WhatTruthIs
MarkJago
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Acknowledgements
Thisbookgrewoutofaninterestinthemetaphysicsandlogicof truthmaking.DuringmyfirstteachingjobatNottingham,mythen colleagueGonzaloRodriguez-Pereyrapublishedoneofthemost importantpapersontruthmaking,‘Truthmaking,Entailment,and theConjunctionThesis’(Rodriguez-Pereyra2006b).Whatstruck memostaboutthepaper,apartfromthewonderfullyclearand compellingmetaphysicalarguments,wasthatitcouldbedeveloped withalogicalsemantics.Gonzalohadsetouttruthmakingprinciples forconjunction,disjunction,andentailment,arguedfor(oragainst) onmetaphysicalgrounds.Sowhatkindoflogicdidtheseprinciples generate?Whatshouldthemodeltheorylooklike?Istartedtoplay around.Duringthistime,Gonzalowasawonderfulmentor,with endlesspatienceformyendlessmistakes.
Justoverayearlater,DavidArmstrongtemporarilyjoinedthe Nottinghamdepartment,andweco-taughtanMAclass(onTruth andTruthmakers,naturally).Inpreparingtheclass,wespokealot abouthisviewsontruthmaking(orrather,hespokeandIlistened).I learntalotfromhiminsixmonths.ThelasttimeIsawDavidwasat theAustralasianAssociationofPhilosophyconferenceinMelbourne, 2009.Tomysurprise,herememberedme,tookmetolunch,and askedhowmythoughtsontruthmakingwerecomingalong.Well, heretheyare,David!Sorryyoudidn’tgettoseethem.Iliketothink hewouldapproveofwhatI’vegothere,inoutlineifnotindetail:a staunchlyrealist,Aussie-inspiredtakeonreality.
Theresearchwhichmakesupthisbookbeganwithworkwith StephenBarkeronnegativestatesofaffairs.Sincenorespectable journalwantedtopublishapaperonnegativestatesofaffairs,I hadampleopportunitytodevelopourinitialideas.Onceyouhave negativestatesofaffairs,you’renotthatfarfromuniversaland negativeexistentialstatesofaffairs.Thenyou’vegotallyouneedfor
atheoryoftruthmaking.SoIreturnedtotheideasI’dbeendiscussing withGonzaloaboutthemetaphysicsoftruthmaking.
Atthistime,IwaslivinginAustralia,andweirdandwonderful logicswereeverywhere.Whatwouldalogicoftruthmakinglook like?Ihadlittleideaandstumbledaroundplenty,butgotsetonmy feetthroughdiscussionswithGregRestall,DaveRipley,Graham Priest,andZachWeber.
Ihadnoplansforabookontruth,anddidn’tparticularlywant towriteabookontruthmaking,worryingthatitwas(by2013or so)atopiconwhichtoomuchhadbeensaidalready.Deflationism ruled;‘correspondence’theoriesseemedverymuchoutoffashion. Yetanideanagged:ifyouhavetruthmakersaplentyinyourrealist metaphysics,plusanindependentcharacterisationofwhatmakes themtruthmakers,thenwhynotanalyse beingtrue intermsof having atruthmaker?
Whatsealedthedealwasrealisingthatthisidentificationoftruth withtruthmakinggivesusawayofdealingwiththeparadoxesof truth.I’dco-organisedtwoworkshopson PropositionsandSameSaying withAlbertAtkinandRachaelBriggs,whichgeneratedvery helpfuldiscussiononthenatureofpropositionswithDaveChalmers, KitFine,andJonathanSchaffer,aswellaswithAlbertandRachael.I wasluckyenoughtobeabletodiscusstheparadoxesoftruthwith DaveRipley,LionelShapiro,andEliaZardini,who’vewrittensome ofthemostimpressiveandinterestingrecentpapersonthesubject.I thoughtmytruthmakingapproachofferedsomethingsimpler,with bettermetaphysicaljustificationandfewerlogicalcosts.
Allthatremainedwastoputalltheseideastogether.Here’sthe result.
