TheProblemofSocialCostRonaldH.CoarseTheCore:ExternalityTraditionalViewsMarketfailureNon-marketpowerPlaceataxonthoseliableforthedamageViewsofCoaseParetoOptimalityTheReciprocalNatureoftheproblemModelwithouttransactioncostsAslongasthepropertyrighthasbeendelimitateddefinitely,itmakesnodifferenceofthedelimitationitself.Itwillleadtotheoutputvaluemaximization.ModelwithTransactionCostsTheinitialdelimitationoflegalrightsdoeshaveaneffectontheefficiencywithwhichtheeconomicsystemoperates.SubstituteEnterprise——thenatureofthefirmGovernment——directgovernmentalregulation1.Institutealegalsystemofrightswhichcanbemodifiedbytransactionsonthemarket.2.Statewhatpeoplemustormustnotdo.3.DonothingabouttheproblematallCriticismDamagedonetosurroundingwoodsbysparksfromrailwayengines.Whetherit’sdesirableornotdependsontheparticularcircumstances.ChangethemethodsThechoicebetweendifferentsocialarrangementsforthesolutionofeconomicproblemsshouldbecarriedoutinbroaderterms.Factorsofproductionshouldbethoughtofasrights,thenthecostofexercisingarightisthelosswhichissufferedelsewhereinconsequenceoftheexerciseofthatright.