### WhatShanlWeMam? # The Tragedy of the Commons ## Thepopulationproblemhasnotechnicalsolution; ## itrequiresafundamentalextensioninmorality. #### GarrettHardin ##### Attheendofathoughtfularticleon ##### thefutureofnuclearwar,Wiesnerand ##### York(1)concludedthat:"Bothsidesin #### thearmsraceare...confrontedbythe ##### dilemmaofsteadilyincreasingmilitary ##### powerandsteadilydecreasingnational ##### security. It is our considered profes- ##### sionaljudgmentthat thisdilemmahas ##### notechnicalsolution.Ifthegreatpow- ##### ers continue to look for solutions in ##### theareaofscienceandtechnologyonly, ##### theresultwillbetoworsenthesitua- ##### tion." ##### Iwouldliketofocusyourattention ##### noton the subjectofthe article (na- ##### tionalsecurityinanuclearworld)but ##### onthekindofconclusiontheyreached, ##### namelythatthereisnotechnicalsolu- ##### tion tothe problem. Animplicit and ##### almostuniversalassumption ofdiscus- ##### sions published in professional and ##### semipopular scientific journals is that ##### the problem under discussion has a ##### technicalsolution.Atechnicalsolution ##### maybedefinedasonethatrequiresa ##### changeonlyin.the techniques of the ##### natural sciences, demanding little or ##### nothinginthewayofchangeinhuman ##### valuesorideasofmorality. ##### In our day (though not in earlier ##### times) technical solutions are always ##### welcome. Becauseofpreviousfailures ##### inprophecy,ittakescourage toassert ##### thata desiredtechnicalsolutionisnot ##### possible. Wiesner and York exhibited ##### this courage; publishing in a science ##### journal, theyinsistedthatthesolution ##### totheproblemwasnottobefoundin ##### the natural sciences. They cautiously ##### qualified their statement with the ##### phrase, "It is our considered profes- Theauthorisprofessorofbiology,University of California, Santa Barbara. This article is basedonapresidentialaddresspresentedbefore themeetingofthePacificDivisionoftheAmeri- canAssociationfortheAdvancementofScience atUtahStateUniversity,Logan, 25 June1968. ``` 13 DECEMBER 1968 ``` ##### sional judgment.. .." Vhether they ##### wererightornotisnottheconcernof ##### thepresentarticle.Rather,theconcern ##### hereiswiththeimportantconceptofa ##### classofhumanproblemswhichcanbe #### called"notechnicalsolutionproblems," ##### and,morespecifically,withtheidentifi- ##### cationanddiscussionofone ofthese. ``` Itiseasytoshowthattheclassisnot a null class.Recall thegameoftick- ``` ##### tack-toe. Considertheproblem, "How ##### canIwin.the gameoftick-tack-toe?" ``` ItiswellknownthatIcannot,ifIas- ``` ##### sume(inkeepingwiththeconventions ``` ofgametheory)thatmyopponentun- ``` ##### derstandsthegame perfectly.Put an- ``` otherway,thereisno"technicalsolu- ``` ##### tion" totheproblem. Icanwinonly ##### bygivingaradicalmeaningtotheword ``` "win."Icanhitmyopponentoverthe ``` ##### head;orIcandrughim;orIcanfalsify ##### therecords.EverywayinwhichI"win" ##### involves, in somesense, an abandon- ##### mentofthegame,asweintuitivelyun- ##### derstand it. (I can also, of course, ##### openly abandon the game-refuse to ##### playit.Thisiswhatmostadultsdo.) ``` Theclassof"Notechnicalsolution ``` ##### problems" hasmembers. Mythesis is ##### thatthe"populationproblem,"ascon- ##### ventionallyconceived,isamemberof ##### thisclass.Howitisconventionallycon- ##### ceivedneedssomecomment. Itisfair ##### tosay thatmost people who'anguish ##### overthepopulationproblemaretrying ``` tofindawaytoavoidtheevilsofover- ``` ##### populationwithoutrelinquishinganyof ##### the privileges they now enjoy. They ##### thinkthatfarmingtheseasordevelop- ##### ingnewstrainsofwheatwillsolvethe #### problem-technologically.Itrytoshow ##### herethatthesolutiontheyseekcannot ##### befound.Thepopulationproblemcan- ##### notbesolvedin atechnicalway, any ##### morethancantheproblemofwinning ##### thegameoftick-tack-toe. ### Population,asMalthussaid,naturally #### tendstogrow"geometrically,"or,aswe #### would now say, exponentially. In a ##### finite world this means that the per ### capitashareoftheworld'sgoodsmust ### steadilydecrease.Isoursafiniteworld? #### Afairdefensecanbeputforwardfor ##### theviewthatthe worldis infinite; or ##### thatwedonotknowthatitisnot.But, #### intermsofthepracticalproblemsthat ##### wemustfaceinthenextfewgenera- #### tionswiththeforeseeabletechnology,it ### is clear thatwe will greatly increase ### humanmiseryifwedonot,duringthe #### immediatefuture,assumethattheworld ##### availabletotheterrestrialhumanpop- ### ulationis finite. "Space" isno escape ###### (2). #### A finite world can support only a ### finite population;therefore, population ### growthmusteventuallyequalzero.