Which economist developed the theory of comparative advantage?

David Ricardo developed the theory of comparative advantage. He published its classic formulation in 1817 in On the Principles of Political Economy and Taxation.

The theory says countries can gain from trade by specializing in goods they produce at lower opportunity cost, even when one country is more efficient at producing every good. Ricardo illustrated the idea with England and Portugal producing cloth and wine.

Comparative advantage differs from absolute advantage. Adam Smith is associated with absolute advantage, which compares productivity directly; Ricardo’s insight compares what must be given up to produce something else. John Stuart Mill later refined the theory and helped popularize its terminology.

Ricardo’s argument supported freer trade and challenged protectionist thinking during Britain’s Corn Law debates. Modern trade theory has expanded his simple model to include technology, capital, labor, economies of scale, and distributional effects.