Manyoftheideasdiscussedherewerepresented,invariousstages ofdevelopment,intalksatconferencesandworkshops:Utrecht philosophydepartmentseminar,19May2017; Ground,Essence &Modality conference,Helsinki,8June2016; TheMetaphysics ofGrounding workshop,Dresden,30April2016; TheLightness ofBeing workshop,Uppsala,Sweden,16–17November2015; Aboutness workshop,Hamburg,3–4August2015; Midsummer
PhilosophyWorkshop,Edinburgh,30June2015; Truth&Logical Consequence workshop,Nottingham,10June2015; Discourseand PhilosophyColloquium,UniversityofAmsterdam,17April2015; UniversityofEdinburghPhilosophyResearchSeminar,30January 2015;UniversityofHertfordshirePhilosophyResearchSeminar,13 November2014;NewYorkLogicGroupseminar,15September 2014;StAndrewsresearchseminar,16November2013;Melbourne logicseminar,12November2010; AustralasianAssociationofLogic conference,Sydney,2–4July2010;UniversityofSydneyCurrent Projectsseminar,17May2010;ANUresearchseminar,22April 2010; AustralasianAssociationofPhilosophy conference,Melbourne, 5–10July2009;Adelaide-MelbourneLogicAxismeeting,Adelaide, 9–10May2009;and Because conference,UniversityofGeneva, Switzerland,15–17February2008.
I’dliketothankalloftheaudiencesatthesetalks,whocontributed valuablefeedbackonmyideas.Particulardebtsofgratitudeare owedinthisregardtoJaminAsay,FranzBerto,RachaelBriggs, DavidChalmers,AlisonFernandes,KitFine,BrandenFitelson,Allen Hazen,OleHjortland,DaveIngram,NickJones,JonLitland,EJ Lowe,PenelopeMackie,PeterMenzies,BryanPickel,GrahamPriest, GregRestall,DaveRipley,JonathanSchaffer,BenjaminSchneider, JonathanTallant,NathanWildman,andRobbieWilliams.
SeveralearlychapterswerereadattheNottinghamWork-inProgressseminar.Thankstoallthatcontributedideas,particularly DaveIngram,PenelopeMackie,JonRobson,andJonathanTallant. AaronGriffithandananonymousreadercarefullyreadtheentire bookforOUPandofferedmeawonderfullyextensive,helpfullistof suggestions.Youbothhelpedmetoimprovethetextnoend;thanks verymuch!ManythanksalsotoJonathanTallantandAndyFisher, myheadsofdepartmentatNottingham,whohavebeensupportiveas Iwrote;andtoPeterMomtchiloffatOUP,whohasbeenwonderfully encouragingthroughout.
Someoftheargumentsinthebookhaveappearedinpreviously publishedarticles.§3.3–§3.4drawon‘AdvancedModalizingProblems’, Mind,125(499),627–42,2016.§5.2–§5.4drawon‘TheCost
ofTruthmakerMaximalism’, CanadianJournalofPhilosophy,43(4), 460–74,2013.§5.5drawson‘BeingPositiveAboutNegativeFacts’ (writtenwithStephenBarker), Philosophy&Phenomenological Research,85(1),117–38,2012.§6.3–§6.5drawon‘FromNatureto Grounding’,in Fundamentality,ed.RickiBlissandGrahamPriest, OxfordUniversityPress,forthcoming.§8.2and§§8.5–8.7drawon ‘PropositionsasTruthmakerConditions’, Argumenta specialissueon Thinkingthe(Im)possible,2017/18.Finally,§9.7drawson‘Alethic UndecidabilityDoesn’tSolvetheLiar’, Analysis,76(3):278–83,2016.
AsIwrote,theworldseemedtoturnitsbackontruth.IntheUK,we sawaperfidiousTorygovernmentelected,hell-bentonharmingthe poorestandmostvulnerableinsociety;closelyfollowedbytheBrexit vote,andtheelectionofDonaldTrump.Ineachcase,established factwasignoredbypoliticians,themedia,andthevotingpublic. Politiciansandnewspaperscouldnow,itseemed,liewithimpunity. Wemustalwaysrememberthatthetruthisimportant;itisgoodfor us;anditisvaluableforitsownsake.
Onlyonethingismoreimportantinourlivesthanthetruth.The dayafterIfinishedwriting,AnnaandIfinallymarried,anditwas thehappiestdayofmylife.Thankyouforalltheloveandsupport.
Introduction
TheNatureofTruth
Thisisabook aboutwhattruthis.It’saboutthe property of beingtrue.Whatfeaturesdoesthatpropertyhave?What kindsofentitycanhavethatproperty?Whatmakesanentity haveorlackthatproperty?Theseandsimilarmetaphysicalquestions willbetotheforethroughoutmyinvestigation.I’llbelessinterested inhowwetalk,orhowwethink,abouttruth.Myfocusisonthe property beingtrue,ratherthantheword‘true’ortheconcept truth. Myanswertothequestion,‘whatistruth?’issimple.Tobetrueisto bemadetruebytheexistenceofasuitableworldlyentity.Orrather,it istostandinthe truthmaking relationtosomeentity.Trutharisesasa relationbetweenaproposition—thecontentofoursayings,thoughts, beliefs,andsoon—andanentity(orentities)intheworld.The property beingtrue isanexistentialproperty:itistheproperty there isan x suchthat x truthmakes—.Apropositionhasthisproperty whenitfillsthe‘—’gap.Itdoesthiswhenthereissomeentitywhich truthmakesthatproposition.
