Inourformerassumption，accordingtowhich6workinghoursaredailynecessaryinordertoreproducethelabour—poweritselfortoreplacethevalueofthecapitaladvancedinitspurchase，avariablecapitalof1，500s。，thatemploys500labourersatarateofsurplusvalueof100%witha12hours’
　　workingday，producesdailyasurplusvalueof1，500s。orof6x500workinghours。
　　Acapitalof300s。thatemploys100labourersadaywitharateofsurplusvalueof200%orwithaworkingdayof18hours，producesonlyamassofsurplusvalueof600s。or12x100workinghours;anditstotalvalue—product，theequivalentofthevariablecapitaladvancedplusthesurplus—value，can，dayin，dayout，neverreachthesumof1，200s。or24x100workinghours。Theabsolutelimitoftheaverageworkingday？thisbeingbynaturealwayslessthan24hours？setsanabsolutelimittothecompensationofareductionofvariablecapitalbyahigherrateofsurplusvalue，orofthedecreaseofthenumberoflabourersexploitedbyahigherdegreeofexploitationoflabour—power。Thispalpablelawisofimportancefortheclearingupofmanyphenomena，arisingfromatendency（tobeworkedoutlateron）ofcapitaltoreduceasmuchaspossiblethenumberoflabourersemployedbyit，oritsvariableconstituenttransformedintolabour—power，incontradictiontoitsothertendencytoproducethegreatestpossiblemassofsurplusvalue。
　　Ontheotherhand，ifthemassoflabour—poweremployed，ortheamountofvariablecapital，increases，butnotinproportiontothefallintherateofsurplusvalue，themassofthesurplusvalueproduced，falls。
　　Athirdlawresultsfromthedetermination，ofthemassofthesurplus—valueproduced，bythetwofactors:rateofsurplusvalueandamountofvariablecapitaladvanced。Therateofsurplusvalue，orthedegreeofexploitationoflabour—power，andthevalueoflabour—power，ortheamountofnecessaryworkingtimebeinggiven，itisselfevidentthatthegreaterthevariablecapital，thegreaterwouldbethemassofthevalueproducedandofthesurplusvalue。Ifthelimitoftheworking—dayisgiven，andalsothelimitofitsnecessaryconstituent，themassofvalueandsurplusvaluethatanindividualcapitalistproduces，isclearlyexclusivelydependentonthemassoflabourthathesetsinmotion。Butthis，undertheconditionssupposedabove，dependsonthemassoflabour—power，orthenumberoflabourerswhomheexploits，andthisnumberinitsturnisdeterminedbytheamountofthevariablecapitaladvanced。Withagivenrateofsurplusvalue，andagivenvalueoflabour—power，therefore，themassesofsurplusvalueproducedvarydirectlyastheamountsofthevariablecapitalsadvanced。Nowweknowthatthecapitalistdivideshiscapitalintotwoparts。Oneparthelaysoutinmeansofproduction。Thisistheconstantpartofhiscapital。Theotherparthelaysoutinlivinglabour—power。
　　Thispartformshisvariablecapital。Onthebasisofthesamemodeofsocialproduction，thedivisionofcapitalintoconstantandvariablediffersindifferentbranchesofproduction，andwithinthesamebranchofproduction，too，thisrelationchangeswithchangesinthetechnicalconditionsandinthesocialcombinationsoftheprocessesofproduction。Butinwhateverproportionagivencapitalbreaksupintoaconstantandavariablepart，whetherthelatteristotheformeras1:2or1:10or1:x，thelawjustlaiddownisnotaffectedbythis。For，accordingtoourpreviousanalysis，thevalueoftheconstantcapitalreappearsinthevalueoftheproduct，butdoesnotenterintothenewlyproducedvalue，thenewlycreatedvalueproduct。
　　Toemploy1，000spinners，morerawmaterial，spindles，&c。，are，ofcourse，required，thantoemploy100。Thevalueoftheseadditionalmeansofproductionhowevermayrise，fall，remainunaltered，belargeorsmall;
