WILLIS'S PATH TO THE BRAIN

Willis is in many ways very apt for such purposes of exemplification. He was no great genius. Rather, he was an ordinary man in extraordinary times. He lived through a revolution and a reaction. His life straddled the transition between late-Renaissance and early-Enlightenment England, and he lived it successfully in two contrasting spheres of academic reclusion and worldly bustle.

Willis was born in 1621 near Oxford, and stayed in the shadow of its spires for almost half a century, moving to London only in 1667, where he died in 1675.^[9] In his early life he was surrounded by the traditional

[9] To date, the only full-length biography is Hansruedi Isler, Thomas Willis: Ein Wegbereiter der modernen Medizin, 1621-1675 (Stuttgart: Wissenschaftliche Verlagsgesellschaft, 1965); this was translated, with additions, by Islet, Thomas Willis, 1621-1675: Doctor and Scientist (New York: Hafner, 1968). The late Kenneth Dewhurst has been the scholar most active in writing about Willis over the past two decades. Much biographical material is contained in the long introductions to his editions of Willis manuscript material: Thomas Willis's Oxford Lectures (Oxford: Sandford, 1980), 1-49; Willis's Oxford Casebook (1650-52) (Oxford: Sandford, 1981), 1-59. A useful synoptic view of Willis's life and scientfic ideas is Robert G. Frank, Jr., "Thomas Willis," in Dictionary of Scientific Biography (New York: Charles Scribner's Sons, 1970-), 14: 404-409.

verities of crown and church; then, when King confronted Parliament, the world was, in Christopher Hill's phrase, turned upside down. Like many, he fought for the Royalist cause between 1643 and 1646, main-rained a secret opposition through the Commonwealth period, and was elated at the Restoration. Nor did Willis possess unusual qualities of personal magnetism. He was merely honest in speech and conservative in mentality. With typical earthiness, John Aubrey tells us that Willis was of "middle stature: darke red haire (like a red pig)," and "stammered much."^[10] Antony Wood called him simply "a plain man, a man of no carriage, little discourse, complaisance, or society."^[11] What was there about his life that brought him to the enterprise of grounding mental phenomena in neural tissue? His biography, which has been reasonably well explored, contains scattered bits of evidence that bear upon the origins of his neurological work.

Willis was first and last a clinician. He began practicing medicine at Oxford about age 24, and continued his profession daily until the week of his early death at age 54. The greater part of his first book in 1659 applied ideas of fermentation to explain fevers,^[12] and his last, the Pharmaceutice rationalis of 1674, was an omnium-gatherum of his clinical judgments and prescriptions.^[13] He was a successful practitioner, but this came only slowly. As a young doctor in the late 1640s he hustled for pa-

[10] "Brief Lives," Chiefly of Contemporaries, Set Down by John Aubrey, between the Years 1669 & 1696, ed. Andrew Clark (Oxford: Clarendon Press, 1898), 2: 303.

[11] Anthony Wood, Athenae Oxonienses: An Exact History of All the Writers and Bishops Who Have Had Their Education in the University of Oxford, new ed., ed. Philip Bliss (London: Rivington, 1813-1820), vol. 3, col. 1051.

[12] Thomas Willis, Diatribae duae medico-philosophicae, quarum prior agit de fermentatione sive de motu intestino particularum in quovis corpore; altera de febribus, sive de motu earundum in sanguine animalium. His ascessit dissertatio epistolica de urinis (London, 1659). The three treatises are paginated separately, so I shall refer to them as De fermentatione, De febribus, and De urinis. All were translated by Pordage as "Of fermentation," "Of feavers," and "Of urines" [separately paginated], in Willis, Practice of physick. In this, as in other works of Willis for which more than one edition was published in Willis's lifetime, one must exercise caution in using the Pordage translation; it sometimes contains intercalated sentences, paragraphs, or even sections that are not found in the first edition.