Aninvestigationintotruthmayfocusonthepropertyof beingtrue, orontheconceptof truth,oronthepredicate‘istrue’.(Asay(2013b, 2014)discussestheimportanceofthedistinction.)Myaiminthis bookisnotatogiveconceptualanalysisofourconceptoftruth;nor isittogiveadefinitionofourword‘true’.Ifthatweremyaim,I’dbe guiltyofofferingyouacircularanalysisordefinition.Butitisn’tmy aim.Myaimistocharacteriseandsaysomethinginterestingaboutthe
property beingtrue.I’lldothatbyfirstcharacterisingthe truthmaking relation,whichholdsbetweenworldlyentitiesandpropositions.I’ll sometimesexpressthisrelationwithphraseslike‘entity x makes propositions ⟨A⟩ true’.Butdon’tbemisledbythe‘makes—true’ construction.Therearenottwoelementshere, making and truth. Thereisasinglerelation, truthmaking,sometimesexpressedusing thephrase‘makes—true’.
Characterisingthe truthmaking relationisthemaintaskofthis book.Myaimisnottoprovideasetofnecessary-and-sufficient conditionsfortruthmakingtohold.Philosophershardlyeversucceed inreducinganimportantconcept–causation,orknowledge,or disposition–tosomeother,betterunderstood,notions.Buttheydo managetosayinteresting,informative(andsometimes,hopefully, true)thingsaboutconceptslikethese.Ininvestigatingtheseconcepts, wecancometounderstandsomethingoftheirnature,evenabsent necessary-and-sufficientconditionsfortheirapplication.Weshould havethesameaimfor truthmaking.(Thatsaid,Idoofferasetof necessary-and-sufficientconditionsfor truthmaking inchapter8.But thisanalysisdependsonmyaccountofwhatpropositionsare,which youmayormaynotaccept.Ihopetosaysomethinginterestingabout truthmaking,independentlyofanyparticulartheoryofpropositions.)
Fromcharacterisingthe truthmaking relation,itisbutashortstep tothecharacterisationof beingtrue intermsof makestrue:thelatter issimplytheexistentialgeneralisation(inthefirstargument)ofthe former.Supposethatpropertiesandrelationshave‘slots’,correspondingtotheargumentplacesintheirlinguisticrepresentations.Then truthmaking hastwoslots:thefirstforthetruthmaker(theentity thatdoesthetruthmaking),andthesecondforthetruthmadeentity, thetrueproposition. Beingtrue,bycontrast,hasjustoneslot,for aproposition.Weobtain beingtrue from truthmaking simplyby existentiallyquantifyingintothefirstslot:from —truthmakes— to somethingtruthmakes—.That,inshort,iswhattruthis.
DavidArmstrong(2004)suggestsatheoryoftruthintermsof truthmakingverymuchlikethis.Butitisunclearwhatkindoftheory heintendstooffer.Hestateshistheorybysaying:
p (aproposition)istrueifandonlyifthereexistsaT(some entityintheworld)suchthatTnecessitatesthat p and p istrue invirtueofT.(Armstrong2004,17)
Thequotedprincipleismostoftencalled truthmakermaximalism, thethesisthateverytruthhasatruthmaker.(I’lldiscusstruthmaker maximalisminchapter3.)Theprinciplehasbeendiscussedintensively intherecentliteratureontruthmaking(seeBeebeeandDodd2005b; LoweandRami2009),butit’srarelytreatedasatheoryoftruth. Ofthetwenty-threepapersinthe2015‘stateoftheart’collection UnifyingthePhilosophyofTruth (Achouriotietal.2015),for example,nonefindacentralrolefortruthmaking,andonlyone (Sher2015)isabroadlycorrespondence-to-the-facts-styletheory.