　　ithasnoinfluenceontheprocessofcreationofsurplusvaluebymeansofthelabour—powersthatputtheminmotion。Thelawdemonstratedabovenow，therefore，takesthisform:themassesofvalueandofsurplusvalueproducedbydifferentcapitals？thevalueoflabour—powerbeinggivenanditsdegreeofexploitationbeingequal？varydirectlyastheamountsofthevariableconstituentsofthesecapitals，i。e。，astheirconstituentstransformedintolivinglabour—power。
　　Thislawclearlycontradictsallexperiencebasedonappearance。
　　Everyoneknowsthatacottonspinner，who，reckoningthepercentageonthewholeofhisappliedcapital，employsmuchconstantandlittlevariablecapital，doesnot，onaccountofthis，pocketlessprofitorsurplusvaluethanabaker，whorelativelysetsinmotionmuchvariableandlittleconstantcapital。Forthesolutionofthisapparentcontradiction，manyintermediatetermsareasyetwanted，asfromthestandpointofelementaryalgebramanyintermediatetermsarewantedtounderstandthat0/0mayrepresentanactualmagnitude。Classicaleconomy，althoughnotformulatingthelaw，holdsinstinctivelytoit，becauseitisanecessaryconsequenceofthegenerallawofvalue。
　　Ittriestorescuethelawfromcollisionwithcontradictoryphenomenabyaviolentabstraction。Itwillbeseenlater[2]howtheschoolofRicardohascometogriefoverthisstumblingblock。Vulgareconomywhich，indeed，"hasreallylearntnothing，"hereaseverywherestickstoappearancesinoppositiontothelawwhichregulatesandexplainsthem。InoppositiontoSpinoza，itbelievesthat"ignoranceisasufficientreason。"
　　Thelabourwhichissetinmotionbythetotalcapitalofasociety，dayin，dayout，mayberegardedasasinglecollectiveworkingday。If，e。g。，thenumberoflabourersisamillion，andtheaverageworking—dayofalaboureris10hours，thesocialworkingdayconsistsoftenmillionhours。Withagivenlengthofthisworkingday，whetheritslimitsarefixedphysicallyorsocially，themassofsurplusvaluecanonlybeincreasedbyincreasingthenumberoflabourers，i。e。，ofthelabouringpopulation。
　　Thegrowthofpopulationhereformsthemathematicallimittotheproductionofsurplusvaluebythetotalsocialcapital。Onthecontrary，withagivenamountofpopulation，thislimitisformedbythepossiblelengtheningoftheworkingday。[3]Itwill，however，beseeninthefollowingchapterthatthislawonlyholdsfortheformofsurplusvaluedealtwithuptothepresent。
　　Fromthetreatmentoftheproductionofsurplusvalue，sofar，itfollowsthatnoteverysumofmoney，orofvalue，isatpleasuretransformableintocapital。Toeffectthistransformation，infact，acertainminimumofmoneyorofexchangevaluemustbepresupposedinthehandsoftheindividualpossessorofmoneyorcommodities。Theminimumofvariablecapitalisthecostpriceofasinglelabour—power，employedthewholeyearthrough，dayin，dayout，fortheproductionofsurplusvalue。Ifthislabourerwereinpossessionofhisownmeansofproduction，andweresatisfiedtoliveasalabourer，heneednotworkbeyondthetimenecessaryforthereproductionofhismeansofsubsistence，say8hoursaday。Hewould，besides，onlyrequirethemeansofproductionsufficientfor8workinghours。Thecapitalist，ontheotherhand，whomakeshimdo，besidesthese8hours，say4hours’
　　surplus—labour，requiresanadditionalsumofmoneyforfurnishingtheadditionalmeansofproduction。Onoursupposition，however，hewouldhavetoemploytwolabourersinordertolive，onthesurplusvalueappropriateddaily，aswellas，andnobetterthanalabourer，i。e。，tobeabletosatisfyhisnecessarywants。Inthiscasethemeremaintenanceoflifewouldbetheendofhisproduction，nottheincreaseofwealth;butthislatterisimpliedincapitalistproduction。Thathemayliveonlytwiceaswellasanordinarylabourer，andbesidesturnhalfofthesurplusvalueproducedintocapital，hewouldhavetoraise，withthenumberoflabourers，theminimumofthecapitaladvanced8times。