[13] Thomas Willis, Pharmaceutice rationalis. Sive diatriba de medicamentorum operationibus in humano corpore [Pars I] (Oxford, 1674); translation by Pordage as "Pharmaceutice rationalis, Part I," in Willis, Practice of physick. Thomas Willis, Pharmaceutice rationalis... Pars secunda (Oxford, 1675); translation by Pordage as "Pharmaceutice rationalis, Part II," in Willis, Practice of physick.

tients on market days in neighboring towns, and a clinical notebook kept in 1650 shows a practice that was certainly not booming.^[14] But by 1657 he had acquired enough skill, patients, and financial security to marry, and the Restoration set his career firmly on the upward path. By the early 1660s he was buying properties in Oxford, and just before his departure from there he had the highest income in the town.^[15] The move to London brought more success and, as Wood noted, "in very short time after he became so noted, and so infinitely resorted to, for his practice, that never any physician before went beyond him, or got more money yearly than he."^[16]

But Willis was successful in more than simply monetary terms. He was a remarkable clinical observer. His characterizations of epidemics were particularly acute; he reported in detail the first English outbreak of war typhus among the Oxford troops in 1643, cases of plague in 1645, measles and smallpox in 1649 and 1654, and influenza in 1657. He also recorded what seems to be the first reliable clinical description of typhoid fever. For a variety of other clinical descriptions, his works contain in each case the locus classicus: myasthenia gravis; the distinction between acute tuberculosis and the chronic fibroid type; the first clinical and pathological description of emphysema; extrasystoles of the heart; aortic stenosis; heart failure in chronic bronchitis; emboli lodged in the pulmonary artery; the first European to note the sweet taste of the urine in diabetes mellitus.^[17] Overall, he was a moderate in therapy^[18] and seems—at least as reflected by his writings—to have had no great knowledge of Galen or Hippocrates. Throughout his life, his abiding interest was his patients, not learned medicine.

In addition to being an acute but conservative physician, he was also

[14] Aubrey, "Brief Lives " 2: 303. Cf. Dewhurst, Willis's Oxford Casebook, where Willis notes seeing only forty-six separate patients in 1650; many, however, were seen more than once, and it seems most likely that Willis did not record all of his cases.

[15] On Willis's growing wealth and acquisition of properties, see Dewhurst, Willis's Oxford Lectures, 9-12, 14-18, 20-26; Willis's Oxford Casebook, 41-42, 55-56.

[16] Wood, Athenae, vol. 3, col. 1051.

[17] See, for example, the selections from Willis's writings in Ralph H. Major, Classic Descriptions of Disease (Springfield, Ill.: Charles C. Thomas, 1932), 121-124, 133-136, 192-194, 534-536, 541-545, 591-593. A good overview of Willis's clinical accomplishments is R. Hierons, "Willis's Contributions to Clinical Medicine and Neurology," Journal of the Neurological Sciences 4 (1967); 1-13.

[18] Willis's practice, as it appeared to his contemporaries, is reflected in the diary-like commonplace books of his younger Oxford contemporary, John Ward; see Robert G. Frank, Jr., "The John Ward Diaries: Mirror of Seventeenth-Century Science and Medicine," Journal of the History of Medicine and Allied Sciences 29 (1974): 147-179.

a staunch churchman. He seems originally to have been destined for holy orders, but the Civil War derailed his clerical career. He maintained his strong Anglicanism throughout the interregnum, and his residences at Oxford, both when he lived in Christ Church and in Beam Hall, were used regularly for sub-rosa worship. His friends during this period included John Fell (whose sister he married), Gilbert Sheldon, John Dolben, and Richard Allestree; after the Restoration these four became, respectively, the Bishop of Oxford, the Archbishop of Canterbury, the Archbishop of York, and the Regius Professor of Divinity as well as the Provost of Eton.^[19] Willis was especially close to Fell and Allestree; not only did Richard Allestree take a course in chemistry from Willis, but his brother James, the printer, brought out Willis's first four books.^[20]