(The #### case of perpetual wide fluctuations ``` aboveandbelowzeroisatrivialvariant ``` #### thatneednotbediscussed.)Whenthis ##### conditionismet,whatwillbethesitua- #### tionofmankind?Specifically,canBen- ### tham's goalof"thegreatestgoodfor ##### the greatestnumber"be realized? ##### No-fortworeasons,eachsufficient #### byitself. Thefirstisatheoreticalone. #### It is not mathematically possible to #### maximizefortwo(ormore)variablesat #### thesametime.Thiswasclearlystated #### byvonNeumannandMorgenstern(3), ### buttheprincipleisimplicitinthetheory ### ofpartial differentialequations,dating ### back at least to D'Alembert (1717- #### 1783). ### The second reason springs directly #### from biological facts. To live, any #### organismmusthaveasourceofenergy #### (for example, food). This energy is ##### utilized fortwopuposes: meremain- ##### tenance and work. For man, mainte- nanceofliferequiresabout (^1600) kilo- ### caloriesaday("maintenancecalories'). #### Anythingthathedoesoverandabove #### merelystayingalivewill bedefinedas #### work,andissupportedby"workcal- ##### ories"whichhetakesin.Workcalories #### areusednotonlyforwhatwecallwork #### incommon speech; they arealsore- #### quiredforallformsofenjoyment,from ##### swimming and automobile racing to ##### playing music and writing poetry. If #### ourgoalistomaximizepopulationitis ##### obvious what we must do: We must ##### maketheworkcaloriesperpersonap- #### proachasclosetozeroaspossible.No ##### gourmetmeals,novacations,nosports, #### nomusic,noliterature, noart.. .. I #### thinkthateveryonewillgrant,without ``` 1243 ``` ``` on March 12, 2021^ ``` ``` http://science.sciencemag.org/ ``` ``` Downloaded from ``` ``` argument or proof, that maximizing ``` ##### population does not max2imize goods. ##### Bentham'sgoalisimpossible. ##### In reaching this conclusion I have ##### madethe usualassumption that it is ##### the acquisition of energy that is the ``` problem. The appearance of atomic energyhas led someto questionthis assumption.However,givenaninfinite source of energy, population growth ``` ##### stillproducesaninescapable problem. ##### Theproblemofthe acquisitionofen- ``` ergyisreplacedbytheproblemofits ``` ##### dissipation,asJ.H.Fremlinhassowit- ##### tilyshown(4).Thearithmeticsignsin ##### -t-heanalysis are,as itwere, reversed; ##### butBentham'sgoalisstillunobtainable. ``` Theoptimumpopulationis,then,less ``` ##### than the maximum. The difficulty of ##### definingtheoptimum isenormous;so ##### far asI know, no one has seriously ##### tackledthisproblem. Reaching anac- ##### ceptableandstablesolutionwillsurely ##### require more than one generation of ##### hardanalyticalwork-and muchper- ##### suasion. ##### We want the maximum good per ##### person;butwhatisgood?Tooneper- ##### sonitiswilderness,toanotheritisski #### lodgesforthousands.Tooneitisestu- ##### aries tonourish ducks forhunters to ##### shoot; to another it is factory land. ##### Comparingonegood withanother is, ##### we usually say, impossible because ##### goodsareincommensurable.Incommen- ##### surablescannotbecompared. ##### Theoreticallythismaybetrue;butin ##### reallifeincommensurablesarecommen- #### surable. Onlyacriterion ofjudgment ##### andasystemofweightingareneeded. ##### Innaturethecriterionissurvival.Isit ##### betterforaspeciestobesmallandhide- ##### able, orlarge and powerful? Natural ##### selectioncommensuratestheincommen- ##### surables.Thecompromiseachievedde- ##### pends on a natural weighting of the ##### valuesofthevariables. ##### Manmustimitatethisprocess.There ##### isnodoubtthatinfacthealreadydoes, ##### butunconsciously.Itiswhenthehidden ##### decisions are made explicit that the ##### argumentsbegin. Theproblem forthe ``` yearsaheadistoworkoutanaccept- ``` #### able theory of weighting. Synergistic ##### effects,nonlinearvariation,anddifficul- ##### tiesindiscountingthefuturemakethe #### intellectual problem difficult, but not ##### (inprinciple)insoluble. ##### Has any cultural group solved this ##### practical problem at thepresenttime, #### evenonanintuitivelevel?Onesimple ##### factprovesthat nonehas: thereisno ##### prosperouspopulationintheworldto- ##### day that has, and has had for some ``` 1244 ``` ``` time,-p -rateofzero.Anypeople ``` ##### that has intuitively identified itsopti- ##### mum point will soon reach it, after ##### whichitsgrowthratebecomesandre- ``` mainszero. ``` ##### Of course, a positive growth rate ##### mightbetakenasevidencethatapop- ##### ulationisbelowitsoptimum.However, ##### byany reasonablestandards,themost ##### rapidly growing populations on earth ``` todayare(ingeneral)themostmisera- ``` ##### ble.Thisassociation(whichneednotbe ##### invariable)castsdoubtontheoptimistic ``` assumptionthatthepositivegrowthrate ``` ##### ofapopulationisevidencethatithas ``` yettoreachitsoptimum. ``` ##### Wecanmakelittleprogressinwork- ##### ingtowardoptimumpoulationsizeuntil ``` we explicitly exorcize the spirit of ``` ##### Adam Smith inthe field ofpractical ##### demography.Ineconomic affairs, The ##### WealthofNations (1776) popularized ##### the "invisible hand,"the idea thatan ``` individual who "intendsonly hisown ``` ##### gain,"is,asitwere,"ledbyaninvisible ``` handtopromote..,.thepublicinterest" ``` ##### (5). Adam Smith did not assert that ##### this was invariablytrue, and perhaps ##### neitherdidanyofhisfollowers.Buthe ##### contributedtoadominanttendencyof ##### thoughtthat has eversinceinterfered ##### with positive action basedonrational ##### analysis, namely, the tendency to as- ##### sumethatdecisionsreachedindividually ##### will,infact,bethebestdecisionsforan ##### entire society. If this assumption is ##### correct it justifies the continuance of ##### our presentpolicy of laissez-faire in ##### reproduction.Ifitiscorrectwecanas- ``` sumethatmenwillcontroltheirindivid- ``` ##### ualfecunditysoastoproducetheopti- ##### mumpopulation. If theassumption is ##### notcorrect,weneedtoreexamineour ``` individualfreedoms toseewhichones aredefensible. ``` ##### TragedyofFreedominaCommons ``` Therebuttaltotheinvisiblehandin ``` ##### populationcontrolistobefoundina ##### scenariofirstsketchedinalittle-known ##### pamphlet(6)in 1833 byamathematical #### amateurnamedWilliamForsterLloyd ##### (1794-1852).Wemaywellcallit"the #### tragedy of the commons," using the #### word "tragedy" as the philosopher ##### Whiteheadusedit(7):"Theessenceof #### dramatictragedyisnotunhappiness.It #### residesinthesolemnityoftheremorse- #### lessworkingofthings."Hethen'goeson. ### tosay, "Thisinevitableness ofdestiny ##### canonlybeillustratedintermsofhu- ##### manlifebyincidentswhichinfactin- ##### volve unhappiness.For it is onlyby ##### themthatthefutilityofescapecanbe ##### madeevidentinthedrama." ##### Thetragedyofthecommonsdevelops ##### inthisway. Pictureapastureopento ##### all.Itistobeexpectedthateachherds- ##### manwilltrytokeepasmanycattleas ##### possibleonthecommons.Suchanar- ``` rangementmayworkreasonablysatis- ``` ##### factorily for centuries because tribal ##### wars, poaching, and disease keep the ##### numbers ofbothman andbeast well ##### belowthecarryingcapacityoftheland. ##### Finally, however, comes the day of ##### reckoning, that is, the day when the ##### long-desiredgoalofsocialstabilitybe- ``` comesareality. Atthispoint,thein- ``` ##### herentlogicofthecommonsremorse- ##### lesslygeneratestragedy. ##### Asa rationalbeing,eachherdsman ##### seekstomaximizehis gain.Explicitly ##### orimplicitly,moreorlessconsciously, ##### heasks,"Whatistheutilitytomeof ``` addingonemoreanimaltomyherd?" ``` ##### Thisutilityhas onenegative andone ##### positivecomponent. ``` 1)Thepositivecomponentisafunc- ``` ##### tionofthe increment ofone animal. ##### Since the herdsman receives all the ##### proceedsfromthesaleoftheadditional ##### animal,thepositiveutilityisnearly+1. ##### 2) Thenegativecomponentisafunc- ##### tion of the additional overgrazing ##### created by one more animal. Since, ##### however,theeffectsofovergrazingare ##### sharedbyalltheherdsmen,thenegative ##### utility for any particular decision- ##### makingherdsmanisonlyafractionof ##### -1. ##### Addingtogetherthecomponentpar- ##### tial utilities, the rational herdsman ##### concludesthattheonlysensiblecourse ``` forhim topursue is to add another ``` ##### animaltohis herd.And another;and ##### another....Butthisistheconclusion ##### reached by each and every rational ##### herdsmansharingacommons.Therein ##### isthetragedy.Eachmanislockedinto ##### asystemthatcompelshimtoincrease ##### hisherdwithoutlimit-inaworldthat ##### islimited. Ruin isthe destination to- ##### wardwhichallmenrush,eachpursuing ##### hisownbestinterest ina societythat ``` believes in the freedom of the com- ``` #### mons. Freedomina commons brings ##### ruintoall. #### Somewouldsaythatthisisaplati- ##### tude.Wouldthatitwere!Inasense,it ##### waslearnedthousandsofyearsago,but ##### natural selectionfavors the forces of #### psychologicaldenial(8).Theindividual #### benefitsasanindividualfromhisability #### todenythetrutheventhoughsocietyas ##### awhole,ofwhichheisapart,suffers. ``` SCIENCE,VOL. 162 ``` ``` on March 12, 2021^ ``` ``` http://science.sciencemag.org/ ``` ``` Downloaded from ``` ``` Education can counteract the natural ``` ##### tendencytodothewrongthing,butthe ##### inexorable succession of generations ##### requiresthatthebasisforthisknowl- ##### edgebeconstantlyrefreshed. ##### Asimpleincidentthatoccurredafew ##### yearsagoinLeominster,Massachusetts, ##### showshowperishabletheknowledgeis. ##### Duringthe Christmasshoppingseason ##### the parking meters downtown were ##### coveredwithplasticbagsthatboretags ##### reading:"DonotopenuntilafterChrist- ##### mas. Free parking courtesy of the ##### mayorandcitycouncil."Inotherwords, ##### facingtheprospectofanincreasedde- ##### mandforalreadyscarcespace,thecity ##### fathers reinstituted the system of the ##### commons. (Cynically, we suspect that ##### theygainedmorevotesthan theylost ##### bythisretrogressiveact.) ##### Inanapproximateway,thelogicof ##### thecommonshasbeenunderstoodfor ##### a long time, perhaps since the dis- ##### coveryofagricultureorthe invention ##### ofprivateproperty inreal estate. But ##### itisunderstoodmostly onlyinspecial ##### caseswhicharenotsufficientlygeneral- ##### ized.Even atthislate date,cattlemen ##### leasing national land on the western ##### ranges demonstrate no morethan an ##### ambivalentunderstanding,inconstantly ##### pressuringfederalauthoritiestoincrease ##### theheadcounttothepointwhereover- ##### grazing produces erosion and weed- ##### dominance.Likewise,theoceansofthe ##### worldcontinuetosufferfromthe sur- ##### vivalofthephilosophyofthecommons. ##### Maritimenationsstillrespondautomat- ##### icallytotheshibbolethofthe"freedom ##### ofthe seas." Professing tobelieve in ##### the "inexhaustible resources of the ##### oceans,"theybringspeciesafterspecies ##### offishandwhalesclosertoextinction ### (9). ##### TheNationalParkspresentanother ##### instance of the working out