The principle that, if all
markets for all goods and
services in an
economy are balanced, then the market for a specific good or service must also be balanced. Walras' law is based on the idea that excess
demand and
supply in an economy must add to zero. Thus, if there is no excess demand or supply elsewhere in an economy, then there can be no excess in a given market. Walras' law contradicts the
Keynesian notion that
involuntary unemployment can exist when an economy is otherwise in equilibrium because, according to the law, the labor market must itself be balanced. Critics of the law maintain that it does not consider
financial markets and their effect on the markets for goods and services.