　　Ofcoursehecan，likehislabourer，taketoworkhimself，participatedirectlyintheprocessofproduction，butheisthenonlyahybridbetweencapitalistandlabourer，a"smallmaster。"Acertainstageofcapitalistproductionnecessitatesthatthecapitalistbeabletodevotethewholeofthetimeduringwhichhefunctionsasacapitalist，i。e。，aspersonifiedcapital，totheappropriationandthereforecontrolofthelabourofothers，andtothesellingoftheproductsofthislabour。[4]Theguildsofthemiddleagesthereforetriedtopreventbyforcethetransformationofthemasterofatradeintoacapitalist，bylimitingthenumberoflabourersthatcouldbeemployedbyonemasterwithinaverysmallmaximum。Thepossessorofmoneyorcommoditiesactuallyturnsintoacapitalistinsuchcasesonlywheretheminimumsumadvancedforproductiongreatlyexceedsthemaximumofthemiddleages。Here，asinnaturalscience，isshownthecorrectnessofthelawdiscoveredbyHegel（inhis"Logic"），thatmerelyquantitativedifferencesbeyondacertainpointpassintoqualitativechanges。[5]
　　Theminimumofthesumofvaluethattheindividualpossessorofmoneyorcommoditiesmustcommand，inordertometamorphosehimselfintoacapitalist，changeswiththedifferentstagesofdevelopmentofcapitalistproduction，andisatgivenstagesdifferentindifferentspheresofproduction，accordingtotheirspecialandtechnicalconditions。
　　Certainspheresofproductiondemand，evenattheveryoutsetofcapitalistproduction，aminimumofcapitalthatisnotasyetfoundinthehandsofsingleindividuals。Thisgivesrisepartlytostatesubsidiestoprivatepersons，asinFranceinthetimeofClobber，andasinmanyGermanstatesuptoourownepoch，partlytotheformationofsocietieswithlegalmonopolyfortheexploitationofcertainbranchesofindustryandcommerce，theforerunnersofourmodernjointstockcompanies。[6]
　　Withintheprocessofproduction，aswehaveseen，capitalacquiredthecommandoverlabour，i。e。，overfunctioninglabour—powerorthelabourerhimself。Personifiedcapital，thecapitalisttakescarethatthelabourerdoeshisworkregularlyandwiththeproperdegreeofintensity。
　　Capitalfurtherdevelopedintoacoerciverelation，whichcompelstheworkingclasstodomoreworkthanthenarrowroundofitsownlifewantsprescribes。Asaproduceroftheactivityofothers，asapumper—outofsurpluslabourandexploiteroflabour—power，itsurpassesinenergy，disregardofbounds，recklessnessandefficiency，allearliersystemsofproductionbasedondirectlycompulsorylabour。
　　Atfirst，capitalsubordinateslabouronthebasisofthetechnicalconditionsinwhichithistoricallyfindsit。Itdoesnot，therefore，changeimmediatelythemodeofproduction。Theproductionofsurplusvalue？intheformhithertoconsideredbyus？bymeansofsimpleextensionoftheworkingday，proved，therefore，tobeindependentofanychangeinthemodeofproductionitself。Itwasnotlessactiveintheoldfashionedbakeriesthaninthemoderncottonfactories。
　　Ifweconsidertheprocessofproductionfromthepointofviewofthesimplelabourprocess，thelabourerstandsinrelationtothemeansofproduction，notintheirqualityascapital，butasthemeremeansandmaterialofhisownintelligentproductiveactivity。Intanning，e。g。，hedealswiththeskinsashissimpleobjectoflabour。Itisnotthecapitalistwhoseskinhetans。Butitisdifferentassoonaswedealwiththeprocessofproductionfromthepointofviewoftheprocessofcreationofsurplusvalue。
　　Themeansofproductionareatoncechangedintomeansfortheabsorptionofthelabourofothers。Itisnownolongerthelabourerthatemploysthemeansofproduction，butthemeansofproductionthatemploythelabourer。Insteadofbeingconsumedbyhimasmaterialelementsofhisproductiveactivity，theyconsumehimasthefermentnecessarytotheirownlifeprocess，andthelifeprocessofcapitalconsistsonlyinitsmovementasvalueconstantlyexpanding，constantlymultiplyingitself。
　　Furnacesandworkshopsthatstandidlebynight，andabsorbnolivinglabour，are"amereloss"tothecapitalist。Hence，furnacesandworkshopsconstitutelawfulclaimsuponthenightlabourofthework—people。
