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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

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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

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

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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

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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

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

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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,

rangements."Notice thatFrankelcalls

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

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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-

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. Tax,Ed.,EvolutionafterDarwin(Univ.
ofChicagoPress,Chicago,1960),vol.2,p.
469.
17.G.Bateson,D.D.Jackson,J.Haley,J.Weak-
land,Behav.Scd.1,^251 (1956).
18.P.Goodman,New York Rev.Books 10(8),
22 (23May1968).
19.A. Comfort, The Anxiety Makers (Nelson,
London,1967).
20.C.Frankel,TheCaseforModernMan(Har-
per,NewYork,1955),p.203.
21.J.D.Roslansky,GeneticsandtheFutureof
Man (Appleton-Century-Crofts, New York,
1966),p.177.

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The Tragedy of the Commons

Garrett Hardin

DOI: 10.1126/science.162.3859.

Science 162 (3859), 1243-1248.

ARTICLE TOOLS http://science.sciencemag.org/content/162/3859/

REFERENCES
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43 KiB Raw Blame History

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-

sional judgment.. .." Vhether they

wererightornotisnottheconcernof

thepresentarticle.Rather,theconcern

hereiswiththeimportantconceptofa

classofhumanproblemswhichcanbe

called"notechnicalsolutionproblems,"

and,morespecifically,withtheidentifi-

cationanddiscussionofone ofthese.

tack-toe. Considertheproblem, "How

canIwin.the gameoftick-tack-toe?"

sume(inkeepingwiththeconventions

derstandsthegame perfectly.Put an-

tion" totheproblem. Icanwinonly

bygivingaradicalmeaningtotheword

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.)

problems" hasmembers. Mythesis is

thatthe"populationproblem,"ascon-

ventionallyconceived,isamemberof

thisclass.Howitisconventionallycon-

ceivedneedssomecomment. Itisfair

tosay thatmost people who'anguish

overthepopulationproblemaretrying

populationwithoutrelinquishinganyof

the privileges they now enjoy. They

thinkthatfarmingtheseasordevelop-

ingnewstrainsofwheatwillsolvethe

problem-technologically.Itrytoshow

43 KiB

Raw Blame History