0521834333 cambridge university press the cambridge companion to lockes essay concerning human understanding mar 2007

In addition to editing The Cambridge nion to Locke 1994 and a volume of writings by Hobbes andBramhall on Liberty and Necessity 1999 for the Cambridge Texts Compa-in the History of Philo

L O C K E ’ S ‘ ‘ E S S A Y C O N C E R N I N G HUMAN UNDERSTANDING’’

First published in 1689, John Locke’s Essay concerningHuman Understandingis widely recognized as among thegreatest works in the history of Western philosophy TheEssayputs forward a systematic empiricist theory of mind,detailing how all ideas and knowledge arise from senseexperience Locke was trained in mechanical philosophy,and he crafted his account to be consistent with the bestnatural science of his day The Essay was highly influential,and its rendering of empiricism would become the standardfor subsequent theorists The innovative ideas in thismonumental work continue to speak to philosophers inthe modern world

This Companion volume includes fifteen new essaysfrom leading scholars Covering the major themes ofLocke’s work, they explain his views, while situating theideas in the historical context of Locke’s day and oftenclarifying their relationship to ongoing work in philosophy.Pitched to advanced undergraduates and graduate students,

it is ideal for use in courses on early modern philosophy,British empiricism, and John Locke

Lex Newman is associate professor of philosophy at theUniversity of Utah

c o m p a n i o n s:

ABELARD Edited by jeffrey e brower and kevin

g u i l f o y

ADORNO Edited by tom huhn

AQUINAS Edited by norman kretzmann and eleonore

s t u m p

HANNAH ARENDT Edited by dana villa

ARISTOTLE Edited by jonathan barnes

AUGUSTINE Edited by eleonore stump and norman

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BACON Edited by markku peltonen

SIMONE DE BEAUVOIR Edited by claudia card

DARWIN Edited by jonathan hodge and gregory

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DESCARTES Edited by john cottingham

DUNS SCOTUS Edited by thomas williams

EARLY GREEK PHILOSOPHY Edited by a a longFEMINISM IN PHILOSOPHY Edited by miranda frickerand jennifer hornsby

FOUCAULT Edited by gary gutting

FREUD Edited by jerome neu

GADAMER Edited by robert j dostal

GALILEO Edited by peter machamer

GERMAN IDEALISM Edited by karl ameriks

GREEK AND ROMAN PHILOSOPHY Edited by david

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continued following the Index of Passages Cited

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i s b n 0 -521-83433-3 (hardback) – isbn 0-521-54225-1 (pbk.)

1 Locke, John, 1632–1704 Essay concerning human understanding.

2 Knowledge, Theory of I Newman, Lex, 1957–

II Title III Series.

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List of Contributors page ix Note on Texts and Citations xiii Introduction

10 Language, Meaning, and Mind in Locke’s

m a r g a r e t a t h e r t o n is professor of philosophy at the University

of Wisconsin, Milwaukee She is the author of Berkeley’s tion in Vision(1990) and the editor of Women Philosophers in theEarly Modern Period (1994) and The Empiricists (1999) She iscurrently working on a second book about Berkeley’s philosophy

Revolu-m a r t h a b r a n d t b o l t o n is professor of philosophy at RutgersUniversity She is the author of papers on a variety of figures andtopics in seventeenth- and eighteenth-century philosophy, includ-ing Locke’s theory of sensory perception and knowledge, hisphilosophy of language, and his views on substance and identity

v e r e c h a p p e l l is professor of philosophy at the University

of Massachusetts In addition to editing The Cambridge nion to Locke (1994) and a volume of writings by Hobbes andBramhall on Liberty and Necessity (1999) for the Cambridge Texts

Compa-in the History of Philosophy series, he is the author, with WillisDoney, of Twenty-Five Years of Descartes Scholarship (1987) andeditor of the twelve-volume Essays on Early Modern Philosophersseries (1992) He has also edited collections of recent articles onDescartes (1997) for Garland and on Locke (1998) for the OxfordReadings in Philosophy series

l i s a d o w n i n gis professor of philosophy at Ohio State University.Her publications include ‘‘The Status of Mechanism in Locke’sEssay’’ (Philosophical Review, 1998) and ‘‘Berkeley’s NaturalPhilosophy and Philosophy of Science’’ in The CambridgeCompanion to Berkeley (2005) She is currently working on abook on empiricism and Newtonianism, among other projects

m i c h a e l j a c o v i d e s is assistant professor of philosophy at PurdueUniversity He is the author of several articles on Locke, including

‘‘Locke’s Resemblance Theses’’ (The Philosophical Review, 1999)

ix

n i c h o l a s j o l l e y is chair and professor of philosophy at theUniversity of California, Irvine He is the author of Leibniz andLocke: A Study of the New Essays on Human Understanding(1984); The Light of the Soul: Theories of Ideas in Leibniz,Malebranche, and Descartes (1990); Locke: His PhilosophicalThought (1999); and Leibniz (2005).

t h o m a s m l e n n o n is professor of philosophy at the University ofWestern Ontario He is author of scores of books and articles onearly modern philosophy, including The Battle of the Gods andGiants(1993)

m i c h a e l l o s o n s k y is professor of philosophy at Colorado StateUniversity He is author of Linguistic Turns in Modern Philosophy(2005) and Enlightenment and Action from Descartes to Kant:Passionate Thought(2001) and editor of Wilhelm von Humboldt’s

On Language (1999) He is coauthor (with Heimir Geirsson) ofBeginning Metaphysics (1998) and coeditor (with Geirsson) ofReadings in Language and Mind(1996)

e d w i n mccann is professor of philosophy in the School ofPhilosophy at the University of Southern California He haspublished a number of articles on early modern philosophy,emphasizing Locke

l e x n e w m a nis associate professor of philosophy at the University

of Utah His numerous articles on Locke and Descartes haveappeared in such journals as Nouˆs, the Philosophical Review, andPhilosophy and Phenomenological Research

d a v i d o w e n is associate professor of philosophy at the University

of Arizona He has written several articles on Locke and Hume, and

he is the author of Hume’s Reason (1999)

s a m u e l c r i c k l e s s is associate professor of philosophy at theUniversity of California, San Diego He is the author of articles onLocke’s distinction between primary and secondary qualities and

on Locke’s theory of free action He is at work on Locke’s theory ofknowledge and Berkeley’s argument for idealism He also writes ontopics in ancient philosophy and is the author of Plato’s Forms inTransition: A Reading of the Parmenides (2006) In respect of hisproject for this volume, he would like to thank Michael Hardimon,

Wayne Martin, Dana Nelkin, David Owen, Don Rutherford, and EricWatkins for their constructive comments and suggestions He isparticularly indebted to Lex Newman, who helped him avoid anumber of mistakes, and from whose advice he has greatly benefited.

g a j r o g e r sis professor of the history of philosophy emeritus atKeele University and the founder-editor of the British Journal forthe History of Philosophy He is the author of Locke’s Enlight-enment (1998) and the author of more than 100 articles on thehistory of seventeenth-century philosophy He has recently editedHobbes’s Leviathan (with the late Karl Schuhmann) and is currentlyediting the drafts of Locke’s Essay and related writings for theClarendon Edition of Locke’s Works (with Paul Schuurman)

c a t h e r i n e w i l s o n is professor of philosophy at the GraduateCenter, City University of New York She works on seventeenth-and eighteenth-century philosophy and on moral theory She is theauthor, most recently, of Moral Animals: Ideals and Constraints inMoral Theory(2004) and of other books and articles on the historyand philosophy of science and the history of philosophy

g i d e o n y a f f e is associate professor of philosophy and law at theUniversity of Southern California He is the author of LibertyWorth the Name: Locke on Free Agency (2000) and ManifestActivity: Thomas Reid’s Theory of Action(2004) His articles haveappeared in such journals as the Journal of the History ofPhilosophy, the History of Philosophy Quarterly, and PhilosophicalTopics