Willis's religion, although not at all theological, was more than merely a matter of friends and politics. He gave to the poor all the fees he earned on Sundays. He went to church daily, and when he found that his London practice precluded midday worship, he paid a priest at St. Martin's in the Fields to read prayers early and late, for such as he, who could not otherwise attend. Characteristically, he endowed this position in his will. As Wood said, he "left behind him the character of an orthodox, pious, and charitable physician."^[21]

This orthodoxy squared with his early philosophical education. He had matriculated at Oxford in the boom years of the mid-1630s, proceeding to the B.A. in 1639, and to the M.A. in 1642.^[22] At that time the colleges were throwing up new buildings with abandon to accommodate the thousands who, largely for social reasons, wanted a traditional uni-

[19] Wood, Athenae, vol. 3, cols. 1049—1050; Anthony Wood, The History and Antiquities of the University of Oxford, ed. and trans. John Gutch (Oxford: For the editor, 1796), 2: 613; Cf. the brief obituary by John Fell which was appended to the Pharmaceutice rationalis... Pars secunda, sig. b3v-b4r; "Pharmaceutice rationalis, Part II," sig. A2v-A3r.

[20] Richard Allestree was reputed to be the author of The causes of the decay of Christian piety (London, 1668), and on the copy in the Bodleian Library is the anonymous note that "Dr. Allestree was author of this book, and wrote it in the very same year wherein he went thro' a course of chymistry with Dr. Willis, which is the reason why so many physical and chymical allusions are to be found in it": Dictionary of National Biography 15: 87, under entry "Pakington". Other than purely conventional figures of speech, there are medical or chemical references in Causes at pp. 4-5, 29, 58, 75, 118-119, 122, 253. James Allestry, Richard's brother, published Willis's Diatribae duae (1659), Cerebri anatome (1664), Pathologiae cerebri (1667), and Affectionum (1670).

[21] Wood, Athenae, vol. 3, col. 1053.

[22] Joseph Foster, ed., Alumni Oxonienses: The Members of the University of Oxford, 1500 -1714 (Oxford: Parker, 1891-1892), 4: 1650. Willis matriculated from Christ Church, 3 March 1636/7; B.A., 19 June 1639; M. A., 18 June 1642.

versity education.^[23] The curriculum was still highly Scholastic, and was organized around the two medieval elements of lectures and disputations.^[24] Especially in the years between the B.A. and the M.A., Willis would have studied traditional natural philosophy, geometry, and astronomy. He would have dutifully read his Aristotle, absorbing what he was later to call "those vain figments," the Peripatetic forms and qualities.^[25] Although Willis is often—and rightly—portrayed as one of the new breed of savant that the seventeenth century created, he was certainly perceived by his contemporaries as intellectually reliable enough that, in 1660, through the influence of Sheldon, he was elected Sedleian Professor at £120 per annum.^[26]

Physician, pillar of the church, Scholastic—described thus far, Willis would hardly seem an innovator. How did he come to his reputation as a master of brain anatomy and theoretician of the soul? His portal of entry, I would argue, was originally not anatomy, as one would expect, but a subject more appropriate to the humble prescribing medico: chemistry. As early as 1648, when he still lived in bachelor rooms in Christ Church, he joined with another Anglican perforce turned physi-

[23] On the growing popularity of the English universities see Mark H. Curtis, Oxford and Cambridge in Transition, 1558-1642 (Oxford: Clarendon Press, 1959); Kenneth Charlton, Education in Renaissance England (London: Routledge and Kegan Paul, 1965); Hugh Kearney, Scholars and Gentlemen: Universities and Society in Preindustrial Britain, 1500-1700 (Ithaca, N.Y.: Cornell University Press, 1970); Lawrence Stone, ed., The University in Society (Princeton: Princeton University Press, 1974). In the 1540s Oxford admitted about 40 B.A.s and 20 M.A.s each year; by the 1620s this had grown to the extent that about 400 new students came to Oxford each year, of whom an average of 240 would proceed to the B.A., and about 150 to the M.A.; see Robert G. Frank, Jr., "Science, Medicine and the Universities of Early Modern England: Background and Sources," History of Science 11 (1973): 194-216, 239-269, especially 213. For the physical growth of the colleges in the pre-Civil War period, see the Victoria History of the County of Oxford, ed. H. E. Salter and M. D. Lobel (London: Institute of Historical Research, 1954), 3:96, 102, 115-116, 127-128, 169-170, 216-217, 240-242, 272-274, 283-285, 289.