　　Thesimpletransformationofmoneyintothematerialfactorsoftheprocessofproduction，intomeansofproduction，transformsthelatterintoatitleandarighttothelabourandsurpluslabourofothers。Anexamplewillshow，inconclusion，howthissophistication，peculiartoandcharacteristicofcapitalistproduction，thiscompleteinversionoftherelationbetweendeadandlivinglabour，betweenvalueandtheforcethatcreatesvalue，mirrorsitselfintheconsciousnessofcapitalists。
　　DuringtherevoltoftheEnglishfactorylordsbetween1848and1850，"theheadofoneoftheoldestandmostrespectablehousesintheWestofScotland，Messrs。CarlileSons&Co。，ofthelinenandcottonthreadfactoryatPaisley，acompanywhichhasnowexistedforaboutacentury，whichwasinoperationin1752，andfourgenerationsofthesamefamilyhaveconductedit"……this"veryintelligentgentleman"thenwrotealetter[7]intheGlasgowDailyMailofApril25th，1849，withthetitle，"Therelaysystem，"inwhichamongotherthingsthefollowinggrotesquelynaïvepassageoccurs:"Letusnow……seewhatevilswillattendthelimitingto10hourstheworkingofthefactory……Theyamounttothemostseriousdamagetothemillowner’sprospectsandproperty。Ifhe（i。e。，his"hands"）
　　worked12hoursbefore，andislimitedto10，thenevery12machinesorspindlesinhisestablishmentshrinkto10，andshouldtheworksbedisposedof，theywillbevaluedonlyas10，sothatasixthpartwouldthusbedeductedfromthevalueofeveryfactoryinthecountry。"[8]
　　TothisWestofScotlandbourgeoisbrain，inheritingtheaccumulatedcapitalisticqualitiesof"fourgenerations。"thevalueofthemeansofproduction，spindles，&c。，issoinseparablymixedupwiththeirproperty，ascapital，toexpandtheirownvalue，andtoswallowupdailyadefinitequantityoftheunpaidlabourofothers，thattheheadofthefirmofCarlile&Co。actuallyimaginesthatifhesellshisfactory，notonlywillthevalueofthespindlesbepaidtohim，but，inaddition，theirpowerofannexingsurplusvalue，notonlythelabourwhichisembodiedinthem，andisnecessarytotheproductionofspindlesofthiskind，butalsothesurpluslabourwhichtheyhelptopumpoutdailyfromthebraveScotsofPaisley，andforthatveryreasonhethinksthatwiththeshorteningoftheworkingdayby2hours，thesellingpriceof12spinningmachinesdwindlestothatof10！
　　Footnotes[1]Thiselementarylawappearstobeunknowntothevulgareconomists，who，upside—downArchimedes，inthedeterminationofthemarket—priceoflabourbysupplyanddemand，imaginetheyhavefoundthefulcrumbymeansofwhich，nottomovetheworld，buttostopitsmotion。
　　[2]FurtherparticularswillbegiveninBookIV。
　　[3]"TheLabour，thatistheeconomictime，ofsociety，isagivenportion，saytenhoursadayofamillionofpeople，ortenmillionhours……Capitalhasitsboundaryofincrease。Thisboundarymay，atanygivenperiod，beattainedintheactualextentofeconomictimeemployed。"（"AnEssayonthePoliticalEconomyofNations。"London，1821，pp。47，49。）
　　[4]"Thefarmercannotrelyonhisownlabour，andifhedoes，Iwillmaintainthatheisaloserbyit。Hisemploymentshouldbeageneralattentiontothewhole:histhreshermustbewatched，orhewillsoonlosehiswagesincornnotthreshedout，hismowersreapers，&c。，mustbelookedafter;
　　hemustconstantlygoroundhisfences;hemustseethereisnoneglect;
　　whichwouldbethecaseifhewasconfinedtoanyonespot。"（’`AnInquiryintotheConnexionbetweenthePresentPriceofProvisionsandtheSizeofFarms，&c。ByaFarmer。"London，1773，p。12。）Thisbookisveryinteresting。Initthegenesisofthe"capitalistfarmer"or"merchantfarmer，"asheisexplicitlycalled，maybestudied，andhisselfglorificationattheexpenseofthesmallfarmerwhohasonlytodowithbaresubsistence，benoted。"Theclassofcapitalistsarefromthefirstpartially，andtheybecomeultimatelycompletely，dischargedfromthenecessityofthemanuallabour。"（"TextbookofLecturesonthePoliticalEconomyofNations。BytheRev。RichardJones。"Hertford1852。LectureIII。，p。39。）
