Download The power of moral arguments

Thepowerofmoralarguments
NONCOPYEDITEDVERSION,PLEASEDONOTQUOTE
HugoMercier
UniversitédeNeuchâtel
ThomasCastelain
UniversitédeNeuchâtel,CNRS,&UniversityofCostaRica
NafeesHamid
UniversityCollegeLondon&ARTISResearch
BradlyMarínPicado
UniversityofCostaRica
Thequestionoftheroleofreasoning,bycontrastwithintuitionandemotion,in
moraljudgmentanddecisionhasanimatedphilosophyforcenturiesand
psychologyforthepastfewdecades.Overthepastyears,anincreasingnumber
ofexperimentshaverevealedthatreasoningoftenplayslittleactiveroleinmoral
judgment(Haidt,2001).Inafamousstudy,participantscastanegativejudgment
onsiblingswhohadsexeventhoughitwasstressedthatnoharmhadcomeofit.
Crucially,manyparticipantsstillappearedtoholdontotheirnegativejudgment
afteralltheirreasonshadbeenrebutted(Haidt,Bjorklund,&Murphy,2000;
althoughsee,Royzman,Kim,Leeman,&others,2015).Inanotherexperiment,
theethnicityoftheprotagonistsinastorywasmanipulated.Thismanipulation
affectedparticipants’moraljudgmentsoftheprotagonists—yettheynever
defendedtheirjudgmentsinethnicterms,relyinginsteadonimpeccablebut
post-hocmoralprinciples(Uhlmann,Pizarro,Tannenbaum,&Ditto,2009).
Theseexperimentsdonotshowthatreasoningplaysnoroleinmoraljudgments,
buttheysuggestthatitmostlyplaysapost-hocroleoffindingjustificationsfora
judgmentthatisarrivedatintuitively.Reasoningmostlyplaysacausalrolewhen
itfailstofindanydecentmoraljustification,inwhichcasepeoplemightfeel
compelledtochangetheirmind(foranexamplewithmoralbehavior,see
Snyder,Kleck,Strenta,&Mentzer,1979).Afewexperimentshaverevealeda
moreactiveroleforreasoning,sothatmakingpeoplereasonmorecouldalter
theirmoraljudgments.Forinstance,inducinga‘reflectivemood’(bygiving
peoplelogicalproblemsthatrequirereflection)madepeoplemorelikelytogive
theutilitariananswerto‘sacrificialproblems’(Paxton,Ungar,&Greene,2012).
(Sacrificialproblemsaremoraldilemmasinwhichsomeonewouldneedto
sacrificeatleastonelifetosavemorelives—Sophie’schoicebeingthearchetypal
example.Thedeonticansweristorefusetosacrificethelife,theutilitarianoneto
sacrificeit.)
Onthewhole,theseresultsfitwellwithHaidt’sinfluentialSocialIntuitionist
Model(Haidt,2001).Inthismodel,moralreasoningplaysalimitedrole:itcan
influenceintuitivemoraljudgments,butdoessoonlyrarely.However,theSocial
IntuitionistModelleavesopenthepossibilitythatreasoningmightplayalarger
rolewhenpeopleexchangeargumentswitheachother,insteadofengagingin
solitaryratiocination:“inconversation,wherepeoplecanpointouteachother’s
flawsandgiveeachotherreasons,goodreasoningoftenemergesfromthedyad”
(Haidt&Bjorklund,2007,p.241).
TheroleplayedbyreasoninginmoraljudgmentaccordingtotheSocial
IntuitionistModelisverysimilartotheroleplayedbyreasoningmorebroadly
accordingtotheargumentativetheoryofreasoning(Mercier&Sperber,2011).
Thistheorysuggeststhatthemainfunctionofreasoningistoargue:toproduce
argumentsinordertoconvinceothers,andtoevaluateothers’argumentsin
ordertobeconvincedonlywhenwarranted.Inthisperspective,thelimited
effectsofindividualreasoningarereadilyexplainedbythefunctionofreasoning.
Solitaryreasoningwouldmostlyservethefunctionofpreparingoneselfto
defendone’sopinionsordecisions,inanticipationofpotentialcriticisms.Solitary
reasoningshouldthushaveaconfirmationbias,ormysidebias:itshouldmostly
findargumentsthatsupportthereasoner’sexistingbeliefs,andindeeditdoes
(Mercier,inpress).
Bycontrast,peopleshouldbeabletoevaluateothers’argumentsrelativelywell:
theyshouldrejectfallaciousargumentsandbeconvincedbystrongenough
arguments.Onthewhole,theexperimentalevidenceisconsistentwiththis
conclusion,atleastwhenpeoplecareabouttheargument’sconclusion(e.g.Hahn
&Oaksford,2007;Hoeken,Timmers,&Schellens,2012;Petty&Wegener,1998).