Inreviewingthesituation,MarianDavidsaysthat‘truthmaker theoryisnotequipped,andusuallynotdesigned,toanswerthe question“Whatistruth?”’(David2016).Asay(2014)arguesthat atheoryoftruthshouldbekeptdistinctfromadiscussionof truthmaking,for‘thefoundationalrole[truth]playsinourconceptual schemeisnotonethatneedstheaidofanycausalortruthmaking powers’(2014,162;seealsoAsay2013b,chapter4).Armstrong himselfdescribeshisprinciple,variously,asa‘theoryofthenatureof truth’and‘anecessaryandsufficienttruth-conditionfortruth’but ‘not…adefinition’(Armstrong2004,17).Myprojecthereisnot merelytogivetruth-conditionsfor‘istrue’,ortostateacondition whichholdswheneversomethingistrue.(That’showthequoted principleisoftenunderstood.)I’mwithArmstrong,atleastwhenhe talksofa‘theoryofthenatureoftruth’.Butratherthanexpressingthis theoryasabiconditional,asArmstrongdoes,Iwanttounderstandit asaclaim:thepropertyof truth isidenticaltothepropertyof being truthmadebysomething.
Thistruth-as-truthmakingapproachbearssomeresemblanceto theold correspondence theoryoftruthofRussell(1905/1994,1906, 1912,1940)andMoore(1901).If‘correspondence’meansonlythat foreachtruth,thereexistssomerelatedworldlyentity,thenthetheory I’moffering is acorrespondencetheoryoftruth.AsArmstrongsays,
‘correspondencedemandsacorrespondent,andacorrespondentfora truthisatruthmaker’(Armstrong1997,14).Butif‘correspondence’ impliesaone-to-onecorrespondencebetweentruthsandthingsinthe world,thenI’mout.Yourexistencemakesmanytruthstrue: thatyou exist, thatapersonexists, thatsomethingexists, thateitheryouexist orIexist,andmanymore.Butequally,onetruthmayhavemany truthmakers:youandIareeachperfectlygoodtruthmakersfor that eitheryouorIexist,asisthepairofus.Socorrespondenceinsome nebuloussense:yes.One-to-onecorrespondencebetweentruthsand worldlyentities:nothere.
We’llhavetoworkhardtomakethistruth-as-truthmakingtheory attractive;eventomakeitplausible.Whyshouldtherebeanythingto sayaboutwhattruthis,otherthanthat,ineachcase,it’struethat A ifandonlyif A?Whyshouldtruthshavetorelatetoaworldlyentity atall?It’struethatBertieissnufflingwhenhe’ssnuffling;butwhy shouldtherebesomefurtherentity,thestateofaffairs thatBertie issnuffling,thatmakesthattruthtrue?Andevenifthereisinthis specificcase,whythinkthesamegoesfor every truth?Evenifthere’s astateofaffairs thatBertieissnuffling,it’safurtherstep—anda bigoneatthat—tothinkthatthere’ssomeentityintheworldthat makesittruethatnoHobbitsexist.I’lldiscusstheseissues—oftruth, truthmaking,andtruthmakermaximalism—inPartIofthebook (chapters1–3).
Ifwe’regoingtomakeatheoryoftruthintermsoftruthmaking plausible,we’llneedtosaywhatkindofentitythetruthmakers are.I’lldevelopthelinethattheyare(typically)statesofaffairs.So whatarestatesofaffairs?Howdoesaparticularandaproperty,or someparticularsandarelation,gettogethertomakeupastateof affairs?Dostatesofaffairsalsomaketruetruthssuchas‘thereareno Hobbits’?Andifso,how?Doweneed negative statesofaffairs,and ifso,what are they,metaphysicallyspeaking?ThesearetheissuesI takeupinPartII(chapters4and5).
Wethencometoquestionsaboutthe truthmaking relationitself. Whatkindofrelationitis?Whatpropertiesdoesithave?Howcan wethinkaboutitinprecise,logicalterms?How(ifatall)doesit
relatetothenotionof metaphysicalgrounding?I’lltakeupthese issuesinPartIII(chapters6and7).
Atthispoint,withthesequestionsanswered,wehaveatheoryof truthonourhands.Butwecansaymore.Aswellassayingwhat truthis,andhowatruthgetstobetrue,wecansaywhat kind of thingtruthsare.Thoughts,beliefs,sentences,utterances:thesecanall betrueorfalse.Butthereisamorebasickindofentity,whichwecan usetounderstandwhetherathought,belief,sentence,orutteranceis trueorfalse.Thoughts,beliefs,sentences,andutterancesallhavea content.Theyexpressthatsuch-and-suchisthecase.Thatentity—the contenttheyexpress—isa proposition.WhenIthinkandthensay thatBertieisadorable,andwhenyoucometobelievethatheis, whatIthinkandsay,andwhatyoubelieve,allhaveincommonthe content thatBertieisadorable.Webelievethesamething,thesame proposition;andit’sthatpropositionthatmyutteranceexpresses. Propositionsarethe primary bearersofthetruth-values.Propositionsarethethingsthataretrue,orfalse,inthefirstinstance.A truebeliefisabeliefwithatruepropositionasitscontent;atrue utteranceisanutterancewhichexpressesapropositionthat’strue. Butwhatarepropositions?Doeshavingatheoryofpropositions helpussolveproblemsandparadoxescreatedbytruth?Itakeup thesequestionsinPartIV(chapters8and9).
