Unto Others: The Evolution and Psychology of Unselfish Behavior

205 Pages·1998·35.39 MB·English

by  Elliott Sober

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UntoO thers
UntoO thers
TheE �oLutaionndP dychooLofg y
Unde/foiBhe ha�ior
ElliSooth te r
DaviSdl oaWni lson
HarvarUdn viersiPtyr ess
Cambgrei,Md assachusetts
LondoEnngl,a nd
1998
Copyri©gh 1t9 98b yt heP residaenndFt e lloowfsH arvarCdo llege
Toa ltrllutd everywhtehroewd,he o aed rpllfee14 11criea lly
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Allr ighrtess erved tow hatth emoitri Verde alalrye
Printientd h eU niteSdt atoefsA merica
LibroafCr oyn gCraetsasl oging-Diant-aP ublication
SobeErl,l iott.
Untoo the:r tshee volutainodnp sycholoofgu yn selfbieshha viIo r
ElliSootbte Dra,v iSdl oaWni lson.
p. cm.
Inclubdiebsl iograrpehfiecraelan ncdei sn dex.
ISBN0 -674-930(4h6a-r0d cover)
1.A ltruis2m.H. e lpibnegh avio1r.W.i lsoDna,v iSdl oanI.I T.i tle.
BF637.H4S16959 8
171'.8-<1c21 97-42185
Acknowlgemdents
Maybiesr houclodma es snuor ptrhiawsteeh avree cesivome udc h
helipnw ritaib nogo k aboutW eaw latntrtout ihsamtn.hkf e o llow­
inbga ttaolfpi eoonp Tlhee.cy o me fmraonmdy i ffedriesncti plines
anhde lpienmd a ndyi ffewraeyRnsit: c hAalredx anAdnedrrA,er iew,
MartBianr rDeatnti,Be alt sJoonh,Bn e atLteynB, e rkowHiotwza,r d
BlooCmh,r iBso hmT,o mB ondDye,r iBco wndRso,b eBroty d,
RobeBrrta ndFoenl,Bi rxe dDeonn,C ampbNeolelCl,a rrAonlnle,
ClarRko,b ert CRoilcwhDeialevl i,d Jseofnf, DLeeaeDn ug,a tkin,
NancEyi senBbeerreEgnn,t� M ,u rvEent�T ,e Edv erReotbte,Fr rta nk,
Steve PFertaGenordk f,r ey-(Sofmrti httehi )dC,eh arGloeosd night,
LesGlriaev esG,r iJeismeD maevriG,du bernWiiclkl,Hi aammi lton,
HenrHya rpendDiannHg a,u smJaanc,Hk i rschHlaerimfoenr , Hol­
comIbI TIo,d Hdu gheRso,b eJreta nJnoeh,Kn e lBlryu,Kc nea uft,
HugLha FolAlnedtrtLeeew,v iJnoehM,na ynaSrmdi tRhi,cM ki chod,
DonM oskowGirtezg,o ry MougOirnz,a ScStktu,eaP vreetcn k , Jane
PiliaGvriePngo, l loWciklP,lr oviWniel,l iPaumkD aa,v iQdu eller,
H.K erRne eve, Peter RRiicshseTironsmgoS ,ne ,e lSetye,v eL arry
ShapAilraoSn,i deBlalreb,Sa mruat s, SDteanmnCpihesr, i s Stephens,
KimS tereWlinlyl,Ti aalmb oPtettT,ea ry lForra,dn esW aalM,i ke
Wade, DWeanlisDsho ,r Wiisl liGaemosr,Wg iel liEadmwsa,Wr idl ­
sonV,e rWoy nne-Edwards.
Wea lsmou setx teonudtr h antkoes n titthiaaetrsn e o itn dividuals;
perhtahpaisls si toso b ee xpecitnaeb do oakb omuutl tisleelveeclt ion
theoWreya .rg er atefsuulp pffoorrrotB m i nghaUmntiovne rtshiet y,
NatioSncaile Fnocuen daatnidot nh,e UniovfeW rissictoyn sin at
MadisFoinn.a wlelw ya,nt toa cknowltehsdeug pep aonrdetn cour­
agemetnhtah ta ve cformoem gtrwoou tphsaw tec ouanstn earest
anmdo sdte ar-fomauirl ies.
