The Evolution of Religion: How Cognitive By-Products, Adaptive Learning Heuristics, Ritual

16 Pages·2017·0.29 MB·English

The Evolution of Religion: How Cognitive By-Products,
Adaptive Learning Heuristics, Ritual Displays, and
Group Competition Generate Deep Commitments to
Prosocial Religio
Scott Atran, Joseph Henrich
To cite this version:
Scott Atran, Joseph Henrich. The Evolution of Religion: How Cognitive By-Products, Adaptive
Learning Heuristics, Ritual Displays, and Group Competition Generate Deep Commitments to Proso-
cial Religio. Biological Theory, Massachusetts Institute of Technology Press (MIT Press), 2010, 5,
pp.18-30. <ijn_00505193>
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The Evolution of Religion: How Cognitive
By-Products, Adaptive Learning Heuristics, Ritual
Displays, and Group Competition Generate Deep
Commitments to Prosocial Religions
ScottAtran Abstract
CNRS Understanding religion requires explaining why supernatu-
InstitutJeanNicod ralbeliefs,devotions,andritualsarebothuniversalandvari- 20
Paris,France ableacrosscultures,andwhyreligionissooftenassociated
5 & withbothlarge-scalecooperationandenduringgroupconflict.
JohnJayCollegeofCriminalJustice
Emerginglinesofresearchsuggestthattheseoppositionsresult
NewYork,NY,USA
fromtheconvergenceofthreeprocesses.First,theinteraction
&
ofcertainreliablydevelopingcognitiveprocesses,suchasour 25
ISRandFordSchoolofPublicPolicy
abilitytoinferthepresenceofintentionalagents,favors—as
10 UniversityofMichigan
AnnArbor,MI,USA an evolutionary by-product—the spread of certain kinds of
[email protected] counterintuitiveconcepts.Second,participationinritualsand
devotions involving costly displays exploits various aspects
JosephHenrich of our evolved psychology to deepen people’s commitment 30
DepartmentofEconomicsandDepartmentofPsychology tobothsupernaturalagentsandreligiouscommunities.Third,
15 UniversityofBritishColumbia competitionamongsocietiesandorganizationswithdifferent
Vancouver,BC,Canada faith-basedbeliefsandpracticeshasincreasinglyconnectedre-
[email protected] ligionwithbothwithin-groupprosocialityandbetween-group
enmity.Thisconnectionhasstrengtheneddramaticallyinre- 35
centmillennia,aspartoftheevolutionofcomplexsocieties,
andisimportanttounderstandingcooperationandconflictin
today’sworld.
Keywords
by-producthypothesis,credibilityenhancingdisplays,cultural 40
transmission,cooperation,groupcompetition,highgods,min-
imallycounterintuitive,morality,religion,riseofcivilization
March8,2010;revisedandacceptedMarch29,2010
BiologicalTheory5(1)2010,1–13.(cid:2)c2010KonradLorenzInstituteforEvolutionandCognitionResearch 1
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[An]advancementinthestandardofmoralityandanincreasein ulationsize,orinlarge-groupinteractionssuchasthoseasso-
thenumberofwell-endowedmen...who,frompossessinginahigh ciatedwithmanykindsofpublicgoodsorcommondilemmas 95
45 degreethespiritofpatriotism,fidelity,obedience,courage,andsym- (Boyd and Richerson 1988; Panchanathan and Boyd 2003;
pathy,werealwaysreadytogiveaidtoeachotherandtosacrifice NowakandSigmund2005;MathewandBoyd2009).Even
themselvesforthecommongood,wouldbevictoriousoverother more telling is that none of these mechanisms explains the
tribes.
variationincooperationamonghumansocieties,orthemas-
—CharlesDarwin,TheDescentofMan siveexpansionofcooperationinsomesocietiesoverlast10 100
millennia(Henrichetal.2005).
50 Thissynthesisintegratesinsightsfromstudiesofthecogni- Converginglinesoffieldandexperimentalevidencesug-
tivefoundationsofreligionwithevolutionaryapproachesto gestthatculturalevolution,buildingoncertaininnatecognitive
humancooperationtoderiveadeeperunderstandingoftheori- foundations,hasfavoredtheemergenceofbeliefsinpower-
ginanddevelopmentofprosocialreligions.Wearguethatthe ful moralizing deities concerned with the prosocial behav- 105
culturalevolutionofprosocialreligionsandthehistoricalrise iorofindividualsbeyondkin-andreciprocity-basednetworks
55 oflarge-scalecivilizationsinvolvethedynamicinteractionof (NorenzayanandShariff2008).Cross-culturalanalysisof186
theby-productsofadaptivecognitivemechanisms(e.g.,min- societies has found that larger and more complex societies
imally counterintuitive beliefs and overextended agent con- weremuchmorelikelytosubscribetopotentdeitiesdirectly
cepts), adaptive learning heuristics (e.g., emulation of suc- concernedwithmoralityandwillingtopunishnormviolators 110
cessfulandprestigiousindividuals),credibility-enhancingrit- (RoesandRaymond2003;Johnson2005).Studiesconducted
60 ual displays (e.g., self-sacrifice and costly commitments to acrossadiverserangeofsocietiesincludingforagers,farm-
seeminglypreposterousbeliefs),andculturalgroupselection ers,andherders,showthatprofessingaworldreligionpre-
forthosepackagesofrituals,devotions,andbeliefsthatbest dictsgreaterfairnesstowardephemeralinteractants(Henrich
sustainin-groupprosocialnorms(e.g.,monumentalundertak- et al. 2010). Experiments with North Americans show that 115
ings,sacredvalues). unconsciously activating religious concepts lead to reduced
65 Manyreligionsposeanevolutionaryenigmabecausethey cheatingandgreatergenerositytowardstrangers(Barghand
requirecostlycommitmentstobeliefsthatviolatebothcore Chartrand1999;MazarandAriely2006;ShariffandNoren-
aspectsoflogicalconsistencyandourintuitiveexpectations zayan 2007), except among ardent atheists. Together, these
abouthowtheworldworks,bothofwhichareotherwisecrucial cross-cultural, historical, and experimental findings suggest 120
forsuccessfullynavigatingtheworld(AtranandNorenzayan that (1) religion—as a phenomenon with potentially deep
70 2004).Religiouspracticesareoftencostlyintermsofmaterial roots (Klein 1989)—has not always been about high mor-
sacrifice(rangingfromhumansacrificetoprayertime),emo- alizinggodsand(2)modernworldreligionsmayhaveevolved
tional expenditure (inciting fears and hopes), and cognitive tocreateapotentlinkagebetweenthesupernaturalandthe
effort(maintainingconflictingmodelsaboutthenatureofthe prosocial.Thus,wehypothesizethatculturalevolutionarypro- 125
world).Oneanthropologicalreviewofreligiousofferingscon- cesses,drivenbycompetitionamonggroups,haveexploited
75 cludes:“Sacrificeisgivingsomethingupatacost....‘Afford aspectsofourevolvedpsychology,includingcertaincognitive
itornot,’theattitudeseemstobe”(Firth1963). by-products,tograduallyassemblepackagesofsupernatural
At the same time, the origin of large-scale cooperative beliefs,devotions,andritualsthatwereincreasinglyeffective
humansocietiesisalsoanevolutionarypuzzlebecausepeople atinstillingdeepcommitment,galvanizinginternalsolidarity, 130
frequentlycooperateandtradewithnon-relativesinephemeral andsustaininglarger-scalecooperation.