Throughout the present volume, authors generally refer to An Essayconcerning Human Understandingas simply the Essay Quotations

of the Essay are taken from the 1975 version, edited by Peter H.Nidditch This edition is based on the original fourth edition of theEssay The text has not been modernized, thus generally preservingLocke’s original spelling, punctuation, italics, and case

Works of Locke cited using abbreviations are the following:

C The Correspondence of John Locke, ed E S de Beer 9 vols

(1976– )

CU Of the Conduct of the Understanding, ed Thomas Fowler

(1901)

D Drafts for the Essay concerning Human Understanding,

and Other Philosophical Writings, ed Peter H Nidditchand G A J Rogers 3 vols (1990– )

E An Essay concerning Human Understanding, ed Peter H

Nidditch (1975)

EL Essays on the Law of Nature, ed W von Leyden (1954)

TE Some Thoughts concerning Education, ed John W Yolton

and Jean S Yolton (1989)

W The Works of John Locke, new ed., corrected 10 vols (1823;

repr 1964)

The majority of citations refer to the Essay As per theabbreviation scheme above, these citations are marked with an E,and they specify the book, chapter, and article numbers, as well aspage numbers: for example, E II.viii.15: 137 refers to Book II,Chapter viii, article 15, on page 137 of the Nidditch edition.Citations to other works are given in parentheses, beginning with theuppercase abbreviation indicated, followed by a volume number (whererelevant) and, finally a page number preceded by a full colon Forexample, W IV: 36 refers to the Works of John Locke, volume IV, page 36

xiii

The Essay is first published in December of1689 by a year-old John Locke (1632–1704) (That same year Locke publishesthe Two Treatises of Government and the Letter Concerning Tol-eration.) The philosophical themes of the Essay are the product ofyears of thought, as many as twenty in some cases Locke continuesworking on the Essay in the decade following its initial publication

fifty-seven-He produces three updates – a second edition in 1694, a third in

1695, and a fourth in 1700 He oversees a translation into French.And he writes three public responses to objections from EdwardStillingfleet, the bishop of Worcester, one of which is a book-lengthwork in its own right The result of Locke’s efforts is an undisputedphilosophical masterpiece The systematic empiricism he developswould become the standard for subsequent theorists The impor-tance of some of the positions developed in the Essay continues tothe present day

The Essay is the product of more than simply the tireless efforts

of a gifted philosophical mind The seventeenth century is a period

of significant intellectual development in Europe – developments towhich the philosophical themes of the Essay are responsive In theopening essay of the present volume (Chapter1), ‘‘The IntellectualSetting and Aims of the Essay,’’ G A J Rogers details the historicalfactors influencing Locke

Consistent with the title of the Essay, Locke refers to ‘‘theSubject of this Treatise’’ as being ‘‘the UNDERSTANDING’’ (E:6).The Introduction states his ‘‘Purpose’’ as being ‘‘to enquire into theOriginal, Certainty, and Extent of humane Knowledge; together,with the Grounds and Degrees of Belief, Opinion, and Assent’’

1

(E I.i.2: 43) The express concern with epistemology is reflected afew lines later in Locke’s overview of his method:

First, I shall enquire into the Original of those Ideas, Notions, or whateverelse you please to call them, which a Man observes, and is conscious tohimself he has in his Mind; and the ways whereby the Understandingcomes to be furnished with them

Secondly, I shall endeavour to shew, what Knowledge the Understandinghath by those Ideas; and the Certainty, Evidence, and Extent of it.Thirdly, I shall make some Enquiry into the Nature and Grounds of Faith,

or Opinion: whereby I mean that Assent, which we give to any Proposition

as true, of whose Truth yet we have no certain Knowledge: And here

we shall have Occasion to examine the Reasons and Degrees of Assent.(E I.i.3: 44)

In the course of his inquiry, Locke explores topics that today arestudied under such headings as action theory, epistemology, ethics,metaphysics, philosophy of language, philosophy of mind, phi-losophy of science, physics, and psychology, among others

The Essay unfolds in accord with the threefold order just lined, but with a rather different emphasis than is suggested byLocke’s remarks The topics Locke lists under ‘‘First’’ occupy themajority of attention and are distributed over the first three books ofthe Essay The topics under ‘‘Secondly’’ and ‘‘Thirdly’’ are com-bined in the fourth and final book The titles of the four books are asfollows:

out-I Of Innate Notions

II Of Ideas

III Of Words

IV Of Knowledge and Opinion

Books I and II are in some sense a two-part investigation into theorigin of mental content Book I gives a negative account, addres-sing the kinds of views Locke rejects Book II gives Locke’s positiveaccount – a detailed empiricist account ‘‘Let us then suppose theMind to be, as we say, white Paper, void of all Characters, withoutany Ideas; How comes it to be furnished?’’ (E II.i.2: 104) The bulk ofLocke’s answer unfolds over the course of Book II, the longest book

of the Essay The present volume includes seven essays on topicsconnected with these first two books of the Essay

The first such essay concerns Locke’s rejection of nativism Book

I makes a series of attacks on nativism, arguing that our knowledgedoes not arise from ‘‘innate Principles,’’ or from notions ‘‘as it werestamped upon the Mind of Man’’ (E I.ii.1: 48) Unclear is whomLocke targets with these attacks, or how he understands theiraccounts In ‘‘Locke’s Polemic Against Nativism’’ (Chapter 2),Samuel C Rickless attempts to clear up the confusion, along withclarifying both the structure of Locke’s anti-innatist arguments andtheir success

Locke holds that sense experience provides the building blocks ofmental content – what he calls simple ideas From these simpleideas the mind constructs complex ideas At both levels of ideas,Locke makes further taxonomic divisions The result is an elaboratetaxonomy of ideas that helps define the organization of topics inBook II In ‘‘The Taxonomy of Ideas in Locke’s Essay’’ (Chapter3),Martha Brandt Bolton clarifies this classification scheme, whileaddressing interpretative problems associated with the majordivisions

The theory has it that simple ideas of external sense are ourwindow to the world A corpuscularian understanding of body hasimplications for how the qualities of bodies help produce such ideas

in the mind What emerges is a famous distinction between twokinds of qualities In ‘‘Locke’s Distinctions Between Primary andSecondary Qualities’’ (Chapter 4), Michael Jacovides explainsLocke’s account while arguing that it is much richer than hasbeen appreciated – Locke is in fact drawing several overlappingdistinctions

The longest chapter of the Essay concerns the idea of power.Ideas of power figure in numerous aspects of Locke’s philosophy,including the centerpiece of the chapter – his treatment of humanfreedom In ‘‘Power in Locke’s Essay’’ (Chapter 5), Vere Chappellsorts out Locke’s views on power – clarifying its widespread role inhis philosophy, and defending a compatibilist interpretation ofLocke’s views on human freedom