Contents
IntroidounBce:tn thCaomr'pss e 1
Par1Et. v uotlniaorAytl ruism 15
1A.l truaisas B mi oloCgoinccaelp t 17
2.A UnifiEevdo lutiTohneaoorrfSyy o cial Behavi5o5r
3.A daptaatniMdou nl tiSleelveeclt ion 101
4.G rouSpe lecatnido nH uBmeahna vior 123
5.H umaGnr oupAsd aapst Uinviet s 159
ParItIP .s yocolhgiAclatlr uism 197
6.M otiavsePs r oxiMmeacthe anisms 199
7.T hrTehee oroifMe ost ivation 223
8.P sycholEovgiidceanlc e 251
9.P hilosoAprhgiucmaeln ts 275
10T.h eE voluotfPi soync holAolgtircuails m 296
ConcluPsliuorna:l ism 329
Notes 339
References 363
Index 387
UntoO thers
d
IntroduBcetniotnh:a Cmo rpde
Them ummificeodr posfJe e reBmeyn thoacmc upaci aebsi tnheseti ze
ofa t elepbhooontienhU niveCroseilgtleLy,o ndoTnh.eh eawde nt
cheessoym tei maeg oa ndw asr eplabcyae wda xs ubstitthuet e;
origiisin naa lb oxt hastid tiss crbeeettwleByee nn thfaeme'Btse. n ­
thamw'isdl elc rteheahdti b so dwya s btepo r esearnvcdea dr ried into
meetionftg hsUe n iverBsoiatroydfT' rsu st(euRense1 s9 5p9.2, 5 0).
Benthtahmo ugthhtah ti sst ecronu natnecnweo ulidn spfiurteu re
generattoli iouvnpest ot hset andtahrahdtesa nd JohnM iSltlu art
advociantt hedet ihre oorfmy o ralaintpdyo liBteinctsh.aan mMd i ll
togetchreerat thepedh ilosoofup ithlayira tinsim-thvei etwh at peo­
ple sphrooumlotdth geer eahtaepspti fnoetrsh gser eantuemsbtoe fr
indiviBdeunatlhhsao.mp etdh aatm ummya ta m eetwionugl edn ­
courtahgoevs oet itnodg ot hrei gthhti ng.
Iti sa mattoefcr o njecjtuushrtoe wm ucihn fluBeenncteh am's
corphsaees x ercoivseUernd i verCsoiltliyen gt ehy ee asrisn hcies
deatbhu,it t i sa certatihnattthy ie d eas Benthahma vdee fended
profouanfdfleytc htweei dd ceurl tBuernet.h am tthhoaautlhg luh ­t
man activiatiymt oms ahxoiumlpidlz eea saunrdme i nimpiazien .
Underltyhicinlsga a ibmo wuhta t poeuogpthlodet o w asB entham's
pictoufhr oewt hheu man wmoirnkids n c tfAa.c cortdoiB negn tham
(1879)",na tuhraeps l acmeadn kiunndd etrhge o vernoaftn wcoe
sovermeaisgtnep rasia,nn dp lea.s"Bu ernethhaemr,ie se, n dorsing
1
2 Introduction Benmtd hC aorpde 3
psylcohgoihceadlo nistmh-etothrheyaa tv oidpianiagnn adt taining dos oi no rdteorf eeglo oadb otuhte msealnvdte oas v ofiede ling
pleasaurtrehe oe n luyl timmaotteit vheaspt e ophlaev eev;e rything guilEtgyo.i issam m ansiwointm ha nryo omTsh.e rsee emtsob e
eltsheaw tew anwte,w ansto laesla my e antsoa chietvhiontsgwe i n room eniontu hgtehh eotroye xplhaeilnp bienhga vainodtr h e
ends. existoefdn ecsei croensc ertnhiwene gl foafro et hebrost;ah r e ex­
Hedoniiasss mp ecviefircso ifaom no rgee netrhaelop rsyy,co hgoil­ plaiansei dn strufmoeprnr tosm otsienlgf -i2nA tsae rreessutl.t, the
caelg oiwshmi,cc hl aitmhsa t ienvdeiryv iudlutailmg'aostai els to concoefpa tl truisma nre enmdaainngssep reec(dia Cemsp b1e99ll4. )
benefito rhh iemr-sEeglofi.ms ami nttahiawnths e wne c araeb out Psycholeoggoiicisashml a rtdod isprbouvite ta, l siosh artdo
whahta ppetono st hewresd o,s oo nlaysa m eantsoi ncreoausri ng provEev.ei naf p urely esxepllfiasnchaa tbnie io mna gifnoeerdv ery
own welTfhaer evd.ie enwti hesa t peoplael tervuueilrst tihimacav tee acotf h elpitnhgid,so esmne'attn h aetg oiisscm o rrAefcttae.lr l ,
motivEegso.id somen so t wshaeyt whees rh ourledj ooirdc ees paati r humabne havailosirocs o nsiwsittethnh cteo ntrhayrpyo t-htehsaits
thfiesa touftr hehe u mamni nIdct.l aiomnslt yod eschroiwbt eh ings somoef o ur ulgtoiamaalrtsaee l truPissytcihco.l hoagvibese tesn
arien f acItn.a ll our sociwaela ridenr tievbreyaan s c itnigolnes , workionntg h pirso blfeodmre caadnepdsh ilosfoopcrhe enrtsu ries.