WhichApproach:MetaphysicalorLogical?
StewartShapirowritesthat:
Therearetwobodiesofphilosophicalliteratureontruth. Oneoftheseisconcernedwiththemetaphysicalnatureof truth(orwhetherithassuchanature).Authorsdefendand attackvarietiesoftruth-as-correspondence,truth-as-coherence, deflationism,andthelike.…Theotherbodyofliterature concernstheparadoxes.Itseemsthatthereisverylittleoverlap betweenthesebodies….(Shapiro2009)
Myaiminthisbookistocombinetheseapproaches.Metaphysical approachestotruthneedtoaddressthetruth-theoreticparadoxes,
mostfamousofwhichistheLiarparadox,‘thissentenceisnottrue’. Ifatheoryoftruthdoesn’taddresstheparadoxes,thenthethreat ofincoherenceloomslarge.Butequally,weshouldn’tapproach asolutiontotheparadoxeswithoutconsideringwhattruthis.If wewerecompletelymetaphysicallyunconstrained,theparadoxes wouldbemuchlesshard.WithouttheT-scheme,forexample,the Liarparadoxwon’tgothrough.Butweseemtobemetaphysically committedtotheT-scheme,onthegroundsofwhatproperty truth is.Itisonlybycombiningbothmetaphysicalandlogicalmodesof investigationthatwegetafullandsatisfactorypictureofwhattruth is.
Andmorethanthat:eachapproachcanlearnfrom,anddraw supportfrom,theother.I’llargueforacertainviewofpropositions (chapter8)andarguethatitgivesusthebestresponsetothe paradoxes(chapter9).Thattheoryofpropositionsmakesessential useofsomemetaphysicalnotions,includingtruthmaking.IfI’mright, anditreallyisthebestlogicalsolutiontotheparadoxes,thenthatis astrongargumentinfavourofthatmetaphysicalapproach.
RealismandAnti-Realism
It’ssometimessaidbyphilosophersthatatheoryoftruthsettles thequestionof realism:ofwhethertheworldexistsindependently ofourknowledge,beliefs,orthoughts.Andit’softensaidthata theoryoftruthmakingcarriesacommitmenttorealism.Accordingto Armstrong,‘Todemandtruthmakersforparticulartruthsistoaccept arealisttheoryforthesetruths’(Armstrong2004,5),for‘realism aboutthetruthofaparticulartrueproposition[is]thecontentionthat itstruthisdeterminedbysomethingthatliesoutsidethatproposition’ (Armstrong2003,12).Bigelowfeelsthat,withouttruthmaking,‘I findIhavenoadequateanchortoholdmefromdriftingontothe shoalsofsomesortofpragmatismoridealism’(Bigelow1988,123). Heiltakestruthmakingtobe‘acentraltenetofrealism’(Heil2003, 61).
Ithinkthat’samistake.Atheoryoftruthtellsuswhat truth is; butitneedn’ttelluswhethertruthsmustbeknown,orknowable,by creatureslikeus.Similarly,atheoryoftruthmakingis,inprinciple, compatiblewithdifferentpositionsalongtherealist/anti-realist spectrum.Wemayholdthattruthsrequiretruthmakersbutthat thetruthmakersarebroughtintoexistencebyourthoughtsorother kindsofconceptualactivity,forexample.HereIagreewithAsay:
Therealism/anti-realismdebatedoesnotconsistinwhetheror notthetruthsofsomedomainhavetruthmakers,butrather whatthenatureorcharacterisofthosetruthmakers.Simply havingtruthmakersisnotsufficientforrealism.(Asay2012, 378)
Let’stakeaspecifictheoryasanexample.Suppose,withBerkeley (1710/1995),thatmaterialobjectsarenomorethanconstructions fromourperceptions.Thatis,materialobjectsexistallright,but they’rementalconstructions.They’renot‘outthere’intheworld, independentlyofourthinkingaboutthem,asweusuallythinkthey are.That’saparadigmanti-realisttheoryofobjects.(I’musing‘antirealist’heretomean,roughly,thatthingsaremind-dependent.I’mnot using‘anti-realist’inthe eliminativist sense,sayingthatsuch-and-such entitiesdon’texistatall.)Nevertheless,Berkeleyhastruthmakers fortruthsaboutmaterialobjects—atleast,forthosetruthssuchas thatBertieissnuffling.Myperceptionsexistand,forBerkeley,they makeittruethatBertieissnuffling.Now,Idon’tthinkforoneminute thatthat’stherightpictureofmaterialobjects.Butourtheoryof truth—merelysayingthattobetrueistobemadetrue—doesn’ttell usthat.