Appeals to substance have a distinguished philosophical history.The notion purports to get at what it is to be a thing in the mostbasic sense Recent interpretations have tended to have Locke dis-avowing the traditional notion of substance In ‘‘Locke on Sub-stance’’ (Chapter 6), Edwin McCann carefully examines four

influential such interpretations, concluding that an interpretationattributing to Locke a traditional conception of substance emerges

as superior

Related to our conceiving the world in terms of individual stances is that we have ideas of identity over time – ideas, forexample, of a mature oak tree as being the same organism as someearlier tree that looked quite different, or of our own selves as beingthe same persons that performed actions years earlier In ‘‘Locke onIdeas of Identity and Diversity’’ (Chapter7), Gideon Yaffe explainsLocke’s account, focusing especially on his famous treatment ofpersonal identity

sub-In significant respects, ideas take center stage throughout theEssay Yet Locke scholarship is divided about how he understandsthe nature of ideas – whether he regards ideas as representationalentities, and, if so, what this means At stake is whether the minddirectly perceives the world, or is instead trapped behind a veil of itsown ideas In ‘‘Locke on Ideas and Representation’’ (Chapter 8),Thomas M Lennon clarifies the contours of the debate, whilearguing that Locke does not regard ideas as imposing a barrierbetween mind and world

Book III develops further the theory of ideas, notably in tion with general ideas and essences In addition, Book III presentsLocke’s influential theory of language The present volume includestwo essays on Book III topics

connec-Experience leads us to classify objects into such kinds as trees,horses, gold, and so on We tend to assume that the world naturallydivides into such kinds – indeed, that the essences of the kinds arejust as we conceive them Locke rejects these assumptions He dis-tinguishes real and nominal essences, arguing that we classifyexternal objects based on nominal essences In ‘‘Locke on Essencesand Classification’’ (Chapter9), Margaret Atherton works throughthe texts and issues, developing an interpretation of Locke’s account.The traditional view of Locke’s philosophy of language is that itpresents a theory of linguistic meaning Recent commentators havequestioned this traditional account, arguing that it does not accu-rately portray Locke’s understanding of the signification relationbetween words and ideas In ‘‘Language, Meaning, and Mind inLocke’s Essay’’ (Chapter 10), Michael Losonsky challenges theserecent commentators and defends the traditional account

Locke’s theories of ideas and language having been expounded,Book IV turns to his theory of knowledge Locke distinguishes twomain sorts of propositional cognition: knowledge, wherein the mindhas certainty; judgment, wherein it achieves only probability Book

IV presents separate accounts of knowledge and judgment, whiletreating a number of related issues The present volume includesfive essays on Book IV topics

The opening lines of Book IV state that ‘‘Knowledge is onlyconversant’’ with ideas, because ideas are the only immediateobjects the mind ‘‘does or can contemplate’’ (E IV.i.1: 525) Thusrestricted to ideas, Locke defines knowledge as the perception of theagreement or disagreement of two ideas – a definition that hasgenerated considerable scholarly debate In ‘‘Locke on Knowledge’’(Chapter 11), I defend an interpretation of Locke’s account ofknowledge that takes his controversial definition at face value

In the course of developing the themes of Book IV, Locke makesclaims bearing on his own ontological commitments It has seemed

to many readers that his claims are inconsistent – that they revealtension in his views about the epistemic status of corpuscularian-ism, and further tension in his views about the nature of mind In

‘‘Locke’s Ontology’’ (Chapter 12), Lisa Downing examines theclaimed tensions and argues that they can be resolved

Locke maintains that inquiries into morality are those to whichour natural faculties are ‘‘most suited,’’ concluding that ‘‘Morality

is the proper Science, and Business of Mankind of general’’ (E IV.xii.11: 646) Locke’s claims about the nature of moral ideas andmoral knowledge raise many questions In ‘‘The Moral Epistemol-ogy of Locke’s Essay’’ (Chapter13), Catherine Wilson sorts throughthese various claims in an effort to clarify the account

Locke generally reserves the language of judgment for contexts ofprobability, thus distinguishing it from knowledge Since on hisview strict knowledge is quite limited in scope, it emerges thatjudgment plays an extensive role in his broader philosophical sys-tem In ‘‘Locke on Judgment’’ (Chapter14), David Owen presents ageneral interpretation of Locke’s theory of judgment, arguing,among other things, that the contributions of the intellect andthe will in Locke’s account make it importantly different fromDescartes’s well-known account

Having explained knowledge and judgment, Locke discusses twofurther grounds of assent – divine revelation, and religious enthu-siasm That these further grounds of assent are bases of religiousconviction raises questions about the balancing of faith and naturalreason In ‘‘Locke on Faith and Reason’’ (Chapter 15), NicholasJolley discusses Locke’s overall philosophy of religion, his treat-ment of faith and reason, and his treatment of enthusiasm.

Locke’s Essay covers far more topics of interest than are cussed here That his Essay presents powerful and influential phi-losophical ideas in an uncommonly systematic fashion renders it aphilosophical gold mine for both students and scholars As theessays in the present volume collectively exhibit, Locke scholarship

dis-is alive and well A host of interpretive dis-issues continue to bedebated, and much of the diversity of interpretive positions in thefield is represented in these pages That these interpretive debates

do, in many cases, track ongoing philosophical debates attests tothe ongoing relevance of Locke’s philosophy The philosophicalworld still has much to learn from the Essay

1 The Intellectual Setting

and Aims of the Essay

The Essay Concerning Human Understanding, though dated 1690,was published in late 1689, when its author was fifty-seven It hadbeen completed in Holland, where Locke had fled in 1683 It had amuch longer gestation than this suggests, however When it waspublished it was the product of a mature philosophical mind thathad been reflecting on the issues that it considers for nearly twentyyears Locke tells us in the ‘‘Epistle to the Reader’’ something of itsorigin and history He writes that five or six friends:

Meeting at my chamber, and discoursing on a subject very remote from this[i.e., human understanding], found themselves quickly at a stand, by theDifficulties that rose on every side After we had a while puzzled our selves,without coming any nearer a Resolution of those Doubts which perplexed

us, it came in to my Thoughts, that we took a wrong course; and that,before we set our selves upon Enquiries of that Nature, it was necessary toexamine our own Abilities, and see, what Objects our Understandingswere, or were not fitted to deal with This I proposed to the Company, whoall readily assented; and thereupon it was agreed, that this should be ourfirst Enquiry Some hasty and undigested Thoughts, on a Subject I hadnever before considered, which I set down against our next Meeting, gavethe first entrance into this Discourse, which having been thus by Chance,was continued by Intreaty; written by incoherent parcels, and after longintervals of neglect, resum’d again, as my Humour or Occasions permitted;and at last, in a retirement, where an Attendance on my Health gave meleisure, it was brought into that order, thou now seest it (E: 7)

We can now fill out this story in much detail, and some of thatdetail is directly relevant to understanding Locke’s purposes inwriting the book To begin with, it is known that the subject matter

of the discussion in which Locke and his friends were originally

7

engaged was ‘‘morality and revealed religion.’’1The meeting itselftook place in the winter, probably February, of 1671 and in ExeterHouse in the Strand, the London home of Lord Ashley, later firstearl of Shaftesbury, situated where the Strand Palace Hotel nowstands Whether that first document that Locke prepared for themeeting is still in existence is not certain What we have now aretwo early drafts of the Essay, both probably written in 1671 (thougheven this is not absolutely certain), known as Drafts A and B.2But

in Locke’s voluminous manuscripts there are many other references

to material relevant to the background and production of the Essaythrough its five early editions Further, in order to understandthose drafts, and therefore the published book, we have to look toLocke’s intellectual background as a philosopher, educated in thetraditions of the more puritan strands of the Church of England, and

as somebody who had entered deeply into studies in medicine,chemistry, and at least some other branches of natural philosophybefore he began to write works of philosophy as now understood.And this was against a background in which Locke had taken hisOxford first degree and was thus familiar with the main tenets ofScholastic philosophy, and in the immediately following years hadbecome familiar with and influenced by the new philosophy ema-nating from France, of which that of Descartes was by far the mostimportant