80 interactions(FehrandFischbacher2003).Thus,whiletheevo-
lutionarymechanismsassociatedwithkinship,reciprocity,and
OrdinaryCognitionProducesExtraordinaryAgents
reputation clearly influence cooperation in important ways,
they do not capture the fullest extent of human prosocial- Humansarepurpose-seeking,cause-inferring,story-tellingan-
ity.Kinshipcannotexplaincooperationamongnon-relatives imals(Gazzanigaetal.2009).AsHumenotedinTheNatural
85 (HenrichandHenrich2007),though“fictivekinship”—acul- HistoryofReligion,thegreatertheimpactofeventsonour 135
turalmanipulationofkinpsychology—maycontributetomo- lives,thegreaterisourdrivetoimposepurposeandcoherence
bilizinglargergroups(Johnson1987;Atran2003).Reciprocity onthoseevents.Thisviewisbackedbyarecentexperiment
does not suffice to explain cooperation beyond dense so- inwhichpeoplewereaskedwhatpatternstheycouldseein
cial networks, small villages, or tightly knit neighborhoods arrangements of dots or stock market figures (Whitson and
90 (HruschkaandHenrich2006;Allen-Araveetal.2008;Atran Galinsky2008).Beforeasking,theexperimentersmadehalf 140
2010).Neitherdirectnorindirectreciprocitycanexplaincoop- theparticipantsfeelalackofcontrol.Thosewhoexperienced
erationintransientinteractionsinlargepopulations,because alackofcontrolweremorelikelytoseepatternsandprocesses
reputationalinformationrapidlydegradesasafunctionofpop- underlyingtherandomness,suggestingthatunderuncertainty
2 BiologicalTheory5(1)2010
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wearemorelikelytofindpreternaturalexplanationsforthe uralagentswereharnessedbyculturalevolutiontobeginde-
145 randomness.Bothcross-culturalexperimentsandsurveysin- mandingcostlyactionsandcooperation,underthreatofdivine
dicatethatpeoplemorereadilyascribetotheveracityofnar- punishmentoroffersofsublimerewards.
ratives containing counterintuitive elements (e.g., miracles) Howdoourmindsmakeagentconceptsintogods?Cogni-
whenprimedwithdeath(NorenzayanandHansen2006),or tiveapproachesproposethatsupernaturalconceptsexploitor- 200
whenfacingdangerorinsecurity,aswithpleasofhopefor dinarymentalprocessestoconstructcounterintuitiveconcepts
150 God’sinterventionduringwartime(ArgyleandBeit-Hallahmi (Boyer2001;Atran2002;Barrett2004).Religiousbeliefsare
2000).Suchfindingshelpexplainbothcross-nationalanalyses counterintuitive because they violate universal expectations
showingthatacountry’sreligiosity(devotiontoaworldreli- about the world’s mundane structure. This includes the ba-
gion)ispositivelyrelatedtoitsdegreeofexistentialinsecurity siccategoriesofour“intuitiveontology”(i.e.,theontology 205
(NorrisandInglehart2004),andwhycertainkindsofreligions ofoursemanticsystem),suchasperson,animal,plant,and
155 enjoyrevivalsinchallengingtimes.Theissuethenbecomes: substance(Whythe1993;Sperberetal.1995).Experimental
how and why does purpose-seeking and cause-inferring so studiesrevealthatchildrenacrossculturesdonotviolatesuch
oftendeliversupernaturalagents? categoricalconstraintsinlearningwordmeaning;forexample,
Religioustraditionscenteronsupernaturalagents,suchas peoplecannotliterallymelt,andneithercananimalsjoke,trees 210
gods,angels,orancestorspirits.Thisincludesreligionssuch walk,norrockstire(Keil1979).ExperimentswithAmericans
160 asBuddhismandTaoism,whichdoctrinallyeschewpersoni- andIndiansillustrateagapbetweenreligiousutterancesand
fyingthesupernatural,butwhoseadherentsroutinelyworship thementalprocessingofreligiousconcepts(BarrettandKeil
anarrayofdeitiesthatbehaveinwaysthatviolateourintuitive 1996;Barrett1998).Whenaskedtodescribetheirdeities,sub-
expectationsabouthowtheworldworks(Pyysia¨inen2003). jectsproducedabstracttheologicaldescriptionsofgodsthat 215
Mundaneagentconceptsarecentralplayersinwhatpsychol- areableto(1)doanything,includinganticipatingandreacting
165 ogistsrefertoasfolkpsychology,associatedwithaTheoryof toeverythingallatonce,(2)knowtherightthingtodo,and
