CHAPTERII
THECIRCUITOFPRODUCTIVECAPITALThecircuitofproductivecapitalhasthegeneralformulaP……C’——M’——C……P。Itsignifiestheperiodicalrenewalofthefunctioningofproductivecapital，henceitsreproduction，oritsprocessofproductionasaprocessofreproductionaimingattheself-expansionofvalue；notonlyproductionbutaperiodicalreproductionofsurplus-value；thefunctionofindustrialcapitalinitsproductiveform，andthisfunctionperformednotoncebutperiodicallyrepeated，sothattherenewalisdeterminedbythestarting-point。
AportionofC’mayincertaincases，invariousbranchesofindustrialcapitalre-enterdirectlyasmeansofproductionintothesamelabour-processoutofwhichitcameintheshapeofacommodity。Thismerelysavesthetransformationofthevalueofthisportionintorealmoneyortoken-moneyorelsethecommodityfindsanindependentexpressiononlyasmoneyofaccount。Thispartofvaluedoesnotenterintothecirculation。Thusvaluesenterintotheprocessofproductionwhichdonotenterintotheprocessofcirculation。ThesameistrueofthatpartofC’whichisconsumedbythecapitalistinkindaspartofthesurplus-product。Butthisisinsignificantforcapitalistproduction。Itdeservesconsideration，ifatall，onlyinagriculture。
Twothingsareatoncestrikinglyapparentinthisform。
Foronething，whileinthefirstform，M……M’，theprocessofproduction，thefunctionofP，interruptsthecirculationofmoney-capitalandactsonlyasamediatorbetweenitstwophasesM——CandC’——M’，heretheentirecirculationprocessofindustrialcapital，itsentiremovementwithinthephaseofcirculation，constitutesonlyaninterruptionandconsequentlyonlytheconnectinglinkbetweentheproductivecapital，whichasthefirstextremeopensthecircuit，andthatwhichclosesitastheotherextremeinthesameform，henceintheforminwhichitstartsagain。Circulationproperappearsbutasaninstrumentpromotingtheperiodicallyrenewedreproduction，renderedcontinuousbytherenewal。