David Ricardo: Comparative Advantage & Economic Theories Innovator

Search Fintrev

Search our guides, reviews and glossary.

David Ricardo (1772 to 1823) was a British political economist, stockbroker and member of Parliament. He is best known for the theory of comparative advantage: two countries can both gain from trade when each specializes in the good it produces at a lower opportunity cost, even if one of them is more efficient at producing everything. His other main ideas include the theory of rent, the labor theory of value, diminishing returns in agriculture, a subsistence view of wages and the argument now called Ricardian equivalence. His 1817 book, On the Principles of Political Economy and Taxation, set out most of this work and helped make classical economics a more abstract, model-based discipline.

Early Life and Education

Ricardo was born in London in 1772 into a Sephardic Jewish family that had moved to England from the Netherlands. He was one of 17 children. His father was a stockbroker, and Ricardo began working with him at the age of 14 after a short period of schooling, including time in Amsterdam.

He did not attend university. At 21 he married Priscilla Anne Wilkinson, a Quaker, and left the Jewish faith. His family broke with him over the marriage, and he had to build his career on his own.

His interest in economics came by chance. Around 1799, while staying in Bath, he read Adam Smith’s Wealth of Nations and began studying political economy in his spare time. Smith’s influence shows throughout his work, though Ricardo often disagreed with him. He later moved in a circle that included James Mill, Jeremy Bentham and Thomas Malthus. Malthus was his closest intellectual opponent, and their long correspondence shaped both men’s thinking.

Career

Ricardo set up his own business dealing in government securities and became one of the wealthiest men in Britain. The best-known episode is the Battle of Waterloo in 1815. Ricardo held British government stock as the battle approached, and its outcome is said to have earned him about £1 million. He retired from business at around 41 and bought a country estate, Gatcombe Park in Gloucestershire.

In 1819 he bought a seat in Parliament for about £4,000, representing Portarlington, a small Irish borough. He used the House of Commons to argue for free trade, sound money and the repeal of the Corn Laws, the tariffs that protected British grain growers from imports. He died in 1823 at the age of 51.

Key Work

Comparative Advantage

Adam Smith had argued that countries gain by trading goods in which each has an absolute advantage, meaning it produces them with fewer resources. Ricardo showed that trade can benefit both sides even when one country has an absolute advantage in every good.

He used England and Portugal, cloth and wine. In his example, the labor needed to produce a fixed quantity of each good was:

Portugal is more efficient at both goods. What matters is the opportunity cost. In England, producing one unit of wine uses labor that could make 1.2 units of cloth (120 ÷ 100). In Portugal, one unit of wine costs only about 0.89 units of cloth (80 ÷ 90). Portugal gives up less cloth to make wine, so it has the comparative advantage in wine. England gives up less wine to make cloth, so it has the comparative advantage in cloth.

Suppose they trade one unit of cloth for one unit of wine (a rate chosen for illustration). England gets wine for 100 workers’ labor instead of 120. Portugal gets cloth for 80 workers’ labor instead of 90. Both countries consume more for the same total labor. That result, the “Ricardian model,” became the starting point of international trade theory.

The model rests on simplifying assumptions: two countries, two goods, labor as the only cost, labor unable to move between countries, and no transport costs. Later economists extended it and criticized it for ignoring adjustment costs to workers and industries that lose out from trade. Robert Torrens published a similar idea in 1815, but the theory is most closely associated with Ricardo’s 1817 statement of it.

The Theory of Rent

Ricardo’s theory of rent, building on work by Malthus and others, explains why landowners earn income without contributing productive effort. Land differs in fertility and location. As population grows and more food is needed, farmers must cultivate poorer land. The last plot brought into use, the “margin,” earns no rent: its output just covers the costs of labor and capital.

Better land produces more with the same inputs, and that surplus goes to the landowner as rent. Rent on any plot equals the difference between its output and the output of marginal land. Ricardo drew a pointed conclusion: high grain prices are not caused by high rents. Rents are high because grain prices are high, since high prices push cultivation onto worse land and widen the gap with better plots.