　　[5]ThemoleculartheoryofmodernchemistryfirstscientificallyworkedoutbyLaurentandGerhardtrestsonnootherlaw。（Additionto3rdEdition。）
　　Fortheexplanationofthisstatement，whichisnotverycleartononchemists，weremarkthattheauthorspeakshereofthehomologousseriesofcarboncompounds，firstsonamedbyC。Gerhardtin1843，eachseriesofwhichhasitsowngeneralalgebraicformula。Thustheseriesofparaffins:CnH2n2，thatofthenormalalcohols:CnH2n2O;ofthenormalfattyacids:CnH2nO2
　　andmanyothers。Intheaboveexamples，bythesimplyquantitativeadditionofCH2tothemolecularformula，aqualitativelydifferentbodyiseachtimeformed。Ontheshare（overestimatedbyMarx）ofLaurentandGerhardtinthedeterminationofthisimportantfactseeKopp，"EntwicklungderChemie。"Munchen，1873，pp。709，716，andSchorkmmer，’TheRiseandDevelopmentofOrganicChemistry。"London，1879，p。54。？F。E。
　　[6]MartinLuthercallsthesekindsofinstitutions:"TheCompanyMonopolia。"
　　[7]ReportsofInsp。ofFact。，April30th，1849，p。59。
　　[8]l。c。，p。60。FactoryInspectorStuart，himselfaScotchman，andincontrasttotheEnglishFactoryInspectors，quitetakencaptivebythecapitalisticmethodofthinking，remarksexpresslyonthisletterwhichheincorporatesinhisreportthatitis"themostusefulofthecommunicationswhichanyofthefactoryownersworkingwithrelayshavegiventothoseengagedinthesametrade，andwhichisthemostcalculatedtoremovetheprejudicesofsuchofthemashavescruplesrespectinganychangeofthearrangementofthehoursofwork。"
　　ChapterTwelveKarlMarxCapitalVolumeOnePartIV:
　　ProductionofRelativeSurplusValueCHAPTERTWELVE:
　　THECONCEPTOFRELATIVESURPLUS—VALUE
　　Thatportionoftheworking—daywhichmerelyproducesanequivalentforthevaluepaidbythecapitalistforhislabour—power，has，uptothispoint，beentreatedbyusasaconstantmagnitude，andsuchinfactitis，undergivenconditionsofproductionandatagivenstageintheeconomicdevelopmentofsociety。Beyondthis，hisnecessarylabour—time，thelabourer，wesaw，couldcontinuetoworkfor2，3，4，6，&c。，hours。Therateofsurplus—valueandthelengthoftheworking—daydependedonthemagnitudeofthisprolongation。Thoughthenecessarylabour—timewasconstant，wesaw，ontheotherhand，thatthetotalworking—daywasvariable。Nowsupposewehaveaworking—daywhoselength，andwhoseapportionmentbetweennecessarylabourandsurplus—labour，aregiven。Letthewholelineac，abcrepresent，forexample，aworking—dayof12hours;theportionofab10hoursofnecessarylabour，andtheportionbc2hoursofsurplus—labour。Hownowcantheproductionofsurplus—valuebeincreased，i。e。，howcanthesurplus—labourbeprolonged，without，orindependentlyof，anyprolongationofac？
　　Althoughthelengthofacisgiven，bcappearstobecapableofprolongation，ifnotbyextensionbeyonditsendc，whichisalsotheendoftheworking—dayac，yet，atallevents，bypushingbackitsstarting—pointbinthedirectionofa。Assumethatb’binthelineab’bcisequaltohalfofbcortoonehour’slabour—time。Ifnow，inac，theworking—dayof12hours，wemovethepointbtob’，bcbecomesb’c;thesurplus—labourincreasesbyonehalf，from2hoursto3hours，althoughtheworking—dayremainsasbeforeat12hours。Thisextensionofthesurpluslabour—timefrombctob’c，from2hoursto3hours，is，however，evidentlyimpossible，withoutasimultaneouscontractionofthenecessarylabour—timefromabintoab’，from10hoursto9hours。Theprolongationofthesurplus—labourwouldcorrespondtoashorteningofthenecessarylabour;oraportionofthelabour—timepreviouslyconsumed，inreality，forthelabourer’sownbenefit，wouldbeconvertedintolabour—timeforthebenefitofthecapitalist。Therewouldbeanalteration，notinthelengthoftheworking—day，butinitsdivisionintonecessarylabour—timeandsurpluslabour—time。
