CINXE.COM

<!DOCTYPE html> <html class="client-nojs vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-disabled skin-theme-clientpref-day vector-sticky-header-enabled vector-toc-available" lang="en" dir="ltr"> <head> <meta charset="UTF-8"> <title>Karl Popper - Simple English Wikipedia, the free encyclopedia</title> <script>(function(){var className="client-js vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-disabled skin-theme-clientpref-day vector-sticky-header-enabled vector-toc-available";var cookie=document.cookie.match(/(?:^|; )simplewikimwclientpreferences=([^;]+)/);if(cookie){cookie[1].split('%2C').forEach(function(pref){className=className.replace(new RegExp('(^| )'+pref.replace(/-clientpref-\w+$|[^\w-]+/g,'')+'-clientpref-\\w+( |$)'),'$1'+pref+'$2');});}document.documentElement.className=className;}());RLCONF={"wgBreakFrames":false,"wgSeparatorTransformTable":["",""],"wgDigitTransformTable":["",""],"wgDefaultDateFormat":"dmy", "wgMonthNames":["","January","February","March","April","May","June","July","August","September","October","November","December"],"wgRequestId":"a9ef43ce-068f-480a-812a-4a6798acbef4","wgCanonicalNamespace":"","wgCanonicalSpecialPageName":false,"wgNamespaceNumber":0,"wgPageName":"Karl_Popper","wgTitle":"Karl Popper","wgCurRevisionId":9598536,"wgRevisionId":9598536,"wgArticleId":98456,"wgIsArticle":true,"wgIsRedirect":false,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":["Articles with hCards","Webarchive template wayback links","Articles with FAST identifiers","Articles with ISNI identifiers","Articles with VIAF identifiers","Articles with WorldCat Entities identifiers","Articles with BIBSYS identifiers","Articles with BNC identifiers","Articles with BNE identifiers","Articles with BNF identifiers","Articles with BNFdata identifiers","Articles with CANTICN identifiers","Articles with GND identifiers","Articles with ICCU identifiers", "Articles with J9U identifiers","Articles with KANTO identifiers","Articles with KBR identifiers","Articles with LCCN identifiers","Articles with Libris identifiers","Articles with LNB identifiers","Articles with NDL identifiers","Articles with NKC identifiers","Articles with NLA identifiers","Articles with NLG identifiers","Articles with NLK identifiers","Articles with NSK identifiers","Articles with NTA identifiers","Articles with PLWABN identifiers","Articles with VcBA identifiers","Articles with CINII identifiers","Articles with MATHSN identifiers","Articles with MGP identifiers","Articles with Scopus identifiers","Articles with ZBMATH identifiers","Articles with MusicBrainz identifiers","Articles with RKDartists identifiers","Articles with ULAN identifiers","Articles with DTBIO identifiers","Articles with Trove identifiers","Articles with SNAC-ID identifiers","Articles with SUDOC identifiers","1902 births","1994 deaths","20th-century British philosophers","Austrian academics", "Austrian Jews","Austrian scientists","Austrian writers","Companions of Honour","Fellows of the Royal Society","Jewish British academics","Jewish British scientists","Jewish British writers","Jewish philosophers","Knights Bachelor","Naturalised citizens of the United Kingdom","Refugees from Nazism","Scientists from Vienna","Austrian philosophers"],"wgPageViewLanguage":"en","wgPageContentLanguage":"en","wgPageContentModel":"wikitext","wgRelevantPageName":"Karl_Popper","wgRelevantArticleId":98456,"wgIsProbablyEditable":true,"wgRelevantPageIsProbablyEditable":true,"wgRestrictionEdit":[],"wgRestrictionMove":[],"wgNoticeProject":"wikipedia","wgCiteReferencePreviewsActive":false,"wgMediaViewerOnClick":true,"wgMediaViewerEnabledByDefault":true,"wgPopupsFlags":0,"wgVisualEditor":{"pageLanguageCode":"en","pageLanguageDir":"ltr","pageVariantFallbacks":"en"},"wgMFDisplayWikibaseDescriptions":{"search":true,"watchlist":true,"tagline":true,"nearby":true},"wgWMESchemaEditAttemptStepOversample":false ,"wgWMEPageLength":10000,"wgEditSubmitButtonLabelPublish":true,"wgULSPosition":"interlanguage","wgULSisCompactLinksEnabled":false,"wgVector2022LanguageInHeader":true,"wgULSisLanguageSelectorEmpty":false,"wgWikibaseItemId":"Q81244","wgCheckUserClientHintsHeadersJsApi":["brands","architecture","bitness","fullVersionList","mobile","model","platform","platformVersion"],"GEHomepageSuggestedEditsEnableTopics":true,"wgGETopicsMatchModeEnabled":false,"wgGEStructuredTaskRejectionReasonTextInputEnabled":false,"wgGELevelingUpEnabledForUser":false};RLSTATE={"ext.globalCssJs.user.styles":"ready","site.styles":"ready","user.styles":"ready","ext.globalCssJs.user":"ready","user":"ready","user.options":"loading","ext.cite.styles":"ready","skins.vector.search.codex.styles":"ready","skins.vector.styles":"ready","skins.vector.icons":"ready","jquery.makeCollapsible.styles":"ready","ext.wikimediamessages.styles":"ready","ext.visualEditor.desktopArticleTarget.noscript":"ready","ext.uls.interlanguage":"ready" ,"wikibase.client.init":"ready","ext.wikimediaBadges":"ready"};RLPAGEMODULES=["ext.cite.ux-enhancements","site","mediawiki.page.ready","jquery.makeCollapsible","mediawiki.toc","skins.vector.js","ext.centralNotice.geoIP","ext.centralNotice.startUp","ext.gadget.ReferenceTooltips","ext.gadget.refToolbar","ext.gadget.switcher","ext.urlShortener.toolbar","ext.centralauth.centralautologin","mmv.bootstrap","ext.popups","ext.visualEditor.desktopArticleTarget.init","ext.visualEditor.targetLoader","ext.echo.centralauth","ext.eventLogging","ext.wikimediaEvents","ext.navigationTiming","ext.uls.interface","ext.cx.eventlogging.campaigns","ext.cx.uls.quick.actions","wikibase.client.vector-2022","ext.checkUser.clientHints","ext.growthExperiments.SuggestedEditSession"];</script> <script>(RLQ=window.RLQ||[]).push(function(){mw.loader.impl(function(){return["user.options@12s5i",function($,jQuery,require,module){mw.user.tokens.set({"patrolToken":"+\\","watchToken":"+\\","csrfToken":"+\\"}); }];});});</script> <link rel="stylesheet" href="/w/load.php?lang=en&modules=ext.cite.styles%7Cext.uls.interlanguage%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediaBadges%7Cext.wikimediamessages.styles%7Cjquery.makeCollapsible.styles%7Cskins.vector.icons%2Cstyles%7Cskins.vector.search.codex.styles%7Cwikibase.client.init&only=styles&skin=vector-2022"> <script async="" src="/w/load.php?lang=en&modules=startup&only=scripts&raw=1&skin=vector-2022"></script> <meta name="ResourceLoaderDynamicStyles" content=""> <link rel="stylesheet" href="/w/load.php?lang=en&modules=site.styles&only=styles&skin=vector-2022"> <meta name="generator" content="MediaWiki 1.44.0-wmf.17"> <meta name="referrer" content="origin"> <meta name="referrer" content="origin-when-cross-origin"> <meta name="robots" content="max-image-preview:standard"> <meta name="format-detection" content="telephone=no"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/4/43/Karl_Popper.jpg"> <meta property="og:image:width" content="1200"> <meta property="og:image:height" content="1538"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/4/43/Karl_Popper.jpg"> <meta property="og:image:width" content="800"> <meta property="og:image:height" content="1025"> <meta property="og:image:width" content="640"> <meta property="og:image:height" content="820"> <meta name="viewport" content="width=1120"> <meta property="og:title" content="Karl Popper - Simple English Wikipedia, the free encyclopedia"> <meta property="og:type" content="website"> <link rel="preconnect" href="//upload.wikimedia.org"> <link rel="alternate" media="only screen and (max-width: 640px)" href="//simple.m.wikipedia.org/wiki/Karl_Popper"> <link rel="alternate" type="application/x-wiki" title="change this page" href="/w/index.php?title=Karl_Popper&action=edit"> <link rel="apple-touch-icon" href="/static/apple-touch/wikipedia.png"> <link rel="icon" href="/static/favicon/wikipedia.ico"> <link rel="search" type="application/opensearchdescription+xml" href="/w/rest.php/v1/search" title="Wikipedia (en)"> <link rel="EditURI" type="application/rsd+xml" href="//simple.wikipedia.org/w/api.php?action=rsd"> <link rel="canonical" href="https://simple.wikipedia.org/wiki/Karl_Popper"> <link rel="license" href="https://creativecommons.org/licenses/by-sa/4.0/deed.simple"> <link rel="alternate" type="application/atom+xml" title="Wikipedia Atom feed" href="/w/index.php?title=Special:RecentChanges&feed=atom"> <link rel="dns-prefetch" href="//meta.wikimedia.org" /> <link rel="dns-prefetch" href="login.wikimedia.org"> </head> <body class="skin--responsive skin-vector skin-vector-search-vue mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject mw-editable page-Karl_Popper rootpage-Karl_Popper skin-vector-2022 action-view"><a class="mw-jump-link" href="#bodyContent">Jump to content</a> <div class="vector-header-container"> <header class="vector-header mw-header"> <div class="vector-header-start"> <nav class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-dropdown" class="vector-dropdown vector-main-menu-dropdown vector-button-flush-left vector-button-flush-right" title="Main menu" > <input type="checkbox" id="vector-main-menu-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-main-menu-dropdown" class="vector-dropdown-checkbox " aria-label="Main menu" > <label id="vector-main-menu-dropdown-label" for="vector-main-menu-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-menu mw-ui-icon-wikimedia-menu"></span> <span class="vector-dropdown-label-text">Main menu</span> </label> <div class="vector-dropdown-content"> <div id="vector-main-menu-unpinned-container" class="vector-unpinned-container"> <div id="vector-main-menu" class="vector-main-menu vector-pinnable-element"> <div class="vector-pinnable-header vector-main-menu-pinnable-header vector-pinnable-header-unpinned" data-feature-name="main-menu-pinned" data-pinnable-element-id="vector-main-menu" data-pinned-container-id="vector-main-menu-pinned-container" data-unpinned-container-id="vector-main-menu-unpinned-container" > <div class="vector-pinnable-header-label">Main menu</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-main-menu.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-main-menu.unpin">hide</button> </div> <div id="p-navigation" class="vector-menu mw-portlet mw-portlet-navigation" > <div class="vector-menu-heading"> Getting around </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-mainpage-description" class="mw-list-item"><a href="/wiki/Main_Page" title="Visit the main page [z]" accesskey="z"><span>Main page</span></a></li><li id="n-portal" class="mw-list-item"><a href="/wiki/Wikipedia:Simple_start" title="About the project, what you can do, where to find things"><span>Simple start</span></a></li><li id="n-Simple-talk" class="mw-list-item"><a href="/wiki/Wikipedia:Simple_talk"><span>Simple talk</span></a></li><li id="n-recentchanges" class="mw-list-item"><a href="/wiki/Special:RecentChanges" title="The list of new changes in the wiki. [r]" accesskey="r"><span>New changes</span></a></li><li id="n-randompage" class="mw-list-item"><a href="/wiki/Special:Random" title="Show any page [x]" accesskey="x"><span>Show any page</span></a></li><li id="n-help" class="mw-list-item"><a href="/wiki/Help:Contents" title="The place to get help"><span>Help</span></a></li><li id="n-contactpage" class="mw-list-item"><a href="//simple.wikipedia.org/wiki/Wikipedia:Contact_us"><span>Contact us</span></a></li><li id="n-aboutsite" class="mw-list-item"><a href="/wiki/Wikipedia:About"><span>About Wikipedia</span></a></li><li id="n-specialpages" class="mw-list-item"><a href="/wiki/Special:SpecialPages"><span>Special pages</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> <a href="/wiki/Main_Page" class="mw-logo"> <img class="mw-logo-icon" src="/static/images/icons/wikipedia.png" alt="" aria-hidden="true" height="50" width="50"> <span class="mw-logo-container skin-invert"> <img class="mw-logo-wordmark" alt="Wikipedia" src="/static/images/mobile/copyright/wikipedia-wordmark-en.svg" style="width: 7.5em; height: 1.125em;"> <img class="mw-logo-tagline" alt="The Free Encyclopedia" src="/static/images/mobile/copyright/wikipedia-tagline-simple.svg" width="101" height="18" style="width: 6.3125em; height: 1.125em;"> </span> </a> </div> <div class="vector-header-end"> <div id="p-search" role="search" class="vector-search-box-vue vector-search-box-collapses vector-search-box-show-thumbnail vector-search-box-auto-expand-width vector-search-box"> <a href="/wiki/Special:Search" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only search-toggle" title="Search Wikipedia [f]" accesskey="f"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>Search</span> </a> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail cdx-typeahead-search--auto-expand-width"> <form action="/w/index.php" id="searchform" class="cdx-search-input cdx-search-input--has-end-button"> <div id="simpleSearch" class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Search Wikipedia" aria-label="Search Wikipedia" autocapitalize="sentences" title="Search Wikipedia [f]" accesskey="f" id="searchInput" > <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="Special:Search"> </div> <button class="cdx-button cdx-search-input__end-button">Search</button> </form> </div> </div> </div> <nav class="vector-user-links vector-user-links-wide" aria-label="Personal tools"> <div class="vector-user-links-main"> <div id="p-vector-user-menu-preferences" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-userpage" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-dropdown" class="vector-dropdown " title="Change the appearance of the page's font size, width, and color" > <input type="checkbox" id="vector-appearance-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-appearance-dropdown" class="vector-dropdown-checkbox " aria-label="Appearance" > <label id="vector-appearance-dropdown-label" for="vector-appearance-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-appearance mw-ui-icon-wikimedia-appearance"></span> <span class="vector-dropdown-label-text">Appearance</span> </label> <div class="vector-dropdown-content"> <div id="vector-appearance-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div id="p-vector-user-menu-notifications" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-overflow" class="vector-menu mw-portlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="https://donate.wikimedia.org/?wmf_source=donate&wmf_medium=sidebar&wmf_campaign=simple.wikipedia.org&uselang=en" class=""><span>Give to Wikipedia</span></a> </li> <li id="pt-createaccount-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:CreateAccount&returnto=Karl+Popper" title="You are encouraged to create an account and log in; however, it is not mandatory" class=""><span>Create account</span></a> </li> <li id="pt-login-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:UserLogin&returnto=Karl+Popper" title="You are encouraged to log in; however, it is not mandatory [o]" accesskey="o" class=""><span>Log in</span></a> </li> </ul> </div> </div> </div> <div id="vector-user-links-dropdown" class="vector-dropdown vector-user-menu vector-button-flush-right vector-user-menu-logged-out" title="More options" > <input type="checkbox" id="vector-user-links-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-user-links-dropdown" class="vector-dropdown-checkbox " aria-label="Personal tools" > <label id="vector-user-links-dropdown-label" for="vector-user-links-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-ellipsis mw-ui-icon-wikimedia-ellipsis"></span> <span class="vector-dropdown-label-text">Personal tools</span> </label> <div class="vector-dropdown-content"> <div id="p-personal" class="vector-menu mw-portlet mw-portlet-personal user-links-collapsible-item" title="User menu" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport" class="user-links-collapsible-item mw-list-item"><a href="https://donate.wikimedia.org/?wmf_source=donate&wmf_medium=sidebar&wmf_campaign=simple.wikipedia.org&uselang=en"><span>Give to Wikipedia</span></a></li><li id="pt-createaccount" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:CreateAccount&returnto=Karl+Popper" title="You are encouraged to create an account and log in; however, it is not mandatory"><span class="vector-icon mw-ui-icon-userAdd mw-ui-icon-wikimedia-userAdd"></span> <span>Create account</span></a></li><li id="pt-login" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:UserLogin&returnto=Karl+Popper" title="You are encouraged to log in; however, it is not mandatory [o]" accesskey="o"><span class="vector-icon mw-ui-icon-logIn mw-ui-icon-wikimedia-logIn"></span> <span>Log in</span></a></li> </ul> </div> </div> <div id="p-user-menu-anon-editor" class="vector-menu mw-portlet mw-portlet-user-menu-anon-editor" > <div class="vector-menu-heading"> Pages for logged out editors <a href="/wiki/Help:Introduction" aria-label="Learn more about editing"><span>learn more</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/Special:MyContributions" title="A list of edits made from this IP address [y]" accesskey="y"><span>Contributions</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/Special:MyTalk" title="Discussion about changes from this IP address [n]" accesskey="n"><span>Talk</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="Contents" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">Contents</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">Beginning</div> </a> </li> <li id="toc-Life" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Life"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Life</span> </div> </a> <ul id="toc-Life-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Falsification" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Falsification"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Falsification</span> </div> </a> <ul id="toc-Falsification-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-The_open_society" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#The_open_society"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>The open society</span> </div> </a> <button aria-controls="toc-The_open_society-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle The open society subsection</span> </button> <ul id="toc-The_open_society-sublist" class="vector-toc-list"> <li id="toc-The_paradox_of_tolerance" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#The_paradox_of_tolerance"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1</span> <span>The paradox of tolerance</span> </div> </a> <ul id="toc-The_paradox_of_tolerance-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-The_Three_worlds_doctrine" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#The_Three_worlds_doctrine"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>The Three worlds doctrine</span> </div> </a> <ul id="toc-The_Three_worlds_doctrine-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Key_works" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Key_works"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Key works</span> </div> </a> <ul id="toc-Key_works-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Related_pages" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Related_pages"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Related pages</span> </div> </a> <ul id="toc-Related_pages-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Other_websites" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Other_websites"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Other websites</span> </div> </a> <ul id="toc-Other_websites-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" title="Table of Contents" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Karl Popper</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 91 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-91" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">91 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-af mw-list-item"><a href="https://af.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Afrikaans" lang="af" hreflang="af" data-title="Karl Popper" data-language-autonym="Afrikaans" data-language-local-name="Afrikaans" class="interlanguage-link-target"><span>Afrikaans</span></a></li><li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%83%D8%A7%D8%B1%D9%84_%D8%A8%D9%88%D8%A8%D8%B1" title="كارل بوبر – Arabic" lang="ar" hreflang="ar" data-title="كارل بوبر" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-an mw-list-item"><a href="https://an.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Aragonese" lang="an" hreflang="an" data-title="Karl Popper" data-language-autonym="Aragonés" data-language-local-name="Aragonese" class="interlanguage-link-target"><span>Aragonés</span></a></li><li class="interlanguage-link interwiki-as mw-list-item"><a href="https://as.wikipedia.org/wiki/%E0%A6%95%E0%A6%BE%E0%A7%B0%E0%A7%8D%E0%A6%B2_%E0%A6%AA%E0%A6%AA%E0%A6%BE%E0%A7%B0" title="কাৰ্ল পপাৰ – Assamese" lang="as" hreflang="as" data-title="কাৰ্ল পপাৰ" data-language-autonym="অসমীয়া" data-language-local-name="Assamese" class="interlanguage-link-target"><span>অসমীয়া</span></a></li><li class="interlanguage-link interwiki-ast mw-list-item"><a href="https://ast.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Asturian" lang="ast" hreflang="ast" data-title="Karl Popper" data-language-autonym="Asturianu" data-language-local-name="Asturian" class="interlanguage-link-target"><span>Asturianu</span></a></li><li class="interlanguage-link interwiki-gn mw-list-item"><a href="https://gn.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Guarani" lang="gn" hreflang="gn" data-title="Karl Popper" data-language-autonym="Avañe'ẽ" data-language-local-name="Guarani" class="interlanguage-link-target"><span>Avañe'ẽ</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Azerbaijani" lang="az" hreflang="az" data-title="Karl Popper" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-azb mw-list-item"><a href="https://azb.wikipedia.org/wiki/%DA%A9%D8%A7%D8%B1%D9%84_%D9%BE%D9%88%D9%BE%D8%B1" title="کارل پوپر – South Azerbaijani" lang="azb" hreflang="azb" data-title="کارل پوپر" data-language-autonym="تۆرکجه" data-language-local-name="South Azerbaijani" class="interlanguage-link-target"><span>تۆرکجه</span></a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%95%E0%A6%BE%E0%A6%B0%E0%A7%8D%E0%A6%B2_%E0%A6%AA%E0%A6%AA%E0%A6%BE%E0%A6%B0" title="কার্ল পপার – Bangla" lang="bn" hreflang="bn" data-title="কার্ল পপার" data-language-autonym="বাংলা" data-language-local-name="Bangla" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%9A%D0%B0%D1%80%D0%BB_%D0%9F%D0%BE%D0%BF%D0%B5%D1%80" title="Карл Попер – Belarusian" lang="be" hreflang="be" data-title="Карл Попер" data-language-autonym="Беларуская" data-language-local-name="Belarusian" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-be-x-old mw-list-item"><a href="https://be-tarask.wikipedia.org/wiki/%D0%9A%D0%B0%D1%80%D0%BB_%D0%9F%D0%BE%D0%BF%D1%8D%D1%80" title="Карл Попэр – Belarusian (Taraškievica orthography)" lang="be-tarask" hreflang="be-tarask" data-title="Карл Попэр" data-language-autonym="Беларуская (тарашкевіца)" data-language-local-name="Belarusian (Taraškievica orthography)" class="interlanguage-link-target"><span>Беларуская (тарашкевіца)</span></a></li><li class="interlanguage-link interwiki-bcl mw-list-item"><a href="https://bcl.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Central Bikol" lang="bcl" hreflang="bcl" data-title="Karl Popper" data-language-autonym="Bikol Central" data-language-local-name="Central Bikol" class="interlanguage-link-target"><span>Bikol Central</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%9A%D0%B0%D1%80%D0%BB_%D0%9F%D0%BE%D0%BF%D1%8A%D1%80" title="Карл Попър – Bulgarian" lang="bg" hreflang="bg" data-title="Карл Попър" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-bs mw-list-item"><a href="https://bs.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Bosnian" lang="bs" hreflang="bs" data-title="Karl Popper" data-language-autonym="Bosanski" data-language-local-name="Bosnian" class="interlanguage-link-target"><span>Bosanski</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Catalan" lang="ca" hreflang="ca" data-title="Karl Popper" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Czech" lang="cs" hreflang="cs" data-title="Karl Popper" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-cy mw-list-item"><a href="https://cy.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Welsh" lang="cy" hreflang="cy" data-title="Karl Popper" data-language-autonym="Cymraeg" data-language-local-name="Welsh" class="interlanguage-link-target"><span>Cymraeg</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Danish" lang="da" hreflang="da" data-title="Karl Popper" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – German" lang="de" hreflang="de" data-title="Karl Popper" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Estonian" lang="et" hreflang="et" data-title="Karl Popper" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%9A%CE%B1%CF%81%CE%BB_%CE%A0%CF%8C%CF%80%CE%B5%CF%81" title="Καρλ Πόπερ – Greek" lang="el" hreflang="el" data-title="Καρλ Πόπερ" data-language-autonym="Ελληνικά" data-language-local-name="Greek" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-en mw-list-item"><a href="https://en.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – English" lang="en" hreflang="en" data-title="Karl Popper" data-language-autonym="English" data-language-local-name="English" class="interlanguage-link-target"><span>English</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Spanish" lang="es" hreflang="es" data-title="Karl Popper" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Esperanto" lang="eo" hreflang="eo" data-title="Karl Popper" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Basque" lang="eu" hreflang="eu" data-title="Karl Popper" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%DA%A9%D8%A7%D8%B1%D9%84_%D9%BE%D9%88%D9%BE%D8%B1" title="کارل پوپر – Persian" lang="fa" hreflang="fa" data-title="کارل پوپر" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – French" lang="fr" hreflang="fr" data-title="Karl Popper" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Galician" lang="gl" hreflang="gl" data-title="Karl Popper" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%B9%BC_%ED%8F%AC%ED%8D%BC" title="칼 포퍼 – Korean" lang="ko" hreflang="ko" data-title="칼 포퍼" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/%D4%BF%D5%A1%D6%80%D5%AC_%D5%93%D5%B8%D6%83%D5%A5%D6%80" title="Կարլ Փոփեր – Armenian" lang="hy" hreflang="hy" data-title="Կարլ Փոփեր" data-language-autonym="Հայերեն" data-language-local-name="Armenian" class="interlanguage-link-target"><span>Հայերեն</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%B8%E0%A4%B0_%E0%A4%95%E0%A4%BE%E0%A4%B0%E0%A5%8D%E0%A4%B2_%E0%A4%AA%E0%A5%89%E0%A4%AA%E0%A4%B0" title="सर कार्ल पॉपर – Hindi" lang="hi" hreflang="hi" data-title="सर कार्ल पॉपर" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Croatian" lang="hr" hreflang="hr" data-title="Karl Popper" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-io mw-list-item"><a href="https://io.