Locke had been a student and tutor at Christ Church, Oxford, thelargest and most important college in the university, from the timethat he graduated in 1656 until he moved to London to joinShaftesbury’s household eleven years later in 1667, where he was to

be based until 1675 Shaftesbury had by then become the leadingWhig politician in the country, and much of his time was spent ongovernment business During those eight years Locke often worked

as Shaftesbury’s personal assistant in dealing with matters of tics and government He was also responsible for finding Shaftes-bury’s son a wife and, in due course, for the education of the sonproduced from that marriage, the future third earl of Shaftesbury

poli-He also, as secretary of presentations, became a civil servant and

1

Locke’s friend James Tyrrell, who was one of the five or six at that meeting, wrote

as much in his copy of the Essay, now in the British Library.

2

Published as John Locke: Drafts for the Essay Concerning Human Understanding, and Other Philosophical Writings.

was responsible for dealing with ecclesiastical matters that cameunder Shaftesbury’s control as lord chancellor, the highest politicalappointment in the land When possible, Locke was also engaged inmedical practice with Thomas Sydenham, probably the greatestphysician of the age In 1668, he became a Fellow of the recentlyestablished Royal Society, attending its meetings when he was ableand renewing contacts from his days with the Oxford PhilosophicalSociety, of which the two most distinguished were Robert Boyle andRobert Hooke, but which also included many others, such asChristopher Wren, remembered as the architect of St Paul’sCathedral; the civil servant Samuel Pepys; Richard Lower, thephysician; Sir Kenelm Digby; John Wilkins, who had been one ofthe moving forces behind the new science in Oxford and who laterbecame Bishop of Chester; Nehemiah Grew, the botanist; and manyother distinguished and not-so-distinguished men of science.Perhaps enough has been said to indicate that Locke was far frombeing a standard academic philosopher in the modern sense Indeed,

as we shall see, the modern subject known as philosophy was inmany respects to be created by his Essay Although he had spentyears teaching logic, rhetoric, and moral philosophy in Oxford,Locke’s great intellectual passions in his earlier years were medi-cine and chemistry It is of major significance for understanding hisphilosophy that in these disciplines he was actively engaged inresearch with the two outstanding figures in the respective fields,Thomas Sydenham and Robert Boyle

The Royal Society was an institution that claimed to be puttinginto practice the plans for the increase in knowledge of the naturalworld that had been advocated by Francis Bacon at the beginning ofthe century Supporters of the Baconian vision had been active inboth Oxford and London during the period of the Commonwealthfollowing the English Civil War and the execution of King Charles

I in 1649, the year Locke had entered Christ Church At the heart ofBacon’s programme was the aspiration to increase people’s knowl-edge of the natural world and to use that knowledge for practicalbenefit Leading proponents of that movement in Oxford includedRobert Boyle, an aristocrat of independent means, and JohnWilkins, master of Wadham College and married to the sister of theman who was effectively the country’s ruler, Oliver Cromwell.Locke attended the chemistry classes that Boyle introduced in

Oxford and began research on respiration and on human blood withBoyle In 1660, at the Restoration of the monarchy, many of theOxford group moved back to London, and it was this group, togetherwith physicians and other men interested in natural philosophy,who were responsible for creating the new society With royalpatronage, it immediately achieved a status that would otherwisenot have been available to it and soon provided a forum for theinternational exchange of information about a wide range of naturalphenomena based on observation and experiment, in the way Baconhad advocated Locke began to attend its weekly meetings in 1668,

on his election to the Society, along with his medical work withThomas Sydenham and his many commitments to Shaftesbury

We shall look more closely at the connections between Locke andthe Baconian movement associated with the Royal Society later Butlet us now return to Locke and his studies in Oxford prior to hisarrival in London These fall into two very clear sections As anundergraduate, Locke had to follow the reading prescribed for him byhis tutor, but beginning in 1656 he could and did read much morewidely and combined his reading with practical enquiries, especially

in chemistry and medicine The undergraduate course required him

to advance further his mastery of Latin, mainly through rigorous andfrequent exercises; logic, which was, of course, that of Aristotle’ssyllogistic; mathematics and astronomy, including Euclid and con-temporary works of astronomy based on the heliocentric theory; andthe classical texts of Greece and Rome.3

It is particularly interesting that in all such enquiries, there islittle or no evidence that Locke would have encountered majorworks of what today would have been called the classics in phi-losophy No doubt he would have been familiar with the majorworks of Aristotle, but perhaps not with those of Plato Certainly hewould not have encountered as a matter of course any of the majorphilosophers of the Middle Ages Of Latin authors, only Cicero andSeneca would have been certainties And by Locke’s day none of theworks of early modern philosophers such as Bacon, Descartes,Hobbes, and Gassendi would have been included as texts

3

For more on the courses at Oxford in Locke’s day, see Feingold 1997: ‘‘The Humanities’’ and ‘‘The Mathematical Sciences and the New Philosophies.’’ On Christ Church in particular, see Bill 1988.

This does not mean, however, that they would necessarily havebeen totally excluded from any teaching In Christ Church, as inother Oxford and Cambridge colleges, each tutor had a fair amount

of flexibility in what he encouraged his pupils to read In 1667, forexample, in Jesus College, Cambridge, John North as an under-graduate read Descartes’s natural philosophy, presumably thePrincipia Philosophia, ‘‘three times,’’ and he tells us that Descarteswas studied quite widely, especially by ‘‘the brisk part of the uni-versity’’ (North 1959: 257–8)

When Locke began his studies, then, the intellectual forcesgathering in the wider world, may be identified as, first, thoseassociated with the advocacy and practice of the method of enquiryput forward by Francis Bacon in his Great Instauration, and morespecifically in his Advancement of Learning (1605) and NovumOrganum (1620), which lay at the base of the new enquiries sup-ported by those who were to form the Royal Society Second, therewas the effect of the writings of Descartes, which almost from theirinception had begun to make a significant impact on Englishthinking This was not least because several of the leading philo-sophers in England had fled to France during the English CivilWar and there had had direct contact with Descartes and otherFrench thinkers such as Gassendi, Arnaud, and Mersenne Ofthese, intellectually the most important was Thomas Hobbes, butHobbes’s immediate influence, though greater than often supposed,was somewhat diminished by the hostility with which he wasgenerally regarded in his own country Furthermore, his own per-sonal rivalry with Descartes – each saw the other as a threat to hisown standing as the leading philosopher of their generation –guaranteed that Hobbes was never to be a proponent of Cartesianphilosophy Others, such as Sir Kenelm Digby, Walter Charleton,and John Evelyn, all encouraged the study of Descartes But thethinkers who probably did most to propel him in England wereHenry More and others collectively, but perhaps not quite accu-rately, known as the Cambridge Platonists This group of thinkers,perhaps surprisingly, were themselves to have something of animpact on Locke, a point to which we shall return