[24] The relation between statutory forms and scholastic content at an English university is brilliantly set forth in William T. Costello, The Scholastic Curriculum at Early Seventeenth-Century Cambridge (Cambridge, Mass.: Harvard University Press, 1958). On the relation of science to the scholastic format, see Frank, "Science, Medicine and the Universities," 200-207.

[25] For a description of the arts curriculum at Oxford in the late sixteenth and early seventeenth century, see Andrew Clark, Register of the University of Oxford, vol. 2 (1571-1622), part 1 (Oxford: Oxford Historical Society, 1887).

[26] The documents on Willis's election are in the Oxford University Archives, "Regis-trum Convocationis, 1659-1671," reverse codex f. 4r-v.

cian, Ralph Bathurst, in preparing chemical compounds.^[27] His case notes of 1650, although largely Galenic in framework, show him edging toward chemical explanations of blood composition. Take, for example, the phenomenon of diffused pains; Willis thought they were due to an "acrid salt."^[28] By 1652 Willis was one of an inner circle of eight Oxford virtuosi who, according to Seth Ward, had "joyned together for the furnishing an elaboratory and for makeing chymicall experiments wch we doe constantly every one of us in course undertakeing by weeks to manage the worke."^[29] Willis's neat accounts of money "laid out at Wadham coll" for chemical apparatus and supplies, written in the back of one of his surviving casebooks, no doubt dates from his rota of managing "the worke." It was no mean operation; the expenses up to that point totaled almost twenty-five pounds, at a time when a college fellow was paid three pounds a years to tutor a young gentleman in Oxford.^[30] As Willis came to know other virtuosi, such as John Wilkins and Robert Boyle, his reputation as a chemist spead.^[31] The London projector Samuel Hartlib recorded in November 1654 that

Dr. Wellis [sic] of Dr. Wilkins acquaintance a very experimenting ingenious gentleman communicating every weeke some experiment or other to Mr. Boyles chymical servant, who is a kind of cozen to him. He is a great Verulamian philosopher, from him all may bee had by meanes of Mr. Boyle.^[32]

[27] See the letters of John Lydall from Oxford in 1649 referring to "Mr. Willis our Chymist," extracted and explicated in Robert G. Frank, Jr., "John Aubrey, F.R.S., John Lydall, and Science at Commonwealth Oxford," Notes and Records of the Royal Society of London 27 (1973): 193-217, especially 196-198, 213.

[28] Dewhurst, Willis's Oxford Casebook, 109; other references of a chemical bent are on pp. 82, 83, 98, 110, and 119.

[29] Seth Ward to Sir Justinian Isham, 27 February 1652, in H. W. Robinson, "An Unpublished Letter of Dr. Seth Ward Relating to the Early Meetings of the Oxford Philosophical Society," Notes and Records of the Royal Society of London 7 (1949): 68-70.

[30] Dewhurst, Willis's Oxford Casebook, 153-154.

[31] Wilkins was installed as Warden of Wadham in April 1648 (Wood, History and Antiquities 2: 570), although given their difference in politics, they may not have gotten to know each other until their common experience in William Petty's club about 1650. Cf. Robert Boyle to Ralph Bathurst, 14 April 1656, where he sends his service "to Dr. Willis, Dr. Ward, and the rest of those excellent acquaintances of yours, that have been pleased to tolerate me in their company" (Thomas Warton, The life and literary remains of Ralph Bathurst, M.D. [London, 1761]. pp. 162-164).

[32] Samuel Hartlib, "Ephemerides" [diary-like commonplace books], 1654, ff. WW-WW 7-8, Harlib Papers, Sheffield University Library. The Hartlib Papers are quoted by the kind permission of their owner, Lord Delamere.