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Ido" lang="io" hreflang="io" data-title="Karl Popper" data-language-autonym="Ido" data-language-local-name="Ido" class="interlanguage-link-target"><span>Ido</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Indonesian" lang="id" hreflang="id" data-title="Karl Popper" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-ia mw-list-item"><a href="https://ia.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Interlingua" lang="ia" hreflang="ia" data-title="Karl Popper" data-language-autonym="Interlingua" data-language-local-name="Interlingua" class="interlanguage-link-target"><span>Interlingua</span></a></li><li class="interlanguage-link interwiki-is badge-Q17437798 badge-goodarticle mw-list-item" title="good article badge"><a href="https://is.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Icelandic" lang="is" hreflang="is" data-title="Karl Popper" data-language-autonym="Íslenska" data-language-local-name="Icelandic" class="interlanguage-link-target"><span>Íslenska</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Italian" lang="it" hreflang="it" data-title="Karl Popper" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%A7%D7%A8%D7%9C_%D7%A4%D7%95%D7%A4%D7%A8" title="קרל פופר – Hebrew" lang="he" hreflang="he" data-title="קרל פופר" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-jv mw-list-item"><a href="https://jv.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Javanese" lang="jv" hreflang="jv" data-title="Karl Popper" data-language-autonym="Jawa" data-language-local-name="Javanese" class="interlanguage-link-target"><span>Jawa</span></a></li><li class="interlanguage-link interwiki-kn mw-list-item"><a href="https://kn.wikipedia.org/wiki/%E0%B2%B8%E0%B2%B0%E0%B3%8D_%E0%B2%95%E0%B2%B0%E0%B3%8D%E0%B2%B2%E0%B3%8D_%E0%B2%AA%E0%B3%8A%E0%B2%AA%E0%B3%8D%E0%B2%AA%E0%B3%86%E0%B2%B0%E0%B3%8D" title="ಸರ್ ಕರ್ಲ್ ಪೊಪ್ಪೆರ್ – Kannada" lang="kn" hreflang="kn" data-title="ಸರ್ ಕರ್ಲ್ ಪೊಪ್ಪೆರ್" data-language-autonym="ಕನ್ನಡ" data-language-local-name="Kannada" class="interlanguage-link-target"><span>ಕನ್ನಡ</span></a></li><li class="interlanguage-link interwiki-ka mw-list-item"><a href="https://ka.wikipedia.org/wiki/%E1%83%99%E1%83%90%E1%83%A0%E1%83%9A_%E1%83%9E%E1%83%9D%E1%83%9E%E1%83%94%E1%83%A0%E1%83%98" title="კარლ პოპერი – Georgian" lang="ka" hreflang="ka" data-title="კარლ პოპერი" data-language-autonym="ქართული" data-language-local-name="Georgian" class="interlanguage-link-target"><span>ქართული</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%9A%D0%B0%D1%80%D0%BB_%D0%9F%D0%BE%D0%BF%D0%BF%D0%B5%D1%80" title="Карл Поппер – Kazakh" lang="kk" hreflang="kk" data-title="Карл Поппер" data-language-autonym="Қазақша" data-language-local-name="Kazakh" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-kw mw-list-item"><a href="https://kw.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Cornish" lang="kw" hreflang="kw" data-title="Karl Popper" data-language-autonym="Kernowek" data-language-local-name="Cornish" class="interlanguage-link-target"><span>Kernowek</span></a></li><li class="interlanguage-link interwiki-la mw-list-item"><a href="https://la.wikipedia.org/wiki/Carolus_Popper" title="Carolus Popper – Latin" lang="la" hreflang="la" data-title="Carolus Popper" data-language-autonym="Latina" data-language-local-name="Latin" class="interlanguage-link-target"><span>Latina</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/K%C4%81rlis_Popers" title="Kārlis Popers – Latvian" lang="lv" hreflang="lv" data-title="Kārlis Popers" data-language-autonym="Latviešu" data-language-local-name="Latvian" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Lithuanian" lang="lt" hreflang="lt" data-title="Karl Popper" data-language-autonym="Lietuvių" data-language-local-name="Lithuanian" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-li mw-list-item"><a href="https://li.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Limburgish" lang="li" hreflang="li" data-title="Karl Popper" data-language-autonym="Limburgs" data-language-local-name="Limburgish" class="interlanguage-link-target"><span>Limburgs</span></a></li><li class="interlanguage-link interwiki-lfn mw-list-item"><a href="https://lfn.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Lingua Franca Nova" lang="lfn" hreflang="lfn" data-title="Karl Popper" data-language-autonym="Lingua Franca Nova" data-language-local-name="Lingua Franca Nova" class="interlanguage-link-target"><span>Lingua Franca Nova</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Hungarian" lang="hu" hreflang="hu" data-title="Karl Popper" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%9A%D0%B0%D1%80%D0%BB_%D0%9F%D0%BE%D0%BF%D0%B5%D1%80" title="Карл Попер – Macedonian" lang="mk" hreflang="mk" data-title="Карл Попер" data-language-autonym="Македонски" data-language-local-name="Macedonian" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-mg mw-list-item"><a href="https://mg.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Malagasy" lang="mg" hreflang="mg" data-title="Karl Popper" data-language-autonym="Malagasy" data-language-local-name="Malagasy" class="interlanguage-link-target"><span>Malagasy</span></a></li><li class="interlanguage-link interwiki-ml mw-list-item"><a href="https://ml.wikipedia.org/wiki/%E0%B4%95%E0%B4%BE%E0%B5%BE_%E0%B4%AA%E0%B5%8B%E0%B4%AA%E0%B5%8D%E0%B4%AA%E0%B5%BC" title="കാൾ പോപ്പർ – Malayalam" lang="ml" hreflang="ml" data-title="കാൾ പോപ്പർ" data-language-autonym="മലയാളം" data-language-local-name="Malayalam" class="interlanguage-link-target"><span>മലയാളം</span></a></li><li class="interlanguage-link interwiki-xmf mw-list-item"><a href="https://xmf.wikipedia.org/wiki/%E1%83%99%E1%83%90%E1%83%A0%E1%83%9A_%E1%83%9E%E1%83%9D%E1%83%9E%E1%83%94%E1%83%A0%E1%83%98" title="კარლ პოპერი – Mingrelian" lang="xmf" hreflang="xmf" data-title="კარლ პოპერი" data-language-autonym="მარგალური" data-language-local-name="Mingrelian" class="interlanguage-link-target"><span>მარგალური</span></a></li><li class="interlanguage-link interwiki-arz mw-list-item"><a href="https://arz.wikipedia.org/wiki/%D9%83%D8%A7%D8%B1%D9%84_%D8%A8%D9%88%D8%A8%D8%B1" title="كارل بوبر – Egyptian Arabic" lang="arz" hreflang="arz" data-title="كارل بوبر" data-language-autonym="مصرى" data-language-local-name="Egyptian Arabic" class="interlanguage-link-target"><span>مصرى</span></a></li><li class="interlanguage-link interwiki-mzn mw-list-item"><a href="https://mzn.wikipedia.org/wiki/%D9%BE%D9%88%D9%BE%D8%B1" title="پوپر – Mazanderani" lang="mzn" hreflang="mzn" data-title="پوپر" data-language-autonym="مازِرونی" data-language-local-name="Mazanderani" class="interlanguage-link-target"><span>مازِرونی</span></a></li><li class="interlanguage-link interwiki-mn mw-list-item"><a href="https://mn.wikipedia.org/wiki/%D0%9A%D0%B0%D1%80%D0%BB_%D0%9F%D0%BE%D0%BF%D0%BF%D0%B5%D1%80" title="Карл Поппер – Mongolian" lang="mn" hreflang="mn" data-title="Карл Поппер" data-language-autonym="Монгол" data-language-local-name="Mongolian" class="interlanguage-link-target"><span>Монгол</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Dutch" lang="nl" hreflang="nl" data-title="Karl Popper" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E3%82%AB%E3%83%BC%E3%83%AB%E3%83%BB%E3%83%9D%E3%83%91%E3%83%BC" title="カール・ポパー – Japanese" lang="ja" hreflang="ja" data-title="カール・ポパー" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Karl Popper" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Norwegian Nynorsk" lang="nn" hreflang="nn" data-title="Karl Popper" data-language-autonym="Norsk nynorsk" data-language-local-name="Norwegian Nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-oc mw-list-item"><a href="https://oc.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Occitan" lang="oc" hreflang="oc" data-title="Karl Popper" data-language-autonym="Occitan" data-language-local-name="Occitan" class="interlanguage-link-target"><span>Occitan</span></a></li><li class="interlanguage-link interwiki-pa mw-list-item"><a href="https://pa.wikipedia.org/wiki/%E0%A8%95%E0%A8%BE%E0%A8%B0%E0%A8%B2_%E0%A8%AA%E0%A9%8C%E0%A8%AA%E0%A8%B0" title="ਕਾਰਲ ਪੌਪਰ – Punjabi" lang="pa" hreflang="pa" data-title="ਕਾਰਲ ਪੌਪਰ" data-language-autonym="ਪੰਜਾਬੀ" data-language-local-name="Punjabi" class="interlanguage-link-target"><span>ਪੰਜਾਬੀ</span></a></li><li class="interlanguage-link interwiki-ps mw-list-item"><a href="https://ps.wikipedia.org/wiki/%DA%A9%D8%A7%D8%B1%D9%84_%D9%BE%D8%A7%D9%BE%D8%B1" title="کارل پاپر – Pashto" lang="ps" hreflang="ps" data-title="کارل پاپر" data-language-autonym="پښتو" data-language-local-name="Pashto" class="interlanguage-link-target"><span>پښتو</span></a></li><li class="interlanguage-link interwiki-pms mw-list-item"><a href="https://pms.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Piedmontese" lang="pms" hreflang="pms" data-title="Karl Popper" data-language-autonym="Piemontèis" data-language-local-name="Piedmontese" class="interlanguage-link-target"><span>Piemontèis</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Polish" lang="pl" hreflang="pl" data-title="Karl Popper" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Portuguese" lang="pt" hreflang="pt" data-title="Karl Popper" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Romanian" lang="ro" hreflang="ro" data-title="Karl Popper" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%9F%D0%BE%D0%BF%D0%BF%D0%B5%D1%80,_%D0%9A%D0%B0%D1%80%D0%BB" title="Поппер, Карл – Russian" lang="ru" hreflang="ru" data-title="Поппер, Карл" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sco mw-list-item"><a href="https://sco.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Scots" lang="sco" hreflang="sco" data-title="Karl Popper" data-language-autonym="Scots" data-language-local-name="Scots" class="interlanguage-link-target"><span>Scots</span></a></li><li class="interlanguage-link interwiki-sq mw-list-item"><a href="https://sq.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Albanian" lang="sq" hreflang="sq" data-title="Karl Popper" data-language-autonym="Shqip" data-language-local-name="Albanian" class="interlanguage-link-target"><span>Shqip</span></a></li><li class="interlanguage-link interwiki-scn mw-list-item"><a href="https://scn.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Sicilian" lang="scn" hreflang="scn" data-title="Karl Popper" data-language-autonym="Sicilianu" data-language-local-name="Sicilian" class="interlanguage-link-target"><span>Sicilianu</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Karl_Raimund_Popper" title="Karl Raimund Popper – Slovak" lang="sk" hreflang="sk" data-title="Karl Raimund Popper" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Slovenian" lang="sl" hreflang="sl" data-title="Karl Popper" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%DA%A9%D8%A7%D8%B1%DA%B5_%D9%BE%DB%86%D9%BE%DB%95%D8%B1" title="کارڵ پۆپەر – Central Kurdish" lang="ckb" hreflang="ckb" data-title="کارڵ پۆپەر" data-language-autonym="کوردی" data-language-local-name="Central Kurdish" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%9A%D0%B0%D1%80%D0%BB_%D0%9F%D0%BE%D0%BF%D0%B5%D1%80" title="Карл Попер – Serbian" lang="sr" hreflang="sr" data-title="Карл Попер" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Serbo-Croatian" lang="sh" hreflang="sh" data-title="Karl Popper" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="Serbo-Croatian" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Finnish" lang="fi" hreflang="fi" data-title="Karl Popper" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Swedish" lang="sv" hreflang="sv" data-title="Karl Popper" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-tl mw-list-item"><a href="https://tl.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Tagalog" lang="tl" hreflang="tl" data-title="Karl Popper" data-language-autonym="Tagalog" data-language-local-name="Tagalog" class="interlanguage-link-target"><span>Tagalog</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%95%E0%AE%BE%E0%AE%B0%E0%AF%8D%E0%AE%B2%E0%AF%8D_%E0%AE%AA%E0%AF%8A%E0%AE%AA%E0%AF%8D%E0%AE%AA%E0%AE%B0%E0%AF%8D" title="கார்ல் பொப்பர் – Tamil" lang="ta" hreflang="ta" data-title="கார்ல் பொப்பர்" data-language-autonym="தமிழ்" data-language-local-name="Tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-tt badge-Q17437796 badge-featuredarticle mw-list-item" title="featured article badge"><a href="https://tt.wikipedia.org/wiki/Karl_Raimund_Popper" title="Karl Raimund Popper – Tatar" lang="tt" hreflang="tt" data-title="Karl Raimund Popper" data-language-autonym="Татарча / tatarça" data-language-local-name="Tatar" class="interlanguage-link-target"><span>Татарча / tatarça</span></a></li><li class="interlanguage-link interwiki-te mw-list-item"><a href="https://te.wikipedia.org/wiki/%E0%B0%95%E0%B0%BE%E0%B0%B0%E0%B1%8D%E0%B0%B2%E0%B1%8D_%E0%B0%B0%E0%B1%88%E0%B0%AE%E0%B0%82%E0%B0%A1%E0%B1%8D_%E0%B0%AA%E0%B0%BE%E0%B0%AA%E0%B0%B0%E0%B1%8D" title="కార్ల్ రైమండ్ పాపర్ – Telugu" lang="te" hreflang="te" data-title="కార్ల్ రైమండ్ పాపర్" data-language-autonym="తెలుగు" data-language-local-name="Telugu" class="interlanguage-link-target"><span>తెలుగు</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Turkish" lang="tr" hreflang="tr" data-title="Karl Popper" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%9A%D0%B0%D1%80%D0%BB_%D0%9F%D0%BE%D0%BF%D0%BF%D0%B5%D1%80" title="Карл Поппер – Ukrainian" lang="uk" hreflang="uk" data-title="Карл Поппер" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Vietnamese" lang="vi" hreflang="vi" data-title="Karl Popper" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-war mw-list-item"><a href="https://war.