Today, of course, Malthus is best-remembered for his "Essay on the Principle of Population," and its argument that population grows geometrically, while food supply runs into diminishing returns, and so near-starvation was inevitable. Ricardo is best-remembered for his rigorous exposition of the principle of comparative advantage, which remains one of the most powerful non-obvious insights that economics can offer. But in their time, Malthus was what we would today call a Keynesian and Ricardo was what we might call a neoclassical economist. Indeed, John Maynard Keynes in the General Theory gives generous credit to Malthus as his predecessor for having formulated a theory of "gluts," or what we would today call recessions.
Malthus and Ricardo apparently met around 1813 in a dispute over the "corn laws," a protectionist policy of import tariffs and export subsidies that sought to benefit English farmers. Ricardo was opposed; Malthus was in favor. But in arguing it out, they jointly developed a theory of rent; a theory of how national income would be distributed among workers, merchants, and landed gentry; and thus a basis for growth theory. They wrote copious letters to each other and published pamphlets. Dorfman writes: "They labored together to understand the economic consequences of the Corn Laws. Their discussions led them to a deeper understanding of economics than anyone had attained before. But they could not agree on the substantive matter of policy."
The English economy then suffered a postwar depression after the battle of Waterloo, which led Malthus to take the Keynesian position of explaining that if saving was too high and demand too low, the economy might suffer unemployment, while Ricardo argued that overproduction could only be a temporary state of affairs. This was followed by another dispute over the ultimate source of value, in which Malthus argued for a labor-based theory of value and Ricardo argued for a cost-of-production based theory. Many more letters followed, along with copious paragraph-by-paragraph criticisms of each others' pamphlets and books. And yet Malthus and Ricardo were best friends. Dorfman writes:
"They were still at it on August 31, 1823, when Ricardo was beginning to suffer severe headaches from an abscess on his brain. On that day, Ricardo wrote Malthus a long letter, which began, "I have only a few words more to say on the subject of value, and I have done." After about two pages of careful reasoning, he concluded, "And now, my dear Malthus, I have done. Like other disputants, after much discussion we each retain our own opinions. These discussions, however, never influence our friendship; I could not like you more than I do if you agreed in opinion with me. Pray give Mrs. Ricardo's and my kind regards to Mrs. Malthus. Yours truly ..."
"Two weeks later, Ricardo was dead. At his funeral, Malthus is reported to have said, "I never loved anybody out of my own family so much. Our interchange of opinions was so unreserved, and the object after which we were both enquiring was so entirely the truth and nothing else, that I cannot but think we sooner or later must have agreed."Malthus and Ricardo laid down some challenges worth considering in one's own life. Do you go the extra distance in at least a spirit of collegiality, to explain your views? Do you try just as hard to hear validity in the criticisms of others as you do to explaining your own views? Do you leave open the possibility that your own views are only an imperfect approximation of truth, just as the views of others are an imperfect approximation of truth, so that perhaps you are searching for answers together, rather than opposing each other? Can you completely disagree but still be friends?
Here's the last word from Dorfman:
"It is as though each served as the anvil for the other's hammer, and their ideas were hammered out in their efforts to persuade each other. They were two men obsessed by a common enthusiasm, tirelessly pursuing a common goal: to understand the economy. But they did not share a common vision of the good society and thus were condemned to wrestle interminably, though remarkably fruitfully, over the roles of the social classes. Their struggles to convey to each other their views of the forces that drove their economy are an inspiring case study in both the difficulty and the possibility of human communication. These two friends, sustained by enormous affection and respect for one another, never could nullify the differences in preconception and mental style that separated them, but still could help each other attain a deeper understanding of their economy than anyone had achieved before. To do this required invincible faith in each other's candor and open-mindedness, great patience, inexhaustible good will, and unflagging civility."In the 21st century, it's useful to remember that social media snarkiness and flame wars are a choice, and other choices are possible.
David Ricardo was one of those rare people who achieved both tremendous success and lasting fame. After his family disinherited him for marrying outside his Jewish faith, Ricardo made a fortune as a stockbroker and loan broker. When he died, his estate was worth more than $100 million in today’s dollars. At age twenty-seven, after reading Adam Smith’s The Wealth of Nations, Ricardo got excited about economics. He wrote his first economics article at age thirty-seven and then spent the following fourteen years—his last ones—as a professional economist.