of the ##### tragedy ofthe commons.At present, ##### theyareopentoall,withoutlimit.The ##### parksthemselvesarelimitedinextent- ##### there is onlyone Yosemite Valley- ##### whereaspopulationseemstogrowwith- ##### outlimit.Thevaluesthatvisitors seek ##### intheparksaresteadilyeroded.Plainly, ``` wemustsoon ceasetotreattheparks ``` ##### ascommonsortheywillbeofnovalue toanyone. ##### Whatshallwedo?Wehaveseveral ##### options.Wemightsellthemoffaspri- ##### vateproperty.Wemightkeepthemas ##### public property,but allocate theright #### toenterthem.Theallocationmightbe ##### onthebasisofwealth,bytheuseofan ##### auctionsystem.Itmightbeonthebasis #### ofmerit, as defined by some agreed- ``` 13 DECEMBER 1968 ``` ##### uponstandards.Itmightbebylottery. ##### Or itmight be on a first-come, first- ##### served basis, administered to long ##### queues. These, I think, are all the ##### reasonable possibilities. They are all ##### objectionable.Butwemustchoose-or ##### acquiesceinthedestructionofthecom- ``` monsthatwecallourNationalParks. ``` ``` Pollution ``` ##### In a reverse way, the tragedy of ##### thecommonsreappearsinproblemsof ##### pollution.Hereitisnotaquestion of ##### takingsomethingoutofthecommons, #### but of putting something in-sewage, ##### or chemical, radioactive, and heat ##### wastesintowater;noxiousanddanger- ##### ousfumesintotheair;anddistracting ##### and unpleasant advertising signs into ##### the line of sight. Thecalculations of ##### utility are much the same as before. ``` Therationalmanfindsthathisshareof ``` ##### thecostofthewasteshedischargesinto ``` the commons islessthan the costof ``` ##### purifying his wastes before releasing ``` them.Sincethisistrueforeveryone,we ``` ##### arelockedintoasystemof"foulingour ##### ownnest," solongaswebehaveonly ##### as independent, rational, free-enter- ``` prisers. ``` ##### The tragedyof the commons as a ``` foodbasketisavertedbyprivateprop- ``` ##### erty,orsomethingformallylikeit.But ##### theairandwaterssurroundinguscan- ##### notreadilybefenced,andsothetrag- ##### edyofthecommonsasacesspoolmust ##### bepreventedbydifferentmeans,byco- ##### ercivelawsortaxingdevicesthatmake ##### itcheaperforthepollutertotreat his ##### pollutantsthanto discharge themun- ``` treated.Wehavenotprogressedasfar ``` ##### withthesolutionofthisproblemaswe ##### havewiththefirst.Indeed,ourparticu- ##### larconceptofprivateproperty,which ##### deters usfrom exhaustingthepositive ##### resourcesoftheearth,favorspollution. ##### Theownerofafactoryonthebankof ##### a stream-whose property extends to ##### the middle of the stream-often has ##### difficultyseeingwhyitisnothisnatural ##### righttomuddythewatersflowingpast ##### hisdoor.The law, alwaysbehindthe ##### times,requires elaborate stitchingand ##### fittingtoadaptittothisnewlyperceived ##### aspectofthecommons. ##### The pollution problem is a con- ##### sequenceofpopulation.Itdidnotmuch ##### matterhowalonelyAmericanfrontiers- ##### man disposed ofhis waste. "Flowing ##### waterpurifiesitselfevery 10 miles,"my ##### grandfatherusedtosay,andthemyth ``` wasnearenoughtothetruthwhenhe ``` ### wasaboy,fortherewerenottoomany ## people.Butaspopulationbecamedenser, #### thenaturalchemicalandbiologicalre- ### cycling processes became overloaded, ### calling for a redefinition of property ## rights. ### HowTo LegislateTemperance? ### Analysisofthepollutionproblemas ### a function of population density un- ### coversanotgenerallyrecognizedprin- ## cipleofmorality,namely: themorality ### ofanactisafunctionofthestateof ### thesystematthetimeitisperformed ### (10).Usingthecommonsasacesspool #### doesnotharmthegeneralpublicunder #### frontierconditions,becausethereisno ### public;thesamebehaviorinametropo- #### lisisunbearable.A hundredandfifty #### years ago a plainsman could kill an #### Americanbison,cutoutonlythetongue #### forhisdinner,anddiscardtherestof ### theanimal.Hewasnotin anyimpor- ### tantsensebeingwasteful.Today,with #### only a few thousand bison left, we #### wouldbeappalledatsuchbehavior. #### Inpassing,itisworthnotingthatthe #### moralityofanactcannotbedetermined #### fromaphotograph.Onedoesnotknow #### whether amankilling anelephant or ### settingflretothegrasslandisharming ##### othersuntiloneknowsthetotalsystem ### inwhichhisactappears."Onepicture #### is worth a thousand words," said an #### ancientChinese;butitmaytake10, #### wordstovalidateit.Itisastemptingto #### ecologistsasitistoreformersingeneral #### totrytopersuadeothersbywayofthe #### photographicshortcut.Butthe essense #### of an argument cannot be photo- #### graphed:itmustbepresentedrationally ##### -inwords. #### That morality is system-sensitive #### escapedtheattentionofmostcodifiers ##### of ethics in the past. "Thou shalt ##### not.. ." is the form of traditional ##### ethicaldirectiveswhichmakenoallow- #### anceforparticularcircumstances. The #### lawsofoursocietyfollowthepatternof #### ancientethics,andthereforearepoorly #### suitedtogoverningacomplex,crowded, #### changeable world. Ourepicyclic solu- ##### tion istoaugment statutorylaw with ##### administrativelaw.Sinceitispractically #### impossibletospelloutalltheconditions ##### underwhichitissafetoburntrashin ##### thebackyardortorunanautomobile ##### withoutsmog-control, bylawwe dele- ##### gatethe detailstobureaus.Theresult ##### isadministrative law, whichis rightly #### feared for an ancient reason-Quis ##### custodiet ipsos custodes?