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Waray" lang="war" hreflang="war" data-title="Karl Popper" data-language-autonym="Winaray" data-language-local-name="Waray" class="interlanguage-link-target"><span>Winaray</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%E5%8D%A1%E5%B0%94%C2%B7%E6%B3%A2%E6%99%AE%E5%B0%94" title="卡尔·波普尔 – Wu" lang="wuu" hreflang="wuu" data-title="卡尔·波普尔" data-language-autonym="吴语" data-language-local-name="Wu" class="interlanguage-link-target"><span>吴语</span></a></li><li class="interlanguage-link interwiki-yi mw-list-item"><a href="https://yi.wikipedia.org/wiki/%D7%A7%D7%90%D7%A8%D7%9C_%D7%A4%D7%90%D7%A4%D7%A2%D7%A8" title="קארל פאפער – Yiddish" lang="yi" hreflang="yi" data-title="קארל פאפער" data-language-autonym="ייִדיש" data-language-local-name="Yiddish" class="interlanguage-link-target"><span>ייִדיש</span></a></li><li class="interlanguage-link interwiki-yo mw-list-item"><a href="https://yo.wikipedia.org/wiki/Karl_Popper" title="Karl Popper – Yoruba" lang="yo" hreflang="yo" data-title="Karl Popper" data-language-autonym="Yorùbá" data-language-local-name="Yoruba" class="interlanguage-link-target"><span>Yorùbá</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%E5%8D%A1%E7%88%BE%E6%B3%A2%E6%99%AE%E7%88%BE" title="卡爾波普爾 – Cantonese" lang="yue" hreflang="yue" data-title="卡爾波普爾" data-language-autonym="粵語" data-language-local-name="Cantonese" class="interlanguage-link-target"><span>粵語</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E5%8D%A1%E5%B0%94%C2%B7%E6%B3%A2%E6%99%AE%E5%B0%94" title="卡尔·波普尔 – Chinese" lang="zh" hreflang="zh" data-title="卡尔·波普尔" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q81244#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Change links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Karl_Popper" title="View the content page [c]" accesskey="c"><span>Page</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Talk:Karl_Popper" rel="discussion" title="Discussion about the content page [t]" accesskey="t"><span>Talk</span></a></li> </ul> </div> </div> <div id="vector-variants-dropdown" class="vector-dropdown emptyPortlet" > <input type="checkbox" id="vector-variants-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-variants-dropdown" class="vector-dropdown-checkbox " aria-label="Change language variant" > <label id="vector-variants-dropdown-label" for="vector-variants-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">English</span> </label> <div class="vector-dropdown-content"> <div id="p-variants" class="vector-menu mw-portlet mw-portlet-variants emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> </div> </div> </nav> </div> <div id="right-navigation" class="vector-collapsible"> <nav aria-label="Views"> <div id="p-views" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-views" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-view" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Karl_Popper"><span>Read</span></a></li><li id="ca-ve-edit" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Karl_Popper&veaction=edit" title="Edit this page [v]" accesskey="v"><span>Change</span></a></li><li id="ca-edit" class="collapsible vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Karl_Popper&action=edit" title="Edit the source code of this page [e]" accesskey="e"><span>Change source</span></a></li><li id="ca-history" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Karl_Popper&action=history" title="Past revisions of this page [h]" accesskey="h"><span>View history</span></a></li> </ul> </div> </div> </nav> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-dropdown" class="vector-dropdown vector-page-tools-dropdown" > <input type="checkbox" id="vector-page-tools-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-tools-dropdown" class="vector-dropdown-checkbox " aria-label="Tools" > <label id="vector-page-tools-dropdown-label" for="vector-page-tools-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">Tools</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-tools-unpinned-container" class="vector-unpinned-container"> <div id="vector-page-tools" class="vector-page-tools vector-pinnable-element"> <div class="vector-pinnable-header vector-page-tools-pinnable-header vector-pinnable-header-unpinned" data-feature-name="page-tools-pinned" data-pinnable-element-id="vector-page-tools" data-pinned-container-id="vector-page-tools-pinned-container" data-unpinned-container-id="vector-page-tools-unpinned-container" > <div class="vector-pinnable-header-label">Tools</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-page-tools.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-page-tools.unpin">hide</button> </div> <div id="p-cactions" class="vector-menu mw-portlet mw-portlet-cactions emptyPortlet vector-has-collapsible-items" title="More options" > <div class="vector-menu-heading"> Actions </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-more-view" class="selected vector-more-collapsible-item mw-list-item"><a href="/wiki/Karl_Popper"><span>Read</span></a></li><li id="ca-more-ve-edit" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Karl_Popper&veaction=edit" title="Edit this page [v]" accesskey="v"><span>Change</span></a></li><li id="ca-more-edit" class="collapsible vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Karl_Popper&action=edit" title="Edit the source code of this page [e]" accesskey="e"><span>Change source</span></a></li><li id="ca-more-history" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Karl_Popper&action=history"><span>View history</span></a></li> </ul> </div> </div> <div id="p-tb" class="vector-menu mw-portlet mw-portlet-tb" > <div class="vector-menu-heading"> General </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-whatlinkshere" class="mw-list-item"><a href="/wiki/Special:WhatLinksHere/Karl_Popper" title="A list of all wiki pages that link here [j]" accesskey="j"><span>What links here</span></a></li><li id="t-recentchangeslinked" class="mw-list-item"><a href="/wiki/Special:RecentChangesLinked/Karl_Popper" rel="nofollow" title="New changes in pages linked from this page [k]" accesskey="k"><span>Related changes</span></a></li><li id="t-upload" class="mw-list-item"><a href="//commons.wikimedia.org/wiki/Special:UploadWizard" title="Upload files [u]" accesskey="u"><span>Upload file</span></a></li><li id="t-permalink" class="mw-list-item"><a href="/w/index.php?title=Karl_Popper&oldid=9598536" title="Permanent link to this revision of this page"><span>Permanent link</span></a></li><li id="t-info" class="mw-list-item"><a href="/w/index.php?title=Karl_Popper&action=info" title="More information about this page"><span>Page information</span></a></li><li id="t-cite" class="mw-list-item"><a href="/w/index.php?title=Special:CiteThisPage&page=Karl_Popper&id=9598536&wpFormIdentifier=titleform" title="Information on how to cite this page"><span>Cite this page</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=Special:UrlShortener&url=https%3A%2F%2Fsimple.wikipedia.org%2Fwiki%2FKarl_Popper"><span>Get shortened URL</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Special:QrCode&url=https%3A%2F%2Fsimple.wikipedia.org%2Fwiki%2FKarl_Popper"><span>Download QR code</span></a></li> </ul> </div> </div> <div id="p-coll-print_export" class="vector-menu mw-portlet mw-portlet-coll-print_export" > <div class="vector-menu-heading"> Print/export </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="coll-create_a_book" class="mw-list-item"><a href="/w/index.php?title=Special:Book&bookcmd=book_creator&referer=Karl+Popper"><span>Make a book</span></a></li><li id="coll-download-as-rl" class="mw-list-item"><a href="/w/index.php?title=Special:DownloadAsPdf&page=Karl_Popper&action=show-download-screen"><span>Download as PDF</span></a></li><li id="t-print" class="mw-list-item"><a href="/w/index.php?title=Karl_Popper&printable=yes" title="Printable version of this page [p]" accesskey="p"><span>Page for printing</span></a></li> </ul> </div> </div> <div id="p-wikibase-otherprojects" class="vector-menu mw-portlet mw-portlet-wikibase-otherprojects" > <div class="vector-menu-heading"> In other projects </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="wb-otherproject-link wb-otherproject-commons mw-list-item"><a href="https://commons.wikimedia.org/wiki/Category:Karl_Popper" hreflang="en"><span>Wikimedia Commons</span></a></li><li id="t-wikibase" class="wb-otherproject-link wb-otherproject-wikibase-dataitem mw-list-item"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q81244" title="Link to connected data repository item [g]" accesskey="g"><span>Wikidata item</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> </div> </div> </div> <div class="vector-column-end"> <div class="vector-sticky-pinned-container"> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Appearance</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">hide</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Simple English Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><style data-mw-deduplicate="TemplateStyles:r10098372">.mw-parser-output .infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox biography vcard"><tbody><tr><th colspan="2" class="infobox-above" style="font-size:125%;"><div class="fn">Karl Raimond Popper</div></th></tr><tr><td colspan="2" class="infobox-image"><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:Karl_Popper.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/4/43/Karl_Popper.jpg/220px-Karl_Popper.jpg" decoding="async" width="220" height="282" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/43/Karl_Popper.jpg/330px-Karl_Popper.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/43/Karl_Popper.jpg/440px-Karl_Popper.jpg 2x" data-file-width="600" data-file-height="769" /></a></span><div class="infobox-caption">Sir Karl Popper c. 1980s</div></td></tr><tr><th scope="row" class="infobox-label">Born</th><td class="infobox-data">28 July 1902<br /><a href="/wiki/Vienna" title="Vienna">Vienna</a>, <a href="/wiki/Austria" title="Austria">Austria</a></td></tr><tr><th scope="row" class="infobox-label">Died</th><td class="infobox-data">17 September 1994<span style="display:none">(1994-09-17)</span> (aged 92)<br /><a href="/wiki/London" title="London">London</a>, <a href="/wiki/England" title="England">England</a></td></tr><tr><td colspan="2" class="infobox-full-data"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r10098372"></td></tr><tr><th scope="row" class="infobox-label">Era</th><td class="infobox-data category">20th century philosophy</td></tr><tr><th scope="row" class="infobox-label">Region</th><td class="infobox-data category"><a href="/w/index.php?title=Western_Philosophy&action=edit&redlink=1" class="new" title="Western Philosophy (not yet started)">Western Philosophy</a></td></tr><tr class="note"><th scope="row" class="infobox-label"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Main interests</div></th><td class="infobox-data"><a href="/wiki/Epistemology" title="Epistemology">Epistemology</a><br /><a href="/wiki/Philosophy_of_science" title="Philosophy of science">Philosophy of science</a><br /><a href="/wiki/Social_philosophy" title="Social philosophy">Social</a> and <a href="/wiki/Political_philosophy" title="Political philosophy">political philosophy</a></td></tr><tr><th scope="row" class="infobox-label"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Notable ideas</div></th><td class="infobox-data"><a href="/wiki/Falsifiability" title="Falsifiability">Falsifiability</a> <a href="/w/index.php?title=Hypothetico-deductive_method&action=edit&redlink=1" class="new" title="Hypothetico-deductive method (not yet started)">Hypothetico-deductive method</a><br /><a href="/wiki/Open_society" title="Open society">Open society</a></td></tr><tr class="note"><td colspan="2" class="infobox-full-data"><div class="mw-collapsible mw-collapsed" style="text-align: center; font-size: 95%;"> <div style="line-height: 1.6em; font-weight: bold; font-size: 100%; text-align: left;"><div>Influences</div></div> <ul class="mw-collapsible-content" style="font-size: 105%; margin-top: 0; margin-bottom: 0; line-height: inherit; text-align: left; list-style: none none; margin-left: 0;"><li style="line-height: inherit; margin: 0"><div class="center" style="width:auto; margin-left:auto; margin-right:auto;"><a href="/wiki/Socrates" title="Socrates">Socrates</a> <small>(via <a href="/wiki/Plato" title="Plato">Plato</a>)</small> <b>·</b>  <a href="/wiki/Aristotle" title="Aristotle">Aristotle</a><br /><a href="/wiki/Immanuel_Kant" title="Immanuel Kant">Kant</a> <b>·</b>  <a href="/wiki/Arthur_Schopenhauer" title="Arthur Schopenhauer">Schopenhauer</a> <b>·</b>  <a href="/wiki/Georg_Wilhelm_Friedrich_Hegel" title="Georg Wilhelm Friedrich Hegel">Hegel</a><br /><a href="/wiki/Albert_Einstein" title="Albert Einstein">Einstein</a> <b>·</b>  <a href="/wiki/S%C3%B8ren_Kierkegaard" title="Søren Kierkegaard">Kierkegaard</a> <b>·</b>  <a href="/wiki/Ludwig_Wittgenstein" title="Ludwig Wittgenstein">Wittgenstein</a><br /><a