Truthmakingandrealismareindependentdoctrines.Nevertheless, debatesabouttruthhaveplayedapartinthequestionofrealism. Manyversionsofglobalanti-realismholdthattruthisepistemically constrainedoressentiallyknowable.Theideaunderliesmuchidealist, phenomenalist,andotheranti-realistthought.Berkeley(1710/1995), Kant(1781/1998,A146/B185)(withrespecttoappearances,as opposedtothingsinthemselves),Mill(1889),Ayer(1936),and
Dummett(1978)allseemtosubscribetothe knowabilityprinciple: thatalltruthsareknowable(byus,orbysomeidealisedversionofus). Theprinciplemaybemotivatedbyworriesaboutradicaldeception, leadingtomeaningskepticism(Putnam1979,1981;Button2013).
Idon’tknowwhetheranyofthisshouldbetakenaclaimabout thenatureoftruth.Wecanformulatetheintendedcontentof‘truths areknowable’withoutmentioningtruth:foranyproposition A,if A thenwe(orsomeonelikeus)canknowthat A.Whateveristhecase isknowablythecase.Theprincipleconcernsthenatureofreality,in thefirstinstance,andthenatureoftruthonlyasaconsequence.
Itisnopartofthenatureoftruth,orofreality,thatwhatistrue isknowable.Supposeitwere:if A thenit’spossibletoknowthat A.Nevertheless,there’ssometruth A thatisn’tknownbyanyone. So,byassumption,thattruthisknowable:it’spossibletoknowthat (A andnooneknowsthat A).Butthatisn’tpossibleatall.Forin thatsupposedpossibility,someoneknowsthat A,andyetalsoknows thatnooneknowsthat A.Whatsheknowsmustbethecaseandso, inthatsupposedpossibility,someoneknowsthat A andyetnoone knowsthat A:contradiction.
Thissimpleargument,duetoChurch(2009)andFitch(1963), isimmenselypowerful.Itshowsthatnotalltruthsareknowable, andhencethatitisnopartofthenatureoftruthtobeknowable. (Theargumentmayseemlikealogicaltrickatfirst,butoncareful inspectionthereasoningisimpeccable(Williamson1993).It’s effectiveevenifoneacceptsintuitionisticratherthanclassicallogic (Percival1990);evenifwethinkthatknowledgedoesn’tdistribute overconjunctions(Williamson1993);andevenifwethink,with Linsky(2009),thatknowledgeclaimsshouldbeexpressedinatyped logic(Jago2010).It’sthisargument,ratherthananyconsideration ofwhattruthis,thatputsmefirmlyintherealistcamp.)
Justwhatthisargumenttellsusaboutrealismandanti-realismis moot.Itshowsusthatanyviableanti-realismhastoavoidentailing theknowabilityprinciple(orelseallowthatalltruthsareinfact known).Perhapsthiscanbedone(Hand(2009)andJenkins(2009) offersuggestions),althoughI’mskeptical.Regardless,you’llnodoubt
noticemyrealistinclinationsthroughoutthisbook.
Whatifrealismisthebestphilosophicalstanceinsomebutnot allcases?Whatifthereareobjectivefactsofthematter,outtherein theworld,insomedomainsofenquirybutnotinothers?Therealist stanceonmaterialobjects—thattheyexistindependentlyofwhether wethinkaboutthem,andindependentlyofwhatweknowabout them—seemsveryplausible.Butwhatabouttruthsaboutwhat’s funny,orwhat’sartisticallyvaluable?Wright(1992,1996,2001)and Lynch(2009,2001)arguethatwerequiredifferenttruthproperties indifferentdomainsofdiscourse,correspondingtodifferentwaysof beingtrue(PedersenandWright2013).Irejectthis alethicpluralism (§§1.5–1.7):thereisbutonepropertyof beingtrue,andthat’sthe oneidenticalto havingatruthmaker.
OutlineoftheBook
Chapter1:SubstantialorInsubstantial?