-"Who shall ``` 1245 -A ``` ``` on March 12, 2021^ ``` ``` http://science.sciencemag.org/ ``` ``` Downloaded from ``` ##### watchthe watchersthemselves?" John ##### Adamssaidthatwemusthave"agov- ##### ernmentoflawsandnotmen."Bureau ``` administrators, trying to evaluate the moralityofactsinthetotalsystem,are ``` ##### singularlyliable tocorruption, produc- ##### ingagovernmentbymen,notlaws. ``` Prohibition is easy to legislate ``` ##### (thoughnotnecessarilytoenforce);but ##### howdo welegislate temperance? Ex- ##### perience indicates that it can be ac- complishedbestthrough themediation ofadministrative law. Welimit possi- ##### bilitiesunnecessarilyifwesupposethat ##### thesentimentof Quiscustodietdenies us the useofadministrative law. We should rather retain the phrase as a perpetual reminder offearful dangers we cannotavoid. The great challenge ##### facingusnowistoinventthecorrective ##### feedbacksthatareneededtokeepcus- ##### todians honest.We mustfindways to ##### legitimatetheneededauthorityofboth thecustodiansandthecorrectivefeed- ##### backs. ##### Freedom To Breed Is Intolerable ##### Thetragedyofthe commons isin- ##### volved in population problems inan- ##### otherway. Inaworldgovernedsolely ##### by theprincipleof"dog eatdog"-if ##### indeedthereeverwassuchaworld- ##### howmanychildrenafamilyhadwould ##### not be a matter of public concern. ##### Parentswhobredtooexuberantlywould ##### leavefewerdescendants,notmore,be- ##### cause they would be unable to care ##### adequately for their children. David ##### Lackandothershavefoundthatsucha ##### negative feedback demonstrably con- ##### trols the fecundity ofbirds (11). But ##### menarenotbirds,andhavenotacted ##### likethemformillenniums,atleast. ##### If eachhumanfamily weredepen- ##### dentonlyonitsownresources;ifthe ##### childrenofimprovidentparentsstarved ##### todeath;if,thus,overbreedingbrought ##### itsown"punishment"tothegermline- ##### thentherewouldbenopublic interest ##### incontrollingthebreedingoffamilies. ##### Butoursocietyisdeeplycommittedto ##### thewelfare state (12), and hence is ##### confrontedwithanotheraspectofthe ##### tragedyofthecommons. ##### Inawelfarestate,howshallwedeal ##### withthefamily,thereligion, therace, #### ortheclass(orindeedanydistinguish- #### able and cohesive group) that adopts ##### overbreeding asa policyto secureits #### own aggrandizement (13)? To couple ##### the conceptoffreedomtobreedwith ##### the belief that everyone born has an ``` 1246 ``` ``` equalrighttothecommonsistolock theworldintoatragiccourseofaction. Unfortunatelythisisjustthecourse ofactionthatisbeingpursued bythe UnitedNations.Inlate1967,some 30 nationsagreedtothefollowing(14): The Universal Declaration of Human Rightsdescribesthefamilyasthenatural and fundamental unit ofsociety. Itfol- lows that anychoice and decision with regardtothesizeofthefamilymustirte- vocably rest with the family itself, and cannot bemadebyanyoneelse. Itispainfultohavetodenycategor- icallythevalidityofthisright;denying ``` ##### it,onefeelsasuncomfortableasaresi- ##### dent of Salem, Massachusetts, who ``` deniedtherealityofwitchesinthe17th century.Atthepresenttime,inliberal quarters,somethinglikeatabooactsto ``` ##### inhibitcriticismoftheUnitedNations. ##### There is a feeling that the United ``` Nations is "our last and best hope," ``` ##### thatweshouldn'tfindfaultwithit;we ##### shouldn't play into the hands of the ``` archconservatives. However,letusnot ``` ##### forget what Robert Louis Stevenson ##### said: "Thetruththatissuppressedby ##### friends isthe readiest weapon ofthe ##### enemy."Ifwelovethetruthwemust ##### openlydenythevalidityoftheUniversal ##### Declaration of Human Rights, even ##### thoughit is promoted bythe United ##### Nations. We should also join with ##### Kingsley Davis (15) inattemptingto ##### getPlannedParenthood-WorldPopula- ##### tiontoseetheerrorofitswaysinem- ##### bracingthesametragicideal. ##### ConscienceIsSelf-Eliminating ##### Itisamistaketothinkthatwecan ##### controlthebreedingofmankindinthe ##### long run byan appealtoconscience. ##### CharlesGaltonDarwinmadethispoint ##### whenhespokeonthecentennialofthe ##### publication of his grandfather's great ##### book. The argumentisstraightforward ##### andDarwinian. ##### Peoplevary.Confrontedwithappeals #### tolimitbreeding,somepeoplewillun- #### doubtedly respond to the plea more ``` than others. Those who have more ``` ##### childrenwillproduce alargerfraction ##### ofthenextgenerationthanthosewith ##### moresusceptibleconsciences. Thedif- #### ferencewillbeaccentuated, generation ##### bygeneration. ##### InC. G. Darwin'swords: "It may ##### wellbethatitwouldtakehundredsof #### generationsfortheprogenitive instinct ##### todevelopinthisway,butifitshould ``` do so, nature would have taken her ``` #### revenge,andthevarietyHomocontra- ##### cipiens would become extinct and ##### wouldbereplacedbythevarietyHomo ##### progenitivus" (16). ##### The argument assumes that con- ##### scienceor thedesire forchildren (no ##### matterwhich)ishereditary-butheredi- ##### tary only in the most general formal ``` sense. The result will be the same ``` ##### whether the attitude is transmitted ##### throughgerm cells, orexosomatically, ##### touseA.J.Lotka'sterm.