Mindmodule(s)(ToM),whichisacognitivesystemdevoted (3)dispenseentirelywithperceptualinformationandcalcu-
tomakinginferencesaboutthebeliefs,desires,andintentions lation.However,whenaskedtorespondtonarrativesabout
ofotherminds(Baron-Cohen1995).Recentfunctionalmag- thesesamegods,peopleinterpretedtheirdeitiesasbeingin 220
neticresonanceimaging(fMRI)studiesconfirmthatpeople’s onlyoneplaceatatime,puzzlingoveralternativeactions,and
170 statementsaboutGod’sinvolvementinsocialevents,aswellas lookingforevidencetomakeadecision.Inshort,peoplemen-
thedeity’spurportedemotionalstates,reliablyengageToM- tallyrepresentgodsusingourintuitiveontology,soabstract
relatedregionsofthebrain(Kapogiannisetal.2009). theologicalpropositionsgivelittleinsightintohowpeopleac-
Agentconceptsmaybehair-triggerinourcognitivepro- tuallythinkaboutsupernaturalagents(Malley2004).Much 225
cessing,allowingustoreadilyrespondunderuncertaintyto recentworksuggeststhisintuitiveontologyresultsfrom,or
175 potentialthreatsbyintelligentpredators(Guthrie1993).From interacts with, certain universal modes of causal construal,
thisevolutionaryvantage,agent’sproperevolutionarydomain includingfolkmechanics(objectcohesion,contact,andcon-
encompassesanimatespecies,butitsactualdomaininadver- tinuityinmovement),folkbiology(teleologicaldevelopment
tently extends to moving dots on computer screens, voices of species-like essences and relations), and folkpsychology 230
in the wind, faces in clouds, complicated contrivances like (intentional,goal-directed,interactiveagents).
180 eyes,andvirtuallyanycomplexdesignoruncertaincircum- Mostreligiousbeliefsminimallyviolatetheexpectations
stanceofunknownorigin(Sperber1996).Childrenandadults created by our intuitive ontology and these modes of con-
spontaneouslyinterpretthecontingentmovementsofdotsand strual,thuscreatingcognitivelymanageableandmemorable
geometricalformsonascreenasinteractingagentswithdis- supernatural worlds. For example, agents that resemble us 235
tinctgoalsandinternalgoal-directedmotivations(Heiderand emotionally,intellectually,andphysicallyexceptthattheycan
185 Simmel 1944; Bloom and Veres 1999; Csibra et al. 1999). movethroughsolidobjectsandliveforever(angels,ghosts,
Youngchildrenspontaneouslyoverattributeagencytoallsorts andspirits)fitthebill.Table1providesexamplesofminimal
ofentities(clouds,computers),andmaythusbepredisposed violations.
to construct agent-based representations of many phenom- Cognitiveapproacheshypothesizethatalthoughintuitive 240
ena(Keleman2004).Suchreliablydevelopingprogramspro- conceptstransmitwell,conceptsthatminimallydeviatefrom
190 videefficientreactionstoawide—butnotunlimited—range intuitiontransmitbetter,whilethosethatdeviategreatlycan-
ofstimulithatwouldhavebeenstatisticallyassociatedwith nottransmitsuccessfullybecausetheyoverloadcognitivepro-
thepresenceofdangerousagentsinancestralenvironments. cessesthatdriveinferentialreasoningandrelevance(Atranand
Mistakes,or“falsepositives,”wouldusuallycarrylittlecost, Sperber1991).Invisiblestatuesthatcryexistintwoplacesat 245
whereasatrueresponsecouldprovidethemarginofsurvival. onceandgethungryonlyonleapyearsarenoteasytoenter-
195 Thisreactivebiaswaslikelyadaptive,atleastuntilsupernat- tain.Minimallycounterintuitiveconceptsarerememberedand
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Table1. Mundanerelationsbetweenuniversalcategoriesandmodesofreasoning.Changinganyonecell(+to−or–to+)yieldsaminimalcounterintuition.
Thus,switchingthecell(−folkpsychology,substance)to(+folkpsychology,substance)yieldsathinkingtalisman;switching(+folkpsychology,person)to
(−folkpsychology,person)yieldsazombie(Barrett2000;AtranandNorenzayan2004).
BeliefDomains(andAssociatedProperties)
Folkmechanics Folkbiology Folkpsychology
Semantic Inert Vegetative Animate Psycho–Physical,e.g., Epistemic,e.g.,
Categories Hunger,Fatigue,etc. Belief,Desire,etc.