Indiscussion,theabilitytoproduceargumentstodefendone’spointofview,and
toevaluateothers’arguments,shouldcombineandyieldgoodoutcomes.People
putforwardargumentsfortheirrespectiveopinions,onlythebestarguments
withstandthecriticalexaminationoftheothergroupmembers,andthese
argumentsendupcarryingtheday.Inadiscussion,groupmembershavetimeto
refinetheirarguments,toaddresseachother’scounter-arguments,andto
combinebitsofinsightfromthedifferentmembersintoasolutionthatcanbe
betterthanthatofthebestmembers(Laughlin,2011).
Theefficacyofargumentation—andtheapparentdeficienciesofindividual
reasoning—arewellillustratedbythefollowingproblem(whichwewillcallthe
PaulandLindaproblem):
PaulislookingatLindaandLindaislookingatJohn.
PaulismarriedbutJohnisnotmarried.
Isapersonwhoismarriedlookingatapersonwhoisnotmarried?
Yes/No/Wecannottell
Thecorrectansweris‘Yes’:Lindaiseithermarriedornotmarried,andinboth
casesitistruethatapersonwhoismarriedislookingatapersonwhoisnot
married(ifLindaismarried,theshe’slookingatJohn,who’snotmarried;if
Lindaisnotmarried,thenPaul,whoismarried,islookingather).Yetmost
participants(typicallybetween80and90%)answer‘Wecannottell,’atypical
failureofindividualreasoning(Trouche,Sander,&Mercier,2014).
Whenparticipantswhohavefoundthecorrectanswerontheirownaregiven
thestandardargumentforthewronganswer,theydonotchangetheirmind.By
contrast,whenthosewhohaveprovidedtheintuitivebutwronganswerare
giventheargumentforthecorrectanswer(writtenbyanotherparticipant),
approximatelyhalfofthemaccepttheargumentandadoptthecorrectanswer
(Troucheetal.,2014;seealsoStanovich&West,1999).Thisshowsthatpeople
finditeasiertoevaluategoodargumentsthantoproducethemontheirown.The
contrastbecomesevenstarkerindiscussion.Whenparticipantsdiscussthe
probleminsmallgroups,asinglememberwhofoundthecorrectansweris
nearlysuretoconvincetheothermembers,eveniftheyunanimouslyand
confidentlysupportthewronganswer(Laughlin,2011;Moshman&Geil,1998;
Troucheetal.,2014).
Ifargumentationworksbestforproblemsthathaveademonstrablycorrect
answer,italsosubstantiallyimprovesonreasoningperformanceinother
domains:forinductiveproblems(Laughlin,Zander,Knievel,&Tan,2003),fora
varietyofwork-relatedproblems(e.g.Blinder&Morgan,2005;Mellersetal.,
2014),inschools(Mercier,2011;Slavin,1995),andinscience(Dunbar,1995;
Mercier&Heintz,2014).Mostoftheseexamples,however,areepistemic.What
aboutmorality?
Inthecaseofmoraljudgmentsanddecisions,ithasbeensuggestedthat
argumentationplaysalimitedrolebycontrastwithothersocialprocessessuch
astrustorconformity(Bloom,2010).People’smoralconvictionswouldblind
themeventostrongargumentsthatchallengetheirpointofview(Edwards&
Smith,1996).Whilethebulkoftheliteratureonmoralreasoningbearson
participantsinisolation,thereisstillsomedatathatspeaktothisissue.
Beforelookingatthedata,wemustlayoutsomepredictions.Intheepistemic
domain,itisoftenpossibletotellwhatthebest—oratleastabetter—answeris.
Inthemoraldomainthisisoftendifficult,butwemusttrynonetheless.Ifwe
assumethatmoraljudgmentsaimchieflyatgaugingwhetherpeoplewouldmake
goodcooperationpartners(e.g.Baumard,André,&Sperber,2013),thenthe
judgmentscanbeobjectivelymoreorlessaccurate.Soundmoraljudgmentsare
thosethataccuratelypredictindividuals’cooperativebehaviorstowardsthe
individualdoingthejudging.
Bysymmetry,goodmoraldecisionsaredecisionsthatmaketherelevant
audiencebelievewewouldbegoodcooperationpartners—decisionsthatplay
wellforourreputationasmoralindividuals(e.g.Baumard,André,&Sperber,
2013).Evaluatingmoraldecisionsismuchmoredifficultbecauseanydecision
cancarryawidevarietyofcostsandbenefitsfortheindividualontopofits
effectsontheindividual’smoralreputation.Thebestdecisioneverything
consideredisrarelythemostmoralone.
Thepredictionoftheargumentativetheoryofreasoningisthatargumentation,
onaverage,helpsindividualswhodisagreebutwhoseinterestsoverlapreach
betterbeliefsandbetterdecisions.Inthecaseofmoraljudgments,itmeansmore
accuratemoraljudgments—judgmentsthatallowformoreaccuratepredictions
ofsomeone’sfuturebehavior.Butinthecaseofdecisions,itdoesn’tmeanmore
moraldecisionsnecessarily,butbetterdecisionsoverall.Fromanevolutionary
pointofview,itwouldoftenhavebeenworthittobehaveinawaythatothers
mightperceiveasimmoralinordertogainotheradvantages(accessto
resources,tobettermates,etc.).Thisisaveryroughprediction,however.Wecan
getslightlymorefine-grainedpredictionsbylookingathowargumentation
works.