I’llbeginbycontrastingthetwomaincontemporaryapproachesto truth.Thefirstclaimsthattruthconsistsinrelatingtotheworldin therightway.Apropositionistruewhenit‘correspondstothefacts’, whateverthatmaymean.I’llcallthisapproach,whichencapsulates manydifferenttheories,the substantial approachtotruth.(Sher (2016)givesanoverviewofsubstantialapproaches.)Thesecond approachfindssubstantialtheoriestobefartooheavy-duty.The proposition that A istrueifandonlyif A.That’sit:there’snothing moretosayaboutwhattruthis.Inparticular,there’snoneedtogo heavy-dutyandgetourselvescaughtupwith‘correspondence’or ‘facts’oranyofthat.Thisapproachtakestruthtobean insubstantial property.
Inthischapter,I’llpresenttworeasonsforthinkingthattheinsubstantialapproachwon’twork.I’llarguethattruthisasubstantial property.I’llalsodiscusstheissueofalethicpluralism,mentioned earlier:istherejustonepropertyoftruth,orapluralityfulfillingthe truth role?
Chapter2:ArgumentsforTruthmaking
Thischapterfocusesonargumentsthathavebeengivenforthinking thattruthsneedtobemadetrue.I’llarguethattheseargumentsare, forthemostpart,question-begging.Wecan’testablishthattruths need truthmakersunlesswefirstknowwhat truth is.Somystrategy isn’t to arguethat,giventhenatureoftruth,truthsmustbemadetrue.Instead I’llargue,onmetaphysicalgrounds,thattheworldcontainsstates ofaffairs.And,giventhatstatesofaffairsexist,certainpropositions willcorrespondtothem.Thosestatesofaffairsthenmakethose propositionstrue.Ourreasonforbelievingintruthmakingisbecause theworldismadeupacertainway.
I’llthenarguethat,ifeverytruthhasatruthmaker(asIclaimin chapter3),thereisanargumenttobestexplanationidentifying being true with havingatruthmaker.
Chapter3:TruthmakerMaximalism
Iftherearestatesofaffairs,andsomepropositionscorrespondto thosestatesofaffairsintherightway,thensometruthsaremade true.Butarealltruthsmadetrue?Ifnot,thentheanalysisoftruthin termsoftruthmakingcannotbecorrect.Soaweightisplacedonthe ideathatalltruthsaremadetrue.Thisis truthmakermaximalism. Whybelieveit?I’llprovideanargumentthatallpropositionsare madetrue.Thisisageneralargument,establishingthatalltruths haveatruthmaker,butitdoesn’ttelluswhatkindofentitythose truthmakersare.Thatisthetaskofchapters4and5.
Chapter4:StatesofAffairs
Statesofaffairsplayaprominentroleintruthmakingtheory.But whatarethey?Whatistheirnature?Aretheymadeupofparticulars, properties,andrelations?Ifso,how?Howaretheyassociatedwith languageandthought?Iconsiderthreeapproachestotheissue.On oneview,particulars,properties,andrelationsarecombinedbya fundamentaltie intostatesofaffairs.Onanotherapproach,states
ofaffairsareprimitiveentitieswithoutconstituents.Athirdview holdsthat,whilststatesofaffairsarecombinationsofpropertiesand particulars(orofrelationsandparticulars),thereisnoadditional ontologicaltiebetweenthem.Inthischapter,I’lldevelopandcontrast thesethreetheories.
Chapter5:EverythingandNothing
Bythispoint,I’veofferedametaphysicalaccountofstatesofaffairs suchas thatBertieisadorable.Thesemakethecorresponding propositionstrueinaverysimpleway.Buttherearemanytruths— suchas thatBertieisnotarhinoceros and thatthereexistno Vulcans—whichdonotseemamenabletothisanalysis.Giventhat we’veestablishedthatalltruthsaremadetrue,wenowneedtoask: whatmakessuchtruthstrue?Isurveythesuggestions.Idividethese intotwocamps.There’sthe parsimonious approaches,whichtryto explainhowsuchtruthsaretruewithoutintroducingspecialnew entities.Thenthere’sthe plenitudinous approaches.Theseconcede thatextraentitiesarerequiredtomakesuchtruthstrue.I’llnarrow downtheoptionstojustone:suchtruthsaremadetruebynegative statesofaffairs.
Negativestatesofaffairsarethebadboysofmetaphysics.ButI’ll arguethatwecanmakesenseofthem,andthattheyaregoodto havearound.I’lloffertwoaccountsofwhattheyare,metaphysically speaking.