By June 1656 Willis had completed his first chemical work, "De fermentatione"; he circulated it among his fellow scientists in Oxford, and word of it even reached London.^[33] In late 1658 he appended to it some additional tracts on fevers and on urines, and published the whole as Diatribae duae medico-philosophicae (1659).^[34] The book attracted much attention not only in Willis's coterie but in London and abroad.^[35] To his local reputation as an adept, Willis thereby added an international one as a theoretician of the spagyric art.

Since Willis's ideas about the animal and human body were built upon his chemistry, one must understand something about it in order to see how he approached problems of brain function. All bodies, he believed, were composed of five "principles": spirit, sulphur, salt, water, and earth. The last two were traditional Aristotelian "elements," while the first three were modifications of Paracelsian "principles"—in his chemistry, as in most other things, Willis was always the compromiser between ancients and moderns.

But unlike Aristotelians and Paracelsians, Willis did not believe that the five principles were names for homogeneous substances; rather, they were labels for categories of particles. All spirit particles, for example, shared the property of being highly subtle and active. They were always

[33] Hartlib, "Ephemerides," 1656, f. 48-48-3, where Hartlib noted that Willis was "a leading and prime man in the Philosophical Club at Oxford," who "hath written a treatise De Fermentatione," which John Aubrey commended highly. Robert Wood, who was at Oxford from 1640 to 1656, and a year younger than Willis, wrote to Hartlib: "If the Booke you write of de Fermentatione be Mr Willis his of Oxford, I am confident it is an excellent peece, having formerly seen some sheets of his upon ye subject, when we met at a Club, at Oxford" (Wood to Hartlib, 9 February 1658[/9], Hartlib Papers, Bundle XXXIII (1)).

[34] Cf. A Transcript of the Registers of the Worshipful Company of Stationers, from 1640-1708 (London: Privately printed, 1913-1914), 2: 207, where the Diatribae duae was licenced on 26 November 1658.

[35] On 16 December 1658, Hartlib thanked Boyle for sending a copy of Willis's Dia-tribae duae from Oxford, and noted of the London chemist Frederick Clodius that his "chemical son's head and hands are much taken up with animadversiones on Dr. Willis's book, he having very clear reason and experiences to dislike very many particulars in it: but, no doubt, of this he will write himself" (Hartlib to Boyle, in The works of the Honourable Robert Boyle, ed. Thomas Birch, 2d ed. [London, 1772], 6: 115-116). Three months later Robert Wood wrote from Dublin: "A frend from Oxford has sent me Mr. Willis his much approved Booke de Fermentatione, so yt though I shall not now need yours... yet I shall still value your intentions as highly as I do the booke it selfe" (Wood to Hartlib, 2 March 1658[/9], Hartlib Papers, Bundle XXXIII (1)). Boyle also passed on a copy to John Beale in Herefordshire: cf. Samuel Hartlib to John Worthington, 26 June 1659, The Diary and Correspondence of Dr. John Worthington, ed. James Crossley (Manchester: Chetham Society. 1847), 1: 135.

attempting to fly out of an object, and had to be bound to other, heavier particles. But because not all spirit particles were of identical size and activity, they could not all fly away at the same time. "Spirit," for Willis, described a population of particles with common characteristics and activities, but which, like individuals that made up a species, were not necessarily identical.

The other four elements were conceived in a similar manner. Sulphureous particles were rather less active than spirit, but they too were capable of flying away. Less subtle than spirit, they were more vehement and unruly. With a little motion, they produced maturation and sweetness; with more motion, heat; with the maximum motion, the body dissolved into flames. Salt was of a more fixed nature than the previous two; it bestowed solidity on things, and retarded their dissolution. The two last principles served as passive matrices for the active ones. If particles of earth predominated, then the substance was solid; if those of water, it was liquid. Willis could, then, look at a biological substance like blood, or a part of the brain, and conceive of it as a heterogeneous population of particles, of varying types, and varying motions. Particles of different principles could combine with each to produce "copula"—spirito-sulphureous, salino-sulphureous, and so forth—which combined the chemical properties of their constituent parts.^[36]