Ausefulwayofthinkingabouttheeffectsofargumentationisthat,when
argumentationworks,itisbyincreasingthecoherencebetweenthebeliefsofthe
audience(Sperber,2001;Thagard,2002).Forinstance,someonewhoprovides
thewronganswertothePaulandLindaproblemholdsincoherentbeliefs(i.e.
thewronganswerisincoherentwiththeinformationprovidedintheproblem).
Whensheacceptstheargumentforthecorrectanswer,herbeliefsbecomemore
coherent.Ifweassume,trivially,thatourbeliefsaremorelikelytobeaccurate
thannot,thenincreasedcoherenceshouldincreasetheaccuracyofourbeliefs
(see,e.g.,Thagard,2002).Inafewcases,increasedcoherencecanleadtoless
accuratebeliefs.Thisshouldhappenwhenthesubsetofbeliefsbeingrecruited
inargumentationismorelikelytobeinaccuratethanaccurate.Thisisplausibly
thecasefordiscussionsofscientifictopicsthatrelyonlyonintuitivebeliefsand
notonscientificdiscoveries(discussionsthatwouldhavehadverylittle
evolutionaryrelevance).
Inthecaseofmoraljudgmentsanddecisions,argumentationshouldplaythe
samerole.Inparticular,argumentationhasthepotentialtoincreasethe
coherencebetweenspecificjudgmentsanddecisionsandmoregeneralmoral
principlesoneiscommittedto.Still,coherencewithmoralprinciplesshouldonly
beoneofthefactorsbeingweightedinwhenmakingdecisions.
Theeffectofargumentsonmoralmatters—abriefliteraturereview
Unidirectionalarguments—argumentstowhichonecannotreply—aretypically
lesseffectiveatchangingpeople’smindsthananactualdiscussionandthe
exchangeofargumentsitenables.Yetevenunidirectionalargumentscan
influencepeople’smoraljudgmentsanddecisions.
Toshowthatargumentsinfluencemoralopinions,astandardmethodologyisto
measureparticipant’sopinions,exposethemtoanargument,andmeasuretheir
newopinions.However,evenifachangeisobserved,itcouldmerelyresultfrom
ataskdemand—participantsunderstandingwhatisexpectedofthem—orfrom
mereconformity—expositiontosomeoneelse’sopinions,whetheritiswell
supportedornot.Toshowthattheargumentmatters,argumenttypeor
argumentqualityhastobemanipulated.Whenthisisthecase,analternative
methodistocomparetheopinionsofparticipantswhohavereceivedone
argumenttotheopinionsofparticipantswhohavereceivedanotherargument,
ratherthantotheirprioropinions.
ThisiswhatPaxtonandcolleagues(2012)did.Theyaskedparticipantstoread
thestoryofsiblingincestmentionedatthebeginning.Theyprovidedoneoftwo
argumentstotheparticipants:astrongargument,whichsuggestedthatthe
feelingofdisgustfelttowardsincestwasnotwarranted,andaweakargument,
whichsuggestedthatmakinglovewasanormalexpressionofloveinany
relationship.Participantswerethenaskedtoratethemoralityofthesiblings’
behavior.Participantsexposedtothestrongargumentweremoreacceptingof
thesibling’sbehaviorthanthoseexposedtotheweakargument.This,however,
wasonlytrueofparticipantswhohadtimetoreflectonthearguments.
Participantswhowereaskedtoanswerveryquicklyafterreadingthearguments
werenotinfluencedbythestrengthofthearguments,andtheirratingsfellin
betweentheratingsoftheparticipantswhohadreflectedonthestrong
argumentandthoseoftheparticipantswhohadreflectedontheweakargument.
Thissuggeststhatbothargumentshadaneffect,albeitanoppositeone(the
weakargumentwasindeedappallinglybad).Thatargumentscanaffectevena
canonicalexampleofanemotionalmoraljudgmentisanimportantresult.
Studiesinpoliticalsciencehavealsoshownthatargumentscanaffectviewson
policythathaveastrongmoralcomponent.Forinstance,thedebate,intheU.S.,
overtheinheritancetax(or‘estatetax’)hasastrongmoraldimension—Isitfair
totaxpeoplewhowanttotransmittheirwealthtotheirchildren?Wouldthe
repealofthetaxcreateimmoralinequalities?(Graetz&Shapiro,2005;
Hochschild,1980).Itisalsoassociatedwithpoliticalpartisanship,with
Republicansbeingmorelikelytofavoritsrepeal(Krupnikov,Levine,Lupia,&
Prior,2006).Ithasbeensuggestedthatforsuchatopic,factualargumentswould
havelittleappealcomparedtomoralarguments(Graetz&Shapiro,2005).To
testtheeffectofargumentsonsupportfortheestatetax,Sides(2011;seealso,
Kuziemko,Norton,&Saez,2015)askedvoting-ageAmericanstheiropinionon
theestatetax.Beforegivingtheiropinions,somerespondentswereprovided
withoneofseveralarguments.Oneoftheargumentswasfactual—pointingout
whopaystheestatetax—whiletheothersweremoral.Onemoralargument
favoredtheestatetax—itavoidsthecreationofan“aristocracyofwealth”—
othersopposedit—e.g.it“infringesontherightoffamiliestopassalong
inheritancetotheirchildren.”