1
ques-t"iWohnati'nis ft o mre ?" Ther esuwlebt e,l iiesv eia,mn ps ase-tphreo bloefpm s ychological
Itw oulbded iffictoue lxta ggetrhapete er vaisnifvleu tehnacte egoiasnmda ltruriesmma iunnss olAv needw.a pproiasnc ehe ded.
hedonainsdem g oihsamv hea da ndc ontitnohu aev oen p eople's Then ovpeelr spetchtawitevw ei elxlp liospr reo vibdyte hdte h eory
thinkFionrmg a.n ye,g oism osbeveimoasu m sa,t toefcr o mmon ofe volution.
sense. aPreoeof ptulennes urpwrhiesne do tachwtei rtsrh u thless
selfishbnufietn sdsi t qrueimtaer kwahbelonet hesrasc rithfiecme­ Benthdaimei dn1 83m2o,r teh atnw od ecabdeefso rpeu ibtclhaet ion
selfvoers stahkoeefs omeoenlesI esf.o meosnaeyt sh ahtu man beings in1 589o fD arwiOnr'isgo ifSn p ecJioehsSn.t u aMritll li vweedl l
arbey n atusreel fipseho,pf lree qureengtaltryhd pi rso nnocuemeanst pastth iwsa tersehveednt th,o uhgehn evaecrc eptthetedh eory of
proceefdrioanmc g l earr-eeaylehidos wme;v er, isfa ytssho amte one evolutniaotnu srbeaylil eo .cnD3ta rwitnh'esog rayvr ei tsoea f unda­
humabne inagrsbe y n atubreen evopleeonptolf,et semni ilned ul­ mentpaulz zalbeo utthbe e havoifoo rrg aniTshmebs a.s iidceo af
genttlhyi,n ktihnagt the raesfslaeep rcrttoispo eynnt sovi itetwh e natusrealle citsi otcnhh aatr acteevroilbsveteci catsuh seehy e ltph e
world trhorsoeu-gchgo llaosrseeds . indiviwdhuopa olsss tehsestm o s urvivree parnoddA u hceer.d of
Whyd oepss ycholeoggoiihcsaamvl e asg urciohpn o usre lf-con­ zebrfaoer,x ampwlielg,lr aduianlclryie nar suen nsipnegbe edc ause
cept?iD ooneosu erv eryedxapye ripernocvei de ceovnicdleunsciev e fastzeerb rdaoas b ettere vajdopibrn egd atFoarsstz.ee rb raarse
thaitti st r?uH east hsec ieonfcp es ychodleomgoyn sttrhaatte d fittertheayrm eo raeb lteos urvainvtdee ntdoh ave omfofrsep ring
-
egoiisscm o rrHeacstp ?h ilos?A olptlhh yeqsuee stmiuosnbtse a n­ thasnl owoenre Isfo. f fsprreisnegmt bhlepeia rr etnhtfesr ,e quency
swerientd h nee gatoirsv oe ,ww iel l Tahreig nufel.u tehnapctse y cho­ off aszte b-rtahsep roporotfgi ooond ruinnn ethrheser d-will
logiecgaolie sxme rftaorsu treatcheheve isd enchea bste hemanut s ­ increNaosteit.ch eaa tz ebtrhaar tu nfsa sbte neifitts-sen lofott her
teroendi tbse half. zebrnaoslt,i onnostt,h weh oleec osysItnte hmie.sx ampnlaet,u ral
Egoiisesma seyn outgorh e fwuhteen i gsii tv aes ni mplfiosrtmiuc­ selecftaivootnrh sow sheo h eltph emseIlttvh eesr.ea fpopreeta hrast
latiFooner.x ampilfteh ,ee g oicslta itmhsat th e ounlltyi mgaotael helpoitnhgie nrd ivitdou asluasrn vdi vree partto hdeeux cpee onfs e
thapte ophlaevi ets o m aximtihzeeai crc etsocs o nsugmoeordi sit,s oneo'wsn s urvainvdar le produicst itohne vernya ttuhrianlg that
not htaodr eds crbeihbaev iosrhso twth hatatht ii ssfla sBeu.it tf h e selecwtiileolln i minastheo.rn ta,tI unsr ealle catpipoenta orb sea
egoissatyt sh ahtu man bsetirnifgvoseri nterpnsaylc,h ological proctehsapstr omosteelsfi sahnnsdet sasm opusat l truism.
