The first known statement of the principle of comparative advantage and trade appears in an article by Robert Torrens in 1815 titled Essay on the External Corn Trade. Torrens begins by describing the basic idea of absolute advantage as described by Adam Smith but goes on to suggest that the simple intuition is erroneous. He wrote,
Suppose that there are in England, unreclaimed districts, from which corn might be raised at as small an expense of labor and capital, as from the fertile plains of Poland. This being the case, and all other things the same, the person who should cultivate our unreclaimed districts, could afford to sell his produce at as cheap a rate as the cultivator of Poland: and it seems natural to conclude, that if industry were left to take its most profitable direction, capital would be employed in raising corn at home, rather than bringing it in from Poland at an equal prime cost, and at much greater expense of carriage. But this conclusion, however obvious and natural it may, at first sight, appear, might, on closer examination, be found entirely erroneous. If England should have acquired such a degree of skill in manufactures, that, with any given portion of her capital, she could prepare a quantity of cloth, for which the Polish cultivator would give a greater quantity of corn, then she could, with the same portion of capital, raise from her own soil, then, tracts of her territory, though they should be equal, nay, even though they should be superior, to the lands in Poland, will be neglected; and a part of her supply of corn will be imported from that country.
In the first part of the passage, Torrens considers a case in which the cost of producing corn, in terms of labor and capital usage, is the same in England as it is in Poland. He points out that producers could afford to sell both English and Polish corn at the same low price. However, since it would cost additional resources to transport the corn from Poland to England (expense of carriage), it makes intuitive sense that corn should be produced in England, rather than imported, since Polish corn would wind up with a higher price than English corn in the English market.
He continues by suggesting that this conclusion is erroneous. Why? Suppose England were to remove some capital (and labor) from the production of corn and move it into the production of manufactured goods. Suppose further that England trades this newly produced quantity of manufactured goods for corn with Poland. This outcome would be better for England if the amount of corn that Poland is willing to trade for the manufactured goods is greater than the amount of corn that England has given up producing. If the excess corn that Poland is willing to trade is sufficiently large, then it may be more than enough to pay for the transportation costs between the two countries. Torrens’s final point is that this trading outcome may be superior for England even if the lands of England should be superior to the lands of Poland—in other words, even if corn can be more efficiently produced in England (i.e., at lower cost) than in Poland.
This is the first explicit description of one of the major results from the theory of comparative advantage. It reflects Torrens’s understanding that a country might conceivably benefit from free trade while reducing or eliminating production of a good it is technologically superior at producing.