(Ifonedenies ``` the latter possibility as well as the ``` ##### former,thenwhat'sthepointofeduca- ##### tion?) The argument has here been ##### statedinthecontextofthepopulation ``` problem,butitapplies equallywellto ``` ##### any instance in whichsociety appeals ``` toanindividualexploitingacommons to restrain himself for the general ``` ##### good-bymeansofhisconscience.To ##### make such anappeal is to set up a ``` selectivesystemthatworkstowardthe eliminationofconsciencefromtherace. ``` ##### PathogenicEffectsofConscience ##### The long-term disadvantage of an ##### appealtoconscience shouldbeenough ``` tocondemn it; but hasserious short- ``` ##### term disadvantagesaswell. Ifwe ask ##### amanwhoisexploitingacommonsto ##### desist "in the name of conscience," ##### whatarewesayingtohim?Whatdoes ##### hehear?-notonlyatthemomentbut ``` also in the wee small hours of the ``` ##### nightwhen, halfasleep,heremembers ``` notmerelythewordsweusedbutalso the nonverbalcommunication cueswe gave him unawares? Sooner or later, ``` ##### consciouslyorsubconsciously,hesenses ``` thathehas received two communica- ``` ##### tions,andthattheyarecontradictory: ##### (i) (intendedcommunication) "Ifyou ##### don'tdoasweask,wewillopenlycon- ##### demnyoufornotactinglikearespon- ##### sible citizen"; (ii) (the unintended ##### communication) "Ifyoudobehaveas ##### weask,wewillsecretlycondemr.you ##### for a simpleton who can be shamed ##### intostandingasidewhiletherestofus ##### exploitthecommons." ##### Everyman then is caught in what ``` Bateson has called a "double bind." Batesonandhisco-workershavemade ``` ##### aplausiblecaseforviewingthedouble ##### bindasanimportantcausativefactorin ##### the genesisofschizophrenia(17).The ##### double bind may not always be so #### damaging,butitalwaysendangersthe ``` mentalhealthofanyonetowhomitis ``` ##### applied. "A bad conscience," said ##### Nietzsche,"isakindofillness." ##### Toconjureupaconscienceinothers ``` SCIENCE,VOL. 162 ``` ``` on March 12, 2021^ ``` ``` http://science.sciencemag.org/ ``` ``` Downloaded from ``` ##### istempting toanyonewho wishes to ##### extend his control beyond the legal #### limits. Leaders at the highest level ##### succumb to this temptation. Hasany ##### President during the past generation ##### failedtocallonlaborunionstomoder- ##### atevoluntarilytheirdemandsforhigher ##### wages,ortosteelcompaniestohonor ##### voluntary guidelines on prices?I can ##### recallnone.Therhetoricusedonsuch ##### occasionsis designedtoproducefeel- ##### ingsofguiltinnoncooperators. ##### Forcenturiesitwasassumedwithout ##### proofthatguiltwasavaluable,perhaps ##### evenanindispensable,ingredientofthe ##### civilizedlife.Now,inthispost-Freudian ``` world,wedoubtit. Paul Goodman speaks from the modern point ofview when he says: ``` ##### "Nogood hasevercome fromfeeling ##### guilty, neither intelligence,policy, nor ##### compassion. The guilty do not pay ##### attentiontotheobjectbutonlytothem- ##### selves, and noteven totheirown in- ##### terests,whichmightmakesense,butto ##### theiranxieties" (18). ##### Onedoes nothavetobe a profes- ##### sional psychiatrist to see the conse- ##### quencesofanxiety.WeintheWestern ##### worldarejustemergingfromadreadful ##### two-centuries-long DarkAgesofEros ##### that was sustained partly by prohibi- ##### tionlaws,butperhapsmoreeffectively ##### by the anxiety-generating mechanisms ``` ofeducation.AlexComforthastoldthe ``` ##### storywellinTheAnxietyMakers(19); ``` itisnotaprettyone. ``` ##### Sinceproofisdifficult,wemayeven ##### concedethattheresultsofanxietymay ##### sometimes,fromcertainpointsofview, ##### be desirable. The larger question we ##### should askiswhether, asa matterof ##### policy, we should everencourage the ``` useofatechniquethetendency(ifnot ``` ##### the intention) of whichispsycholog- ##### ically pathogenic. Wehearmuchtalk ##### these daysofresponsible parenthood; ##### the coupled words are incorporated ##### intothetitlesofsomeorganizationsde- ``` voted to birth control. Some people ``` ##### have proposed massive propaganda #### campaigns to instillresponsibility into ##### thenation's (ortheworld's) breeders. ##### Butwhat isthemeaning ofthe word ##### responsibilityinthis context?Isitnot ##### merelya synonym for theword con- ##### science? When we use the word re- ``` sponsibilityintheabsenceofsubstantial ``` ##### sanctionsarewenottryingtobrowbeat a freemaninacommonsintoacting ##### againsthisowninterest?Responsibility ##### isaverbalcounterfeitforasubstantial ##### quidproquo. Itisan attempt toget ##### somethingfornothing. ``` 13 DECEMBER 1968 ``` ##### If the word responsibility is to be ##### usedatall,Isuggestthatit beinthe ``` sense Charles Frankel uses it (20). ``` #### "Responsibility," saysthisphilosopher, ##### "is the product of definite social ar- ##### rangements."Notice thatFrankelcalls ##### for social arrangements-not propa- #### ganda. ``` MutualCoercion ``` ##### MutuallyAgreedupon #### Thesocialarrangementsthatproduce ##### responsibility are