href="/wiki/Vienna_Circle" title="Vienna Circle">Vienna Circle</a> <b>·</b>  <a href="/w/index.php?title=Alfred_Tarski&action=edit&redlink=1" class="new" title="Alfred Tarski (not yet started)">Tarski</a> <b>·</b>  <a href="/w/index.php?title=Otto_Selz&action=edit&redlink=1" class="new" title="Otto Selz (not yet started)">Selz</a><br /><a href="/wiki/Bertrand_Russell" title="Bertrand Russell">Russell</a> <b>·</b>  <a href="/w/index.php?title=Donald_T._Campbell&action=edit&redlink=1" class="new" title="Donald T. Campbell (not yet started)">Campbell</a> <b>·</b>  <a href="/wiki/Edmund_Burke" title="Edmund Burke">Burke</a></div></li></ul> </div></td></tr><tr class="note"><td colspan="2" class="infobox-full-data"><div class="mw-collapsible mw-collapsed" style="text-align: center; font-size: 95%;"> <div style="line-height: 1.6em; font-weight: bold; font-size: 100%; text-align: left;"><div>Influenced</div></div> <ul class="mw-collapsible-content" style="font-size: 105%; margin-top: 0; margin-bottom: 0; line-height: inherit; text-align: left; list-style: none none; margin-left: 0;"><li style="line-height: inherit; margin: 0"><div class="center" style="width:auto; margin-left:auto; margin-right:auto;">Virtually all <a href="/wiki/Philosophy_of_science" title="Philosophy of science">philosophy of science</a> since 1930s <b>·</b>  <a href="/wiki/Friedrich_Hayek" title="Friedrich Hayek">Hayek</a> <b>·</b>  <a href="/wiki/Milton_Friedman" title="Milton Friedman">Friedman</a><br /><a href="/w/index.php?title=Imre_Lakatos&action=edit&redlink=1" class="new" title="Imre Lakatos (not yet started)">Lakatos</a> <b>·</b>  <a href="/w/index.php?title=Paul_Feyerabend&action=edit&redlink=1" class="new" title="Paul Feyerabend (not yet started)">Feyerabend</a> <b>·</b>  <a href="/wiki/George_Soros" title="George Soros">Soros</a><br /><a href="/w/index.php?title=David_Miller_(philosopher)&action=edit&redlink=1" class="new" title="David Miller (philosopher) (not yet started)">Miller</a> <b>·</b>  <a href="/w/index.php?title=Joseph_Agassi&action=edit&redlink=1" class="new" title="Joseph Agassi (not yet started)">Agassi</a> <b>·</b>  <a href="/w/index.php?title=William_Warren_Bartley&action=edit&redlink=1" class="new" title="William Warren Bartley (not yet started)">Bartley</a> <b>·</b>  <a href="/w/index.php?title=Ernst_Gombrich&action=edit&redlink=1" class="new" title="Ernst Gombrich (not yet started)">Gombrich</a><br /><a href="/w/index.php?title=Ian_Jarvie&action=edit&redlink=1" class="new" title="Ian Jarvie (not yet started)">Jarvie</a> <b>·</b>  <a href="/w/index.php?title=Paul_Levinson&action=edit&redlink=1" class="new" title="Paul Levinson (not yet started)">Levinson</a> <b>·</b>  <a href="/wiki/Helmut_Schmidt" title="Helmut Schmidt">Schmidt</a> <b>·</b>  <a href="/w/index.php?title=Peter_Munz&action=edit&redlink=1" class="new" title="Peter Munz (not yet started)">Munz</a><br /><a href="/w/index.php?title=Bryan_Magee&action=edit&redlink=1" class="new" title="Bryan Magee (not yet started)">Magee</a> <b>·</b>  <a href="/wiki/Konrad_Lorenz" title="Konrad Lorenz">Lorenz</a> <b>·</b>  <a href="/w/index.php?title=Jeremy_Shearmur&action=edit&redlink=1" class="new" title="Jeremy Shearmur (not yet started)">Shearmur</a><br /><a href="/wiki/Peter_Medawar" title="Peter Medawar">Medawar</a> <b>·</b>  <a href="/w/index.php?title=Dimitris_Dimitrakos&action=edit&redlink=1" class="new" title="Dimitris Dimitrakos (not yet started)">Dimitrakos</a> <b>·</b>  <a href="/wiki/Hans_Albert" title="Hans Albert">Albert</a> <b>·</b>  <a href="/w/index.php?title=Ernest_Gellner&action=edit&redlink=1" class="new" title="Ernest Gellner (not yet started)">Gellner</a> <b>·</b>  <a href="/w/index.php?title=Abdolkarim_Soroush&action=edit&redlink=1" class="new" title="Abdolkarim Soroush (not yet started)">Soroush</a></div></li></ul> </div></td></tr><tr style="display:none"><td colspan="2"> </td></tr></tbody></table> <p><a href="/wiki/Knight_Bachelor" title="Knight Bachelor">Sir</a> <b>Karl Popper</b> <a href="/wiki/Order_of_the_Companions_of_Honour" title="Order of the Companions of Honour">CH</a> <a href="/wiki/Fellow_of_the_Royal_Society" class="mw-redirect" title="Fellow of the Royal Society">FRS</a> <a href="/wiki/Fellow_of_the_British_Academy" title="Fellow of the British Academy">FBA</a> (28 July 1902 – 17 September 1994) was an <a href="/wiki/Austria" title="Austria">Austrian</a> and <a href="/wiki/United_Kingdom" title="United Kingdom">British</a><sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Philosopher" class="mw-redirect" title="Philosopher">philosopher</a> and a professor at the <a href="/wiki/London_School_of_Economics" title="London School of Economics">London School of Economics</a>. </p><p>He is considered one of the most influential <a href="/wiki/Philosophy_of_science" title="Philosophy of science">philosophers of science</a> of the <a href="/wiki/20th_century" title="20th century">20th century</a>. He also wrote on social and political philosophy, especially the evils of <a href="/wiki/Totalitarian" class="mw-redirect" title="Totalitarian">totalitarian</a> ideas and politics. Popper is known for the idea of <a href="/wiki/Empiricism" title="Empiricism">empirical</a> <a href="/wiki/Falsification" class="mw-redirect" title="Falsification">falsification</a>. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Life">Life</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Karl_Popper&veaction=edit&section=1" title="Change section: Life" class="mw-editsection-visualeditor"><span>change</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Karl_Popper&action=edit&section=1" title="Edit section's source code: Life"><span>change source</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Karl Popper was born in <a href="/wiki/Vienna" title="Vienna">Vienna</a> (then in <a href="/wiki/Austria-Hungary" title="Austria-Hungary">Austria-Hungary</a>) in 1902 to <a href="/wiki/Middle_class" title="Middle class">middle-class</a> parents of <a href="/wiki/Jew" title="Jew">Jewish</a> origins, both of whom had converted to <a href="/wiki/Christianity" title="Christianity">Christianity</a>.<sup id="cite_ref-MageeStoryPhilosophy_2-0" class="reference"><a href="#cite_note-MageeStoryPhilosophy-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> Popper received a <a href="/wiki/Lutheran" class="mw-redirect" title="Lutheran">Lutheran</a> upbringing and was educated at the <a href="/wiki/University_of_Vienna" title="University of Vienna">University of Vienna</a>.<sup id="cite_ref-MageeStoryPhilosophy_2-1" class="reference"><a href="#cite_note-MageeStoryPhilosophy-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> His father had 12,000–14,000 volumes in his personal library.<sup id="cite_ref-bibliophile_3-0" class="reference"><a href="#cite_note-bibliophile-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p><p>In 1919, he became attracted to <a href="/wiki/Marxism" title="Marxism">Marxism</a>. He joined the Association of Socialist School Students and also became a member of the <a href="/wiki/Social_Democratic_Party_of_Austria" title="Social Democratic Party of Austria">Social Democratic Party of Austria</a>, which was at that time a party that fully adopted the Marxist ideology.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> He soon stopped believing in Marxism, and was a supporter of <a href="/wiki/Social_liberalism" title="Social liberalism">social liberalism</a> for the rest of his life. </p> <div class="mw-heading mw-heading2"><h2 id="Falsification">Falsification</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Karl_Popper&veaction=edit&section=2" title="Change section: Falsification" class="mw-editsection-visualeditor"><span>change</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Karl_Popper&action=edit&section=2" title="Edit section's source code: Falsification"><span>change source</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Popper, brought up in Vienna, was well aware of the <a href="/wiki/Vienna_Circle" title="Vienna Circle">Vienna Circle</a>. That school of <a href="/wiki/Logical_positivism" class="mw-redirect" title="Logical positivism">logical positivism</a>, led by <a href="/w/index.php?title=Moritz_Schlick&action=edit&redlink=1" class="new" title="Moritz Schlick (not yet started)">Moritz Schlick</a>,<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> defined <a href="/wiki/Knowledge" title="Knowledge">knowledge</a> (especially scientific knowledge) as being <a href="/wiki/Proposition" title="Proposition">propositions</a> which could be verified.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Popper thought this was quite wrong. In his opinion, science grew indirectly, by wrong ideas being <i>falsified</i>. This he worked up in great detail in a series of books, of which <i>The logic of scientific discovery</i> is the most famous. All philosophy of science since then has had to deal with this issue, the <i>criterion</i>. By 'criterion' is meant: what is it that makes a theory truly scientific, as opposed to simply <a href="/wiki/Common_sense" title="Common sense">common sense</a> or <a href="/wiki/Opinion" title="Opinion">opinion</a>? </p> <div class="mw-heading mw-heading2"><h2 id="The_open_society">The open society</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Karl_Popper&veaction=edit&section=3" title="Change section: The open society" class="mw-editsection-visualeditor"><span>change</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Karl_Popper&action=edit&section=3" title="Edit section's source code: The open society"><span>change source</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Popper's work on political philosophy is also of great importance. <a href="/wiki/Marx" class="mw-redirect" title="Marx">Marx</a> claimed knowledge of an historical process, where societies evolved from one state to another, until they reached a final state. This type of thought is known as 'historicism'. Popper argued that the growth of human knowledge partly causes the evolution of human history. Since "no society can predict its own future states of knowledge", it follows that no science can predict human history. </p><p>Popper's great works in defence of the liberal society were <i>The open society and its enemies</i> and <i>The poverty of historicism</i>. His allies in this struggle were <a href="/wiki/Friedrich_Hayek" title="Friedrich Hayek">Friedrich Hayek</a>, <a href="/wiki/Ludwig_von_Mises" title="Ludwig von Mises">Ludwig von Mises</a> and <a href="/wiki/Milton_Friedman" title="Milton Friedman">Milton Friedman</a>. </p> <div class="mw-heading mw-heading3"><h3 id="The_paradox_of_tolerance">The paradox of tolerance</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Karl_Popper&veaction=edit&section=4" title="Change section: The paradox of tolerance" class="mw-editsection-visualeditor"><span>change</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Karl_Popper&action=edit&section=4" title="Edit section's source code: The paradox of tolerance"><span>change source</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Although Popper was an advocate of <a href="/wiki/Toleration" title="Toleration">toleration</a>, he thought intolerance should not be tolerated. If tolerance allowed intolerance to succeed completely, tolerance itself would be threatened. In <i>The open society and its enemies: The spell of Plato</i>, he argued that: </p> <dl><dd>"Unlimited tolerance must lead to the disappearance of tolerance. If we extend unlimited tolerance even to those who are intolerant, if we are not prepared to defend a tolerant society against the onslaught of the intolerant, then the tolerant will be destroyed, and tolerance with them".</dd></dl> <div class="mw-heading mw-heading2"><h2 id="The_Three_worlds_doctrine">The Three worlds doctrine</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Karl_Popper&veaction=edit&section=5" title="Change section: The Three worlds doctrine" class="mw-editsection-visualeditor"><span>change</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Karl_Popper&action=edit&section=5" title="Edit section's source code: The Three worlds doctrine"><span>change source</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <b>Three Worlds Doctrine</b> was invented by Popper and is used in <a href="/wiki/Philosophy" title="Philosophy">philosophy</a> to understand the condition in which we find ourselves as <a href="/wiki/Human" title="Human">human beings</a>. </p><p>It assumes the existence of three worlds. They are </p> <ul><li>The outside world, which we know and understand with our <a href="/wiki/Sensory_system" title="Sensory system">senses</a>.</li></ul> <ul><li>The world of <a href="/wiki/Consciousness" title="Consciousness">consciousness</a>, which we experience as our inner <a href="/wiki/Thought" title="Thought">thoughts</a> and <a href="/wiki/Dream" title="Dream">dreams</a></li></ul> <ul><li>The world of thought content that is passed between humans in <a href="/wiki/Culture" title="Culture">culture</a> and <a href="/wiki/Speech" title="Speech">speech</a> yet exists outside of any individual person.