Whatdoesthismean？Theproducersofcornwillhavetwosacksfortheirservices，whichtogetherwillbeworthwhatasinglesackwasworth，andtheproducersofclothwillhavetwopieces，whichtogetherwillbeworthwhatonewasworth。Intheexchangecalledproductionthesameserviceswillhaveobtained，eachintheirplace，adoublequantityofproduction，butthesetwodoublequantitiesmaybeobtainedonebytheotherasheretofore，andaseasilyso，thatwithoutlayingoutmoreinproductiveservices，anationinwhichthisproductivepowerbeginstounfolditself，willhavedoublethequantityofarticlestoconsume，eitherwheat，orcloth，oranythingelse，sincewehaveagreedtorepresentbywheatandclotheverythingthehumanspeciesmaywantforitssupport。Theproductionsinsuchanexchangeareopposedinvaluetoproductiveservices。Now，asineveryexchangeoneofthetwoarticlesisofgreatervalue，inproportiontothequantityitobtainsoftheother，itfollows，thatproductiveservicesarethemorevaluableinproportionasproductionsaremultiplied，andatlowerprice。（13）
Thisisthereasonwhythediminutioninthepriceofproductions，byaugmentingthevalueoftheproductivefundsofanation，andtherevenuesresultingtherefrom，increasesthenationalwealth。Thisdemonstration，whichisdetailedinthe3rdChapterofthe2d。BookofmyTreatiseonPoliticalEconomy（4thedition），hasIthinkrenderedsomeservicetothesciencebyexplainingthatwhichuptothatperiodhadbeenfeltbutnotexplained。Whichis，thatalthoughwealthisachangeablevalue，generalwealthhasaccruedbythelowpriceofcommoditiesandeverykindofproduction。（14）
Neverperhapshasanincreaseofdoubleintheproductivepoweroflabortakenplaceallatonce，andinallproductionsatthesametime，butitisindisputablethatithastakenplacegraduallyinmanyproductions，andinveryvariedproportions。Apurplecloakamongsttheancients，ofthesamequalityandsize，ofthesamesolidityandbeautyofcolor，costnodoubtdoublewhatitcostsnow。AndIhavenodoubtthatwheat，paidinlabor，isdiminishedonehalfatleastsincetheunknownepochaoftheinventionoftheplough。Alltheseproductionscostinglesslabor，havebeen，inconsequenceofcompetition，givenforwhattheycost，withoutanyonebeingaloserbyit，andalltheworldhasgainedinrevenue。
Butwemustreturntothefirstpartofyourobjection。Theproducersofwheatandtheproducersofclothwillthenproducemorewheatandcloththaneithertheoneortheothercanconsume。Ah!Sir，afterhavingprovedthatnotwithstandingareductionofmorethanhalfthevalueoftheproductionsthesamelaborcouldbuythewholeofthem，andtherebyprocuredoublethemeansofexistenceandenjoyment，shallIbereducedtothenecessityofprovingtothejustlycelebratedauthoroftheEssayonPopulationthateverythingthatcanbeproducedmayfindconsumers，andthatamongsttheenjoymentswhichthequantityofproductionsofwhichmankindcandispose，procure，thecomfortsofhomeandtheincreaseofchildrenarenottheleast？Afterhavingwrittenthreejustlyadmiredvolumestoprovethatthepopulationalwaysrisestothelevelofthemeansofexistence，canyouadmitthecaseofagreatincreaseofproductions，withastationarynumberofconsumers，andwantsreducedbyparsimony？
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