Note, though, what Willis had done. He had created a corpuscular matter-theory, and its correlate chemistry, in a way that differed from classical atomism, which did not allow matter to have properties in and of itself. His youth, the 1630s and 1640s, had been a time of revival, and reworking, of Epicurean corpuscular theories.^[37] René Descartes had made particles of matter in motion the basis of his supremely influential Principia philosophiae (1644)^[38] Although Descartes's mechanistic explanations applied to animal bodies appeared only in his posthumous De l'homme (1664), many of his physiological ideas were expounded earlier by his Dutch disciples, Henrik de Roy (Henricus Regius) in his Fundamenta physices (1646) and Fundamenta medica (1647), and Cornelis

[36] Willis, De fermentatione, 1-17; "Of Fermentations," 1-8. The Pordage translation includes material added in later editions.

[37] On the problems and sources of early modern atomism and the corpuscular philosophy, see Kurd Lasswitz, Geschichte der Atomistik vom Mittelalter bis Newton (Hamburg: Leopold Voss, 1890); Marie Boas, "The Establishment of the Mechanical Philosophy," Osiris 10 (1952): 412-541; Robert Hugh Kargon, Atomism in England from Harlot to Newton (Oxford: Clarendon Press, 1966).

[38] René Descartes, Discours de la méthode (Leiden, 1637); Principia philosophiae (Amsterdam, 1644); De l'homme (Paris, 1664).

Hooghelande in his Cogitationes (1646).^[39] Marin Mersenne's brand of mechanism was most clearly delineated in the Cogitata physico-mathematica (1644).^[40] Pierre Gassendi's massive three-volume Animadversiones in decimum librum Diogenis Laertii (1649) established him as the leading spokesman for, and interpreter of, Epicurean atomism as applied to science.^[41] Gassendi's was the most highly ramified of the corpuscularian philosophies. According to him, there was only matter and the void. Matter was of one type, and it was only the varying size and figure of the atoms, and their concretion into second-order particles called moleculae, that constituted perceived differences in matter.^[42] In page after doublecolumned page, Gassendi went on to show how light, color, sound, odors, rarity, density, perspicuity, opacity, subtility, hardness, smoothness, fluidity, humidity, and ductility—all could be transposed out of the Aristotelian categories of essences and substantial forms, into the matter-and-motion categories of the atomistic conceptual scheme.^[43]

Willis was familiar with much of this literature, and explicitly cites Descartes, Regius, Hooghelande, Mersenne, and Gassendi. Yet he preferred a corpuscularian chemistry in which particles, although of possibly differing activities, had inherent properties by which they could act. In this version, he said, chemistry could demonstrate the principles of natural philosophy, whereas the "Epicurean hypothesis" only supposes them.^[44]

However, Willis did not come by his corpuscularianism merely in the library. It was nonexistent in his casebook of 1650, well established in the De fermentatione of 1656, and grew into efflorescence in his works written in the 1660s. Whence came such an intellectual trajectory? I

[39] Henrik de Roy, Fundamenta physices (Amsterdam, 1646) and Fundamenta medica (Utrecht, 1647); Cornelis Hooghelande, Cogitationes, quibus Dei existentia et animae spiritualitas, et possibilis cum corpore unio, demonstrantur; necnon brevis historia oeconomiae corporis animalis proponitur, atque mechanice explicatur (Amsterdam, 1646).

[40] Marin Mersenne, Cogitata physico-mathematica in quibus tam naturae quam artis effectus admirandi certissimis demonstrationibus explicantur (Paris, 1644). On Mersenne see the excellent study by Robert Lenoble, Mersenne; ou, La naissance du mécanisme (Paris: Vrin, 1943).

[41] Pierre Gassendi, Animadversiones in decimum librum Diogenis Laertii (Lyon, 1649); on Gassendi's atomism see Bernard Rochot, Les travaux de Gassendi sur Epicure et sur l'atomisme, 1619-1658 (Paris: Vrin, 1944), and Lasswitz, Geschichte der Atomistik 2: 126-188.

