Coase Theorem

Questions

What is Coase Theorem?

The Coase Theorem, from economist Ronald Coase, says that if two parties can negotiate cheaply, they will reach the most efficient outcome to a shared harm, regardless of who has the legal right. The law decides who pays whom, not what finally happens.

How do you use Coase Theorem?

Use it in everyday conflicts: before arguing over who's right, ask what trade would leave both sides better off. But remember it breaks down when bargaining is costly, information is unclear, or power is unequal.

When does Coase Theorem matter?

Coase Theorem is one of the 40 mental models for fixing problems, the situations where you ask: Why does this keep going wrong, and how do I fix it for good? Within that, it belongs to “Rewards and rules”, alongside Cap and Trade, Goodhart’s Law and Government Failure.

What is an example of Coase Theorem?

Two stories show it at work: The doctor and the confectioner (1879) and American Electric Power (2002). Both are told in full in The Mental Models Daily Almanac, which has two stories for each of its 365 models.

Which mental models are related to Coase Theorem?

Tragedy of the Commons, Zero-Sum vs Win-Win and Market Failure. Coase Theorem itself comes from economics.