TheLogicofScientificDiscovery‘Oneofthemostimportantphilosophicalworksofourcentury.’RichardWollheim,TheObserver‘Wonderfullyexhilarating.’NaomiBliven,NewYorkerKarlPopperTheLogicofScientificDiscoveryLondonandNewYorkLogikderForschungfirstpublished1935byVerlagvonJuliusSpringer,Vienna,AustriaFirstEnglisheditionpublished1959byHutchinson&Co.FirstpublishedbyRoutledge1992FirstpublishedinRoutledgeClassics2002byRoutledge11NewFetterLane,LondonEC4P4EE29West35thStreet,NewYork,NY10001RoutledgeisanimprintoftheTaylor&FrancisGroupThiseditionpublishedintheTaylor&Francise-Library,2005.“TopurchaseyourowncopyofthisoranyofTaylor&FrancisorRoutledge’scollectionofthousandsofeBookspleasegotowww.eBookstore.tandf.co.uk.”©1959,1968,1972,1980KarlPopper©1999,2002TheEstateofKarlPopperAllrightsreserved.Nopartofthisbookmaybereprintedorreproducedorutilisedinanyformorbyanyelectronic,mechanical,orothermeans,nowknownorhereafterinvented,includingphotocopyingandrecording,orinanyinformationstorageorretrievalsystem,withoutpermissioninwritingfromthepublishers.BritishLibraryCataloguinginPublicationDataAcataloguerecordforthisbookisavailablefromtheBritishLibraryLibraryofCongressCataloginginPublicationDataAcataloguerecordforthisbookhasbeenrequestedISBN0-203-99462-0Mastere-bookISBNISBN0–415–27843–0(hbk)ISBN0–415–27844–9(pbk)TOMYWIFEwhoisresponsiblefortherevivalofthisbookCONTENTSTranslators’NotexiiPrefacetotheFirstEdition,1934xvPrefacetotheFirstEnglishEdition,1959xviiiPARTIIntroductiontotheLogicofScience1ASurveyofSomeFundamentalProblems31TheProblemofInduction2EliminationofPsychologism3DeductiveTestingofTheories4TheProblemofDemarcation5ExperienceasaMethod6FalsifiabilityasaCriterionofDemarcation7TheProblemofthe‘EmpiricalBasis’8ScientificObjectivityandSubjectiveConviction2OntheProblemofaTheoryofScientificMethod279WhyMethodologicalDecisionsareIndispensable10TheNaturalisticApproachtotheTheoryofMethod11MethodologicalRulesasConventionsviiicontents