arrangements that ##### createcoercion, of somesort. Consid- ##### er bank-robbing. The man whotakes ``` moneyfromabankactsasifthebank ``` ##### wereacommons.How doweprevent ##### suchaction?Certainlynotbytryingto ##### controlhisbehaviorsolelybyaverbal ##### appeal to his sense of responsibility. ##### Rather than rely on propaganda we ``` followFrankel'sleadandinsistthata bank isnot a commons; we seek the definite social arrangements that will ``` ##### keep it from becoming a commons. ##### Thatwetherebyinfringeon thefree- ``` dom of would-be robbers we neither ``` ##### denynorregret. ##### The morality of bank-robbing is ##### particularlyeasytounderstandbecause ##### weacceptcompleteprohibitionofthis ##### activity. We arewillingto say"Thou ##### shaltnotrobbanks,"withoutproviding ``` forexceptions.Buttemperancealsocan ``` ##### becreatedbycoercion.Taxingisagood ##### coercive device. To keep downtown ##### shoppers temperate in their use of ##### parking space we introduce parking ##### meters for short periods, and traffic ##### fines for longer ones. We need not ##### actuallyforbidacitizentoparkaslong ``` ashewantsto;weneedmerelymakeit ``` ##### increasinglyexpensiveforhimtodoso. ##### Not prohibition, but carefully biased ##### optionsarewhatweofferhim.AMadi- ##### son Avenue man might callthisper- ##### suasion;Ipreferthegreatercandorof ``` theword coercion. ``` ##### Coercion is a dirty word to most ##### liberalsnow,butitneednotforeverbe ##### so. As withthe four-letter words, its ##### dirtiness canbecleansed awayby ex- ##### posuretothelight,bysayingitoverand ##### overwithoutapologyorembarrassment. ``` To many, the word coercion implies ``` ##### arbitrarydecisionsofdistantandirre- ##### sponsiblebureaucrats;butthisisnota ``` necessarypartofitsmeaning.Theonly ``` ##### kindofcoercionIrecommendismutual ##### coercion,mutuallyagreeduponbythe ##### majorityofthepeopleaffected. ``` Tosay that we mutually agree to ``` ##### coercionisnottosaythatwearere- #### quiredtoenjoyit,oreventopretend #### weenjoyit.Whoenjoystaxes?Weall #### grumble about them. But we accept ### compulsorytaxesbecausewerecognize ### that voluntary taxes would favor the #### conscienceless.Weinstituteand(grum- #### blingly)supporttaxesandothercoercive ##### devices to escape the horror of the ``` commons. ``` ##### Analternativetothecommonsneed ### notbeperfectlyjust tobe preferable. ``` With real estate and other material ``` #### goods, thealternative wehavechosen #### is the institution of private property #### coupled withlegal inheritance. Isthis ### systemperfectlyjust?Asa genetically ### trained biologist I deny that it is. It #### seemstomethat,iftherearetobedif- #### ferencesinindividualinheritance,legal #### possession should be perfectly cor- #### relatedwithbiologicalinheritance-that #### thosewhoarebiologicallymorefit to ``` bethecustodiansofpropertyandpower ``` ### shouldlegallyinheritmore.Butgenetic #### recombination continually makes a #### mockeryofthedoctrineof"likefather, #### likeson"implicitinourlawsoflegalin- #### heritance.Anidiotcaninheritmillions, ##### anda trust fund can keephis estate ### intact. We mustadmit thatour legal #### systemofprivateproperty plusinheri- #### tanceisunjust-butweputupwithit #### becausewe are notconvinced, atthe ##### moment, that anyone has invented a ##### better system. The alternative of the #### commonsistoohorrifyingtocontem- ##### plate. Injustice is preferable to total ``` ruin. ``` ##### Itisoneofthe peculiaritiesofthe ##### warfarebetweenreformandthestatus ##### quo that it is thoughtlessly governed ##### byadoublestandard.Wheneverare- ##### formmeasure is proposedit is often ##### defeated when its opponents trium- #### phantlydiscoveraflawinit.AsKings- #### leyDavishaspointedout(21),worship- ##### persofthestatusquosometimesimply ##### thatnoreformispossiblewithoutunan- ##### imous agreement, animplication con- ##### trarytohistoricalfact.AsnearlyasI ##### canmake out, automaticrejection of ##### proposedreformsis based on oneof ##### twounconscious assumptions: (i) that ##### thestatusquoisperfect;or(ii)thatthe ##### choicewefaceisbetweenreformand ##### no action; if theproposed reform is ##### imperfect,we presumablyshould take ##### noaction atall, while wewait fora ##### perfectproposal. ##### Butwecanneverdonothing.That ##### whichwehavedonefor thousandsof ##### years is also action. Italso produces ##### evils. Once we are aware that the ``` 1247 ``` ``` on March 12, 2021^ ``` ``` http://science.sciencemag.org/ ``` ``` Downloaded from ``` ``` statusquoisaction,wecanthencom- ``` ##### pare its discoverable advantages and ##### disadvantages with the predicted ad- ##### vantagesanddisadvantagesofthepro- ##### posed reform, discounting as bestwe ##### canforourlackofexperience.Onthe ##### basis of such a comparison, we can ##### makearationaldecisionwhichwillnot ##### involvetheunworkableassumptionthat onlyperfectsystemsaretolerable. ##### RecognitionofNecessity ``` Perhapsthesimplestsummaryofthis ``` ##### analysis ofman'spopulation problems ##### isthis: the commons, if justifiable at ##### all,isjustifiable onlyunderconditions ##### oflow-population density. As thehu- ##### man population has increased, the ##### commonshashadtobeabandonedin