ought to produce an outcome similar to what would result if the transaction costs were eliminated. However, there is no cost-effective method of determining precisely what that outcome would be, by definition. So Coase argues that the courts should only intervene in cases that cause an unreasonable amount of nuisance after a wide analysis with regard to the total effect of such interventions. Additionally, Coase highlights reciprocity of harms present in externalities as a central question for distributing rights. Damage is shared between parties in a dispute, such that both parties consider the present costs in their optimization question. Coase uses the ruling of "Bryant v. Lefever" to explore the reciprocal nature of externality. Bryant v. Lefever concerns a conflict between neighbors, in which one neighbor constructed a wall such that the other neighbor’s chimney would smoke. Originally, the court determined the wall was the cause of the chimneys smoking and awarded the plaintiff financial compensation. However, in the Court of Appeals, this judgment was reversed. Coase argues that this judgment provides context for framing blame. According to Coase, “The smoke nuisance was caused both by the man who built the wall and by the man who lit the fires”. Under this framework, the wall-builder is not legally liable for the nuisance suffered by his neighbor alone. In this example, Coase seeks to illuminate the conditions for optimizing the allocation of rights, the case in which both parties consider harmful. Here, Coase is referencing Pareto efficiency allowed by the prevailing “pricing system”. Coase extends this framework throughout his development of a functional theorem concerning externalities. Coase argues that these rights are integrated into an actor's decision-making process through their unique cost function. These costs are not isolated in nature, according to Coase, who concluded “The cost of exercising a right (of using a factor of production) is always the loss which is suffered elsewhere” The ultimate thesis is that law and regulation are not as important or effective at helping people as lawyers and government planners believe. Coase and others like him wanted a change of approach, to put the burden of proof for positive effects on a government that was intervening in the market, by analysing the costs of the action. The argument forms the basis of the Coase Theorem as labeled by George Stigler. Theoretical challenges Guido Calabresi in his book The Costs of Accidents (1970) argues that