[42] Gassendi, Animadversiones 1: 222-236.

[43] Ibid., 236-362.

[44] Willis, De fermentatione, 4; "On fermentation," 2. The English translation includes a remark that if anyone were to say that the chemical and atomical schemes can be brought together, he would not disagree; but he will leave it to those more clever than he to devise or dream philosophy.

would argue that it was rooted in Willis's experiences in informal scientific groups that met at Oxford in the 1650s and 1660s. Among the participants in these groups were men like William Petty, Robert Boyle, and John Wallis, all of whom we know were, from their Continental contacts and reading, particularly interested in Gassendian atomism.^[45] Willis worked with men like these by being a member of no fewer than five such groups that met over the period from about 1648 to 1667.^[46] The first was a small chemistry group with Ralph Bathurst and John Lydall that worked at Trinity and Christ Church about 1648-1649.^[47] The second was organized by William Petty from late 1649 to early 1652, at his lodgings over an apothecary shop in the High Street. The third convened, from the early 1650s to about 1657, at Wadham College under the auspices of John Wilkins, its Warden. It was by far the largest and most well-organized of the groups, and provided part of the nucleus for the founding of the Royal Society in London in 1660. The fourth group met rather more sporadically at Robert Boyle's lodgings in the High Street, from late 1657 to late 1659, and from July 1664 to April 1668. And the last was Willis's own, largely of physicians and chemists, that met at Beam Hall, in Merton Street, from the late 1650s up to Willis's departure to London in 1667.^[48]

Through each of these groups in which Willis participated there were continuities and discontinuities of membership. Younger men became interested in scientific topics, and were brought into activities, while

[45] For evidence of the popularity of the French and Dutch mechanists among Oxford scientists, see Robert G. Frank, Jr., Harvey and the Oxford Physiologists: Scientific Ideas and Social Interaction (Berkeley, Los Angeles, London: University of California Press, 1980), 92-93·

[46] For a survey of Oxford scientific groups in the 1650s and 1660s, see ibid., 43-89; also Charles Webster, The Great Instauration: Science, Medicine and Reform, 1626-1660 (New York: Holmes and Meier, 1976), 153-178.

[47] Frank, "John Aubrey," 196-198.

[48] On the venues, membership, and activities of the Petty, Wilkins, and Boyle clubs, see Frank, Harvey and the Oxford Physiologists, 52-57, and the sources cited in the notes on pp. 312-314. Willis's membership in these groups is recorded in the following sources: Bodleian Library, MS. donat. Wood 1, pp. 1-3; John Wallis, A defence of the Royal Society (London, 1678), 8; John Wallis's autobiography (1697) in Peter Langtoft's chronicle, ed. Thomas Hearne (Oxford, 1725), 1: clxiii-clxiv; Wood, History and Antiquities 2: 633; Thomas Sprat, The history of the Royal-Society of London, for the improving of natural knowledge (London, 1667), 52-58; Aubrey, "Brief Lives " 2: 141; participant in the "resurrection" of Anne Green, see [Richard Watkins], Newes from the dead, 2d ed. (Oxford, 1651, 1-8; Walter Pope, The life of the fight reverend father in God Seth, Lord Bishop of Salisbury (London, 1697), 29.

others moved away from Oxford or lost interest. Most of all, these shifting constellations gave rise to numerous cooperative research projects. The ethos was one not of discussion and debate but of experimentation, trial, and manual exploration. Again and again, clusters of investigators served as helpmates, audience, and witnesses in one another's scientific work.

This then was the constellation of elements in Willis's life at the time of the Restoration, the six kinds of conceptual and social raw material out of which one shaped an approach to the relation of brain and soul. They reflected the many sides of the newly elected professor of natural philosophy: Willis the clinician of increasing acuity and fame; Willis the staunch Royalist and devout Anglican; Willis the man of traditional philosophical education, recently placed into an endowed professorship; Willis the enthusiastic experimental chemist; Willis the afficionado of corpuscular philosophies; and Willis the ever-active member of Oxford scientific circles.