oneaspectafteranother. ##### Firstweabandonedthecommonsin ##### food gathering, enclosing farm land ##### and restricting pastures and hunting ##### and fishing areas. These restrictions ##### are still not complete throughout the ##### world. ##### Somewhatlaterwesawthatthecom- ##### mons as a place for waste disposal ##### wouldalsohavetobeabandoned. Re- ##### strictions onthe disposalof domestic ##### sewage are widely accepted in the #### Westernworld;weare stillstruggling ##### toclosethecommons topollutionby ##### automobiles, factories, insecticide #### sprayers, fertilizing operations, and ##### atomicenergyinstallations. ##### Inastillmoreembryonicstateisour ##### recognitionoftheevilsofthecommons #### inmattersofpleasure.Thereisalmost ##### no restriction on the propagation of #### soundwavesinthepublicmedium.The ##### shoppingpublicisassaultedwithmind- #### less music, without its consent. Our ##### government is paying out billions of ##### dollars to create supersonic transport ##### which will disturb 50,000 people for ``` everyonepersonwhoiswhiskedfrom coast to coast 3 hours faster. Adver- ``` ##### tisersmuddytheairwavesofradioand ##### television and pollute the view of ``` travelers.Wearealongwayfromout- ``` ##### lawing the commons in matters of ``` pleasure. Is this because our Puritan ``` ##### inheritance makesusview pleasureas ``` somethingofa sin,andpain (thatis, ``` ##### thepollutionofadvertising)asthesign ##### ofvirtue? ``` Every new enclosure of the com- ``` ##### mons involves the infringement of ##### somebody's personal liberty. Infringe- ##### mentsmadeinthedistantpastareac- ##### cepted becausenocontemporary com- ``` plainsof a loss. It isthe newlypro- ``` ##### posedinfringementsthatwevigorously ##### oppose;criesof"rights"and"freedom" ##### fillthe air.But whatdoes "freedom" ##### mean?Whenmen mutually agreedto ##### passlawsagainstrobbing,mankindbe- ##### camemorefree,notlessso.Individuals ##### lockedinto thelogicofthe commons ##### arefreeonlytobringonuniversalruin; ##### once theyseethe necessityofmutual ##### coercion, they become free to pursue ##### othergoals.IbelieveitwasHegelwho ##### said, "Freedom is the recognition of ##### necessity." ##### Themostimportantaspectofneces- ##### sitythatwemustnowrecognize,isthe #### necessityof abandoning the commons ##### inbreeding. Notechnicalsolutioncan ##### rescueusfromthemiseryofoverpopu- #### lation. Freedom to breed will bring ##### ruin to all.At the moment,to avoid #### harddecisionsmanyofusaretempted ##### to propagandize for conscience and #### responsible parenthood. The tempta- ##### tion mustbe resisted,because an ap- ##### peal to independently acting con- ##### sciences selects for the disappearance ##### ofallconscienceinthelongrun,and #### anin,creaseinanxietyintheshort. ``` Theonlywaywe canpreserveand nurtureotherandmore preciousfree- ``` ##### doms is byrelinquishingthe freedom ##### tobreed,andthatverysoon."Freedom ##### istherecognitionofnecessity"-andit ##### istheroleofeducationtorevealtoall ##### the necessity of abandoning the free- #### domtobreed.Onlyso,canweputan ##### endtothisaspectofthetragedyofthe ``` commons. ``` ``` References 1.J.B. WiesnerandH. F.York,Sci.Amer. 211 (No.4),^27 (1964). 2.G.Hardin,J.Hered.50,^68 (1959);S.von Hoernor,Science137, 18 (1962). 3.J.vonNeumannand0.Morgenstern,Theory ofGamesandEconomicBehavior(Princeton Univ.Press,Princeton,N.J.,1947),p.11. 4.J.H.Fremlin,NewSci.,No. 415 (1964),p.285. 5.A. Smith, The WealthofNations (Modem Library,NewYork,1937),p.423. 6.W.F.Lloyd,TwoLecturesontheChecksto Population(OxfordUniv.Press,Oxford,Eng- land,1833),reprinted(inpart>inPopulation, Evolution, and Birth Control, G. Hardin, Ed. (Freeman,SanFrancisco,1964),p.37. 7.A.N. Whitehead, Science andtheModern World(Mentor,NewYork,1948),p.17. 8.G. Hardin,Ed. Population, Evolution,and BirthControl(Freeman,SanFrancisco,1964), p.56. 9.S.McVay,Sci.Amer.^216 (No.8>,^13 (1966). 10.J. Fletcher, Situation Ethics (Westminster, Philadelphia, 1966). 11.D.Lack,TheNaturalRegulation ofAnimal Nuimbers (Clarendon Press, Oxford, 1954). 12.H. Girvetz,FromWealthto Welfare(Stan- fordUniv.Press,Stanford, Calif.,1950). 13.G.Hardin,Perspec.Biol.Med.6,^366 (1963). 14.U.Thant,Int.PlannedParenthoodNews,No. 168 (February1968>,p.3. 15.K. Davis,Science158, 730 (1967). 16.S. 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Science 162 (3859), 1243-1248. ``` ARTICLE TOOLS http://science.sciencemag.org/content/162/3859/ ``` ``` REFERENCES http://science.sciencemag.org/content/162/3859/1243#BIBL ``` ``` This article cites 11 articles, 2 of which you can access for free ``` ``` PERMISSIONS http://www.sciencemag.org/help/reprints-and-permissions ``` Use of this article is subject to the Terms of Service trademark of AAAS. Advancement of Science, 1200 New York Avenue NW, Washington, DC 20005. The title Science is a registered Science (print ISSN 0036-8075; online ISSN 1095-9203) is published by the American Association for the of Science. No claim to original U.S. Government Works. Copyright © 1968 The Authors, some rights reserved; exclusive licensee American Association for the Advancement ``` on March 12, 2021^ ``` ``` http://science.sciencemag.org/ ``` ``` Downloaded from ```