Person + + + + +
Animal + + + + −
Plant + + − − −
Substance + − − − −
retransmittedmorereadilythaneitherintuitiveorhighlycoun- rendersthemintuitivelycompellingyetfantastic,eminently 285
terintuitiveconcepts.Recallexperimentsindicatethatmini- recognizablebutsurprising.Cross-culturalexperimentsindi-
250 mallycounterintuitiveconceptsandbeliefsenjoyacognitive catethatsuchbeliefsgrabattention,activateintuition,mobilize
advantageinmemoryandtransmissionoverintuitiveconcepts inference, andcanaccommodate seeminglycontraryevents
andmundanebeliefs(BarrettandNyhof2001).Resultshave andinterpretations,inwaysthatfacilitatetheirmnemonicre-
beenobservedimmediately,aswellasafterathree-monthde- tention,culturaltransmission,andhistoricalsurvival. 290
lay,insamplesfromtheUnitedStates,France,Gabon,Nepal
255 (BoyerandRamble2001),aswellasfromMaya(Atranand
NaturalOriginsofFaith
Norenzayan2004).Whethercounterintuitiveconceptsarebe-
lievedin,orcommittedto,moreisanothermatter(thinkJesus Theabovehelpsexplainthesuccessof,forexample,folktales
vs. Zeus), which is addressed below (also see Gervais and andscriptures.However,thisapproachmissesthedifference
AQ1Henrichforthcoming). betweenMoses’miraclesandMickeyMouse’santics(Atran
260 Theadvantagesinmnemonicandtransmittabilityformin- 1998).Or,whythefaithfulsofonereligiondonotadoptbe- 295
imallycounterintuitiverepresentationsbegthequestionofwhy liefsinthegodsofotherreligionsoncetheylearnaboutthem
such representations don’t occupy most of scriptures, folk- (GervaisandHenrichforthcoming).So,thequestioniswhy AQ2
tales,andmyths.TheBibleortheKoran,forexample,involve dopeoplebecomedeeplycommittedtoparticularcounterin-
successions of mundane events—walking, eating, sleeping, tuitiveagentsorstories—socommittedthattheywoulddiefor
265 marrying, fighting, and suffering—interspersed with a few theirbeliefs? 300
counterintuitiveoccurrences,ofteninvolvingmiraclesorthe Weareaculturalspecies.Unlikeotheranimals,humans
appearance of supernatural agents. One explanation is that haveevolvedtorelyheavilyonacquiringbehavior,beliefs,
counterintuitive ideas are transmitted as elements in narra- motivations,andstrategiesfromothersintheirgroup.These
tivestructures.Studieshaveexploredthisbyexamining(1) psychological processes, shaped by natural selection, focus
270 thecognitivestructureoffolktales,and(2)therelativecul- ourattentiononboththosedomainsandindividualsthatlikely 305
turalsuccessofeachtale(Norenzayanetal.2006).Minimally to possess fitness-enhancing information (Henrich and Gil-
counterintuitivefolktales(containingtwotothreesupernatu- White2001;RichersonandBoyd2005).Humansociallearn-
raleventsorobjects)weresubstantiallymorewidespreadthan ing generates vast bodies of know-how and complex prac-
folktalescontainingfewercounterintuitiveelements(lessthan ticesthataccumulateandimproveovergenerations.Studies
275 two)orthosewithtoomanycounterintuitiveelements(more ofsmall-scalesocietiesshowthatsurvivalandreproduction 310
thanthree). aredependentoncumulativebodiesofinformationrelatedto
Inbrief,counterintuitiveconceptsandbeliefs,aslongas hunting (animal behavior), edible plants (seasonality, toxic-
they come in small doses, help people remember and pre- ity,etc.),medicalknowledge,technicalmanufacture,andso
sumably retransmit the intuitive statements, as well as the on(Liebenberg1990;HenrichandMcElreath2003;Henrich
280 underlying knowledge that can be inferred from them. A 2008). 315
smallproportionofminimallycounterintuitiveelementsgive Becauseofthedependencethathumanancestorsincreas-
a story a mnemonic advantage over stories with no or too inglyhadtoplaceonsuchcomplex,oftennonintuitive,prod-
many counterintuitive elements. This dual aspect of super- uctsofcumulativeculturalevolution,naturalselectionmay
natural belief sets—commonsensical and counterintuitive— have favored a willingness to rely on culturally acquired
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320 information—filteredthroughouradaptivebiases—overour beliefsaresupportedbydiagnosticactionsthatpermitanas-
directexperienceorbasicintuitions.Toseethis,considerthat sessment of the model’s underlying degree of commitment
many foragers process plant foods to remove toxins with- totheirexpressedbeliefs.Forexample,ifapotentialmodel
outconsciousknowledgeofwhathappenswithoutprocessing railsagainstprostitution,butthenusesprostitutesforhisown 375
(Beck1992).Suchfoodsoftencontainlowdosagesoftoxins clandestinerecreation,alearnershouldde-weightthismodel’s
325 thatcauselittleharmformonthsorevenyears,anddon’tbadly influenceinculturaltransmissionwithregardtoprosecuting
damagethefood’sflavor.However,suchtoxinswillaccumu- prostitution.Thismeansthatifamodel’sbeliefcauseshimto
lateandeventuallycauseseverehealthproblemsanddeath.A perform“costlydisplays”—thatis,actionsthatwouldbetoo
na¨ıvelearnerwhofavorshisownexperienceofeatingthefoods costlyforsomeonewithdifferentbeliefstoperform—learners 380
withoutthearduousprocessingwilldolessworkintheshort shouldbemorewillingtolearnfromthismodel.Ifamodelis
330 run,butpossiblydieinthelongrun.Placefaithintraditional successfulorprestigiousintheeyesoflearners,andperforms
practices,withoutunderstandingwhy,canbeadaptive.Simi- costlydisplayscueingdeepcommitmenttohisexpressedbe-
larly,manufacturingcomplextechnologiesormedicinesoften liefs,thenlearnersshouldmorereadilyadoptandbelievein(be
involveasequenceofimportantsteps,mostofwhichcannotbe committedto)themodels’expressedbeliefs(Henrich2009). 385
skippedwithoutproducinganinferioroutcome.Experimenta- Experimentalfindingssupportthis.Thus,youngchildren
335 tionisoflimiteduseinrearrangingordroppingstepsbecause aregenerallyunwillingtosampleanovelfoodofferedbya
evenarelativelysmallnumberofstepsyieldacombinatorial strangeras“somethingtoeat”withoutfirstseeingthestranger
explosion of possible alternative procedures. Learners must eatit(HarperandSanders1975).Developmentalstudiesofthe
havefaith,andcopyallsteps.Thissuggeststhatawillingness transmissionofaltruisticgivingshowthatneitherpreaching 390
tosometimesrelyonfaith—tobelieveinculturaltraditions norexhortationtocharityiseffectivewithoutopportunitiesto
340 overexperienceorintuitions—islikelyaproductofevolving observecostlygivingbymodels(HenrichandHenrich2007).