Thefactualandthemoralargumentsagainsttheestatetaxwereeffective.
Moreover,theywereequallyeffective,swayingapproximately10%of
respondentseach.Bycontrast,theargumentsagainsttheestatetaxhadnoeffect.
Thismightbeduetomostrespondentshavingalreadyconsidered—ontheirown
orthroughmediaexposure—theseargumentswhiletheymightnothave
consideredtheargumentssupportingthetax.Theseresultsshowthatevena
singlefactualargumentcanhaveasignificanteffectonamorallyandpolitically
loadedissue.Similarresultsregardingthepotencyoffactualargumentshave
beenobtainedforissuessuchasforeignaid(Gilens,2001)andincreasesin
teachersalaries(Howell,Peterson,&West,2000).
Analogousresultshavebeenobservedwithchildrenforpurelymoralbehaviors.
Primaryschoolchildrencouldbemadetosharemoreoftheirprizeswithpoor
childrenthanksto‘empathic’arguments(e.g.,“theywouldbesohappyand
excitediftheycouldbuyfoodandtoys...”)thanto‘normative’arguments(“we
shouldgivesomemoneytootherspoorerthanourselves...”)(Eisenberg-Berg&
Geisheker,1979;seealso,Kuczynski,1982).
Bycontrast,otherstudieshavefoundthatparticipantscouldbeverycriticalof
argumentsthatchallengetheirmoralpositions,suggestingthattheymightbeso
criticalastorejectaltogetheranychallengingargument,whateveritsstrength
(Edwards&Smith,1996;Taber&Lodge,2006).Forinstance,Edwardsand
Smith(1996)gavetheargumentssuchasthefollowingtoparticipantswho
eithersupportedoropposeddeathpenalty:
Sentencingapersontodeathensuresthathe/shewillnevercommit
anothercrime.Therefore,thedeathpenaltyshouldnotbeabolished.
(Edwards&Smith,1996,p.9)
Theyfoundthatparticipantswhoopposedthedeathpenalty,comparedto
participantswhosupportedthedeathpenalty,ratedsuchargumentasbeing
substantiallyweaker—indeedasbeingquiteweak.However,therejectionof
argumentsthatchallengeourpositionsmostlystemsfromourabilitytofind
counter-arguments(Edwards&Smith,1996;Greenwald,1968;Taber&Lodge,
2006).Forinstance,aparticipantwhoopposesthedeathpenaltywouldhaveno
troublefindingcounter-argumentsagainsttheargumentabove—forinstance,
thatalifesentencehasasimilaroutcomeatalowerhumancost.Fromthe
presentpointofview,theissuehereisn’tsomuchthatpeoplerejecttooeasily
argumentsthatchallengetheirpositions,butinsteadthattheyaccepttooeagerly
argumentsthatsupporttheirviews.Moreover,whengoodrebuttalstothe
counter-argumentexist,thentheyarelikelytobefoundinthecourseofa
discussion.
Thebestdemonstrationoftheeffectivenessofmoraldiscussioncomesfrom
casesinwhichthereisaclearmoralbenchmark.Thisoftenmeansstudieswith
youngchildrenwhohaven’tquiteadoptedwhatmostadultsseeasadesirable
moralstance.Inoneexperiment,9year-oldswerepresentedwiththisstandard
Piagetianmoralproblem,askingwhichofthetwochildrenisnaughtier:
Story1
OncetherewasalittleboycalledJohn.Hewasinhisroomandhismother
calledhimtodinner.Heopensthedoortothediningroombutbehindthe
doorthereisatraywithsixcupsonit.Johncouldn'thaveknownthatthe
traywasbehindthedoor.Heopenedthedoor,knockedthetrayandall
sixcupssmashedtothedoor.
Story2
OncetherewasalittleboycalledDavid.Onedaywhenhismotherwas
outhetriedtogetsomesweetsfromthecupboard.Heclimbedonachair
andstretchedouthisarm.Butthesweetsweretoohighandhecouldn't
reach,andwhilehewastryingtoreachitheknockedoveracupanditfell
andbroke.(Leman&Duveen,1999,p.575)
Aftertheyhadanswered,pairswereformedcomprisingonechildwhofavored
eachanswer.Mostofthesepairs(49outof60)agreedonthecorrectanswer
thatDavidwasnaughtier(seealso,Blatt&Kohlberg,1975).