The third great contemporary force acting on Locke’s thinkingwas, of course, the traditional teachings and syllabus of the uni-versities These were still dominated by the works of Aristotle, for

whom Locke was always to retain a high regard It was hiscommentators and paraphrasers whom Locke came rapidly to hold

in contempt In England, Aristotle’s teachings were given a nificant Protestant twist in order to bring them in line with thetheology of the Church of England, represented in Oxford by theteachings of two deans of Christ Church in Locke’s time, the pur-itan John Owen, appointed by Oliver Cromwell, and John Fell,made dean at the restoration of the monarchy in 1660 Both of thesemen were well disposed toward Locke during his years at ChristChurch, and Locke was careful not to court religious controversyuntil late in his life, which was in keeping with his generallycautious approach to all controversial issues

sig-Locke and his friends tell us that he did not much enjoy theundergraduate course at Oxford He objected to the scholasticsyllabus and the exercises in logic and Latin poetry But his note-books reveal that as soon as he graduated, if not before, he wasturning to wider horizons He told Damaris Masham that the firstbooks ‘‘which gave him a relish of Philosophical Studys were those

of Descartes,’’4 a claim that he confirmed himself in his Letter tothe Bishop of Worcester, in which Locke writes, ‘‘I must alwaysacknowledge to that justly-admired gentleman [Descartes] the greatobligation of my first deliverance from the unintelligible way oftalking of the philosophy in use in the schools.’’ But he goes on tosay that none of the mistakes to be found in the Essay can beattributed to Descartes, for its contents are ‘‘spun barely out of myown thoughts, reflecting as well as I could on my own mind, andthe ideas I had there’’ (W IV: 48–9)

Precisely when Locke first read Descartes is not easily mined The earliest notes that I have discovered are in Locke’sMedical Commonplace Book, which is dated 25 February 1659(1660 new style), and the latest publishing date for any book cited

deter-is 1660 The edition of Descartes that Locke used, according tohis own reference, was the Opera philosophica, third edition, pub-lished in Amsterdam in 1656.5 He enters short passages from the

4

Lady Masham in a letter to Le Clerc (January 12, 1705, p 7), a copy of which was given to me by Esmond de Beer, from a copy given him by Rosalie Colie taken from the original in the Remonstrants Library, Amsterdam.

5

In Harrison and Laslett 1971 the date of Locke’s copy is incorrectly given as 1658.

Meditationes, Principia philosophiae, Dioptrice, and Meteora, withmost of the passages coming from the Principia.

It is plausible to put a construction on this last fact about Locke’sinterest in and debts to Descartes What he found in Descartes’sphilosophy was a comprehensive and alternative account of thenature of the universe – alternative, that is, to that offered bythe standard Aristotelian explanations It was this wider vision thatgrabbed Locke’s attention, not the particular epistemological con-cerns that occupy the early sections of the Meditations There is noreason to see Locke at this early stage as being deeply engaged withany kind of epistemological enquiry, nor to see Descartes as holdingany special interest for him in this direction It is important toremember that when Locke was beginning his studies, the word

‘philosophy’ covered the whole of what we would today callnatural science as well as epistemology, moral theory, and politicalphilosophy This wider understanding of the term is what Lockewas suggesting when he claimed that Descartes had inspired hisinterest in ‘philosophy’ Too often, on coming to learn of Locke’sacknowledgment of his debt to Descartes, and influenced by a muchnarrower picture of philosophy (fostered in part by Locke’s ownwork), commentators have come to assume that the issues thatgrabbed Locke’s attention in the Meditations were the early con-cerns with scepticism But there is no reason at all to believe this to

be true Indeed, there is no reason to believe that scepticism was anissue that greatly troubled Locke at all What he found in thePrincipia was a powerful but conjectural account of the world,preceded by some methodological moves that he was later to findwanting in various ways but that did not, at this stage, engage him

in any deep reflections Those reflections were to come many yearslater Nor is there any reason to suppose that Locke in any sensebecame a Cartesian as a result of those early readings Certainly hewas to be strongly influenced by Descartes in some particularscentral to his philosophy But he never showed any commitment toDescartes’s method of enquiry and indeed had soon firmly rejected

it, as we shall see Nor is there any reason to believe that Lockefollowed Descartes in accepting an entirely mechanical account ofcausation in the physical world Indeed, it would be very difficult todemonstrate that he held to any of the beliefs that were to becomethe dogmas of modern philosophy, whether speculative or natural,

though no doubt some of the beliefs that are central to Locke’sempirical epistemology were taking at least an informal place in hisunderstanding of the world.

It is important for an appreciation of Locke’s argument in theEssay to consider in more detail some of the many similarities

as well as the differences between Locke and Descartes in theirphilosophical positions, differences that it is not always helpful tocharacterise as those between a Rationalist and an Empiricist phi-losopher One relates to their objectives in writing a work of phi-losophy Descartes tells us that what he was attempting to producewas a philosophy founded on the granite foundation of certainty.From impeccable premises the argument would proceed withineluctable force to conclusions that could not be challenged IfDescartes in the end was not so confident that he had achieved hisgoal (as the closing sections of the Principles of Philosophy seem tosuggest) or that it extended to the whole of the Principia, where thetwo later books may be read as invoking probabilist hypotheses,there can be little doubt about the original motivation

The enemy was, then, the sceptic whose defeat was central to theproject Locke began with a quite different purpose For the whole ofhis life he was quite sure that for large sections of human enquirythe outcomes could never be anything other than provisional Thestate of ‘mediocrity’ – a word Locke often uses – in which we findourselves was for him central to the human condition, and with itcame a very clear view about the fallibility of the human intellect.Certainty was possible, but only in rather small quantities and invery particular areas of enquiry To expect philosophy or any otherenquiry to produce absolute certainty in large areas of humanconcern was whistling in the wind

He was therefore interested in arguing from known self-evidentprinciples to conclusions known equally to be certainly true in onlythree areas: mathematics, morals, and some few but importantaspects of religion Although Locke accepted the certainty of theexistence of the self (Descartes’s cogito), it was not for him, as itwas for Descartes, taken as a foundational truth Nor did he everaccept the very sharp dualism between mind and body that Des-cartes inferred from his first premise Equally, Descartes’s claim, inthe way we have it in the Meditations, to have identified byintrospection the essence of mind as thought and that of body as

extension, he totally rejected Locke accepted no such purelyintellectual route to knowledge of the essence of substances Inshort, Locke rejected completely the Cartesian route to knowledge

of the essence of self and matter

However, there were many areas where he was far from hostile toDescartes’s method and innovations How many of these he took overfrom his first readings we cannot with certainty say, but they weresoon to appear in his philosophical writings and later to be incorpo-rated into his mature work By far the most important of these is thatLocke adopted the Cartesian language of ideas to characterise ourexperience That Descartes was the source for this aspect of Locke’sthought is difficult to doubt It was Descartes who first gave ‘‘ideas’’ acentral place in his account of knowledge, whereas others who werestrong influences on Locke did not Thus Francis Bacon scarcely usesthe term, and Boyle similarly eschews it Hobbes, too, though not anovert influence, but perhaps more influential than Locke cared toadmit, made no epistemically central use of the term

Nor did it feature in the ‘‘language of the schools,’’ the currentdiscussions in the lecture theatres throughout the universities ofChristendom that were equally despised by Bacon, Descartes, andLocke The term was, however, to feature centrally in the writings

of philosophers influenced by Descartes throughout the second half

of the seventeenth century Perhaps the most important of these forLocke was the Logic or the Art of Thinking (1662) by AntoineArnaud and Pierre Nicole, but it is unlikely that this could haveinfluenced Locke in these very early years, as he probably did not atthis stage read French His own copies of the Logic were the 1674edition, which he acquired during his prolonged stay in Francebetween 1675 and 1679