</li></ul> <p>This way of looking at reality is used by many philosophers to explain the relationship between the physical and spiritual worlds. </p><p>It was first described by the Austrian-British philosopher Karl Popper in a <a href="/wiki/Lecture" title="Lecture">lecture</a> given in August 1967. </p> <div class="mw-heading mw-heading2"><h2 id="Key_works">Key works</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Karl_Popper&veaction=edit&section=6" title="Change section: Key works" class="mw-editsection-visualeditor"><span>change</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Karl_Popper&action=edit&section=6" title="Edit section's source code: Key works"><span>change source</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><i>The logic of scientific discovery</i>, 1934 (as <i>Logik der Forschung</i>, English translation 1959), <style data-mw-deduplicate="TemplateStyles:r9724332">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-415-27844-9" title="Special:BookSources/0-415-27844-9">0-415-27844-9</a></li> <li><i>The poverty of historicism</i>, 1936 (private reading at a meeting in Brussels, 1944/45 as a series of journal articles in <i>Econometrica</i>, 1957 as a book), <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r9724332"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-415-06569-0" title="Special:BookSources/0-415-06569-0">0-415-06569-0</a></li> <li><i>The open society and its enemies</i>, 1945 Vol 1 The spell of Plato. <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r9724332"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-415-29063-5" title="Special:BookSources/0-415-29063-5">0-415-29063-5</a>, Vol 2 The high tide of prophecy: Hegel, Marx, and the aftermath. <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r9724332"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-415-29063-5" title="Special:BookSources/0-415-29063-5">0-415-29063-5</a></li> <li><i>Conjectures and refutations: the growth of scientific knowledge</i>, 1963, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r9724332"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-415-04318-2" title="Special:BookSources/0-415-04318-2">0-415-04318-2</a></li> <li><i>Objective knowledge: an evolutionary approach</i>, 1972, Rev. ed., 1979, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r9724332"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-19-875024-2" title="Special:BookSources/0-19-875024-2">0-19-875024-2</a></li> <li><i>Unended quest; an intellectual autobiography</i>, 1976, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r9724332"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-415-28590-9" title="Special:BookSources/0-415-28590-9">0-415-28590-9</a></li> <li><i>After the Open Society</i>, 2008. Edited by Jeremy Shearmur and Piers Norris Turner, this volume contains a large number of Popper's previously unpublished or uncollected writings on political and social themes. <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r9724332"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-415-30908-0" title="Special:BookSources/978-0-415-30908-0">978-0-415-30908-0</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="Related_pages">Related pages</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Karl_Popper&veaction=edit&section=7" title="Change section: Related pages" class="mw-editsection-visualeditor"><span>change</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Karl_Popper&action=edit&section=7" title="Edit section's source code: Related pages"><span>change source</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Liberalism" title="Liberalism">Liberalism</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Karl_Popper&veaction=edit&section=8" title="Change section: References" class="mw-editsection-visualeditor"><span>change</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Karl_Popper&action=edit&section=8" title="Edit section's source code: References"><span>change source</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r9724317">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><a href="#cite_ref-1">↑</a></span> <span class="reference-text">Watkins, J. Obituary of Karl Popper, 1902-1994. <i>Proceedings of the British Academy</i>, <b>94</b>, pp. 645–684</span> </li> <li id="cite_note-MageeStoryPhilosophy-2"><span class="mw-cite-backlink">↑ <sup><a href="#cite_ref-MageeStoryPhilosophy_2-0">2.0</a></sup> <sup><a href="#cite_ref-MageeStoryPhilosophy_2-1">2.1</a></sup></span> <span class="reference-text">Magee, Bryan 2001. <i>The story of philosophy.</i> New York: DK Publishing. p221</span> </li> <li id="cite_note-bibliophile-3"><span class="mw-cite-backlink"><a href="#cite_ref-bibliophile_3-0">↑</a></span> <span class="reference-text">Raphael F. <i>The great philosophers</i> London: Phoenix. p447</span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><a href="#cite_ref-4">↑</a></span> <span class="reference-text"><a rel="nofollow" class="external free" href="http://plato.stanford.edu/entries/popper/">http://plato.stanford.edu/entries/popper/</a> - Stephen Thornton, The Stanford Encyclopedia of Philosophy</span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><a href="#cite_ref-5">↑</a></span> <span class="reference-text">Schlick, Moritz 1974. <i>General theory of knowledge</i>. Springer, Vienna and New York. (transl of the 2nd German edition of 1925).</span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><a href="#cite_ref-6">↑</a></span> <span class="reference-text">Ayer A.J. 1936 [2nd ed 1946] <i>Language, truth and logic</i>.</span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="Other_websites">Other websites</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Karl_Popper&veaction=edit&section=9" title="Change section: Other websites" class="mw-editsection-visualeditor"><span>change</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Karl_Popper&action=edit&section=9" title="Edit section's source code: Other websites"><span>change source</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r9671870">.mw-parser-output .side-box{margin:4px 0;box-sizing:border-box;border:1px solid #aaa;font-size:88%;line-height:1.25em;background-color:var(--background-color-interactive-subtle,#f8f9fa);display:flow-root}.mw-parser-output .side-box-abovebelow,.mw-parser-output .side-box-text{padding:0.25em 0.9em}.mw-parser-output .side-box-image{padding:2px 0 2px 0.9em;text-align:center}.mw-parser-output .side-box-imageright{padding:2px 0.9em 2px 0;text-align:center}@media(min-width:500px){.mw-parser-output .side-box-flex{display:flex;align-items:center}.mw-parser-output .side-box-text{flex:1;min-width:0}}@media(min-width:720px){.mw-parser-output .side-box{width:238px}.mw-parser-output .side-box-right{clear:right;float:right;margin-left:1em}.mw-parser-output .side-box-left{margin-right:1em}}</style><style data-mw-deduplicate="TemplateStyles:r9671876">@media print{body.ns-0 .mw-parser-output .sistersitebox{display:none!important}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-en-v2.svg"]{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-en-v2.svg"]{background-color:white}}</style><div class="side-box side-box-right plainlinks sistersitebox"><style data-mw-deduplicate="TemplateStyles:r8662964">.mw-parser-output .plainlist ol,.mw-parser-output .plainlist ul{line-height:inherit;list-style:none;margin:0;padding:0}.mw-parser-output .plainlist ol li,.mw-parser-output .plainlist ul li{margin-bottom:0}</style> <div class="side-box-flex"> <div class="side-box-image"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Wikiquote-logo.svg/34px-Wikiquote-logo.svg.png" decoding="async" width="34" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Wikiquote-logo.svg/51px-Wikiquote-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Wikiquote-logo.svg/68px-Wikiquote-logo.svg.png 2x" data-file-width="300" data-file-height="355" /></span></span></div> <div class="side-box-text plainlist">Wikiquote has a collection of quotations related to: <i><b><a href="https://en.wikipedia.org/wiki/q:Special:Search/Karl_Popper" class="extiw" title="en:q:Special:Search/Karl Popper">Karl Popper</a></b></i></div></div> </div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r9671870"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r9671876"><div class="side-box side-box-right plainlinks sistersitebox"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r8662964"> <div class="side-box-flex"> <div class="side-box-image"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/38px-Wikisource-logo.svg.png" decoding="async" width="38" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/57px-Wikisource-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/76px-Wikisource-logo.svg.png 2x" data-file-width="410" data-file-height="430" /></span></span></div> <div class="side-box-text plainlist"><a href="/wiki/Wikisource" title="Wikisource">Wikisource</a> has original writing related to this article: <div style="margin-left: 10px;"><b><a href="https://en.wikisource.org/wiki/Karl_Popper:_Prague_lecture,_1994" class="extiw" title="wikisource:Karl Popper: Prague lecture, 1994">Karl Popper: Prague lecture, 1994</a></b></div></div></div> </div> <ul><li><a rel="nofollow" class="external text" href="https://www.philosophytalk.org/pastShows/Popper.html">Discussion of Popper's Life and Work</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20080414230724/http://www.philosophytalk.org/pastShows/Popper.html">Archived</a> 2008-04-14 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a> from <a rel="nofollow" class="external text" href="https://www.philosophytalk.org">Philosophy Talk Radio Program</a></li> <li><a rel="nofollow" class="external text" href="http://plato.stanford.edu/entries/popper/">Karl Popper</a> from <a rel="nofollow" class="external text" href="http://plato.stanford.edu/">Stanford Encyclopedia of Philosophy</a></li> <li><a rel="nofollow" class="external text" href="http://www.eeng.dcu.ie/~tkpw/">The Karl Popper Web</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20071203041804/http://www.eeng.dcu.ie/~tkpw/">Archived</a> 2007-12-03 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a></li> <li><a rel="nofollow" class="external text" href="http://www.univie.ac.at/science-archives/popper/de/index.html">Karl Popper Institute</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20080311163937/http://www.univie.ac.at/science-archives/popper/de/index.html">Archived</a> 2008-03-11 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a> includes complete bibliography 1925-1999</li> <li><a rel="nofollow" class="external text" href="http://www.poppersociety.net/">Sir Karl Popper Society</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20150913041714/http://www.poppersociety.net/">Archived</a> 2015-09-13 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a> International Association for the Promotion of Science and Research, in German</li> <li><a rel="nofollow" class="external text" href="http://www.friesian.com/popper.htm">Influence on Friesian Philosophy</a></li> <li><a rel="nofollow" class="external text" href="http://www.soros.org/">Open Society Institute</a> George Soros foundations network</li> <li><a rel="nofollow" class="external text" href="https://people.math.gatech.edu/~ecroot/gardner_popper.pdf">"A Skeptical Look at Karl Popper"</a> by <a href="/wiki/Martin_Gardner" title="Martin Gardner">Martin Gardner</a></li> <li><a rel="nofollow" class="external text" href="http://www.la-articles.org.uk/popper.htm">"A Sceptical Look at 'A Skeptical Look at Karl Popper'"</a> by J C Lester.</li> <li><a rel="nofollow" class="external text" href="http://cla.calpoly.edu/~fotoole/321.1/popper.html">Sir Karl Popper: Science: Conjectures and Refutations</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20150213201422/http://cla.calpoly.edu/~fotoole/321.1/popper.html">Archived</a> 2015-02-13 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a></li> <li><a rel="nofollow" class="external text" href="http://www.johnkadvany.com/GettingStarted/Kadvany_Design/Assets/LakatosPage/Lakatos_Frameset_3.htm">Information on Lakatos/Popper</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20150214033705/http://johnkadvany.com/GettingStarted/Kadvany_Design/Assets/LakatosPage/Lakatos_Frameset_3.htm">Archived</a> 2015-02-14 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a> Site maintained by John Kadvany, PhD.</li> <li><a rel="nofollow" class="external text" href="http://www.utilitarian.net/singer/by/19740502.htm"><i>Discovering Karl Popper</i></a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160112142415/http://www.utilitarian.net/singer/by/19740502.htm">Archived</a> 2016-01-12 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a> by Peter Singer The New York Review of Books, vol. 21, no. 7 (May 2, 1974)</li> <li><a rel="nofollow" class="external text" href="http://www.philsci.com"><i>History of Twentieth-Century Philosophy of Science</i>, BOOK V: Karl Popper</a> Site offers free downloads by chapter available for public use.