affairs over the last few years and is now convinced that the work of the Society is completed. Its valuable library has been deposited at University College, London, and at the Whipple Science Museum, Cambridge. My research has been aided in many ways by the co-operation of Miss Hedderly and other members of the Society.

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biological approach in psychology but grant that the conclusions he drew invited the criticism which has been earned by all faculty psychologies: they substitute classification for explanation.25 To explain that a mother loves her child because she has a large cerebral organ producing a strong faculty of "philoprogenitiveness" is on a level with Molière's physician who explained the action of opium by invoking a "soporific virtue."26
        Gall's anecdotal and correlative methods and his faculty psychology can serve only as object lessons in the misuse of scientific method. However, the obvious alternative — experiment — had failed to produce significant advances in understanding the functions of the nervous system until 1822, six years before Gall died.27 In his critique of the experimental method, Gall pointed out that it was difficult to repeat findings or to make inferences based upon, for instance, the sexual performance of an animal which was rapidly ceasing to live from uncontrollable loss of blood.28 However, these objections were rapidly overcome by technical and methodological developments, and one's claims for Gall are confined to the principles
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25 For criticisms of faculty psychologies see Carroll C. Pratt, "Faculty Psychology " Psychological Review, 1929, 36: 142-17; George F. Stout, "The Herbartian Psychology," Mind, 1888, 13: 321-338 and 473-498 and Stout, "Herbart Compared with English Psychologists and with Beneke," Mind, 1889, 14: 1-26; Charles E. Spearman, The Abilities of Man: Their Nature and Measurement  (London: Macmillan, 1927), pp. 28 ff.   
26 Cf. Galen: ". . . so long as we are ignorant of the true essence of the cause which is operating, we call it a faculty." On the Natural Faculties, trans. A. J. Brock (London: Heinemann, 1963), p. 17.   
27 Pierre Flourens, Recherches experimentales sur les propriétés et les fonctions du système nerveux dans les animaux vertebrés (Paris: Crevot, 1824); J. M. D. Olmsted François Magendie (New York: Schuman's, 1944), Ch. 7.   
28 Gall, On the Functions of the Brain Vol. III, p. 257. Cf. ibid., pp. 97-100 and 240-263; Vol. VI, pp. 153 and 239.

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mentioned in the preceding paragraphs and his prediction that the physiological experimenters ran the danger of reducing mental life to sensibility, irritability, and muscular motion.29 It will become apparent that he was most prescient.
        In the experimental work which began to give significant results in 1822, the most important early sensory-motor physiologists were Pierre Flourens, François Magendie, and Johannes Müller. Their methods and some of their findings were very elegant indeed, but their analyses of the "organ of mind" were highly conditioned by their philosophical preconceptions. Flourens' careful methods of excision, control of bleeding, and observation of animals over long periods led to his classical findings on the regulatory functions of the cerebellum in muscular co-ordination and his location of the respiratory center in the medulla oblongata.30 Magendie demonstrated by experiment that the anterior spinal nerve roots are motor in function and the posterior roots are sensory. (The functional division between the anterior and posterior spinal nerve roots came to be known as the Bell-Magendie law, since Bell reached the same conclusion on anatomical grounds.31) Johannes Müller confirmed and extended these findings, and they were widely read in his classical Handbuch.32 In the period between 1822 and 1845 these three men were the leaders in establishing the experimental method in neurophysiology. Their work was a continuation of the investigation of physiological properties which was begun by Francis Glisson and made experimental by Albrecht von Haller.33 The discoveries which von Haller had made about the properties of the peripheral nerves they extended to the spinal cord and some higher centers. Furthermore, they adopted the paradigm of explanation — sensation and motion — which was to be progressively used to account for all nervous functions.   
        It is when one turns to the brain that the influence of philosophic constraints on their approach becomes apparent. Flourens' experiments on the brain involved successive slicing of the cortical substance without reference to the alleged cortical organs. Even if Gall's localizations had been true, this technique could only lead to successive loss of all functions.34 Flourens concluded that the cortex acts as one organ and that all its supposed faculties are indivisible. Thus the lower centers were for sensation and motion, while the cortex was a unitary organ for a unitary mind.35 The basis of this view is clear from the dedication of his Examen de la Phrénologie: "I frequently quote Descartes: I even go further; for I dedicate my work to his memory. I am writing in opposition to a bad philosophy [Gall's], while I am endeavoring to recall a sound one."36 It should be stressed that while Flourens'
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29 ibid., Vol. VI, pp. 160-161; cf. Vol. III, p. 245.
30 Flourens, Recherches expérimentales (2nd ed., Paris: Ballière, 1842). See also J. M. D. Olmsted, "Pierre Flourens," in Underwood, ed., Science, Medicine and History, Vol. II, pp. 290-302.
31 Olmsted, François Magendie, Ch. 7.
32 Johannes Müller, Elements of Physiology, trans. W. Baly, 2 vols. (London: Taylor & Walton, 1838-1842), Vol. I, pp. 640-646; cf. John T. Merz, A History of European Thought in the Nineteenth Century, 4 vols. (Edinburgh: Blackwood, 1904-1912), Vol. II, p. 384n.
33 Albrecht von Haller, "A Dissertation on the Sensible and Irritable Parts of Animals" (1735), trans. M. Tissot, reprinted with an introduction by Owsei Temkin, Bull. Hist. Med., 1936, 4: 651-699. Cf. Temkin, "The Classical Roots of Glisson's Doctrine of Irritation," Bull. Hist. Med., 1964, 37: 297-328. On the relationship between the concepts of Glisson, Haller, and Flourens, see Anon., "Recent Discoveries on the Physiology of the Nervous System," Edinburgh Medical and Surgical Journal, 1824, 21: 141-159, p. 144.   
34 Gall, On the Functions of the Brain Vol. VI, pp. 164-166; Vol. III, p. 244.   
35 Flourens, Recherches experimetales (1842), pp. xvi, 97, 208, 235, 243-244.  
36 Flourens, Phrenology Examined, p. xiv; cf. pp. xi, xiii, 38, 45, 53, 57, 96.

