Externalities and the Limits of Pigovian Policies

Pigovian policy is developed in economic theory as an efficient resolution to externality problems. The use of this type of policy to resolve real-world externality problems, including climate change in the form of carbon taxes, assumes that the Pigovian policy result derived in theory holds in the real world. By examining the bridging conditions from theory to the real world, I argue that this assumption holds only in an ambiguously defined subset of externalities. It is thus unclear when Pigovian policy could be coherently applied, which is problematic given its widespread use in critical policy contexts.