inaworldwithcomplexculturaladaptations. Studiesofchildren’sbeliefsabouttheexistenceofentitieslike
Supportingevidencecomesfromdevelopmentalpsychol- intangible germs, angels, and mermaids show that children
ogy,whichdocumentsapotenttendencyfor“over-imitation” onlysubscribetothoseagentswhomadultsseemtoendorse 395
in children, and recently demonstrated how deeply over- throughtheirdailyactions,andremainskepticalofunendorsed
345 imitationinfluencesouracquisitionandencodingofconcepts supernaturalagents(Harrisetal.2006).Similarly,interviews
(Lyonsetal.2007).Thiscomesacrossmoststarklyinstud- withadiversesampleofparentsfromhighlyreligiousChris-
iescomparingchildrenandchimpanzees.Whenbothspecies tian,Jewish,Mormon,andMuslimfamiliesrevealthatparents
observedemonstrationsofataskinvolvingmultiplesteps,chil- seereligionholdingtheirchildrenonavirtuouslifecoursepri- 400
drenaccuratelycopyallsteps,includingstepsthatdirectvisual marilybecauseoftheircostlyinvestmentsin“practicing(and
350 inspectionandareunnecessary.Chimpanzeesdosomecopy- parenting)whatyoupreach”(Marks2004).
ing,butskipunnecessarysteps,leadingthemtomoreefficient Thissuggestsanapproachtodevotions(fasting,celibacy,
repertoiresthanchildren(HornerandWhiten2005).Children etc.)andritualsashavingevolvedculturally(atleastinpart)
implicitly assume that if the model performed a seemingly todeepenpeople’scommitmentstocounterintuitivebeliefs. 405
unnecessary action, itwasprobably important, even ifthey Counterintuitivebeliefshaveamnemonicadvantage,butnot
355 cannotunderstandpreciselywhy. abeliefadvantage.Bothdirectexperienceandourownintu-
With the evolution of language, this faith in cultur- itionsoftencontradictcounterintuitivebeliefs,andrealitydoes
allytransmittedinformationbecamevulnerabletoexploita- not readily provide decisive evidence in their favor. (There
tion by individuals—particularly successful and prestigious aremanypotentiallycounterintuitivebeliefsthatcanbeem- 410
individuals—abletotransmitpracticesorbeliefstheythem- pirically grounded through arduous scientific effort—think
360 selves might not hold. Language makes exaggeration, dis- quantumteleportation,evolution,etc.—butcommonsenseand
tortion,manipulation,anddeceptioneasyandcheap.Before experiencedoesn’tfavoreventhesebeliefs.)Thisputscoun-
language,learnersobservedandinferredpeople’sunderlying terintuitivesatadisadvantagerelativetomundaneorintuitive
beliefsordesiresbytheirbehavior.Thosewishingtodeceive beliefs.Ritualsanddevotionscanhelpovercomethisdisad- 415
wouldhave toactuallyperformanactiontotransmitit.To vantagethroughactsofcostlycommitment(Henrich2009).
365 avoidbeingmanipulatedbymodelsproficientatalteringor In this view, costly ritual or devotional acts may have
exaggeratingcommitmentstocertainbeliefs,evolutionaryap- evolvedasameanstoconvincelearnersofthepersonalcom-
proaches suggest that humans may have evolved cognitive mitmentofeithertherestofthecongregation(exploitingcon-
abilities that examine the fit between a model’s words (ex- formistbiasesinourlearning)oroflocallyprestigiousmodels 420
pressedbeliefs)andactions.Infiguringoutwhotolearnfrom, (Henrich 2009). Rituals and devotions exploit our reliance
370 learnersconsiderbothamodel’scuesofsuccess,skill,and on diagnostic actions to deepen commitment to counterin-
prestige(amongothercues)andwhetheramodels’expressed tuitivebeliefs.Theyalsolinkperformanceofcostlyactsto
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socialsuccess,therebyperpetuatingthetransmissionofbelief– Becausethedeeplycommittedactuallybelieveintheagent’s
425 commitmentacrossgenerations.Formalculturalevolutionary incentives,sacrificesandritualsneedn’tseem(subjectively)
modelsshowthatcostlydisplays(e.g.,ritualsacrifice)canin- costly.
terlockwithandsustaincounterintuitivebeliefs,whichwould Religionshaveculturallyevolvedtodeployavarietyof
notbeotherwisesustainedbyculturalevolution.Bycontrast, other means to ratchet up faith and commitment. Faith in 480
fairytalesarecounterintuitive,easilyremembered,andmay otherwise inscrutable content is deepened and validated by
430 helptotransmitmoralmessagesbygrabbingattentionwith communion:collectivelyengagingemotionsandmotivations
themeshavingemotionalimpact;butnothingissociallyim- usingmusic,rhythm,andsynchrony. Ofpeoplereportinga
perativeorsacredaboutthemortheirmessage.Nooneinthe religiousexperience,musicisthesinglemostimportantelic-
learner’scommunitydemonstratesviacostlyactstheirdeep itoroftheexperience,followedbyprayerandgroupservices 485
commitmenttothetruthofsuchstories,actors,orideas. (Greeley 1975). Listeners as young as three years old reli-
435 Because of our adaptive need, at times, to rely wholly ablyassociatebasicemotions—anger,sadness,fear,joy—with
onculturalinformationinthefaceofinconsistentexperience musicalstructures(TrainorandTrehub1992).Recentstudy
orcontradictoryimplications,naturalselectionlikelyfavored findsthatstrangersactinginsynchrony—marching,singing,
something of a psychological immune system that cements anddancing—cooperatemoreinsubsequentgroupexercises, 490
adherencetoadoptedbeliefs.Experimentssuggestthatonce eveninsituationsrequiringpersonalsacrifice.Synchronousac-
440 peoplesincerelycommittoreligiousbeliefs,attemptstoun- tion(rhythmicallymovingtogether)increasescooperationby
derminethemthroughreasonandevidencecanstimulatethe strengtheningsocialbondsamonggroupmembers,evenwhen
strengtheningofpersonalcommitments(Festingeretal.1956). nopositiveemotionisattachedtothemovement(Wiltermuth
Sincemanyreligiousbeliefsarelogicallyinscrutableandim- andHeath2009).Theabilityofmusic,rhythm,andsynchrony 495
munetoempiricalfalsification,afailedprophecy(directevi- toinstillcommitmentandtrustisalsoapparentwhymilitary
445 dence)maymeanthatmoreintrospectionandcommitmentis drillsandroutinesdevelopedoverthecenturiestotrainsoldiers
needed. andbuildarmies(McNeil1982).