This was the economic core of his attack on the Corn Laws. By keeping out cheap foreign grain, the tariffs forced Britain onto poorer soil, raised food prices and transferred income to landlords. The Corn Laws were repealed in 1846, more than two decades after his death.

Diminishing Returns and Profits

In his 1815 Essay on the Influence of a Low Price of Corn on the Profits of Stock, Ricardo applied the law of diminishing returns to agriculture. Adding more labor and capital to a fixed amount of land raises output by smaller and smaller amounts. Combined with population growth, this meant food would grow more expensive, wages would have to rise to keep workers fed and profits would be squeezed. Ricardo feared this would slow capital accumulation and push the economy toward a stationary state. Cheap grain imports were his proposed escape.

The Labor Theory of Value

Ricardo held that the relative value of goods depends mainly on the relative quantity of labor needed to produce them, including the labor embodied in tools and machinery. Value is not set by what workers are paid. If a table takes two hours of labor and a chair one hour, a table exchanges for two chairs, whatever the wage rates involved.

Ricardo recognized problems with this rule. Goods made with more capital, or capital that takes longer to pay off, did not exchange exactly in proportion to labor. He searched for an “invariable measure of value” for the rest of his life and never settled the issue. Karl Marx later built his concept of surplus value on Ricardo’s version of the theory. Mainstream economics eventually replaced labor-based value with theories based on marginal utility and supply and demand.

Wages

Ricardo argued that the “natural price” of labor is the wage needed for workers to subsist and maintain their numbers. If wages rose above that level, population would grow (following Malthus’s population theory), labor supply would increase and wages would fall back. This view was later labeled the “iron law of wages,” a phrase coined by Ferdinand Lassalle rather than by Ricardo. Ricardo’s own position was less rigid: he allowed that subsistence depends on habits and customs, and that market wages could stay above it for long periods in a growing economy.

Money and Banking

Ricardo’s first economic writing appeared in 1809, when he was 37, as letters to The Morning Chronicle. During the Napoleonic Wars, the Bank of England had suspended the conversion of its notes into gold, and prices had risen. Ricardo argued that the Bank had issued too many notes and that this, not foreign events, explained the high price of gold. His 1810 pamphlet The High Price of Bullion made him known publicly and influenced the government’s Bullion Committee. These arguments link him to later quantity theories of money, which connect the money supply with the price level.

Ricardian Equivalence

In public finance, Ricardo considered whether it matters if a government pays for a war with taxes now or with borrowing. In theory, if taxpayers are fully rational, they will see that debt must be repaid by future taxes and will save enough today to cover them. Private saving then rises by the amount of government borrowing, and total spending is unchanged. Under this reasoning, deficit spending meant to stimulate the economy would be offset by higher private saving.

Ricardo described this logic but doubted it held in practice, because he thought people did not plan that far ahead. Robert Barro formalized the modern version in 1974, and the label came later. It remains disputed between economists who doubt fiscal stimulus and those in the tradition of John Maynard Keynes, who argue that government spending can raise output when demand is weak.

Published Works

• The High Price of Bullion, a Proof of the Depreciation of Bank Notes (1810)
• Essay on the Influence of a Low Price of Corn on the Profits of Stock (1815)
• On the Principles of Political Economy and Taxation (1817): his main book. Later editions added a chapter “On Machinery,” in which he conceded that machines could harm workers in the short run.

Legacy

Ricardo’s method may be as important as his conclusions. He reasoned from a few stripped-down assumptions to strong general results, which is how most economic models still work. Critics, including Joseph Schumpeter, called the habit of applying such abstract models directly to policy the “Ricardian vice.”

His ideas spread in several directions. Free-trade economists built on comparative advantage. Socialists drew on his labor theory of value. Land reformers such as Henry George drew on his theory of rent to argue for taxing land values. Debates over fiscal policy still turn on Ricardian equivalence.

The Bottom Line

Ricardo matters to anyone weighing trade policy, land taxes or government borrowing, since debates in all three still draw on his models. His comparative advantage result shows that specialization by opportunity cost can benefit both trading partners. His stripped-down assumptions also carry limits, from ignoring workers hurt by trade to the abstraction critics called the Ricardian vice, so his conclusions work best as a starting point for policy rather than a final answer.