　　Ontheotherhand，itisevidentthatthedurationofthesurplus—labourisgiven，whenthelengthoftheworking—day，andthevalueoflabour—power，aregiven。Thevalueoflabour—power，i。e。，thelabour—timerequisitetoproducelabour—power，determinesthelabour—timenecessaryforthereproductionofthatvalue。Ifoneworking—hourbeembodiedinsixpence，andthevalueofaday’slabour—powerbefiveshillings，thelabourermustwork10hoursaday，inordertoreplacethevaluepaidbycapitalforhislabour—power，ortoproduceanequivalentforthevalueofhisdailynecessarymeansofsubsistence。Giventhevalueofthesemeansofsubsistence，thevalueofhislabour—powerisgiven;[1]andgiventhevalueofhislabour—power，thedurationofhisnecessarylabour—timeisgiven。Thedurationofthesurplus—labour，however，isarrivedat，bysubtractingthenecessarylabour—timefromthetotalworking—day。
　　Tenhourssubtractedfromtwelve，leavetwo，anditisnoteasytosee，how，underthegivenconditions，thesurplus—labourcanpossiblybeprolongedbeyondtwohours。Nodoubt，thecapitalistcan，insteadoffiveshillings，paythelabourerfourshillingsandsixpenceorevenless。Forthereproductionofthisvalueoffourshillingsandsixpence，ninehours’labour—timewouldsuffice;andconsequentlythreehoursofsurplus—labour，insteadoftwo，wouldaccruetothecapitalist，andthesurplus—valuewouldrisefromoneshillingtoeighteen—pence。Thisresult，however，wouldbeobtainedonlybyloweringthewagesofthelabourerbelowthevalueofhislabour—power。
　　Withthefourshillingsandsixpencewhichheproducesinninehours，hecommandsone—tenthlessofthenecessariesoflifethanbefore，andconsequentlytheproperreproductionofhislabour—poweriscrippled。Thesurplus—labourwouldinthiscasebeprolongedonlybyanoversteppingofitsnormallimits;itsdomainwouldbeextendedonlybyausurpationofpartofthedomainofnecessarylabour—time。Despitetheimportantpartwhichthismethodplaysinactualpractice，weareexcludedfromconsideringitinthisplace，byourassumption，thatallcommodities，includinglabour—power，areboughtandsoldattheirfullvalue。Grantedthis，itfollowsthatthelabour—timenecessaryfortheproductionoflabour—power，orforthereproductionofitsvalue，cannotbelessenedbyafallinthelabourer’swagesbelowthevalueofhislabour—power，butonlybyafallinthisvalueitself。Giventhelengthoftheworking—day，theprolongationofthesurplus—labourmustofnecessityoriginateinthecurtailmentofthenecessarylabour—time;
　　thelattercannotarisefromtheformer。Intheexamplewehavetaken，itisnecessarythatthevalueoflabour—powershouldactuallyfallbyone—tenth，inorderthatthenecessarylabour—timemaybediminishedbyone—tenth，i。e。，fromtenhourstonine，andinorderthatthesurpluslabourmayconsequentlybeprolongedfromtwohourstothree。
　　Suchafallinthevalueoflabour—powerimplies，however，thatthesamenecessariesoflifewhichwereformerlyproducedintenhours，cannowbeproducedinninehours。Butthisisimpossiblewithoutanincreaseintheproductivenessoflabour。Forexample，supposeashoe—maker，withgiventools，makesinoneworking—dayoftwelvehours，onepairofboots。
　　Ifhemustmaketwopairsinthesametime，theproductivenessofhislabourmustbedoubled;andthiscannotbedone，exceptbyanalterationinhistoolsorinhismodeofworking，orinboth。Hence，theconditionsofproduction，i。e。，hismodeofproduction，andthelabour—processitself，mustberevolutionised。