Theselinesofreasoningandevidencesuggestthatcom- Thisindicatesthatgroupsandinstitutionsthatsurviveand
mitmenttosupernaturalagentstendstospreadinapopulation spreadwillpossessbothcostlydisplays(devotionsandrituals) 500
totheextentitelicitscostlydisplays,usuallyintheformof ofcommitmentandvaluesthatglorifysuchsacrificesforgroup
450 ritualceremonies,offerings,devotions,andsacrifices.When beliefs.TheNavajo,forexample,areamongthemostsuccess-
communityleadersandcongregations demonstratecommit- fulcooperatorsandsurvivorsofNativeAmericangroups,with
ment to supernatural beliefs in costly rites, observers who men spending upwards of one-third, and women one-fifth,
witnessthesecommitmentsaremoreinclinedtotrustandfol- of their productive time on “priestly rites” (Kluckholn and 505
lowparticipants.Suchtrustandfollowingoftenextendtowider Leighton 1946). Historical studies suggest that early Chris-
455 setsofmundanebeliefsandassociatedactionsbecause(1)peo- tianityspreadtobecomethemajorityreligionintheRoman
pletendtofollow,andgivethebenefitofdoubtto,modelswith Empirethroughcostlydisplayssuchasmartyrdomandchar-
provensuccessandcommitmentinonevalueddomainasthey ity(e.g.,riskingdeathbycaringforsicknon-Christiansduring
moveintootherdomains(hence,advertisersgetfamouspeo- epidemics;Stark1997).Strengtheningthegroupthroughrit- 510
pletoselltheirwares)(HenrichandGil-White2001);and(2) ualparticipationandcostlydisplaysalsoappliestoavariety
460 many counterintuitive beliefs violate our intuitive ontology, ofmodernmovementsforcivilandhumanrightsthatgrow
andarethusliterallypreposterous(likemanypoetictropes); by“wagingpeace”inthebattleforpublicopinion,including
theycanonlybemeaningfullyinterpretedintermsexogenous thosemodeledonthenonviolentdoctrinesandcostlycommit-
to the beliefs themselves. Consequently, religious trust and ments(imprisonment,harassment,etc.)ofGandhiandM.L. 515
followingcarryover tootherbeliefsandactionsassociated King(Smith1996).Martyringspiritualleadersoftenstimu-
465 withritualizedactions,includingcooperativeworks,charity, latesthespreadoftheirideasbyprovidingpersuasivedisplays
commerce,moralnorms,andwarfare. oftheleader’sdeepcommitment.
Supernaturalagentsthatincentivizecostlysacrificeswill Below,wesketchaculturalevolutionaryprocessthatas-
tendtospread,creatinganemerginglinkagebetweendegree semblestheseotherwisedisparateelementsintoageneralac- 520
of commitment to belief and costly displays. For example, countoftheevolutionofreligions.
470 alongsideprohibitionsagainstvarioussocialills(e.g.,murder,
adultery,andtheft),GodcommandedtheIsraelitestokeepholy
Coevolution of Counterintuitive Beliefs and Norms
theSabbathorsufferdeath.Demandsforrituals,devotions,
forComplexSocieties
andsacrificesguaranteeintergenerationaltransmissionofdeep
commitments(AlcortaandSosis2005),aschildreninferdeep Counterintuitive beliefs are readily recalled and retransmit-
475 commitment from costly actions of adults (Henrich 2009). ted. Ritualsand devotions involving costlydisplays,music, 525
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ScottAtranandJosephHenrich
rhythm,andsynchronycanratchetupthebeliefin,andcom- andBoyd2001;PanchanathanandBoyd2004).Byaugment-
mitmentto,thesecounterintuitivebeliefs.Now,thequestions ingthesemechanisms,supernaturalbeliefshaveculturallyse-
are(1)howdotheseelementsofeffectiveritualsanddevotions lectiveadvantagesoverpurelysecularmechanisms(Johnson 580
getassembledandlinkedwithparticularsupernaturalagents?; 2005).Atthemargins,theadditionalpsychologicalthreatof
530 (2)whydothesesupernaturalagentssofavorprosocialbehav- supernaturalincentivesreducesthecostsofpunishingviola-
ior,byforbiddingstealing,lying,murdering,adultery,andso tors,providesathreatwhennohumaneyesarewatching,and
forth?;and(3)whydoesthisseemmoreprevalentinrecent maytiltthebalanceinsituationswhenthebenefitsofdefecting
andincreasinglylargeandcomplexsocieties?Arisingtide (chargingavastenemy)exceedthepotentialworldlycosts.If 585
ofevidencesuggeststhatreligiousbeliefs,rituals,devotions, atransgressorhasfaithindivineawarenessandretribution,
535 andsocialnormshavecoevolvedininterlockingculturalcom- then external policing, capture, and punishment “automati-
plexesinaprocessdrivenbycompetitionamongalternative cally”comefromwithin.Byreenforcingworldlymechanisms
complexes. wheretheyareweak(e.g.,monitoringlargepopulations),su-
As a species we rely heavily on acquiring key aspects pernaturalbeliefscanhelpextendthescaleandintensityof 590
ofourbehaviorbyobservingothers.Humansreadilyacquire cooperation. Third, when supernatural punishment is either
540 social strategies, practices, beliefs, and preferences via cul- indiscriminateorcollective,thirdpartieshaveadirectincen-
AQ3turallearninginwaysconsistentwithevolutionarypredictions. tivetokeepnormviolatorsinline.Ifpeoplebelievethattheir
Children acquire altruistic behaviors or other costly norms godwillpunisheveryone(say,byadrought)forthemisdeeds
viaobservationandinference,andwillspontaneouslyapply ofafew(e.g.,adultery),theneveryonehasanincentivetokeep 595
imitated standards to others, sanctioning them if necessary everyoneelseinline.
