Wittgeannstdth eVeii ne nCniar cle conversarteicoonrsbd ye d FriedWraiicshm ann Edited by Brian McGuinness Translated by Joachim Schulte and Brian McGuinness BOOKS 10 53d St.. York 10022 East New diviolsi Honar per& R ow Publi$hersI.nc . Published in the U.S.A. by Harper and Row Publishers, Inc., Barnes & Noble Import ·Pivision @ Basil Blackwell, 1979 All rights reserved. No pan of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior permission of the publisher. ISBN 0-06-497310-7 Library of Congress Catalog Number 78-6452 Printed in Great Britain CONTENTS Wittgensteciint-eWdo rks 10 EditPoerrfa'cse 1 l I 33 Wednesday, 18 December 1929 (at Schlick's house) (PrionoM fa thematics) 33 WhaDto eLoosk infgo Sro metMheianingnM athema3t4i cs? Example: Trisection of an Angle 36 Simile: Unravelling a Knot 3 7 Geomeast Sryyn tI ax 38 ConstiecsnyI 38 38 Sunday, 22 December 1929 (at Sch/ick's house) ('AIl)l ' 38 Objects 41 What Does 'All' Mean? 44 Solipsism 45 The Sense of a Proposition is its Verification 47 Wheels Turning Idly 48 ('cIa nnfoeyteo lup ra in') 49 (LanguaangWdeo rld) 50 Wednesday, 25 December (at Schlick's house) 51 'AlIlI' 51 Time 53 External-Internal 54 VisSuapla ce 55 Addendum, 30 December 1929 59 Geometasry S yntIaIx 61 PhysaincPdsh eneonmology 63 Colour-System 63 Is Every Proposition Part of a System? I 65 (The World is Red I) 65 66 Addendum, Monday, 30 December 1929 Anti-Husserl 67 68 Monday, 30 December 1929 (at Schlick's house) Apropos of Heidegger 68 Dedekindian Definition 69 Real Numbers I 71 73 Thursday, 2 January 1930 (at Schlick's house) (Elementary Propositions) 73 ('The Present State of Knowledge in Mathematics') 81 83 Freely developing sequence 84 (Miscellaneous) 84 Sunday, 5 January 1930 (at Schlick's house) Positive and Negative Propositions 84 The Colour Blue in Memory 87 'The World is Red' II 88 Is Every Proposition Part of a System? II 89 Inference 91 Lecture on Ethics 92 Probability I 9 3 Dice 95 II 97 22 March 1930 (at Schlick's house) (Verification and the Immediately Given) 97 98 (Verification and Time) Probability II 98 Hypotheses I 99 100 Double Meaning of Geometry 101 (Various Remarks about Hypotheses) III 102 19 June 1930 (at Schlick's house) (What to Say at Konigsberg) 102 103 Formalism 105 Equation and Tautology 6 I 25 September 1930 107 107 108 (Miscaenelal) Proof 109 Variables 109 113 ReaNlu mberIsI 113 Idealization Interpretation IV Wednesday, 17 December 1930 (Neuwaldegg) 115 115 115 OnSc hlicEkt'hsi cs 117 Valeu 118 Religion 119 Ought ConsisItIe ncy Friday, 26 December 1930 (at Schlicle's house) 121 121 StyolfTe h inking Sunday, 28 December 1930 (at Schlick's house) 121 121 Sheffer's DiscMJery 122 ConsisItIeIn cy (Rules and Configurations of a Game) 123 What Does it Mean to Apply a Calculus? 126 128 (InddeepneeIc n) Tuesday, 30 December 1930 (at Schlicle's house) 130 130 (Frege and Wittgenstein I) 130 (ConsiIsVt)e ncy Hilbert's Proof 137 Thursday, 1 January 1931 (at Schlicle's house) 142 America. The Institution of Colleges 142 142 Independence II 145 ConsisVt ency Summary 148 Hilbert's Axioms 1.1 and I. 2 148 7 (Calculus and Everday Prose) 149 Frege and Wittgenstein II 150 Sunday, 4 January 1931 (at Schlick's house) 152 (Equation and Substitution-Rule I) 152 (Equation and Tautology) 158 (Verification of the Propositions of Physics) 158 Hypotheses II 159 162 (GeorMtry as Syntax Addenda 163 II) Chess 163 Apropos of Konigsberg 164 Definition of Number 164 V Monday, 21 September 1931 (first Argentinierstrasse, then in the street) 166 Intention, to Mean, Meaning 166 (Calculus and Application) 170 (Looking Things Up in a Diary) 171 Constructing a Boiler 171 Proof of Existence 17 2 (Consistency VI) 173 Hidden Contradiction 173 Contradiction 175 (Equation and Substitution-rule II) 178 Indirect Proof I 179 VI Wednesday, 9 December 1931 (Neuwaldegg ) 182 On Dogmatism 182 On Infinity 187 On Ramsey's Definition of Identity 189 Consistency VIII 192 8 Insertion from dictation 196 Consistency VIII 196 An Ana/ogy-'The Expansion' of 201 (The Concept of a Calculw) 202 (Proof in Geometry and Arithmetic) 203 Bisection of an Angle 204 Generality in Geometry 206 Indirect Proof II 207 VII 1 July 1932 (A rgentinierstrasse) 209 Hypotheses III 210 Appendix A Totality and System 213 Equation and Tautology 218 Concept and Form 220 What is a Number? 221 Sense and Meaning 227 On Infinity 227 Dedekind's Definition 232 Appendix B Theses by Friedrich Waismann (ca. 1930) 233 I. States of Affairs, Facts, Reality 233 2. Language 235 3. Syntax 239 4. Symmetry, Asym"1etry 241 5. Identity 242 6. Verification 243 7. Definition 246 8. Objects 254 9. Logical Space 260 Index 263 9 WITTGENSTEWIONR:K SC ITED Approximate Abbrevia date of com tion position NL Notes on Logic (Notebooks 1914-1916, 1913 Oxfo1r9d16 ,p p9.3 -106) Nh Notehooks (ibipdp.2.,- 91) 191-41917 TLP Tractatus Logico-Philosophicus (firpsutb lis1h9e1d8 -1919 as Logisch-Phi/osophische Abhand/ung, latest editLoinodno,1n 9 71) LE 'LectuorneE thi(cPhsil·oso phical Review 1929 lxxi(v1 96p5p).3, - 12) MS vol/. Manuscrviopltu m1e-sX( unpublish1e9d2)9 -1932 PR Philosophical Remarks (Oxfo1r9d7 5fi,r st1 930 publisahseP dhil osophische Bemerkungen, Oxforadn dF rankfu1rt9 65{)c ontains materfrioamMl S v ol1l-.1a 1n1pd a rotfM S volI.V ] EM Extracfrto mt hMean uscripvto lum(eusn -1931-1932 publis{hate ydpe)s corfi7 p7t0p agesc;o n- taimnast erfrioamMl S v olVl-.I X] BT The 'BiTgy pesc(ruinpptu'b l{iats yhpee-d1)9 32 scroifp7 t6 8pa ges;c ontamiantse rfrioaml EM ando thseirm ielxatrr aacrtrasn,gi end sectiaonndcs h apters] GdM Grundlagen der Mathematik {thleas t2 40 1932 pageso fBT ; fotrh meo spta rptu bliisnh ed PG) PG Philosophical Grammar (Oxfo1r9d7 4fi,r st1 932-1936 publisas� ePdhi losophische Grammatik, Oxforda ndF rankfurt1 969{)c ontGaidMn s andr eworkoifon tghspe arr otfBs TI RFM Remarks on the Foundations of Mathematics 1937-1942 (Oxfor1d9 5ful6l,e edri tiaso Bnemw leungen iiber die Grundlagen der Mathematik, Frank- furt 1974) Pl Philosophical Investigations (Oxfo1r9d5 3) 19379-419 IO EDITOR'S PREFACE I The material translated in the present volume is practically all drawn from the papers of the late Friedrich Waismann (1 897-1959). The exceptions are a few pages missing from Waismann's own copy of his Theses (Appendix B), which were supplied by Dr. Josef Schachter of Jerusalem, and some sections of the notes on the philosophy of mathematics (Appendix A), which exist only in the form of extracts made by Mr. Shimshon Stein, now of Tel Aviv. It was all first published in the original German jointly by the present publishers and by Suhrkamp of Frankfurt in 1967. The present edition follows as nearly as possible the pagination of that one. None of the material can be described without qualification as Waismann's own work. All of it originated at a time when Wittgen stein, though with considerable misgivings, was willing to see his ideas propagated at any rate in Vienna by means of reports composed by Waismann. Gradually, however, as we shall see, he became dissatisfied with this method and had recourse to full collaboration with Waismann. When that too proved unsatisfactory, it seems that his philosophical ideas were communicated to his Viennese friends for the most part as a result of his meetings with Schlick and through the despatch of copies of the Blue Book and other dictated notes. Waismann, for his part, was able to incorporated many of Witt genstein's ideas on the philosophy of mathematics into his own Einfiihrung in das mathematirche Denken (lntroduaion to Mathematica/ thinking), 1 which first appeared in 1936 and is of course essentially a work of Waismann's. But his book Logik, Sprache, Phi/osophie (Logic, Language, Philosophy), which had been announced several times be tween 1929 and 1931, never appeared in Waismann's lifetime, despite or because of frequent revisions. It was finally published in 1 Vienna 1936, 21947, 3Munich 1950; E. T. New York 1951. Wittgenstein·s contribution to this work is described in detail in an appendix. II Principles translation six years after Waismann•s death under the title of Linguistic Philosophy2 in a form much altered from the original concepcmn. II The earliest material published in the main part of this volume consists of the record of a conversation that took place in December 1929. Wittgenstein had spent that year in Cambridge: his return to philosophy as his main occupation can be dated to that time. But, as might be expected, there were several occasions earlier in the twenties when his interest in the subject began to revive, whether stimulated by others or of its own accord. F. P. Ramsey visited him several times in 1923 and also in 1924 over a period of six or seven months. The two Tractatus men discussed the and Wittgenstein proposed a number of changes in the English translation, which were in fact adopted for the 3 second edition. They also talked about the foundations of mathema tics and about the changes to be wished for in a second edition of Principia Mathematica. On 24 March 1924, however, Ramsay wrote to Keynes saying that Wittgenstein obviously found thinking to be uphill work and needed someone like Ramsey himself to stimulate 4 (4 him. Wirtgensrein later July 1924) wrote to Keynes saying, 'You ask in your letter whether you could do anything to make it possible for me to return co scientific work. The answer is, No: there's nothing that can be done in that line, because I myself no longer have any strong inner drive towards that sort of activity. Eve thing that I ry had really to say, I have said, and so the spring has run d . That ry sounds queer, but it•s how things are., There the matter rested for the moment. A plan to induce Wittgenstein to spend in Cambridge the remainder of the time necessa to qualify him for a doctorate was ry 2 London, 1965. The German original was later published under the title Logik, Sprache, Phi/oJophie, Stuttgart, 1976, with some account of the genesis of the work, for which see also Section IV below. 3 See C. Lewy·s ·Note on the text of the TractatuJ· in Mind 76(1967)416-423. 4 See L. Wittgenstein, Letters to Rwse/1, Keynes and Moon, pp. 114-118, for both Ramsey· s and Wittgenstein· s letters at this time. 12