Ricardo first gained notice among economists over the “bullion controversy.” In 1809 he wrote that England’s inflation was the result of the Bank of England’s propensity to issue excess banknotes. In short, Ricardo was an early believer in the quantity theory of money, or what is known today as monetarism.
In his Essay on the Influence of a Low Price of Corn on the Profits of Stock (1815), Ricardo articulated what came to be known as the law of diminishing marginal returns. One of the most famous laws of economics, it holds that as more and more resources are combined in production with a fixed resource—for example, as more labor and machinery are used on a fixed amount of land—the additions to output will diminish.
Ricardo also opposed the protectionist Corn Laws, which restricted imports of wheat. In arguing for free trade, Ricardo formulated the idea of comparative costs, today called comparative advantage—a very subtle idea that is the main basis for most economists’ belief in free trade today. The idea is this: a country that trades for products it can get at lower cost from another country is better off than if it had made the products at home.
Say, for example, Poorland can produce one bottle of wine with five hours of labor and one loaf of bread with ten hours. Richland’s workers, on the other hand, are more productive. They produce a bottle of wine with three hours of labor and a loaf of bread with one hour. One might think at first that because Richland requires fewer labor hours to produce either good, it has nothing to gain from trade.
Think again. Poorland’s cost of producing wine, although higher than Richland’s in terms of hours of labor, is lower in terms of bread. For every bottle produced, Poorland gives up half of a loaf, while Richland has to give up three loaves to make a bottle of wine. Therefore, Poorland has a comparative advantage in producing wine. Similarly, for every loaf of bread it produces, Poorland gives up two bottles of wine, but Richland gives up only a third of a bottle. Therefore, Richland has a comparative advantage in producing bread.
If they exchange wine and bread one for one, Poorland can specialize in producing wine and trading some of it to Richland, and Richland can specialize in producing bread. Both Richland and Poorland will be better off than if they had not traded. By shifting, say, ten hours of labor out of producing bread, Poorland gives up the one loaf that this labor could have produced. But the reallocated labor produces two bottles of wine, which will trade for two loaves of bread. Result: trade nets Poorland one additional loaf of bread. Nor does Poorland’s gain come at Richland’s expense. Richland gains also, or else it would not trade. By shifting three hours out of producing wine, Richland cuts wine production by one bottle but increases bread production by three loaves. It trades two of these loaves for Poorland’s two bottles of wine. Richland has one more bottle of wine than it had before, and an extra loaf of bread.
These gains come, Ricardo observed, because each country specializes in producing the good for which its comparative cost is lower.
Writing a century before Paul Samuelson and other modern economists popularized the use of equations, Ricardo is still esteemed for his uncanny ability to arrive at complex conclusions without any of the mathematical tools now deemed essential. As economist David Friedman put it in his 1990 textbook, Price Theory, “The modern economist reading Ricardo’s Principles feels rather as a member of one of the Mount Everest expeditions would feel if, arriving at the top of the mountain, he encountered a hiker clad in T-shirt and tennis shoes.”
One of Ricardo’s chief contributions, arrived at without mathematical tools, is his theory of rents. Borrowing from Thomas Malthus, with whom Ricardo was closely associated but often diametrically opposed, Ricardo explained that as more land was cultivated, farmers would have to start using less productive land. But because a bushel of corn from less productive land sells for the same price as a bushel from highly productive land, tenant farmers would be willing to pay more to rent the highly productive land. Result: the landowners, not the tenant farmers, are the ones who gain from productive land. This finding has withstood the test of time. Economists use Ricardian reasoning today to explain why agricultural price supports do not help farmers per se but do make owners of farmland wealthier. Economists use similar reasoning to explain why the beneficiaries of laws that restrict the number of taxicabs are not cab drivers per se but rather those who owned the limited number of taxi medallions (licenses) when the restriction was first imposed.
1817. On the Principles of Political Economy and Taxation. In The Works and Correspondence of David Ricardo. 11 vols. Edited by Piero Sraffa, with the collaboration of M. H. Dobb. Cambridge: Cambridge University Press, 1951–1973. Available online at http://www.econlib.org/library/Ricardo/ricP.html
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