545 (HenrichandHenrich2007;Rakoczyetal.2008).Gamethe- Thefourthwayreligioncangalvanizeprosocialnormsis
oreticanalysesshowthatwhenculturallearningiscombined bymakinggodstheauthorsofsacredcanonsorvaluesthat
withsocialinteraction,avarietyofdifferentstablestates(i.e., authenticate society—in the minds of believers—as having
socialnormsorinstitutions)emerge.Unlikegenetictransmis- anexistenceaboveamereaggregationofitsindividualsand 600
sion,thisiseven trueinlargerscalecooperative endeavors institutions(Durkheim1995;Wilson2002).Beyondsimply
550 (HenrichandBoyd2001;PanchanathanandBoyd2004),in theauthorityofauthorship,theineffabilityofsacred“propo-
whichbothcooperativeanddefectingstatescanremainstable. sitions” (e.g., “God is merciful to believers,” or “this land
Whentheaforementionedcognitivemechanismsforweight- isholy”)effectivelyplacesthembeyondlogicalorempirical
ingcostlydisplaysareincludedaspartofculturallearning, scrutiny(Rappaport1999).Recentworkrevealsthatchildren’s 605
belief–actioncombinationsyieldmanydifferentstablestates, beliefsinGodasthecreatorofeverythingfavorsessentializ-
555 includingthoseinwhichtheactionsareindividuallycostly, ingofsocialcategories,meaningthatreligiousbeliefsabout
andpotentiallycooperative(Henrich2009). divinecreatorspredicttheinferringthatethnic/religiouscat-
Existenceofalternativestablesetsofnormsacrosshu- egory membership is stable (immutable: these effects seem
mansocietiescreatesconditionsinwhichcompetitionamong limitedtohumancategories,anddonotinfluencejudgments 610
groupswillfavortheemergenceofprosocialnorms—thatis, about artifacts or animals). This suggests that competition
560 normsthatleadtosuccessincompetitionwithothergroups. amongsocioreligiousgroupswillfavorbeliefsthatgalvanize
Themostimportantnormsarelikelytobethosethatincrease andreifygroupmembershipbyextendingourintuitivesystem
cooperation(e.g.,inwarfareandeconomicproduction)orre- foressence-basedinferences(usedforthinkingaboutbiologi-
ducewithin-groupconflict,byregulatingsexualrelationships calkinds;Atran1998)totherelevanthumansocialcategories 615
ormanagingdisputes.Becausethisprocessinvolvescompeti- (DiesendruckandHaber2009).Bysparkingourtendencyto
565 tionamongstablestates,modelingshowsthatitdoesnotsuffer essentializesomecategories(e.g.,biologicalspecies),beliefs
thechallengestypicallyassociatedwiththegeneticgroupse- insupernaturalcreatorsmayfacilitate(psychologically) the
lectionofaltruism(BoydandRicherson2002). unificationofdiversetribesintoasingle,stable,immutable
This process is capable of assembling those combina- people,andGod’speople. 620
tionsofsupernaturalbeliefs,rituals,anddevotionsthatmost Thesameevolutionaryprocesswillfavordistinctmarkers
570 reinforcecooperativeorotherprosocialnorms.Religiousel- ofgroupmembers,oftenintheformoftaboos.Theseemerge
ements can operate in at least four interrelated ways. First, asnonnegotiableprohibitionsaboutbeliefsandbehaviorsthat
observationandparticipationincostlyritualsarelikelytoin- systematicallycovarywithsacred(lessobservable)beliefsand
ducedeepcommitmenttoassociatednorms,leadingtogreater values(Durkheim1995;Wilson2002).Punishmentfortrans- 625
intrinsicmotivationtocomply(Henrich2009).Second,super- gression of taboos provides concrete markers and proof of
575 naturalpolicingandincentives(heavenvs.hell)canbuttress themeaningandimportanceofwhatissacredforasociety.