Otherexperimentsillustratethetradeoffsbetweenamoraldecisionandagood
decisionaccordingtoothercriteria.Theseexperimentshaveusedeconomic
gamesinwhichmoralandfinancialincentivesconflict.Forinstance,inadictator
game,thedictator—whohasjustreceivedsomemoneyandisaskedifshewants
togivesometoanotherparticipantwhohasnotreceivedanymoney—can
choosetosharesomeofthemoney,ortokeepitallforherself.Insuchgames,
decisionsmadebygroupstendtofavorfinancialincentivescomparedto
decisionsmadebyindividuals—i.e.groupsgivelessthanindividuals(Bornstein,
Kugler,&Ziegelmeyer,2004;Bornstein&Yaniv,1998;Luhan,Kocher,&Sutter,
2009).Totheextentthatthedictators’reputationsarenotmeaningfullyatstake
(theotherparticipantsdonotknowwhothedictatorsare),thisisarguablya
morerationaldecision—andthuswhatweshouldexpectdiscussionstoyield.
Experimentsfromseveralotherfieldsarealsorelevant,eveniftheyprovideless
clear-cutresults.Juriesaresupposedtoadjudicateonmattersoffact,nottosolve
moraldilemmas—yetthereisoftenamoraldimensiontotheirverdicts.Studies
ofmockjuriessuggestthatdeliberationoftenimprovesjurydecisions
(Ellsworth,1989;Hastie,Penrod,&Pennington,1983).Similarly,whencitizens
discusspolicytogether,inthecontextofdeliberativepollingforinstance,they
usuallyreachmoreenlightenedopinions(Fishkin,2009;Mercier&Landemore,
2012).Inboththecasesofjuriesandofcitizendeliberation,mostofthe
improvementlikelystemsfromabettergraspoftherelevantfacts.Asarule,this
shouldtranslateintomoreaccuratemoraljudgmentsandbetterdecisions.
Theresultsreviewedhereshowthatargumentsanddiscussionscanaffectmoral
judgmentsanddecisions.Theyalsoshowthatnotallargumentsareequally
effective,whichsuggeststhataudiencesdodiscriminatebetweenargumentsof
variousstrengths.Discussionsseemtoinfluencejudgmentsanddecisionsina
waythatisbroadlycompatiblewiththeargumentativetheoryofreasoning.
Still,thisdomainremainsdrasticallyunderexplored.Wenowpresentthree
studiesthataimtofurtherinvestigatetheroleofargumentsanddiscussionson
moraljudgments.Ineachcase,wereliedondilemmasthathavebeenwell
studiedinmoralpsychology,evenifmostlyoutsideofanyargumentative
context.Thesestudiesareexploratory,andsowewillonlypresentanoutlineof
theproceduresandresults.
Study1:Effectsofmoralargumentsonmoraldilemmas
ThegoalofStudy1wastoreplicatePaxtonetal.(2012).1Inparticular,we
wantedtoestablishmorepreciselytheeffectstheargumentshadonthe
participants.InPaxtonetal.(2012),participantsreadthesiblinginceststory,
wereprovidedwithanargument(weakorstrong)supportingmoralleniency
towardsthesiblings,andthenhadtoprovidetheirmoraljudgments.Asaresult,
itisimpossibletotellwhetherpeoplemademorelenientmoraljudgmentsafter
seeingthestrongargument,ormoreseveremoraljudgmentsafterreadingthe
weakargument.Inthefirstexperiment,weusedadesignsimilartothatof
Paxtonetal.(2012),exceptthatwemeasuredmoralacceptabilityjustafterthe
participantsreadthestory,andthenaftertheyhadreadtheargument.Someof
theotherdifferenceswiththeexperimentofPaxtonetal.(2012)arethatwe
usedadifferentstrongargument(onewethoughtmightbestronger),andthat
weaskedotherquestionspertainingtomoraljudgments(regardingconfidence
forinstance,whicharenotanalyzedhere).
241participantswererecruitedthroughAmazonMechanicalTurk.Table1
displaystheacceptabilityratings(onascalefrom1—completelyacceptable—to
7—completelyunacceptable)beforeandafterpresentationofthearguments.
Giventhatweonlyprovidedparticipantswithargumentsformoralacceptability,
weonlypresentresultsfortheparticipantswhoseinitialmoraljudgmentswere
1Materialsandresultsforallexperimentsareavailableuponrequesttothefirst
author.
challengedbythisargument:theparticipantswhoseinitialanswerwasonthe
‘unacceptable’endofthescale(5,6,or7,N=156).
Argumentstrength
Initialjudgment
Finaljudgment
Strongargument
6.49(0.75)
6.06(1.4)
Weakargument
6.35(0.81)
6.15(1.16)
Table 1. Acceptability ratings (mean and SD) before and after receiving the
argument for participants whose initial ratings were strictly superior to 4
(Study 1).
Bothargumentsloweredtheunacceptabilityratings,butonlythestrong
argumentsdidsosignificantly(shiftinjudgmentforstrongarguments:M=0.43,SD=0.87,Mdn=0,onesampleWilcoxon:p<.001;forweakarguments:M
=-0.19,SD=0.78,Mdn=0,p=.058).Moreover,strongargumentsloweredthe
unacceptabilityratingsmorethanweakarguments(twosamplesWilcoxon:p<
.05).Thisresultsuggeststhatstrongargumentscanaffectmoraljudgments,even
onemotionallysalientissues.Moreover,thefactthatstrongargumentsdidso
morethanweakargumentssuggeststhatthisresultisnotanartifact(reflecting
taskdemandsoftheexperimentforinstance).
