David Ricardo – On the Principles of Political Economy and Taxation
If Adam Smith was the first great modern economist, David Ricardo was the second. His textbook has its faults, but Ricardo plants all manner of seeds that later economists would grow into the quantity theory of money, denationalized currency, the law of one price, and the subjective theory of value, among other things.
Ricardo’s most famous contributions are to the theory of international trade and comparative advantage. On these issues, like nearly all economists, he stands almost exactly opposite President Trump.