moreworldlynorm-sustainingmechanisms,suchaspunish- Together,sacredvaluesandtaboosboundmoralbehaviorat
ment,signaling,andreputation(Gintisetal.2001;Henrich the most basic level of conduct in society (sex, diet, dress,
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630 and greetings) and at the most general level (warfare, rule, harmony(nostealing,lying,oradultery),andfairexchange,
work,andtrade).Togetherwithreligiousrituals,devotions, (2)sexualandfamilyrelations(increasingreproductionofnew
andinsignia,suchpracticescanfosteracohesivegroupiden- adherents),and(3)theperformanceofcommitment-inducing
tityandincreasesolidarityvis-a`-visothergroups.Herereli- rituals(Roes1995;RoesandRaymond2003;Johnson2005). 685
gionexploitsandextendsour“tribalpsychology”thathaslong Tobetterpoliceandrewardadherents,thegodsofemerging
635 markedgroupboundariesthroughlanguage,dialect,anddress complexsocietiesneedmoreknowledgeofmortalbehavior
(McElreathetal.2003). (evolution of omniscience) and more power to reward and
For example, the Hebrew Kingdom of Judah used cir- punish(thus,anafterlifeinheavenorhell).Thisallowsgods
cumcision,dietarylaws,andaprohibitionagainstworkonthe tomonitorpeopleinephemeraloranonymoussituations,and 690
Sabbath(etc.)asdisplaysofcommitmenttotheirGod.This toprovidepotentincentives,iftheycaninstilldeepcommit-
640 enabledtheallianceofHebrewtribestosetthemselvesapart ment.Alongtheselines,beliefsinaneternal,blissfulafterlife
fromcoastalpeoples(e.g.,Philistines,Canaanites)andforged forthefaithfulemergedlikelyonlyafter500B.C.inEura-
aunificationthatwithstoodstrongerinvaders(e.g.,Egyptians, sia,withtheriseofcosmopolitanreligionssuchasHinduism,
Babylonians)(Sweeney2001).ViolatingtheSabbath,along MahayanaBuddhism,andChristianity(McNeil1991). 695
withidolatry,wereconsideredthegravestviolationsandpun-
645 ishablebydeath(Phillips1970).Thesewerebothcostlyand
TheReligiousRiseofCivilizations
arbitrarymarkersofcorporateidentityrelativetotheconcrete
needsofsociallifesharedwithothergroups(incontrastto Scholarshavelongsuspectedalinkbetweencertainreligious
prohibitionsonstealing,adultery,murder,etc.).Disregardof forms and the emergence of complex societies. In the 14th
these was considered a reliable signal of sin and failure of century,historianIbnKhalduˆnexamineddifferentwavesof
650 commitment.Fromthisperspective,groupsusingsuchcostly invasion in the Maghreb and argued that enduring dynastic 700
markerssucceedbecausethey(1)transmitcommitmentinthe powerstemsfromreligious“groupfeeling,”withitsabilityto
nextgeneration,(2)eliminate,oridentify,thoselackingsuf- unitedesires,inspirehearts,andsupportmutualcooperation
ficientcommitmenttothegroupanditsgod(s)(Irons1996; (Khalduˆn2005).Historicalworksuggeststhatthebeliefs,ritu-
SosisandAlcorta2003),and(3)psychologicallydemarcate als,andnorms(e.g.,inheritancerules,ethnicequality,judicial
655 thegroupinwaysthatengageourtendencytoessentializeand procedures)ofIslamspreadinitiallybyprovidingameansof 705
reifygroupboundaries. unifyingthewarringArabictribes,givingthemtheabilityto
Normsareoftenattached topowerful emotions (anger, cooperate,conquer,andgraduallyassimilatesurroundingpeo-
guilt, shame) that can be amplified by certain religious be- ples(Levy1957).ContemporarystudiesindicatethatIslam
liefsintodread,awe,oranxiety.Thisleadstostrongreactions spreadintoSub-SaharanAfricabydrawingpeopleintotighter
660 againstnormviolatorsthatrangefrombad-mouthingtoban- religiouslybasednetworksoftrustthatfacilitatetradeandeco- 710
ishment,andfrommanhandlingtomurder.Experimentsshow nomicsuccess(Ensminger1997).Asexpected,thisprocessis
thatwhennormsareassociatedwiththesacred,theybecome galvanizedbycostlydevotionsandrituals(fasting,frequent
emotionallychargedandlessinfluencedbymaterialcalcula- prayer,taboosonporkandalcohol)thatdemarcatebelievers
tionsandtradeoffs(Tetlock2003).Inconflictsituations,asin fromeveryoneelse.Similarconsiderationsapplytotheongo-
665 theMiddleEast,recentresearchrevealsthatmaterialoffers ingspreadofevangelicalProtestantisminAsia,Africa,and 715
fromonegrouptoanotherproposingthatnormsassociated LatinAmerica(Freston2001).
withsacredvaluesberelaxedorabandonedgeneratemoral The archaeological record reveals a clear, coevolution-
outrage,andincreasepeople’sreadinesstosupportlethalvio- ary connection between religion, ritual, and complex soci-
lence.Suchsacredvaluesappeartobesomewhatimmuneto eties. Recent finds indicate that rituals became much more
670 therationalityofrealpolitikorthemarketplace,implyingthat formal,elaborate,andcostlyassocietiesdevelopedfromfor- 720
a“business-like”approachtonegotiationsinconflictsinvolv- agingbandsintochiefdomsandstates(MarcusandFlannery
ingsacredvaluesmaybackfire(Atranetal.2007;Gingesetal. 2004;cfWhitehouse2004).InMexicobefore4000B.P.,for
2007;Dehghanietal.2009).Fromourperspective,increasing example,nomadicbandsreliedoninformal,unscheduled,and
thematerialincentivestoabelieverinexchangeforviolating inclusiverituals.Thesamegoesforcontemporaryforagers,
675 sacredvaluesmightresultinsubstantialincreasingofthesig- suchastheSanofAfrica’sKalaharidesert,whosead-hocrit- 725
nalingvalueobtainedfromrejectingthematerialpayoffs.The uals(e.g.,trancedancing)includeallcommunitymembers,
targetofthesignalmightbeGod,one’sfellows,orone’sself. andareorganizedaccordingtothecontingenciesofrainfall,
Thelinesketchedhereallowssomepredictionsaboutthe hunting,andillnesses(Lee1979).
historicalemergenceofsupernaturalagents.Godsofincreas- Then,withtheestablishmentofpermanentvillagesand
680 inglycomplexsocietiesshouldevolvetobemoreconcerned multi-village chiefdoms (4000–3000 B.P.), rituals are man- 730
with (1) in-group cooperation (help your co-religionists), agedbysocialachievers(prestigious“BigMen”andchiefs)
8 BiologicalTheory5(1)2010