Locke’s rejection of syllogistic logic was clearly something that

he shared with Descartes, but it would be rash to assume that it wasDescartes who persuaded him of its redundancy But he clearlycame to agree with Descartes that intuition lies at the heart ofknowledge And perhaps even more importantly, he came to acceptthat clear and distinct ideas provide our best criterion of truth.Conversely, it was, again with Descartes, the indeterminate nature

of many ideas that lead to confusion and mistakes in our reasoning.There is no reason to doubt that Locke took many of theseCartesian thoughts away with him from his first reading of

Descartes’s philosophy No doubt he also took with him a respectfor the power of mechanical explanation to account for change inthe physical world Descartes gave mechanical interaction thecentral place in his explanation of physical phenomena, from light

to gravity and the circulation of the planets But while for Descartessuch interaction was the necessary consequence of his definition ofmatter, Locke was flexible enough to change his mind about

‘‘impulse,’’ for example, in light of what he took to be the empiricalevidence supplied by Newton’s Principia Thus in the first threeeditions of the Essay he had written that bodies operate ‘‘byimpulse, and nothing else’’ (E II.viii.11: 135); this was changed inthe fourth edition to ‘‘Bodies produce Ideas in us manifestly byimpulse, the only way in which we can conceive Bodies operate in.’’Locke’s change of wording is explained later in his Second Reply tothe Bishop of Worcester, where he writes:

You ask, ‘‘how can my way of liberty agree with the idea that bodies canoperate only by motion and impulse?’’ Answ By the omnipotency of God,who can make all things agree, that involve not a contradiction It is true, Isay, ‘‘that bodies operate by impulse and nothing else’’ And so I thoughtwhen I writ it, and can yet conceive no other way of their operation But I

am since convinced by the judicious Mr Newton’s incomparable book, that

it is too bold a presumption to limit God’s power, in this point, by mynarrow conceptions The gravitation of matter towards matter, by waysinconceivable to me, is not only a demonstration that God can, if hepleases, put into bodies powers and ways of operation above what can bederived from our idea of body, or can be explained by what we know ofmatter, but also an unquestionable and every where visible instance that hehas done so And therefore in the next edition of my book I shall take care

to have that passage rectified (W IV: 467–8)

There were other reasons that might have led Locke in his mative years to doubt that mechanism was the only causal factor inbodies To appreciate those other possibilities, we need to remem-ber that Locke was also on the way to becoming a chemist, as weshall see, and that chemistry in the early seventeenth century wasnot mechanical One way into Locke’s thoughts on such matters is

for-to return for-to that early notebook

This early notebook, as its attributed name implies, and likeseveral other of his contemporary manuscripts, contains manynotes that reflect Locke’s reading in medical matters It includes,

for example, many notes from his medical friend and teacherRichard Lower, who had, like Locke, been educated at Westminsterand Christ Church and who was destined to become, according toAnthony Wood, ‘‘the most noted physician in Westminster andLondon’’ (Wood 1813: IV: 98) Certainly his research in physiologygives him a high place in its history Another senior member

of Christ Church was Thomas Willis, whose work in medicinegenerally and on the brain in particular was of a ground-breakingorder Locke made many notes from his lectures and publi-cations Medicine, as practised in the later seventeenth century,was closely related to chemistry, specifically to iatrochemistry.The medieval domination of Galenic medicine was challenged inthe early seventeenth century by the theories of Paracelsus, whosepractical remedies based on a completely new theory of diseasewere playing a growing role in medical practice Added to this wasthe new impetus to research in medicine created by Harvey’s dis-covery of the circulation of the blood The new role that Harveygave to the heart – that of a pump – and the destruction thereby ofthe whole tradition of medicine as taught and practised in themedical schools of Europe invited a large number of research pro-jects to make sense of this new physiology and to understand itsimplications for disease Although the heart as a pump broughtmechanism into biology in a large way, there remained a multitude

of questions for which mechanical answers seemed less obvious.One of these was the place of respiration in the life cycle Why

do we breath? Why do we need to take air into our lungs so ularly? What happens to it when it encounters the blood vessels?These were difficult questions and ones for which there were noobvious answers A whole research programme beckoned It wasone in which Locke was to become much engrossed and to play asignificant role

reg-For Locke, and for Oxford science in particular, perhaps the singlemost important event at this time was the arrival in Oxford ofRobert Boyle in 1656 He was to remain there until 1668, when hemoved back to London, the year following Locke’s own move to thecapital Boyle’s role in Oxford for those years was of the greatestimportance both for science and medicine and for Locke personally

In 1659, Boyle brought to Oxford a German chemist named PeterSthael This was just at the point when Locke’s interest in medicine

and chemistry was emerging strongly in his reading and, perhapsmost importantly, in his observations and experiments Lockejoined Sthael’s class in Boyle’s house in the High Street, where,according to Anthony Wood (no friend of Locke), he was ‘‘prateingand troublesome.’’ How accurate Wood’s comment was we shallprobably never know But we might speculate that Locke was likely

to ask questions and to challenge those claims of Sthael that Lockebelieved were not supported by the evidence offered When weknow that Sthael was a Paracelsian, with a commitment toaccounts of chemical change that were highly theoretical, it would

be no surprise to find that Locke sought justifications for claims forwhich he could see no reason This may be challenged on thegrounds that it presupposes that the Locke of 1659 held the sameviews about unsupported claims that find powerful justification inthe Essay But it is likely that by this time Locke was firmlycommitted to the position that belief should be carefully propor-tioned to the evidence It is not too speculative to wonder if hesometimes found that the claims of Sthael exceeded the evidenceoffered

Locke’s relationship to Boyle involved much more than dance at Sthael’s chemistry classes From his graduating B.A in

atten-1656 to his departure for London in 1667, a very high proportion ofLocke’s time was spent in one way or another on medicine andmedical and iatrochemical research Much of this was in the com-pany of Lower, but from about 1660 onward Locke was heavilyengaged not only with Lower but also with Robert Boyle Hisnotebooks show him engaged in fundamental research about theinteraction between air, still imperfectly understood but no longerregarded as the simple element of Aristotelian and Galenic theory,and human blood in respiration The great question was the nature

of the physiological changes that occur in the lungs when webreathe, and this became the centre of their research Locke’snotebooks reveal him to have been a careful investigator at thefrontier of contemporary medical science, engaged in carefulexperiment and observation to test hypotheses about the nature ofthe changes in the blood that are brought about by the act ofbreathing His research reached a level of sophistication that ledhim close to very important discoveries, but he never quite madethe breakthrough that would have given him a central place in the

history of physiology.6The results of the work of Boyle and Lockewere not to be published for another twenty years They appeared in

1684 as Memoirs for the Natural History of Humane Blood, cially the Spirit of that Liquor by the Honourable Robert Boyle Itwas dedicated to the ‘‘very Ingenious and Learned Doctor J[ohn]L[ocke].’’ In the letter of dedication, Boyle described their worktogether, claiming that whilst observations of blood had often beenmade before, proper controlled experimentation on blood had neverbefore been carried out The work was, therefore, innovative andimportant

Espe-Locke owned more of Boyle’s books than he did those of anyother author (though few authors had written nearly as many) Hisfinal library contained about sixty separate Boyle titles, some ofthem, theological works (but, curiously, not the Natural History ofHumane Blood) There can be no doubt that Boyle’s influence onLocke’s thinking was considerable But we must also rememberthat before they came into contact Locke had absorbed the spirit ofexperimental enquiry from other leading players in the new medicalresearch, including his mentor, Richard Lower, and his colleagueDavid Thomas