Chapter6:TruthmakingandGrounding
Sofar,we’vecoveredwhichtruthsaremadetrue(allofthem!)and bywhat(statesofaffairs);butwe’vesaidrelativelylittleabout thetruthmakingrelationitself.Whatkindofrelationitis?What propertiesdoesithave?Whendoesatruthmakerforoneproposition therebygettobeatruthmakerforsomeother,relatedproposition? Andwhatrelation,ifany,doestruthmakingbeartothemetaphysical notionof grounding?
I’llarguethattruthmakingiscloselyalignedtoaparticularkindof groundingrelationbetweenentities(typically,statesofaffairs).And
I’llarguethatthekindofgroundinginquestionisamatterofthe naturesofobjectsandproperties.Thisapproachtellsussomething aboutthenatureoftruthmaking,andhenceoftruth.Italsohints thattruthmakingbearsacloserelationtothenatureofpropositions, whichI’llinvestigateinchapter8.
Chapter7:TheLogicofTruthmaking
Inthischapter,Ipresent truthmakersemantics.Aformalsemantics canhelpussystematiseintuitionsaboutthetruthmakingrelation,and that’stheaimhere.Truthmakersemanticscanbeseenasarefinement ofpossibleworldssemantics,withapplicationswherepossibleworlds semanticscanbeapplied,butwithoutmanyoftheissuesfacedby possibleworldssemantics.
FollowingFine(2014,2016),Idistinguishtworelatednotionsof truthmaking: exact and inexact.Exacttruthmakingholdswhena truthistruepreciselyinvirtueoftheentityinquestion.Inexact truthmakingextendsthisnotion:aninexacttruthmakerfora propositionisonewhichcontains,asapart,anexacttruthmaker forthatproposition.Foreachnotion,Ipresentalogicalsemantics andinvestigatetheentailmentrelationtowhichitgivesrise.The logicofinexacttruthmakingturnsouttocorrespondtoawellunderstandlogicalsystem:first-degreeentailment.Butthelogicof exacttruthmakingisnewandsurprising.Onthatlogic,conjunctions donotentailtheirconjuncts.Thisfeaturemakesthelogichighlyunusual.Iinvestigatesomeofitsfeaturesandprovideacharacterisation theorem,whichcharacterisesthesemanticnotionofexactentailment inpurelysyntacticterms.
Chapter8:TheNatureofPropositions
Thetruthmakingrelationiscloselyalignedtometaphysicalgrounding,itselfcloselyalignedtothenaturesofthegroundedentities (chapter6).So,weshouldexpecttruthmakingtobearacloserelation tothemetaphysicalnaturesofthetruths.Truthsarepropositions, andsoweshouldexpecttheretobeacloserelationbetweenour theoryoftruthmakingandourtheoryofwhatpropositionsare.
Thistheoryoftruthmakingsuggestsasimpleyetpowerfultheoryof whatpropositionsare.Theyareentitiesconstitutedbytheirpossible truthmakers(andperhapstheirpossiblefalsemakers,too).Theyare builtfromactualandpossiblestatesofaffairs,inawaythattellsus, veryprecisely,whatwouldcountasatruthmakerforthatproposition, wereittoexist.
Chapter9:DealingwithLiars
Manytheoriesoftruthcannotdealwiththetruth-theoreticparadoxes, whichincludetheLiar,‘thissentenceisnottrue’.Thatinitselfisan argumentagainstsuchtheories.NowthatI’veofferedatheoryin termsoftruthmaking,Imustshowhowitavoidstheseparadoxes. I’llbeginbyreviewingsomeattemptstosolvetheparadoxesby changingtheunderlyinglogicusedtogeneratetheproblem.I’llargue thattherevisionsrequiredaretoosevere.Instead,weshouldlookto ourtheoryoftruth.Iftruthistruthmaking,asI’veclaimedhere, thenwecaninvestigatetheparadoxesintermsoftruthmaking. Fortruthmakingreasoningtogetagrip,theremustbesome propositiontobemadetrue.Sowecanmakeprogressbyasking: whatpropositionsdotheparadoxicalsentencesexpress?
Onthetheoryofpropositionssetoutinchapter8,theLiarsentence doesn’texpressanypropositionatall.Propositionsareconstructed frompossibletruthmakers.Butnostateofaffairscanpossiblymake theLiartrue,andsotheLiardoesn’texpressapropositionatall.This blockstheparadox.Moreover,thissolutionisimmuneto‘revenge’ arguments,forallsuchargumentsmustfocusonsomecontent expressed.Thesamegoesfortheotherparadoxes.Isuggestthat thetruthmakingapproachistheonlyadequate,stableresponseto theparadoxes.That,initself,isastrongargumentinitsfavour.