Paxtonetal.(2012)hadobservedsimilarresults,butonlywhentheyhadasked
participantstoreflectontheargumentsfortwominutes.Whenparticipants
weren’taskedtodoso,therewerenodifferencesbetweenstrongandweak
arguments.Inthepresentexperiment,theparticipantswerenotaskedtoreflect
onthearguments.Severalfactorscouldexplainthediscrepancybetweenthe
resultsofPaxtonetal.(2012)andours:differentarguments,different
participants,differentmethodologies.Inanycase,ourresultssuggestthat
specificallyaskingforaphaseofreflectionisnotnecessaryforparticipantsto
considermoralargumentsandweighthemasafunctionoftheirstrength.
Study2:Effectsofgroupdiscussiononmoraldilemmas
Theexperimentsthatdemonstratemostconvincinglytheefficacyofarguments
ingroupdiscussionsarethosethatpitaminoritywiththecorrectanswerwitha
majoritywiththewronganswer.Inordertofindananaloguetothissetupwith
moraljudgments,wereliedonaspecifictypeofsacrificialdilemmas:thosein
whichthepeoplewhohavetobesacrificedwoulddieeveniftheyweren’t
sacrificed.Sophie’schoiceisagoodexample:thechildthatissacrificedifSophie
makesachoicealsodiesifshedoesn’t.Insuchcases,theutilitariananswer—i.e.
sayingthatthesacrificeismorallyacceptable—hassometimesbeendeemed
superiortothedeonticanswer—i.e.sayingthatthesacrificeisnotmorally
acceptable(e.g.Greene,2008).Moreover,theutilitariananswerhasbeen
associatedwithSystem2processesinthesamewaythatthecorrectanswerto
intellectiveproblemshas(Greene,Morelli,Lowenberg,Nystrom,&Cohen,2008).
Onemightthereforeexpectparticipantswiththeutilitariananswertoconvince
participantswiththedeonticanswereveniftheyareinaminorityposition.
Totestthisprediction,weasked110participants(firstyearpsychologystudents
inFrance)tojudgetheactionsinasacrificialmoraldilemmatwotimesinarow.
Intheindividualphase,theyansweredontheirown.Inthegroupphase,they
wereaskedtodiscussthatsamedilemmainsmallgroups(26groupsof4or5
participants)andtoreachaconsensualanswer.Twosacrificialdilemmaswere
used,eachforapproximatelyhalfoftheparticipants,andtheresultsdonotdiffer
acrossdilemmas,sotheyareanalyzedtogether.
Inordertocomparetheresultsofthetwophasesmoreeasily,wecomputeda
scoreforeachdiscussiongroupandtheequivalentnominalgroupforthe
individualphase(i.e.thestatisticalaverageoftheparticipantsthatcomposea
givengroupduringthegroupphase).Deonticanswerswerecodedas0and
utilitariananswersas1,andthegroupaverageswerenormalizedtothe[0,1]
range.Thus0meansthateverygroupmemberprovidedadeonticanswerwhile
1meansthateverygroupmemberprovidedautilitariananswer.Atthe
individualphase,theaveragegroupscorewas0.25(SD=0.24,Mdn=0.22).At
thegroupphase,itwas0.24(SD=0.40,Mdn=0).Discussionhadnooverall
effectsonmoraljudgments(ExactWilcoxon-Signed-RankTest,Z=1.09,p=0.27,
r=0.15).Analysisofthegroupsinwhichtheutilitariananswerwasdefendedby
aminorityofmembersconfirmsthispattern.Therewereninesuchgroups
(typicallyoneutilitarianparticipantagainstamajorityofthreedeontic
participants).Inonlyoneoftheseninegroupsdidtheutilitariananswer
convincethegroup.
Previousstudieshadshownthatgroupdiscussiondoesnotconsistentlyleadto
moreutilitariananswers.Inonestudyparticipantswereaskedtoallocatethe
budgetofa(hypothetical)hospitalbetweenpatientsrequiringmoreorless
expensivetreatments.Theparticipantshadtomakethisdecisionafterextensive
discussionwithpeers.Lessthan10%ofthegroupsconvergedontheutilitarian
answerwhichconsistsinallocatingallthemoneytothepatientswhichthe
cheapesttreatments(holdingeverythingelseequal).Mostgroupsagreedthat
thisdecisionwouldbeunfair(McKie,Shrimpton,Richardson,&Hurworth,
2011).
Asweconductedtheexperiments,someconcernswiththematerialsemerged.
Althoughsomeparticipantswereemotionallyaffectedbythestories,many
seemedtonottakethescenariosveryseriously.Thisissuggestiveofaframeof
mindquitedifferentfromtheoneinvolvedinreallifemoraljudgments—
especiallyjudgmentsonsuchdramaticissues.Thisisonlyaninformal
observation,butitconvergeswiththeresultsofBaumanetal.(2014),which
suggestedthatmanyparticipantsdonottakesomedilemmasseriously(intheir
case,trolleydilemmas).