</li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r9122542">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist dd:last-child::after,.mw-parser-output .hlist dt:last-child::after,.mw-parser-output .hlist li:last-child::after{content:none}.mw-parser-output .hlist dd dd:first-child::before,.mw-parser-output .hlist dd dt:first-child::before,.mw-parser-output .hlist dd li:first-child::before,.mw-parser-output .hlist dt dd:first-child::before,.mw-parser-output .hlist dt dt:first-child::before,.mw-parser-output .hlist dt li:first-child::before,.mw-parser-output .hlist li dd:first-child::before,.mw-parser-output .hlist li dt:first-child::before,.mw-parser-output .hlist li li:first-child::before{content:" (";font-weight:normal}.mw-parser-output .hlist dd dd:last-child::after,.mw-parser-output .hlist dd dt:last-child::after,.mw-parser-output .hlist dd li:last-child::after,.mw-parser-output .hlist dt dd:last-child::after,.mw-parser-output .hlist dt dt:last-child::after,.mw-parser-output .hlist dt li:last-child::after,.mw-parser-output .hlist li dd:last-child::after,.mw-parser-output .hlist li dt:last-child::after,.mw-parser-output .hlist li li:last-child::after{content:")";font-weight:normal}.mw-parser-output .hlist ol{counter-reset:listitem}.mw-parser-output .hlist ol>li{counter-increment:listitem}.mw-parser-output .hlist ol>li::before{content:" "counter(listitem)"\a0 "}.mw-parser-output .hlist dd ol>li:first-child::before,.mw-parser-output .hlist dt ol>li:first-child::before,.mw-parser-output .hlist li ol>li:first-child::before{content:" ("counter(listitem)"\a0 "}</style><style data-mw-deduplicate="TemplateStyles:r10098651">.mw-parser-output .navbox{box-sizing:border-box;border:1px solid #a2a9b1;width:100%;clear:both;font-size:88%;text-align:center;padding:1px;margin:1em auto 0}.mw-parser-output .navbox .navbox{margin-top:0}.mw-parser-output .navbox+.navbox,.mw-parser-output .navbox+.navbox-styles+.navbox{margin-top:-1px}.mw-parser-output .navbox-inner,.mw-parser-output .navbox-subgroup{width:100%}.mw-parser-output .navbox-group,.mw-parser-output .navbox-title,.mw-parser-output .navbox-abovebelow{padding:0.25em 1em;line-height:1.5em;text-align:center}.mw-parser-output .navbox-group{white-space:nowrap;text-align:right}.mw-parser-output .navbox,.mw-parser-output .navbox-subgroup{background-color:#fdfdfd}.mw-parser-output .navbox-list{line-height:1.5em;border-color:#fdfdfd}.mw-parser-output .navbox-list-with-group{text-align:left;border-left-width:2px;border-left-style:solid}.mw-parser-output tr+tr>.navbox-abovebelow,.mw-parser-output tr+tr>.navbox-group,.mw-parser-output tr+tr>.navbox-image,.mw-parser-output tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style><style data-mw-deduplicate="TemplateStyles:r9671803">.mw-parser-output .tooltip-dotted{border-bottom:1px dotted;cursor:help}</style></div><div role="navigation" class="navbox authority-control" aria-labelledby="Authority_control_frameless&#124;text-top&#124;10px&#124;alt=Edit_this_at_Wikidata&#124;link=https&#58;//www.wikidata.org/wiki/Q81244#identifiers&#124;class=noprint&#124;Edit_this_at_Wikidata6129" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Authority_control_frameless&#124;text-top&#124;10px&#124;alt=Edit_this_at_Wikidata&#124;link=https&#58;//www.wikidata.org/wiki/Q81244#identifiers&#124;class=noprint&#124;Edit_this_at_Wikidata6129" style="font-size:114%;margin:0 4em"><a href="/wiki/Help:Authority_control" class="mw-redirect" title="Help:Authority control">Authority control</a> <span class="mw-valign-text-top noprint" typeof="mw:File/Frameless"><a href="https://www.wikidata.org/wiki/Q81244#identifiers" title="Edit this at Wikidata"><img alt="Edit this at Wikidata" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/10px-OOjs_UI_icon_edit-ltr-progressive.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/15px-OOjs_UI_icon_edit-ltr-progressive.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/20px-OOjs_UI_icon_edit-ltr-progressive.svg.png 2x" data-file-width="20" data-file-height="20" /></a></span></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">International</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><span class="uid"><a rel="nofollow" class="external text" href="http://id.worldcat.org/fast/1717209/">FAST</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://isni.org/isni/0000000121428792">ISNI</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://viaf.org/viaf/88801921">VIAF</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://id.oclc.org/worldcat/entity/E39PBJymtwvGypCRbR3YFTbGHC">WorldCat Entities</a></span></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">National</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><span class="uid"><a rel="nofollow" class="external text" href="https://authority.bibsys.no/authority/rest/authorities/html/90052813">Norway</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="http://www.bncatalogo.cl/F?func=direct&local_base=red10&doc_number=000041153">Chile</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="http://catalogo.bne.es/uhtbin/authoritybrowse.cgi?action=display&authority_id=XX897255">Spain</a></span> <ul><li><span class="uid"><a rel="nofollow" class="external text" href="http://catalogo.bne.es/uhtbin/authoritybrowse.cgi?action=display&authority_id=XX1074640">2</a></span></li></ul></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://catalogue.bnf.fr/ark:/12148/cb11920314s">France</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://data.bnf.fr/ark:/12148/cb11920314s">BnF data</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://cantic.bnc.cat/registre/981058514145006706">Catalonia</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://d-nb.info/gnd/118595830">Germany</a></span></li> <li><span class="uid"><span title="Popper, Karl R." class="rt-commentedText tooltip tooltip-dotted"><a rel="nofollow" class="external text" href="https://opac.sbn.it/nome/CFIV030536">Italy</a></span></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="http://uli.nli.org.il/F/?func=find-b&local_base=NLX10&find_code=UID&request=987007266491905171">Israel</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://urn.fi/URN:NBN:fi:au:finaf:000070318">Finland</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://opac.kbr.be/LIBRARY/doc/AUTHORITY/14138693">Belgium</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://id.loc.gov/authorities/names/n80032184">United States</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://libris.kb.se/64jlhtmq2grcvq4">Sweden</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://kopkatalogs.lv/F?func=direct&local_base=lnc10&doc_number=000021949&P_CON_LNG=ENG">Latvia</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://id.ndl.go.jp/auth/ndlna/00453131">Japan</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://aleph.nkp.cz/F/?func=find-c&local_base=aut&ccl_term=ica=jn19990006647&CON_LNG=ENG">Czech Republic</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://nla.gov.au/anbd.aut-an35428688">Australia</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://data.nlg.gr/resource/authority/record208021">Greece</a></span> <ul><li><span class="uid"><a rel="nofollow" class="external text" href="https://data.nlg.gr/resource/authority/record159566">2</a></span></li></ul></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://lod.nl.go.kr/resource/KAC199621977">Korea</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="http://katalog.nsk.hr/F/?func=direct&doc_number=000009732&local_base=nsk10">Croatia</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="http://data.bibliotheken.nl/id/thes/p068322496">Netherlands</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="http://mak.bn.org.pl/cgi-bin/KHW/makwww.exe?BM=1&NU=1&IM=4&WI=9810653789605606">Poland</a></span></li> <li><span class="uid"><a class="external text" href="https://wikidata-externalid-url.toolforge.org/?p=8034&url_prefix=https://opac.vatlib.it/auth/detail/&id=495/11310">Vatican</a></span></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Academics</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><span class="uid"><a rel="nofollow" class="external text" href="https://ci.nii.ac.jp/author/DA00189100?l=en">CiNii</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://mathscinet.ams.org/mathscinet/MRAuthorID/141205">MathSciNet</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://www.mathgenealogy.org/id.php?id=156913">Mathematics Genealogy Project</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://www.scopus.com/authid/detail.uri?authorId=16532100000">Scopus</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://zbmath.org/authors/?q=ai:popper.karl-r">zbMATH</a></span></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Artists</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><span class="uid"><a rel="nofollow" class="external text" href="https://musicbrainz.org/artist/0861d863-db8e-4a3e-898b-79a83b951fda">MusicBrainz artist</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://rkd.nl/en/explore/artists/440784">RKD Artists</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://www.getty.edu/vow/ULANFullDisplay?find=&role=&nation=&subjectid=500256162">ULAN</a></span></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">People</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><span class="uid"><a rel="nofollow" class="external text" href="https://www.deutsche-biographie.de/pnd118595830.html?language=en">Germany</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://trove.nla.gov.au/people/949358">Trove</a></span></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><span class="uid"><a rel="nofollow" class="external text" href="https://snaccooperative.org/ark:/99166/w6br8tcd">SNAC</a></span></li> <li><span class="uid"><a rel="nofollow" class="external text" href="https://www.idref.fr/027079430">IdRef</a></span></li></ul> </div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?useformat=desktop&type=1x1&usesul3=0" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://simple.wikipedia.org/w/index.php?title=Karl_Popper&oldid=9598536">https://simple.wikipedia.org/w/index.php?title=Karl_Popper&oldid=9598536</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Special:Categories" title="Special:Categories">Categories</a>: <ul><li><a href="/wiki/Category:1902_births" title="Category:1902 births">1902 births</a></li><li><a href="/wiki/Category:1994_deaths" title="Category:1994 deaths">1994 deaths</a></li><li><a href="/wiki/Category:20th-century_British_philosophers" title="Category:20th-century British philosophers">20th-century British philosophers</a></li><li><a href="/wiki/Category:Austrian_academics" title="Category:Austrian academics">Austrian academics</a></li><li><a href="/wiki/Category:Austrian_Jews" title="Category:Austrian Jews">Austrian Jews</a></li><li><a href="/wiki/Category:Austrian_scientists" title="Category:Austrian scientists">Austrian scientists</a></li><li><a href="/wiki/Category:Austrian_writers" title="Category:Austrian writers">Austrian writers</a></li><li><a href="/wiki/Category:Companions_of_Honour" title="Category:Companions of Honour">Companions of Honour</a></li><li><a href="/wiki/Category:Fellows_of_the_Royal_Society" title="Category:Fellows of the Royal Society">Fellows of the Royal Society</a></li><li><a href="/wiki/Category:Jewish_British_academics" title="Category:Jewish British academics">Jewish British academics</a></li><li><a href="/wiki/Category:Jewish_British_scientists" title="Category:Jewish British scientists">Jewish British scientists</a></li><li><a href="/wiki/Category:Jewish_British_writers" title="Category:Jewish British writers">Jewish British writers</a></li><li><a href="/wiki/Category:Jewish_philosophers" title="Category:Jewish philosophers">Jewish philosophers</a></li><li><a href="/wiki/Category:Knights_Bachelor" title="Category:Knights Bachelor">Knights Bachelor</a></li><li><a href="/wiki/Category:Naturalised_citizens_of_the_United_Kingdom" title="Category:Naturalised citizens of the United Kingdom">Naturalised citizens of the United Kingdom</a></li><li><a href="/wiki/Category:Refugees_from_Nazism" title="Category:Refugees from Nazism">Refugees from Nazism</a></li><li><a href="/wiki/Category:Scientists_from_Vienna" title="Category:Scientists from Vienna">Scientists from Vienna</a></li><li><a href="/wiki/Category:Austrian_philosophers" title="Category:Austrian philosophers">Austrian philosophers</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Articles_with_hCards" title="Category:Articles with hCards">Articles with hCards</a></li><li><a href="/wiki/Category:Webarchive_template_wayback_links" title="Category:Webarchive template wayback links">Webarchive template wayback links</a></li><li><a href="/wiki/Category:Articles_with_FAST_identifiers" title="Category:Articles with FAST identifiers">Articles with FAST identifiers</a></li><li><a href="/wiki/Category:Articles_with_ISNI_identifiers" title="Category:Articles with ISNI identifiers">Articles with ISNI identifiers</a></li><li><a href="/wiki/Category:Articles_with_VIAF_identifiers" title="Category:Articles with VIAF identifiers">Articles with VIAF identifiers</a></li><li><a href="/wiki/Category:Articles_with_WorldCat_Entities_identifiers" title="Category:Articles with WorldCat Entities identifiers">Articles with WorldCat Entities identifiers</a></li><li><a href="/wiki/Category:Articles_with_BIBSYS_identifiers" title="Category:Articles with BIBSYS identifiers">Articles with BIBSYS identifiers</a></li><li><a href="/wiki/Category:Articles_with_BNC_identifiers" title="Category:Articles with BNC identifiers">Articles with BNC identifiers</a></li><li><a href="/wiki/Category:Articles_with_BNE_identifiers" title="Category:Articles with BNE identifiers">Articles with BNE identifiers</a></li><li><a href="/wiki/Category:Articles_with_BNF_identifiers" title="Category:Articles with BNF identifiers">Articles with BNF identifiers</a></li><li><a href="/wiki/Category:Articles_with_BNFdata_identifiers" title="Category:Articles with