benetfihtpesr ,o poishsaa lr dteopr r owvreo ng. pWehoepsnla ec rifice Darwina wwaarse otrhgaatn iinsn mast usroem etbiemhea ivne
theoiwrni ntetroeh setlsspo meoenlest ehe,eg omiasitn ttahitanhtse y waytsh aatp peaalrt ruFiosertx iacm.pa lh eo,n eysbaecer iifitlcseie fs
4 Introduction BentdhC aopmrtf e 5
fotrh ceo lownhye nu sieitst b sa rbsetdi ntgoae trt aicnkt rutdoe rs timeex plaitnheeiv nogl uotfci aomnflo augdei,s eraessei satanndc e,
thnee sAtn.dm anoyf t hmeo sptr aisewhourmtaqhnuy ia tlies-hon­ other atsir nadiitvsi duaadla-plteavBteiillooo ngsio.sf ttsse inm ply
estcyh,a rtirtuyas,nt dh,e roism-taopb peenaeorfit th eartes x pense chotshele e voefel x plantahtaito nt hemyo rifeno tuunidat pipveea,l ­
tos elDfa.r weixnp latihneesde charbaysc atyeitrnhigas tt incast ural intgoi ndivaiddaupatlao tnMi oonnd aWyesd,n esdaanyFdsr ,i days,
selecstoimoent iamcetossng roujpsusta, si tac tasto thteirm oens andt og rouapd aptaotnTi uoens dTahyusr,s daanydSs a,t urdays.
indiviAdnau latlrsmu.ai yhs atv fee woefrf sptrhiaannn g o naltruist Theoriwzaisun ngc onstraanidan deadp,t ateixopnliasntwa atsi on
withiitonsw ng roubpug,tr ouopfas l trwuiihlsaltv sme o roef fspring similuanrrleys trained.
than gorfon uopnsa ltIrnua if satmso.u s pfarsoTsmah gDee e scent Altlh cihsa ngientd h 1e69 0sw,h egnr ouspe lecwtaisao tnt acked
ofM anD,a rwuisne tdh per incoifgp rloeus pe lecttoei xopnl ain the bya n umboefrb ioloTghiesm tosst.th oroaungddh e vastcartii­ng
evoluotfhi uomna mno rality: tiqwuaes CG..W illia1m9s6'b6so okA,d aptaatnidNo ant ural
SelecWtiilolnit.ao musc hae nde rvaen,dh ivsi gorroeujse cotfi on
Itm usnto t fboerg otthtaaetln t hoauh gihgs ht andoafmr odr ality adaptatthiaoetnx sif sotr gtohoeod f t heg rouspp reqaudi ckly
givbeusat s glhiotr andov anttoae gaeci hn divmiadnu aahlni ds throtuhgeh commoufen viotlyu tionarFyo trbh ineoe lxotg idsetcs­.
chilodvreterhno e t hmeerno ft he starmiyebe ett,h aatni ncriena se adeg,r ouspe lectthieoownra ysw iderleyg aradse djn soutft a lbsuet
thneu mboefwr e ll-enmdeonaw neaddd vancientm hesent ta ndofa rd aso f-flimaisft asar,ss erieovuosl uttihoonuawgrahysct o ncerAnte d.