Study3:Effectsofgroupdiscussiononmoraldilemmasinatraditionalpopulation
Allofthestudiesreviewedabovehavebeenconductedinso-calledWEIRD
(WesternEducatedIndustrializedRichDemocratic)populations(Henrich,Heine,
&Norenzayan,2010).Ithasbeensuggestedthat,acrossseveraldomains,
membersofthesepopulationsareoutliers:notonlyaretherecross-cultural
differences,butWEIRDpeopleareatanextremeofthespectrum.Forinstance,
theyseemtobethemostindividualisticpopulationeverstudied.Cross-cultural
studieshaveevidenceddifferencesrelevanttomoralpsychology(e.g.Haidt,
Koller,&Dias,1993;Shweder,Mahapatra,&Miller,1987).Whatismostrelevant
here,however,aretheeffectsofargumentsanddiscussionsonmoraljudgments
anddecisions.Doweobservethesamepatternsinotherculturesthatwedoin
WEIRDcultures?Tostartansweringthisquestion,weconductedapreliminary
studywithmembersofatraditionalpopulation.Thepopulationstudiedwere
indigenousMayafromGuatemalawhopracticesubsistencefarming,are
preliterateand,forthemostpart,donotspeakSpanish(N=54,allfemale,for
moreinformationaboutthepopulation,see,Castelain,Girotto,Jamet,&Mercier,
inpress).Suchtraditionalpopulationshavebeenshowntodifferinmany
respectsfromWEIRDpopulations,evenforapparentlybasiccognitive
mechanisms(Henrichetal.,2010).
Theparticipantswereaskedtoprovideananswertoanadaptationofthe
standardHeintzdilemma(Kohlberg,1981).Inthisdilemma,Miguel(inour
version,Heintzintheoriginal)stealssomemedicinesthatarerequiredtosave
hiswife’slife.Inthepre-test,participantshadtotell,ontheirown,whether
Miguelwasrighttohavestolenthemedicineornot.Inthetestphase,the
participantswereaskedtodiscussthedilemmainsmallgroups(3or4
members)andtrytoreachaconsensus.Finally,inthepost-testtheyfacedthe
dilemmaontheirownagain.Duringthepre-testandthepost-test,participants
wereaskedtojustifytheiranswers.Theirjustificationsweretranslatedfrom
K’iche’intoSpanishandcoded.Thejustificationswerefirstcodedsimplyasa
functionoftheanswertheysupported.Theywerethencodedusingthe
assessmentmanualofColbyandKohlberg(1987),whichwasdesignedto
interpretthejustificationsfromsuchKolbergiandilemmas.
Thesimplecodingofthejustificationsintermsofwhethertheysupporteda‘Yes’
(i.e.Miguelshouldhavestolenthedrugs)ora‘No’answer(i.e.Miguelshouldnot
havestolenthedrugs)revealedmanymismatchesbetweenthejustificationsand
theanswersprovidedbytheparticipants.Thisissuedidnotarisewhenweasked
thesameparticipantstocompleteothertasks(reasoningtasks)(Castelainetal.,
inpress).Wearenotsurewhatthecauseofthismismatchis.Theparticipants
mighthavemisunderstoodthequestion,sothattheythoughtthatanswering
‘Yes’meantthatMiguelshouldnothavestolenthedrugs(e.g.‘YesMiguelshould
becondemned’).Inanycase,wethoughtthatthejustificationswouldprovidea
morereliableguidetotheparticipants’thinking.Indeed,alljustificationscould
beunderstoodassupportingamoralstancetowardsMiguel’sactions,whetherit
wasacceptation(e.g.“bystealinghesavedhiswife”)orcondemnation(e.g.
“stealingisacrime”).TheseresultsarepresentedinTable3.
Answersupportedbythejustification
Pre-test
Post-test
Yes(heshouldhavestolenthedrugs)
36
41
No(heshouldn’thavestolenthedrugs)
18
15
Table 2. Number of justifications supporting the Yes and No answers at the
Pre-test and Post-test of Study 3.
Table1suggeststhatthediscussionbroughtveryfewchangesinthe
participants’answers.However,ifitistruethattherewaslittleevolutioninthe
aggregateanswers,thisstabilitywaslargelyduetoabalancebetweenthe
numberofparticipantswhowentfroma‘Yes’answertoa‘No’answer(8)and
thosewhowentfroma‘No’answertoa‘Yes’answer(13).Thirty-ninepercentof
participantsthuschangedtheirmindsduringthediscussions.Thatthese
changeswerenotmerelyrandomnoiseissuggestedbythefactthattheyalltook
placeamongparticipantswhowereexposedtodifferentviewsinthecourseof
thediscussion.Noneofthe13participantsbelongingtogroupswhich
unanimouslysupportedananswerchangedtheirmind,asignificantdifference
withthe21changesofmindsoccurringingroupsinwhichthetwoanswerswere
represented(Fischerexacttest,p<.001).