BNFdata identifiers">Articles with BNFdata identifiers</a></li><li><a href="/wiki/Category:Articles_with_CANTICN_identifiers" title="Category:Articles with CANTICN identifiers">Articles with CANTICN identifiers</a></li><li><a href="/wiki/Category:Articles_with_GND_identifiers" title="Category:Articles with GND identifiers">Articles with GND identifiers</a></li><li><a href="/wiki/Category:Articles_with_ICCU_identifiers" title="Category:Articles with ICCU identifiers">Articles with ICCU identifiers</a></li><li><a href="/wiki/Category:Articles_with_J9U_identifiers" title="Category:Articles with J9U identifiers">Articles with J9U identifiers</a></li><li><a href="/wiki/Category:Articles_with_KANTO_identifiers" title="Category:Articles with KANTO identifiers">Articles with KANTO identifiers</a></li><li><a href="/wiki/Category:Articles_with_KBR_identifiers" title="Category:Articles with KBR identifiers">Articles with KBR identifiers</a></li><li><a href="/wiki/Category:Articles_with_LCCN_identifiers" title="Category:Articles with LCCN identifiers">Articles with LCCN identifiers</a></li><li><a href="/wiki/Category:Articles_with_Libris_identifiers" title="Category:Articles with Libris identifiers">Articles with Libris identifiers</a></li><li><a href="/wiki/Category:Articles_with_LNB_identifiers" title="Category:Articles with LNB identifiers">Articles with LNB identifiers</a></li><li><a href="/wiki/Category:Articles_with_NDL_identifiers" title="Category:Articles with NDL identifiers">Articles with NDL identifiers</a></li><li><a href="/wiki/Category:Articles_with_NKC_identifiers" title="Category:Articles with NKC identifiers">Articles with NKC identifiers</a></li><li><a href="/wiki/Category:Articles_with_NLA_identifiers" title="Category:Articles with NLA identifiers">Articles with NLA identifiers</a></li><li><a href="/wiki/Category:Articles_with_NLG_identifiers" title="Category:Articles with NLG identifiers">Articles with NLG identifiers</a></li><li><a href="/wiki/Category:Articles_with_NLK_identifiers" title="Category:Articles with NLK identifiers">Articles with NLK identifiers</a></li><li><a href="/wiki/Category:Articles_with_NSK_identifiers" title="Category:Articles with NSK identifiers">Articles with NSK identifiers</a></li><li><a href="/wiki/Category:Articles_with_NTA_identifiers" title="Category:Articles with NTA identifiers">Articles with NTA identifiers</a></li><li><a href="/wiki/Category:Articles_with_PLWABN_identifiers" title="Category:Articles with PLWABN identifiers">Articles with PLWABN identifiers</a></li><li><a href="/wiki/Category:Articles_with_VcBA_identifiers" title="Category:Articles with VcBA identifiers">Articles with VcBA identifiers</a></li><li><a href="/wiki/Category:Articles_with_CINII_identifiers" title="Category:Articles with CINII identifiers">Articles with CINII identifiers</a></li><li><a href="/wiki/Category:Articles_with_MATHSN_identifiers" title="Category:Articles with MATHSN identifiers">Articles with MATHSN identifiers</a></li><li><a href="/wiki/Category:Articles_with_MGP_identifiers" title="Category:Articles with MGP identifiers">Articles with MGP identifiers</a></li><li><a href="/wiki/Category:Articles_with_Scopus_identifiers" title="Category:Articles with Scopus identifiers">Articles with Scopus identifiers</a></li><li><a href="/wiki/Category:Articles_with_ZBMATH_identifiers" title="Category:Articles with ZBMATH identifiers">Articles with ZBMATH identifiers</a></li><li><a href="/wiki/Category:Articles_with_MusicBrainz_identifiers" title="Category:Articles with MusicBrainz identifiers">Articles with MusicBrainz identifiers</a></li><li><a href="/wiki/Category:Articles_with_RKDartists_identifiers" title="Category:Articles with RKDartists identifiers">Articles with RKDartists identifiers</a></li><li><a href="/wiki/Category:Articles_with_ULAN_identifiers" title="Category:Articles with ULAN identifiers">Articles with ULAN identifiers</a></li><li><a href="/wiki/Category:Articles_with_DTBIO_identifiers" title="Category:Articles with DTBIO identifiers">Articles with DTBIO identifiers</a></li><li><a href="/wiki/Category:Articles_with_Trove_identifiers" title="Category:Articles with Trove identifiers">Articles with Trove identifiers</a></li><li><a href="/wiki/Category:Articles_with_SNAC-ID_identifiers" title="Category:Articles with SNAC-ID identifiers">Articles with SNAC-ID identifiers</a></li><li><a href="/wiki/Category:Articles_with_SUDOC_identifiers" title="Category:Articles with SUDOC identifiers">Articles with SUDOC identifiers</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last changed on 14 June 2024, at 16:57.</li> <li id="footer-info-copyright">Text is available under the <a rel="nofollow" class="external text" href="//creativecommons.org/licenses/by-sa/4.0/">Creative Commons Attribution-ShareAlike License</a> and the <a href="/wiki/Wikipedia:Text_of_the_GNU_Free_Documentation_License" title="Wikipedia:Text of the GNU Free Documentation License">GFDL</a>; additional terms may apply. See <a class="external text" href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Terms_of_Use">Terms of Use</a> for details.</li> </ul> <ul id="footer-places"> <li id="footer-places-privacy"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy">Privacy policy</a></li> <li id="footer-places-about"><a href="/wiki/Wikipedia:About">About Wikipedia</a></li> <li id="footer-places-disclaimers"><a href="/wiki/Wikipedia:General_disclaimer">Disclaimers</a></li> <li id="footer-places-wm-codeofconduct"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Universal_Code_of_Conduct">Code of Conduct</a></li> <li id="footer-places-developers"><a href="https://developer.wikimedia.org">Developers</a></li> <li id="footer-places-statslink"><a href="https://stats.wikimedia.org/#/simple.wikipedia.org">Statistics</a></li> <li id="footer-places-cookiestatement"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Cookie_statement">Cookie statement</a></li> <li id="footer-places-mobileview"><a href="//simple.m.wikipedia.org/w/index.php?title=Karl_Popper&mobileaction=toggle_view_mobile" class="noprint stopMobileRedirectToggle">Mobile view</a></li> </ul> <ul id="footer-icons" class="noprint"> <li id="footer-copyrightico"><a href="https://wikimediafoundation.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><picture><source media="(min-width: 500px)" srcset="/static/images/footer/wikimedia-button.svg" width="84" height="29"><img src="/static/images/footer/wikimedia.svg" width="25" height="25" alt="Wikimedia Foundation" lang="en" loading="lazy"></picture></a></li> <li id="footer-poweredbyico"><a href="https://www.mediawiki.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><picture><source media="(min-width: 500px)" srcset="/w/resources/assets/poweredby_mediawiki.svg" width="88" height="31"><img src="/w/resources/assets/mediawiki_compact.svg" alt="Powered by MediaWiki" width="25" height="25" loading="lazy"></picture></a></li> </ul> </footer> </div> </div> </div> <div class="vector-header-container vector-sticky-header-container"> <div id="vector-sticky-header" class="vector-sticky-header"> <div class="vector-sticky-header-start"> <div class="vector-sticky-header-icon-start vector-button-flush-left vector-button-flush-right" aria-hidden="true"> <button class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-sticky-header-search-toggle" tabindex="-1" data-event-name="ui.vector-sticky-search-form.icon"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>Search</span> </button> </div> <div role="search" class="vector-search-box-vue vector-search-box-show-thumbnail vector-search-box"> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail"> <form action="/w/index.php" id="vector-sticky-search-form" class="cdx-search-input cdx-search-input--has-end-button"> <div class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Search Wikipedia"> <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="Special:Search"> </div> <button class="cdx-button cdx-search-input__end-button">Search</button> </form> </div> </div> </div> <div class="vector-sticky-header-context-bar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-sticky-header-toc" class="vector-dropdown mw-portlet mw-portlet-sticky-header-toc vector-sticky-header-toc vector-button-flush-left" > <input type="checkbox" id="vector-sticky-header-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-sticky-header-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-sticky-header-toc-label" for="vector-sticky-header-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-sticky-header-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div class="vector-sticky-header-context-bar-primary" aria-hidden="true" ><span class="mw-page-title-main">Karl Popper</span></div> </div> </div> <div class="vector-sticky-header-end" aria-hidden="true"> <div class="vector-sticky-header-icons"> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-talk-sticky-header" tabindex="-1" data-event-name="talk-sticky-header"><span class="vector-icon mw-ui-icon-speechBubbles mw-ui-icon-wikimedia-speechBubbles"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-subject-sticky-header" tabindex="-1" data-event-name="subject-sticky-header"><span class="vector-icon mw-ui-icon-article mw-ui-icon-wikimedia-article"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-history-sticky-header" tabindex="-1" data-event-name="history-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-history mw-ui-icon-wikimedia-wikimedia-history"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only mw-watchlink" id="ca-watchstar-sticky-header" tabindex="-1" data-event-name="watch-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-star mw-ui-icon-wikimedia-wikimedia-star"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-ve-edit-sticky-header" tabindex="-1" data-event-name="ve-edit-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-edit mw-ui-icon-wikimedia-wikimedia-edit"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-edit-sticky-header" tabindex="-1" data-event-name="wikitext-edit-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-wikiText mw-ui-icon-wikimedia-wikimedia-wikiText"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-viewsource-sticky-header" tabindex="-1" data-event-name="ve-edit-protected-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-editLock mw-ui-icon-wikimedia-wikimedia-editLock"></span> <span></span> </a> </div> <div class="vector-sticky-header-buttons"> <button class="cdx-button cdx-button--weight-quiet mw-interlanguage-selector" id="p-lang-btn-sticky-header" tabindex="-1" data-event-name="ui.dropdown-p-lang-btn-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-language mw-ui-icon-wikimedia-wikimedia-language"></span> <span>91 languages</span> </button> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive" id="ca-addsection-sticky-header" tabindex="-1" data-event-name="addsection-sticky-header"><span class="vector-icon mw-ui-icon-speechBubbleAdd-progressive mw-ui-icon-wikimedia-speechBubbleAdd-progressive"></span> <span>Add topic</span> </a> </div> <div class="vector-sticky-header-icon-end"> <div class="vector-user-links"> </div> </div> </div> </div> </div> <div class="vector-settings" id="p-dock-bottom"> <ul></ul> </div><script>(RLQ=window.RLQ||[]).push(function(){mw.config.set({"wgHostname":"mw-web.codfw.main-74fffdc954-xbsb8","wgBackendResponseTime":141,"wgPageParseReport":{"limitreport":{"cputime":"0.467","walltime":"0.577","ppvisitednodes":{"value":4392,"limit":1000000},"postexpandincludesize":{"value":74339,"limit":2097152},"templateargumentsize":{"value":20121,"limit":2097152},"expansiondepth":{"value":14,"limit":100},"expensivefunctioncount":{"value":39,"limit":500},"unstrip-depth":{"value":0,"limit":20},"unstrip-size":{"value":32019,"limit":5000000},"entityaccesscount":{"value":1,"limit":400},"timingprofile":["100.00% 516.128 1 -total"," 39.59% 204.350 1 Template:Infobox_Philosopher"," 38.74% 199.934 1 Template:Infobox_person"," 27.19% 140.323 1 Template:Authority_control"," 17.51% 90.354 8 Template:ISBN"," 9.78% 50.471 8 Template:Catalog_lookup_link"," 8.28% 42.738 2 Template:Sister"," 8.11% 41.877 1 Template:Wikiquote-en"," 8.11% 41.848 1 Template:Infobox"," 7.58% 39.111 2 Template:Side_box"]},"scribunto":{"limitreport-timeusage":{"value":"0.216","limit":"10.000"},"limitreport-memusage":{"value":3198056,"limit":52428800}},"cachereport":{"origin":"mw-api-int.codfw.canary-6d6fb97c68-hw2zd","timestamp":"20250224142458","ttl":2592000,"transientcontent":false}}});});</script> <script type="application/ld+json">{"@context":"https:\/\/schema.org","@type":"Article","name":"Karl Popper","url":"https:\/\/simple.wikipedia.org\/wiki\/Karl_Popper","sameAs":"http:\/\/www.wikidata.org\/entity\/Q81244","mainEntity":"http:\/\/www.wikidata.org\/entity\/Q81244","author":{"@type":"Organization","name":"Contributors to Wikimedia projects"},"publisher":{"@type":"Organization","name":"Wikimedia Foundation, Inc.","logo":{"@type":"ImageObject","url":"https:\/\/www.wikimedia.org\/static\/images\/wmf-hor-googpub.png"}},"datePublished":"2008-03-11T11:37:27Z","dateModified":"2024-06-14T16:57:01Z","image":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/4\/43\/Karl_Popper.jpg","headline":"Austrian-British philosopher of science and social and pol\u00edtica e falsificationism and for criticism of Plato, Hegel and Marx as totalitarian opponents of open society (1902-1994)"}</script> </body> </html>