MalthusandtheImpossibilityofProgress?

Prof.JoshuaR.GoldsteinEconomicDemographyEcon/Demog c175Week2:LectureB

Spring2018

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Announcements

• StudyhallthisFridayat2232Piedmont(2-4)• Forlab,youwillneedtoabitofextrareadinginMalthus’s2nd editionaboutchecksinNorwayandSweden.(linkisinlab)

• Howmanyhave_not_successfullyaccessedourRstudio cloud?

• Howmanywenttosection?

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OurAgenda

• Dismalconclusions–Mortality?– Technology?– Fertility?

• Sauvy's "subsisistence"vs.Malthus'sequlibrium wage

• WasMalthusrightabouthisowntime?• HowdidMalthusgetthefuturewrong?

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Awarmup(review)Whatdowemeanbystable

equilibium?• StableEquilibrium• Ifwearemovedawayfrom

N*,wewillrevertback.• Exchangethebirthand

deathcurves(sobirthsgodownwithw,anddeathsgoup)

• Isw*stillanequilibrium?Isitstable?

w*

N*

b(w)

d(w)

w(N)

Wage(w)

Wage(w)

Crudebirthanddeathrates

Pop.Size(N)

>>><<<

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Theimpossibilityofprogress

• Somegoodthingscanbebad• Othergoodthingsmayprovideonlytemporaryrelief

• Istherenothinggood?Istherenohopeforthe“improvabilityofmankind”?

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Case1:Canagoodthingbebad?

• VaccinationagainstsmallpoxstartedinMalthus’stime(Jenner1796).Wouldthisimprove standardofliving,makelifelesshard?

• Let’smodelasaloweringofthemortalitycurve

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Loweringthedeathrate

• Whathappenstopopulationgrowthrate?

• Populationsize?• Equilibrium?

[let’scheckwiththeApp]

w*

N*

b(w)

d(w)

w(N)

Wage(w)

Wage(w)

Crudebirthanddeathrates

Pop.Size(N)

d’(w)

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MalthusiandarknessInsteadofrecommendingcleanlinesstothepoor,weshouldencouragecontraryhabits.Inourtownsweshouldmakethestreetsnarrower,crowdmorepeopleintothehouses,andcourtthereturnoftheplague.Inthecountry,weshouldbuildourvillagesnearstagnantpools,andparticularlyencouragesettlementsinallmarshyandunwholesomesituations

(Malthus,Essay,2nd edition,IV.V.1)

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Case2.“Technologycansaveus,right?"

• Newformsofenergy,bettercrops,improvingmethodsofeverything...

• Howdowegraphthis?• Doesitimprovethingsintheshortrun?

• Whatdoesanddoesnotchangeinthelong-run?(important)

• Dismal,right?9

w*

N*

b(w)

d(w)

w(N)

Wage(w)

Wage(w)

Crudebirthanddeathrates

Pop.

virtualiClicker

TechnologicalimprovementsraisethestandardoflivingonlytemporarilyinaMalthusianeconomy

A. True(becausepopulationgrowthwilleventuallyeatawayanygains)

B. False(becausewagesincrease,eveninthelongterm)

C. False(becauserepeatedtechnologicalimprovementscouldstopwagesfromfalling)

D. “C”soundslikeithasanelementoftruthbutI’mstickingwith“A”

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Case3:Less“Freelove”

• Socialcontrol(church,army,village)stoppedpeoplefrommarrying(e.g.,Norwayreading)

• Whatifsocietybecamemorefreeandmarriageeasier?

• MalthusarguesthatChinapoorerthanEuropebecausefewerlimitsonmarriage

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CompareBeijingtoAmsterdamorLondon

MalthusonChinaCulture,notbiology

...theextraordinaryencouragementsthathavebeengiventomarriage,whichhavecausedtheimmenseproduceofthecountrytobedividedintoverysmallshares,andhaveconsequentlyrenderedChinamorepopulous,inproportiontoitsmeansofsubsistence,thanperhapsanyothercountryintheworld.I.XII.14 ...themarriageunionassuchtakesplaceinChina,whereverthereistheleastprospectofsubsistenceforafuturefamily.Thisprospecthoweverisnotalwaysrealized,andthechildrenarethenabandonedbythewretchedauthorsoftheirbeing...Contemplatingthisextremeresourcebeforehand,lessfearisentertainedofenteringintothemarriedstate;....Marriagewiththepoorisbesidesameasureofprudence,becausethechildren,particularlythesons,areboundtomaintaintheirparents.

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poorandcrowded

nobarrierstomarriage

infanticide

son-preferenceandparentalobligations

Whyisthis"preventive"checksoappealingtoMalthus?

• Whathappenstostandardoflivingifwelowerbirthrate?

• Whathappenstodeathrate?

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w*

N*

b(w)

d(w)

w(N)

Wage(w)

Crudebirthanddeathrates

Pop.

WhydidMalthuslikethepreventivecheck?

• Raisingtheeconomicbartomarriagelowersfertilityatallwages

• Increasestheequilibriumwage• Lowersequilibriumdeathrates

Extraquestions?• Howdoesthisrelatetopoorlaws?• Whomightbeagainstthis?(Hint:thinkaboutSauvy's twooptima)

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virtualiclicker

Whichofthefollowingpoliciesmightarulerwantingtomaximizepowerfavor?

A.Liberalizingrestrictionstomarriage?B.Foodsubsidiestoreducethedeathrate?C.Scientificresearchtoincreaseproductivity?D.Higherwagesforworkers?

Note:cananswermorethan1

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Subsistencevs.MalthusianEquilibrium

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w*

N*

b(w)

d(w)

w(N)

Wage(w)

Crudebirthanddeathrates

Pop.

Oecon

output

Opow Omax

mp ap subsistencereq.

• "subsistence'abiologicalnotion• w*determinedbydemographicbehavior:

b(w)andd(w),independentofeconomyw(N)

• Whatisrelationshipbetweenw*&s?• WhatisrelationshipbetweenN*&various• optimaO?

subsistencereq.

EmpiricalExplorations(andintrotoourlab)

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Swedishseriesofbirthsanddeaths

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Ourscatterplot

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Lab

1. You’llexploretheseriesofbirthsanddeaths2. ReplicatetheplotIjustdid3. Seeifwecandetectbreakingdownofthe

Malthusiansystem

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WhatdidMalthusgetwrong?

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Wait,whosaysMalthuswaswrong?

• Maybeprogressisreallyimpossible.• Inthelong-run,itcouldstillbethatweareoverpopulated(aboveequilibrium)andcivilizationwillcrash.

• (WewillreturntothiswhenwereadLamandlookatresourceconstraints)

• Butfornow,let’sseehowMalthusgotthelast200yearswrong.

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Yourideas?

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Birthfunction?

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Deathfunction?

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Economy?(1)

• Maybeproductivityincreasesathigherpopulationdensities?

• Wecansketch• Accordingtothistheory(whichwewillexplorewhenwegettoBoserup),youneedacriticaldensitytotakeoff.

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Economy(2)

• Whathappensifweaddcapital?• Malthushas1fixed-resource(land),and1variable-resource(labor)

• Whatifwehave2variableresources(laborandcapital)?

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Nexttime

• Theneo-classicalgrowthmodel(Solow-Swann)

• We’llseeanewdynamicalsystem,with“birth”and“death”ofcapitalstock,andanewequilibrium

• We’llseewhatkindofprogressisthenpossible

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