Discussionmightalsohavehadaneffectonthetypeofargumentsputforward
bytheparticipants.UsingtheKohlbergianscalefromColbyandKohlberg(1987),
wecomparedtherankingsofthejustificationsproducedatthepre-testandat
thepost-test.For15participantsthejustificationsrankedloweratthepost-test,
for12theyrankedthesame,andfor27theyrankedhigher.Abinomialtest
comparingthe15participantswhoseperformancedecreasedtothe27for
whomitincreasedrevealsatrendtowardsanimprovement(p=.088).
Theseresultssuggestthatwhilediscussionsaffectedmoraljudgments,there
werenoconsistenteffectinthedirectionofgreaterleniencytowardsthe
protagonistwhostoledrugsforhisdyingwife.Weshouldnotethatsomeofthe
argumentsprovidedsuggestthedilemmamighthavebeentoounrealisticforthe
participants,orthatitwasnotwellunderstood.Inparticular,manyparticipants
saidthatMiguelshouldhaveturnedtohiscommunitytohelphimbuythedrug
insteadofstealingit(“Miguelshouldaskhisneighborstoborrowhimsome
money”).Thiswasthecaseeventhoughitwasspecifiedinthedilemmathat
Miguelhadunsuccessfullytriedtoborrowmoneyfromeveryoneheknew.This
suggeststhateithertheparticipantswerenotpayingenoughattentiontothe
dilemma,orthattheyfoundthispremisetoounrealistic.Wecomebacktothe
potentialsignificanceofthisissueintheconclusion.
Conclusion
Theimpactofargumentsanddiscussionsonmoraljudgmentsanddecisions
remainsanunderstudieddomain.Thisisregrettableforatleastthreereasons.
Oneistheoretical:moredataisrequiredtoadjudicatebetweendifferenttheories
ofmoralreasoning.Anotherismethodological:analyzingthearguments
providedbyparticipantsandthewaytheydiscussmoraldilemmasprovides
tellingcuesregardinghowparticipantsthinkofthedilemmas.Inparticular,it
canemergeinthecourseofthediscussionthatmanyparticipantshaveeither
missedordismissedcrucialelementsofthedilemma(Study3aboveand
Royzmanetal.,2015),orthattheydonottakethedilemmaveryseriously(Study
2aboveandBaumanetal.,2014).
Thethirdreasonisthatitwouldmaketheexperimentsmoreecological.In
everydaylife,wegenerallycandiscussmoraldecisionsandmoraljudgments
withothers.Inparticular,wecanoftendiscussmoralviolationswiththe
perpetrator.Indeed,researchonexplanationsshowsthatpeoplespontaneously
justifytheirmoraltransgressions(Malle,2004).However,weknowverylittle
abouthowtheseexplanationsareevaluated,andhowtheyinfluencemoral
judgments.Takingthepossibilityofsuchfeedbackintoaccountmightchange
howwethinkabouthowmoraljudgmentsaremade(ontherelevanceofthe
logicofinteractionforthinkingaboutcognitivemechanisms,see,Levinson,
2006;Mercier,Bonnier,&Trouche,inpress).
Forinstance,peopletendtobeuncharitableinexplainingothers’bad
behaviors—inparticular,theyattributetotheircharacteractionsthatwould
oftenbebetterexplainedbysituationalfactors(forreview,see,Malle,2006).
Thismightseemsurprisinginlightofthetheoriessuggestingthatweassess
others’moralstandinginordertoselectreliablecooperationpartners.These
theoriesshouldpredictthatweaimatformingaccurateassessmentsofothers’
moralstanding.Takingthepossibilityoffeedbackintoaccountmightexplainthis
apparentdiscrepancy.Peoplemightstartwithanuncharitableinterpretation,
assumingthatifamorecharitableinterpretationiscorrect,thentheindividual
whobehavedwronglywillspontaneouslyprovideit.Unfortunately,wedonot
havemuchdata—andevenlessexperimentaldata—bearingontheseissues.
Wesuggestthatexperimentalresearchofeverydaymoraldecisionsand
judgments,andthediscussionsthatoftenaccompanythem,wouldbeavery
fruitfulavenueforstudy.Themoralproblemsmoststudiedintheexperimental
literature—fromincesttoSophie’schoice—bearlittleresemblancetothe
mattersthatoccupyoureverydaymoraldiscussions,suchas:isitokaytotake
stationeryfromwork,howmuchflirtingcansomeonemarriedengagein,what
countsasaninsultingjoke,etc.(althoughpeoplealsodiscussissuesofpersonal
relevancethathappentoalsobeofbroaderpoliticalrelevance,suchasfeminism,
see,e.g.,Mansbridge,1999).Findingproblemsthatparticipantscareabout
wouldbeespeciallyimportantinthestudyofmoralarguments,since
participantsaremorelikelytobeswayedbystrongargumentswhentheycare
abouttheissue(Petty&Cacioppo,1979).Thissuggeststhatresearchersshould
makemoreefforttofinddilemmaswhoseanswerisdirectlyrelevanttothe
participants.OurfailuretodosointhepresentStudies2and3mightexplain
whygroupdiscussiondidnothaveanyconsistenteffect.
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