　　Byincreaseintheproductivenessoflabour，wemean，generally，analterationinthelabour—process，ofsuchakindastoshortenthelabour—timesociallynecessaryfortheproductionofacommodity，andtoendowagivenquantityoflabourwiththepowerofproducingagreaterquantityofuse—value。[2]Hithertointreatingofsurplus—value，arisingfromasimpleprolongationoftheworking—day，wehaveassumedthemodeofproductiontobegivenandinvariable。Butwhensurplus—valuehastobeproducedbytheconversionofnecessarylabourintosurplus—labour，itbynomeanssufficesforcapitaltotakeoverthelabour—processintheformunderwhichithasbeenhistoricallyhandeddown，andthensimplytoprolongthedurationofthatprocess。Thetechnicalandsocialconditionsoftheprocess，andconsequentlytheverymodeofproductionmustberevolutionised，beforetheproductivenessoflabourcanbeincreased。Bythatmeansalonecanthevalueoflabour—powerbemadetosink，andtheportionoftheworking—daynecessaryforthereproductionofthatvalue，beshortened。
　　Thesurplus—valueproducedbyprolongationoftheworking—day，Icallabsolutesurplus—value。Ontheotherhand，thesurplus—valuearisingfromthecurtailmentofthenecessarylabour—time，andfromthecorrespondingalterationintherespectivelengthsofthetwocomponentsoftheworking—day，Icallrelativesurplus—value。
　　Inordertoeffectafallinthevalueoflabour—power，theincreaseintheproductivenessoflabourmustseizeuponthosebranchesofindustrywhoseproductsdeterminethevalueoflabour—power，andconsequentlyeitherbelongtotheclassofcustomarymeansofsubsistence，orarecapableofsupplyingtheplaceofthosemeans。Butthevalueofacommodityisdetermined，notonlybythequantityoflabourwhichthelabourerdirectlybestowsuponthatcommodity，butalsobythelabourcontainedinthemeansofproduction。
　　Forinstance，thevalueofapairofbootsdependsnotonlyonthecobbler’slabour，butalsoonthevalueoftheleather，wax，thread，&c。Hence，afallinthevalueoflabour—powerisalsobroughtaboutbyanincreaseintheproductivenessoflabour，andbyacorrespondingcheapeningofcommoditiesinthoseindustrieswhichsupplytheinstrumentsoflabourandtherawmaterial，thatformthematerialelementsoftheconstantcapitalrequiredforproducingthenecessariesoflife。Butanincreaseintheproductivenessoflabourinthosebranchesofindustrywhichsupplyneitherthenecessariesoflife，northemeansofproductionforsuchnecessaries，leavesthevalueoflabour—powerundisturbed。
　　Thecheapenedcommodity，ofcourse，causesonlyaprotantofallinthevalueoflabour—power，afallproportionaltotheextentofthatcommodity’semploymentinthereproductionoflabour—power。Shirts，forinstance，areanecessarymeansofsubsistence，butareonlyoneoutofmany。Thetotalityofthenecessariesoflifeconsists，however，ofvariouscommodities，eachtheproductofadistinctindustry;andthevalueofeachofthosecommoditiesentersasacomponentpartintothevalueoflabour—power。Thislattervaluedecreaseswiththedecreaseofthelabour—timenecessaryforitsreproduction;thetotaldecreasebeingthesumofallthedifferentcurtailmentsoflabour—timeeffectedinthosevariousanddistinctindustries。Thisgeneralresultistreated，here，asifitweretheimmediateresultdirectlyaimedatineachindividualcase。Wheneveranindividualcapitalistcheapensshirts，forinstance，byincreasingtheproductivenessoflabourhebynomeansnecessarilyaimsatreducingthevalueoflabour—powerandshortening，protantothenecessarylabour—time。
　　Butitisonlyinsofarasheultimatelycontributestothisresult，thatheassistsinraisingthegeneralrateofsurplus—value。[3]Thegeneralandnecessarytendenciesofcapitalmustbedistinguishedfromtheirformsofmanifestation。
　　Itisnotourintentiontoconsider，here，thewayinwhichthelaws，immanentincapitalistproduction，manifestthemselvesinthemovementsofindividualmassesofcapital，wheretheyassertthemselvesascoercivelawsofcompetition，andarebroughthometothemindandconsciousnessoftheindividualcapitalistasthedirectingmotivesofhisoperations。