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findings were not inconsistent with his interpretation of them, some of his extreme claims — for example, that the cortex is not the origin of any nerve — cannot be reconciled with the state of contemporary knowledge without allowing a large role for preconception.37 In the light of Gall's injunctions it is interesting to note that neither Flourens nor Magendie nor Müller — for all their emphasis on observation and experiment — made any attempt to determine the categories of function. They reverted to such traditional ones as memory, reason, and will.   
        Magendie's initial remarks about the brain were more promising: its study was a branch of physiology like the study of the functions of any other organ.38 However, when he specified what he meant by "physiology" in this context, a hiatus appeared, for the study of the physiology of the brain was identified as idéologie —  the sensationalist analysis of mind which grew out of the work of Locke and Condillac and was then represented in Paris by Destutt de Tracy and Cabanis.39 These assumptions were, of course, different from Flourens' Cartesianism, but one result was the same: the analysis of the brain was separated from that of the lower centers. Will became a species of desire in the philosophy of the idéologues, but its cerebral basis was not directly connected with the cause of muscular contraction.40 Furthermore, the method used in this supposedly "physiological" investigation was introspection.4l
        Müller, like Flourens and Magendie, rejected cerebral localization and the categories of Gall and separated the organs of mind from motor functions.42 As he put it in his Handbuch, "The fibres of all the motor, cerebral and spinal nerves may be imagined as spread out in the medulla oblongata, and exposed to the influence of the will like the keys of a piano-forte." It was impossible to determine how an exertion of the will excites these fibres.43
        There is little point in multiplying examples of this separation except to emphasise that it became the accepted account. The standard British text, William Carpenter's Principles of Physiology, reiterates it through all editions, and he expounds it in his other writings right up to and including his review of the experiments of David Ferrier which decisively disproved it.44 The cortex was a unitary organ, "superadded" to the sensory-motor centers. The latter were said to be the instruments of the mind, and the mind's cortical organ had no connection with purely excito-motor actions.45 The motor aspect of this orthodoxy has been nicely summarized by Sir Geoffrey Jefferson:

From Haller . . . onwards to the best observer of them all, Flourens, and on again to Magendie and everyone else, all were agreed upon this, the brain was unresponsive except at the lower and lowest levels. The hemispheres were the seat of the "will"; they excited movements by playing on these motor mechanisms. But how they did so no one knew and no nice man would ask !46
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37 Flourens, Recherches expérimentales (1842), pp. xiii, 19, 22, 50, 237-239.
38 François Magendie, An Elementary Treatise on Human Physiology, trans. John Revere (5th ed., New York: Harper, 1843), p. 146.
39 Ibid., p. 147. See also references cited above, n. l5.
40 Ibid., pp. 151, 243-246, 252-253.   
41 Ibid., p. 146.   
42 Müller, Elements of Physiology, Vol. I, pp. 834-838, Vol. II, p. 1345; Flourens, Phrenology Examined, passim; Magendie, Elementary Treatise, p. l5On.
43 Müller, Elements of Physiology, Vol. II, p. 934.
44 William Carpenter, Principles of Mental Physiology (London: King, 1874), pp. 99-100, 715, 719.
45 Carpenter, "Noble on the Brain" pp. 5OO, 510-512, 515; Principles of Human Physiology  (5th ed., Philadelphia: Blanchard & Lea, 1855), pp. 534-535, 489-490, 497-511.
46 Geoffrey Jefferson, Selected Papers (London: Pitman Medical, 1960), p. 116.