This spirit was essentially the same as that whose greatspokesman was Francis Bacon, the intellectual forerunner of theRoyal Society and the man whom all of the followers, not leastBoyle himself, constantly invoked as the inspiration for the newmethod being used for the understanding of nature to which they as

a group subscribed Central to this was the belief that carefulobservation and experiment were much more important than the-ory to a correct account of the natural world Of course, there was aplace for hypotheses, but any such hypotheses must be rigorouslytested against the world When the Royal Society was formed in

1662, it took as its motto ‘Nullius in Verba’ – nothing in words In

so doing it committed itself to the notion that knowledge of thenatural world was to be obtained not by verbal exchanges but bycareful empirical enquiry The title of Boyle’s work immediatelylinks it to the Baconian programme Natural histories were under-stood to be records of careful observation and experiment uncon-taminated by conjectured explanations of the supposed phenomena

6

On Locke’s place in medicine at this time, see Frank 1980, especially Chapter 7.

or hypotheses about their causes Thomas Sprat, the first historian

of the Royal Society, set out their objectives like this:

[T]heir purpose is, in short, to make faithful Records, of all the works ofNature, or Art, which can come within their reach: that so the present Age,and posterity, may be able to put a mark on the errors, which have beenstrengthened by long prescription: to restore the Truths, that have lainneglected: to push on those, which are already known, to more varioususes: and to make the way passable, to what remains unrevel’d This is theencompass of their Design And to accomplish this, they have indeaver’d toseparate the knowledge of Nature, from the colours of Rhetorick, thedevices of Fancy, or the delightful deceit of Fables (Sprat 1959: 61–2)

The goal was the production of knowledge that could be put touseful work in improving the lot of humankind What betterexample of this was there than medical research of the kind thatLocke conducted with Boyle?

But Boyle influenced Locke in other ways, too The most famousway was with regard to the nature and properties of matter It isoften said, for example, and with reason, that Locke’s famousaccount of the distinction between the primary qualities of bodies,such as size, location, and solidity, and the secondary qualities ofcolour, sound, taste, and smell was taken over from Boyle’s account

of matter In his Origine of Formes and Qualities (1666), Boyle gave

an account of the properties of bodies that was, at least ficially, very similar to that which appears in Chapter viii of Book II

super-of Locke’s Essay Furthermore, Boyle was committed to a puscular’’ account of matter and its properties and to a mechanicalaccount of change in the physical world Indeed, what Boyle stoodfor in the background to Locke’s intellectual development was thecorpuscular or ‘‘mechanical’’ philosophy (Boyle uses the two terms

‘‘cor-as virtual synonyms)7 worked out in its most thorough way ButBoyle’s mechanical philosophy was not the materialism of Hobbes,for the former was quite sure that it ranged over only part of God’screation

Further, and this is of great importance in understanding hisrelationship to Locke, any account of the properties of matter thatthe corpuscular philosophy was able to offer could be understood

7

On this, see Anstey 2000: 2 and passim.

only as a tentative explanation of the phenomena, constantly open

to revision in light of further experimental or observational dence This, combined with his eclecticism, resulted in a lack ofsystematic explanation in his natural philosophy, even though theoverwhelming theme is the power and persuasiveness of the cor-puscular hypothesis This in its turn depended on a thoroughaccount of the qualities of bodies, and it is on these that much of hisexperimental research focussed What Boyle was to do was to offer anew kind of explanation of the properties or qualities of bodies Inthis he was not original Like many other seventeenth-centuryphilosophers, including Galileo, Descartes, Gassendi, and WalterCharleton, he followed the ancient Greek atomists, Democritusand Epicurus, in offering an atomistic account of matter and itsproperties that distinguished sharply between what, under theinfluence of Locke, came to be called the primary and secondaryqualities of bodies In fact, Boyle seems to have invented the term

evi-‘primary’ in this context, but it was Locke who seems to have beenthe first to use the term ‘secondary’ The distinction is drawnclearly by Boyle in Forms and Qualities After distinguishingbetween ‘‘the two grand and most catholic principles of bodies,matter and motion’’ (Boyle 1979: 20), he continued by saying thatmatter must be divided into parts, each of which must have theattributes of size and shape, attributes that must apply to theminutest fragments of matters as much as to anything larger Somatter must always have size, shape, and either motion or rest.These, Boyle said, may be called the ‘‘moods or primary affections

of bodies to distinguish them from those less simple qualities (ascolours, tastes, and odours) that belong to bodies on their account’’(1979: 21) It was thus that Boyle drew the famous primary/sec-ondary quality distinction, which has challenged epistemologists,especially in its Lockean form, since Locke’s day But it is impor-tant to remember that in its original form it was offered by Boyle aspart of a hypothesis (never more) about the nature of matter And it

is important to remember, when considering Locke’s account of thedistinction, that he treats the issue as an excursion into the physicalsciences from his main enterprise in the Essay After the discussion

of primary and secondary qualities, he writes: ‘‘I have in what justgoes before, been engaged in Physical Enquires a little farther than,perhaps, I intended.’’ And as an excuse and explanation, he adds: ‘‘it

being necessary to make the Nature of Sensation a little understood,and to make the difference between the Qualities in Bodies, and theIdeas produced by them in the Mind, to be distinctly conceived,without which it were impossible to discourse intelligibly of them; Ihope, I shall be pardoned this little Excursion into Natural Philoso-phy’’ (E II.viii.22: 140).

There can be little doubt of Locke’s debts to Boyle on this tinction, but it is also important to notice that Locke is quite clearlyaware of the line between natural philosophy and the nature of hisown, quite different, enquiry, and we shall return to this later Let

dis-us jdis-ust note one further aspect of Locke’s debt to Boyle It is arecurring issue amongst Locke commentators what place exactlythe mechanical hypothesis and its linked corpuscular theory play inLocke’s epistemology But it is important to realize that Locke isusually careful to distinguish between the corpuscular theory,which he treats as an hypothesis, albeit the hypothesis most likely

to be true, and his commitment to many other propositions that arenot in the same sense regarded by him as conjectural To argue, asmany have, that Locke’s epistemology presupposes the truth ofmechanism is entirely to misconstrue the relationship between hisphilosophy as we have it in the Essay and his wider beliefs about thenatural world, which he sees as conjectures open to revision in thelight of further evidence As he put it in Some Thoughts ConcerningEducation, with regard to natural philosophy: ‘‘though the world befull of Systems yet I cannot say, I know any one which can betaught a Young Man as a Science, wherein he may be sure to findTruth and Certainty Only this may be said, that the ModernCorpuscularians talk, in most Things, more intelligibly than thePeripateticks, who possessed the Schools immediately beforethem’’ (TE: 247–8)

A characteristic of Boyle’s whole approach to natural philosophy

is neatly captured by the title of a book about him, The DiffidentNaturalist (Sargent 1995) Boyle was always careful to claim nomore than he believed could be well supported by the empiricalevidence He was strongly conscious of the danger of claiming morecertainty for his views than the evidence justified Thus herefrained from following Descartes in supposing there to be vorticesthat carried round the planets and other heavenly bodies Nor would

he certainly decide whether the air pump that he used with Hooke

to carry out many of his experiments generated a true vacuum orsomething less Whether Locke learnt his own diffidence fromBoyle or not, he certainly shared with him a reluctance to claimfirm conclusions for positions that he was nevertheless inclined tobelieve were true And such, as we have seen, was his position withregard to the corpuscular hypothesis itself.