moraywl iictlelr tagiinvaleniy m menasdev anttoao ngteer iobvee r
besgtr,o audpa tpatwiaosn regaasart dheedo rpetoiscsaiblbu itl iatsy
anotThheercr.ae bn e n od oubt ttrhiiabntec lagu m dainmnye mbers
soe normouunslliytk healatyl terneaxtpilvaen asthioounlpsdr eb­e
whof,r opmo sseisnash iingdghe grtehseep iorfpi att rifiodteilsimt,y ,
ferrwehde nepvoesrs iTbhlefe o.l lopwaisngsge( a Ghise1l79i4n,
obediceonucrea,ag neds, y mpawtehryae,l waryesa tdoya iodn e
p.2 47i)ul sltrtahtfeee sr vwoirtw hh icahl trugirsotuipc-e,lx epvleal­
anotahnetdro s, a crtihfiecmes eltvheceso mfmoogrno owdo,u lbde
victoorviemorou ssot t hterri abnetdsh ;wi osu bledn atusrealle ction. natiwoenrrsee jeicnft aevdoo far c coutnhtaastp petaosl e lfishness:
Ata ltli mtehsr oughwoourttl rdti hhbeae vsseu pploatnhtteerrdi bes;
anadsm orailosin tieym portant tehleseiumrce cntehtsse sti ,an n dard Thee conoomfny a tuicrseo mpetfirtobimev gei ntnoi ne.gn. Tdh. e
ofm oralainttdyh n eu mboefrw ell-enmdeonww ietldhl u esv ery­ impultshealste aodn ae nimtaosl a crhiifimcsefe olarfn otthuerrn
whetreen tdor iasneid n cre(aDswaeir.1n 781p,.1 66) outto htahveueil rt irmaattieo innga aliena idnvga notvaeagtr e h ird
. .Wh.e rieit is n ohwinis n teerveesortry,g anmiasyrm e asonably
bee xpecttoae idhd i s f.e lYl.eo tw. s g aif vueclnhl a ntcoae c itn
AlthoDuagrhw nienv deir scuhsoswei dm portaa rnotlg er oup
hiosw ni nterestb,u etnx optehdiiwneignl rcley s thriamif rno m
selecptliaoyinent d hh ei stooflr iyf ep,r ahciwtsai tsco e apptehails to
brutalfirzomiman igm,i fnrgom,mu rderinbgr-ohtihhsiem sra ,t e,
procoenslrsya reDlayr.w isnu'csc essolresas bsws etreemi inovuosk,­
hipsa reonrt ,ch hiisSl cdr.a atnc" hat lruiasntwd,a "t cah" yhpo­
intgh per ocweisdse alnydo ftuennc ritAicccaolrldtyio.An lgl ee
cribtlee"e d.
(915,1 d)ominahniceer arecxhiitseotsm inimwiizteh in-group
conflsioc t,t hat gtrhoeu peb nectm aiornrpe er oducAtcicvoer.d ing Thei nterproefht uamtaibnoe nh avwiaosr similarlyI nt ransformed.
toW ynne-Ed(w9a16r2di)sn, d ivoirdguaanlri essmtstr haeimns elves TheB iloogoyfM oraSly steAmlesx,a n(d91e8,r7p .3 )s howtsh e
frocmo nsumfionoagdn fdr orme produscoti hnatgth,p e o pulation extetnowt h icbhi oloagbiadsnotnse tdh ied etah agte nuisneellfy­
cana voicdr ashtioen xgt incAtnidao cnc.o rtdoiD nogzb hansky sacribfiechiaavlai ropera sro tfo uerv olutlieognaacryy:
(9137w)h,o lsep ecmiaeisn tgaeinned tiivce rtsoci otpywe i tnhe w
environcmheanltlaelln igkseeas v;iv nyv estthoerdysi ,v eyr tshiefir Is usptehcantte arallhylu mabnesl iietiv saen ormalo ftp haer t
portfboelciaotushs feeu tuirsue n ceirnMt.aa ny biologists happilyf unctioofen vienhrguy m ainn divniodwau natdlh etnoa sssiosmte ­
invotkheedas nedo thgerro up-elxepvlealn awthiiaoltnet s hs ea me oneel steh reie na liozfa ttpiheoarnts oownn'i nst etroet shatecs t ual