Ignorance: A Case for Scepticism (Clarendon Library of Logic & Philosophy)

336 Pages·1979·1.11 MB·English

by  Peter Unger

Ignorance
Clarendon Library of Logic and Philosophy
General Editor: L. Jonathan Cohen
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Ignorance
A Case for Scepticism
Peter Unger
2002
GreatClarendonStreet,OxfordOX26DP
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LibraryofCongressCataloging-in-PublicationData
Unger,PeterK.
Ignorance:acaseforscepticism/ PeterUnger
p.cm.
Originallypublished:Oxford:ClarendonPress,1975, inseries:
Clarendonlibraryoflogicandphilosophy
Includesbibliographicalreferencesandindex.
ISBN0-19-824417-7(pbk.)
1.Ignorance(Theoryof knowledge)2, Skepticism.1.Title.
BD221.U53 2002
121—dc212002019103
For
Sidney and Naomi Unger,
my father and mother
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Preface
In philosophy, being a sceptic usually means walking a lonely road. It has been my good fortune, however, to have
enjoyed serious conversation with a good many friends, critical but encouraging. Their challenges to my sceptical
offerings were important eventsin my coming to produce the present work. While I risk omittingthenames of some
who should be mentioned, I cannot but take pleasure in now thankingthose whose names come to mind. First, as in
all my philosophical work, I am indebted, for the model they have set me, to my former tutors, Professor Sir Alfred
Jules Ayer and Professor Peter F. Strawson. I have also learned much from association with these following
philosophers, to whom I am grateful: William Barrett, George Boolos, Fred Dretske, Bruce Freed, David Lewis,
Thomas Nagel,CharlesParsons, HilaryPutnam, James Rachels, SydneyShoemaker andDennisStampe.Thelinguists,
D. Terence Langendoen and Barbara Partee, are also to be thanked for instructive conversations.
Thereareafew peoplewhomImustsingleoutforspecialthanks.SaulKripkehashadagreatinfluenceonthepresent
work,especiallyas regards Chapters 1, 3 and 5. IdoubtthatChapter 4 wouldhavebeenofmuchinterestat allbutfor
formative conversations with Robert Gordon. And, without suggestions from Donald Davidson, Chapter 6 would
have been very different indeed, and very much poorer. In the actual writing of the manuscript, during 1973–4,
scarcelyanythingcamefrom myhand thatwas notread andusefullycriticizedbythreegoodfriends: GilbertHarman,
MichaelSlote,andJohnTaurek.Inlargemeasure,thisfinishedproductisanoutcomeofmydialogueswiththesethree
talented philosophers.
This book is, in rather large measure, based on seven papers of mine that appear elsewhere. By the same token, these
papers were written with such a book in mind; in retrospect, they may be regarded as studies for it. For kind
permission to reprint this material, I thank the editors and publishers of the following volumes, where these papers
appear: ‘A Defense of Skepticism’,
viii PREFACE
The Philosophical Review, vol. lxxx, No. 2 (April, 1971) forms the basis of Chapter 2 of the present work. Much of
Chapter 3 consists of material originally published as ‘An Argument for Skepticism’, Philosophic Exchange, vol. 1, No. 5
(Summer, 1974). Some of the material in Chapter 4 appeared as ‘Propositional Verbs and Knowledge’, The Journal of
Philosophy, vol. lxix, No. 11 (June 1, 1972). Some of the rest, in that same chapter, appeared as ‘The Wages of
Scepticism’, American Philosophical Quarterly, vol. 10, No. 3 (July, 1973). The fifth chapter contains material from my
paper ‘Two Types of Scepticism’, Philosophical Studies, vol. 25, No. 2 (February, 1974). Certain material in Chapter 6
appears in ‘A Skeptical Problem About Representation’, beingmy contributionto Forms of Representation: The Proceedings
of the1972 Philosophy Colloquium of the Universityof Western Ontario (1975), edited by B. Freed, A. Márras and P. Maynard,
and published by North-Holland Publishing Company. Finally, Chapter 7 includes material originally published in my
paper ‘Truth’, in Semantics and Philosophy, edited by Milton K. Munitz and myself, and published by the New York
University Press in 1974.
Thesustainedessay,whilebasedonthese priorstudies,tooktimeandeffort.For thetimeinwhichtomaketheeffort,
IammostgratefultotheJohnSimonGuggenheimMemorialFoundation.BygrantingmeagenerousFellowship,they
allowed me to spend the academic year of 1973–4 absorbed in the writing of my case for scepticism.
Finally, Ithank myphilosopher-typist,Mrs. SusanHank, forher patientlymaking a legibleworkofthepagesofscrawl
she received from me. The moral support provided by her, and her husband Daniel, is something I will always
remember with thanks.
New York City
October 1974
Contents
INTRODUCTION 1
I. A CLASSICAL FORM OF SCEPTICAL ARGUMENT 7
§1. Some Problems in Stating a Sceptical Thesis and some Steps towards their Resolution 10
§2. An Argument Concerning the External World 13
§3. The Essential Reasoning 14
§4. The Assumption of Reasoning 15
§5. Some Cartesian Complications 17
§6. A Unified Statement of the Argument 20
§7. How Further Complications Place Limits on this Argument 21
§8. On Trying to Reverse this Argument: Exotic Cases and Feelings of Irrationality 24
§9. Ordinary Cases and these same Feelings 28
§10. The Explanatory Power of the Attitude of Certainty 30
§11. The Retreat to Reasonable Believing: A Complex of Arguments and Problems 36
§12. An Argument concerning Other Times 40
§13. How much Alleged Knowledge can this Form of Argument Compellingly Exclude? 44
II. A LANGUAGE WITH ABSOLUTE TERMS 47
§1. Sophisticated Worries about what Scepticism Requires 50
§2. Absolute Terms and Relative Terms 54
§3. On Certainty and Certain Related Things 62
§4. The Doubtful Applicability of some Absolute Terms 65
§5. Meaning and Use 68
§6. Understanding, Learning, and Paradigm Cases 70
§7. How Better to Focus on Actual Meaning 74
§8. A Method, a Principle, and some Auxiliary Aids to getting Proper Focus 80
§9. Does Knowing Require Being Certain? 83
§10. Closing our Defence and Opening a New Argument 87
III. AN ARGUMENT FOR UNIVERSAL IGNORANCE 92
§1. A Preliminary Statement of the Argument 95
§2. The First Premiss: The Idea that if one Knows it is all right for one to be Certain 98
§3. The Second Premiss: The Idea that it is never all right to be Absolutely Certain 103
§4. What Attitude is Involved in one's being Absolutely Certain? 105
§5. The Attitude of Certainty and the Absoluteness of ‘Certain’ 114