In 1663, Locke was elected Senior Censor at Christ Church, aposition that he held for twelve months and that required him togive a set of lectures These have come down to us as Locke’s Essays

on the Law of Nature They are important not only for an standing of Locke’s moral and political philosophy, but also forunderstanding his epistemology, for they contain in outline some ofthe main claims to be made later in both Drafts and in the pub-lished Essay

under-Undoubtedly the most important of these is his early ment to the empirical principle in epistemology Indeed, we can gofurther and say that it was whilst writing the lectures that Lockecame to accept it Indeed, it is in many ways right to concur withthe judgment of W von Leyden that ‘‘it seems we are justified inregarding the [lectures] as being in some sense the earliest draft ofthe Essay’’ (EL Intro: 62) For in them we find argument and com-mitment to many of the claims of the final work and even passagesthat are carried over almost verbatim into the two early Drafts andfrom there into the published Essay The Drafts have a considerablywider scope than the Essays, where he is concerned with the spe-cific subject of the law of nature – contending, for example, that it isnot known innately But the epistemological implications areidentical, even down to Locke’s claims about the scope of knowl-edge being confined to the range of simple ideas that we haveexperienced The two great faculties of knowledge, Locke claims,are reason and sense experience, but they have to work in tandem toproduce knowledge:

commit- commit- commit- sensation furnishing reason with the ideas of particular sense-objectsand supplying the subject-matter of discourse, reason on the other handguiding the faculty of sense, and arranging together the images of thingsderived from sense-perception, thence forming others and composing newones but if you take away one of the two, the other is certainly of noavail, for without reason, though actuated by our senses we scarcely rise to

the standard of nature found in brute beasts without the help of thesenses, reason can achieve nothing more than a labourer working in dark-ness behind shuttered windows The foundations on which rests thewhole of that knowledge that reason builds up are the objects of sense-experience (EL: 148–49)

For Locke, this includes our knowledge of a lawmaker, that is God,and our knowledge of that law God is known to exist because weknow through experience that the physical world exists and exhi-bits an order that could not occur by chance, and therefore theremust exist a superior and much wiser power who has a just andinevitable power over us It is equally obvious, Locke says, that Godrequires us to behave in certain ways that we can discover byconsidering our natures and the world in which we are situated

It was already armed with these beliefs that Locke entered themeeting with his friends in London in 1671 that led to the earlydrafts of the Essay He was already a committed empiricist, deeplyknowledgeable about contemporary medical research, familiar withthe writings of the leading intellectual figures of the century (ofwhom Descartes and Boyle were probably the most important), aFellow of the Royal Society, and, as advisor to Shaftesbury, wellacquainted with the political scene in England Nevertheless, inthat year he drafts the early versions of what was to become theEssay Concerning Human Understanding The word become isused advisedly, because there is a great difference between thenature of the two drafts that bears comment Draft A is written in alarge folio notebook in which Locke also made many other entries

It is written for Locke’s own personal use, though conceivably hecould have read from it to a group of friends Nor does the draftcontain any indication that it is in any sense that of somethingwhich might at that stage be thought of as a book It is also veryheavily corrected It is the working copy of something that might bethe basis for something more substantial, but only at a very earlystage It was Locke’s own first thoughts, or so it would appear Butrunning to about thirty thousand words, set out in forty-five num-bered sections, it appears to be much longer than would be appro-priate for its supposed intended purpose, an introductory paper onits subject to be read to friends This raises the question whether itmight itself be an expanded version of that first paper, one that

Locke had prepared for his own private use Draft B, on the otherhand, at 65,000 words and 162 numbered paragraphs, is about twicethe length of Draft A, and much more like a finished work – more,

in fact, like a draft book, and Locke uses the prefatory word ‘Essay’for the first time in its title From about this time Locke appears tohave carried with him a folio notebook, ‘De Intellectu’, in which hebegan to draft a version of the Essay, obviously with the object of abook in mind Unfortunately, that notebook appears not to havesurvived

The final version of the Essay is, at about 290,000 words, almostfive times the length of Draft B Despite this it covers much of thesame territory, but without nearly so much detail in its argument,presenting a thoroughly empiricist account of knowledge and itslimits Some of the topics that have since Locke’s day received themost attention from commentators are, however, entirely or almostentirely missing from Draft B Thus there is no considered treat-ment of the primary/secondary quality distinction, or of personalidentity, or of the association of ideas Indeed, these last two arecovered only in chapters added to later editions of the Essay Nordoes Draft B give the attention to the whole subject of knowledgethat we find in the final version as Book IV As Book IV is that towhich the prior three books are directed as an argument, it suggeststhat in 1671 Locke was, perhaps, not as clear as he was to becomeabout the full implications of his empiricist premises for the natureand scope of knowledge that emerge in the published work How-ever, we can be fairly confident that the reason that Locke neverproduced a text for publication in the 1670s is not that he facedoverwhelming intellectual difficulties with the topic but that, as hetells us, he had other commitments that took him away from sus-tained philosophical reflection Soon Ashley was made an earl andwas thereby destined for positions of power that required Locke to

be active on his behalf Philosophy had to be put aside

When Shaftesbury was made lord chancellor in November 1672,Locke became first secretary of presentations and then, whenShaftesbury fell from power, secretary to the Council of Trade andPlantations Later he went to France, perhaps as an agent forShaftesbury; he was to stay there for four years, much of his timespent in Montpelier at the medical school there But by early 1679 hewas back in England, probably recalled by Shaftesbury, who had once

again obtained high office and was in need of his services Fromthen until Shaftesbury’s death in Holland in 1683, Locke was muchengaged with work for him.

Earlier, whilst in France, Locke kept an annual journal that hecontinued to the end of his life In it he entered a variety of infor-mation, but the journals show that he was still very much thinkingabout matters epistemological, for there are many entries on topicsthat were later to find a place in the Essay And the entries alsoshow that Locke still had an intention of presenting his ideas in theform of a book These notes cover many of the central themes ofthat work, including, for example, knowledge, extension, species,and time Some of them reinforce passages in the Drafts, and othersshow that Locke is extending his enquiries – he quotes from theCambridge Platonists, Ralph Cudworth, and John Smith, forexample – as well as showing that he has returned to thinkingabout central and contentious issues in the philosophy of Descartes.Locke’s interest in the Cambridge Platonists was undoubtedlystimulated by a new friendship he made in 1681 This was withDamaris Cudworth, daughter of the Cambridge Platonist, RalphCudworth, and herself to become a philosopher of real ability Notsurprisingly, she was much more sympathetic to the Cambridgeschool than was Locke, and she was quite prepared to engage him inphilosophical exchange as an equal and later to publish her ownphilosophy They were evidently strongly attracted to one another,but Locke’s departure for Holland in 1683 broke their personalcontact, and whilst he was away she married Sir Francis Mashamand moved to his home at Oates in Essex At their invitation, Lockewas to spend his last years there as their paying guest It is nosurprise that Masham was herself much more influenced by HenryMore, John Smith, and her own father than was Locke, but there can

be no doubt that Locke’s contact with her made him more aware oftheir philosophical positions and more sympathetic to them than hemight otherwise have been But it is also true that Locke could notbut be aware of them because they were collectively the mostinteresting philosophers in England in the middle decades of thecentury.8

8

On Locke’s relationship to the Cambridge group, see Rogers forthcoming.