　　Butthismuchisclear;ascientificanalysisofcompetitionisnotpossible，beforewehaveaconceptionoftheinnernatureofcapital，justastheapparentmotionsoftheheavenlybodiesarenotintelligibletoanybuthim，whoisacquaintedwiththeirrealmotions，motionswhicharenotdirectlyperceptiblebythesenses。Nevertheless，forthebettercomprehensionoftheproductionofrelativesurplus—value，wemayaddthefollowingremarks，inwhichweassumenothingmorethantheresultswehavealreadyobtained。
　　Ifonehour’slabourisembodiedinsixpence，avalueofsixshillingswillbeproducedinaworking—dayof12hours。Suppose，thatwiththeprevailingproductivenessoflabour，12articlesareproducedinthese12hours。Letthevalueofthemeansofproductionusedupineacharticlebesixpence。
　　Underthesecircumstances，eacharticlecostsoneshilling:sixpenceforthevalueofthemeansofproduction，andsixpenceforthevaluenewlyaddedinworkingwiththosemeans。Nowletsomeonecapitalistcontrivetodoubletheproductivenessoflabour，andtoproduceintheworking—dayof12hours，24insteadof12sucharticles。Thevalueofthemeansofproductionremainingthesame，thevalueofeacharticlewillfalltoninepence，madeupofsixpenceforthevalueofthemeansofproductionandthreepenceforthevaluenewlyaddedbythelabour。Despitethedoubledproductivenessoflabour，theday’slabourcreates，asbefore，anewvalueofsixshillingsandnomore，which，however，isnowspreadovertwiceasmanyarticles。
　　Ofthisvalueeacharticlenowhasembodiedinit1/24th，insteadof1/12th，threepenceinsteadofsixpence;or，whatamountstothesamething，onlyhalfanhour’sinsteadofawholehour’slabour—time，isnowaddedtothemeansofproductionwhiletheyarebeingtransformedintoeacharticle。
　　Theindividualvalueofthesearticlesisnowbelowtheirsocialvalue;inotherwords，theyhavecostlesslabour—timethanthegreatbulkofthesamearticleproducedundertheaveragesocialconditions。Eacharticlecosts，onanaverage，oneshilling，andrepresents2hoursofsociallabour;
　　butunderthealteredmodeofproductionitcostsonlyninepence，orcontainsonly1½hours’labour。Therealvalueofacommodityis，however，notitsindividualvalue，butitssocialvalue;thatistosay，therealvalueisnotmeasuredbythelabour—timethatthearticleineachindividualcasecoststheproducer，butbythelabour—timesociallyrequiredforitsproduction。Iftherefore，thecapitalistwhoappliesthenewmethod，sellshiscommodityatitssocialvalueofoneshilling，hesellsitforthreepenceaboveitsindividualvalue，andthusrealisesanextrasurplus—valueofthreepence。Ontheotherhand，theworking—dayof12hoursis，asregardshim，nowrepresentedby24articlesinsteadof12。Hence，inordertogetridoftheproductofoneworking—day，thedemandmustbedoublewhatitwas，i。e。，themarketmustbecometwiceasextensive。Otherthingsbeingequal，hiscommoditiescancommandamoreextendedmarketonlybyadiminutionoftheirprices。Hewillthereforesellthemabovetheirindividualbutundertheirsocialvalue，sayattenpenceeach。Bythismeanshestillsqueezesanextrasurplus—valueofonepennyoutofeach。Thisaugmentationofsurplus—valueispocketedbyhim，whetherhiscommoditiesbelongornottotheclassofnecessarymeansofsubsistencethatparticipateindeterminingthegeneralvalueoflabour—power。Hence，independentlyofthislattercircumstance，thereisamotiveforeachindividualcapitalisttocheapenhiscommodities，byincreasingtheproductivenessoflabour。
　　Nevertheless，eveninthiscase，theincreasedproductionofsurplus—valuearisesfromthecurtailmentofthenecessarylabour—time，andfromthecorrespondingprolongationofthesurplus—labour。[4]Letthenecessarylabour—timeamountto10hours，thevalueofaday’slabour—powertofiveshillings，thesurpluslabour—timeto2hours，andthedailysurplus—valuetooneshilling。Butthecapitalistnowproduces24articles，whichhesellsattenpencea—piece，makingtwentyshillingsinall。Sincethevalueofthemeansofproductionistwelveshillings，142/5ofthesearticlesmerelyreplacetheconstantcapitaladvanced。