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        We are left therefore with precise findings about the sensory-motor function of the spinal roots and some higher structures and an unphysiological doctrine about the cortex. When science has an unequivocal theory in one area and confusion in another, it is natural that an attempt will be made to extend the former to account for the latter. What was needed for the full exploitation of the sensory-motor paradigm of Bell and Magendie was a suitable theoretical context for bringing it into contact with psychology.
        The theoretical context for sensory-motor physiology was provided by Alexander Bain. Bain was the heir to a psychological tradition which grew out of Locke and Gay,47 whose anti-Cartesian sensationalism was united with Newton's corpuscular theory of matter to provide the basis of the association psychology, first clearly formulated by David Hartley.48 The associationists specified atomic units for what Descartes considered to be indivisible mental substances. They argued that all complex mental phenomena could be analyzed into sensations and that the larger mental elements were built up by habit or repetition — the law of association.49
        Association psychologists prior to Bain had seen their work in a philosophic context. Bain wrote psychology free from formal philosophy and set out to integrate the science of mind with physiology. In the Preface of the first volume (The Senses and the Intellect) of his major work he wrote, "Conceiving that the time has now come when many of the striking discoveries of the Physiologists relative to the nervous system should find a recognised place in the Science of Mind, I have devoted a separate chapter to the Physiology of the Brain and Nerves."50 He developed this approach on the basis of an early interest in phrenology before he was exposed to the influence of associationism through his relationship with John Stuart Mill.5l  This mixture of influences led him to stress physiology but to abandon the faculty psychology of phrenology in favor of the principle of association and to reduce the phrenological faculties to, for example, ocular sensibility.52 He first reduced the numerous faculties to three — intellect, feelings, and will — and then analyzed these into associated sensations and motions. His chapter on the  nervous system applied the sensory-motor paradigm to subcortical structures but stopped short of the hemispheres.53 Drawing on the work of Todd and Bowman,
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47 John Locke added a chapter entitled "Of the Association of Ideas" to Book 2 of the 4th ed. of An Essay Concerning Human Understanding (London: Awnsham & Churchill & Manship, 1690) to account for aberrant, unnatural, and habitual connections between ideas. The Rev. John Gay wrote an anonymous "Preliminary Dissertation concerning the Fundamental Principle of Virtue or Morality" which was appended to Edmund Law's translation of William King's An Essay on the Origin of Evil, 2 vols. (2nd ed., Cambridge: Thurlbourn, 1732). Gay employed the association of ideas and the pleasure-pain principle to account for the origin of the moral sense and all the passions, in lieu of considering them to be innately given instincts.   
48 David Hartley, Observations on Man, His Frame, His Duty, and His Expectations, 2 vols. (London: Leake & Frederick, 1749).   
49 For an excellent contemporary exposition of associationism, see J. S. Mill, "Bain's Psychology" (1859), reprinted in Dissertations and Discussions, Vol. III (London: Long mans, 1867), pp. 97-152.   
50 Alexander Bain, The Senses and the Intellect (London: Parker, 1855), p. v.   51 Alexander Bain Autobiography (London: Longmans, 1901), pp. 27-28, 50, 90, 112, 215, 237-238, 259-260; On the Study of Character, Including an Estimate of Phrenology (London: Parker, 1861), esp. pp. v-vi, 16. Michael St. John Packe, The Life of John Stuart Mill (London: Secker & Warburg, 1954), pp. 289, 271, 291, 359.   
52 Bain, On the Study of Character, pp. 147-150, 155-158, 177; Mill, Dissertations and Discussions, Vol. III, p. 110; Th. Ribot, English Psychology trans, J. Fitzgerald (London: King, 1873, p. 198.   
53 In 1861 Bain said, "We must not, however, stop short of the hemispheres in our explanation of the control of the voluntary muscles ...." (On the Study of Character, p. 153), but this is the only passage in his writings which expresses this view.