and instead I was teaching him first-grade arithmetic That particular confusion is more common than one might expect. But even at a somewhat higher level, there are, I believe, at least three implicit assumptions that underlie the most basic ricardian model, assumptions that are justified by the whole fabric of economic understanding but are not at all obvious to non-economists. here they are Wages are determined in a national labor market: The basic Ricardian model envisages a single factor, labor, which can move freely between industries. When one tries to talk about trade with laymen, however, one at least sometimes realizes that they do not think about things that way at all They think about steelworkers, textile workers, and so on; there is no such thing as a national labor market. It does not occur to them that the wages earned in one industry are largely determined by the wages similar workers are earning in other industries. This has several consequences. First, unless it is carefully explained, the standard demonstration of the gains from trade in a Ricardian model workers can earn more by moving into the industries in which you have a comparative advantage simply fails to register with lay intellectuals. Their picture is of aircraft workers gaining and textile workers losing, and the idea that it is useful even for the sake of argument to imagine that workers can move from one industry to the other is foreign to them. Second, the link between productivity and wages is thoroughly misunderstood. Non-economists typically think that wages should reflect productivity at the level of the individual company. So if Xerox manages to increase its productivity 20 percent, it should raise the wages it pays by the same amount; if overall manufacturing productivity has risen 30 percent, the real wages of manufacturing workers should have risen 30 percent, even if service productivity has been stagnant; if this doesn't happen, it is a sign that something has gone wrong. In other words, my criticism of Michael Lind would baffle many non- economists Associated with this problem is the misunderstanding of what international trade should do to wage rates. It is a fact that some Bangladeshi apparel factories manage to achieve labor productivity close to half those of comparable installations in the United States, although overall Bangladeshi manufacturing productivity is probably only about 5 percent of the US level. Non-economists find it extremely disturbing and puzzling that wages in those productive factories are only 10 percent of US standards Finally, and most importantly, it is not obvious to non-economists that wages are endogenous Someone like Goldsmith looks at Vietnam and asks, "what would happen if people who work for such low wages manage to achieve Western productivity? The economist's answer is, "if they achieve Western productivity, they will be paid Western wages"--as has in fact happened in Japan But to the non-economist this conclusion is neither natural nor plausible (And he is likely to offer those Bangladeshi factories as a counterexample, missing the distinction between factory-level and national-level productivity) Constant employment is a reasonable approximation: The standard textbook version of the indian model as in both countries. But in reality unemployment constantly a concern of economic policy - so why is this the usual assumption? There are two answers. One-the answer that ricardo would have given -is that international trade is a long-run issue, and that in the long run the economy has a natural self-correcting tendency to return to full employment. The other, more modern answer is that countries have central banks, which try to stabilize employment around the nairu; so that it makes sense to think of the Federal reserve andand instead I was teaching him first-grade arithmetic. That particular confusion is more common than one might expect. But even at a somewhat higher level, there are, I believe, at least three implicit assumptions that underlie the most basic Ricardian model, assumptions that are justified by the whole fabric of economic understanding but are not at all obvious to non-economists. Here they are: - Wages are determined in a national labor market: The basic Ricardian model envisages a single factor, labor, which can move freely between industries. When one tries to talk about trade with laymen, however, one at least sometimes realizes that they do not think about things that way at all. They think about steelworkers, textile workers, and so on; there is no such thing as a national labor market. It does not occur to them that the wages earned in one industry are largely determined by the wages similar workers are earning in other industries. This has several consequences. First, unless it is carefully explained, the standard demonstration of the gains from trade in a Ricardian model -- workers can earn more by moving into the industries in which you have a comparative advantage -- simply fails to register with lay intellectuals. Their picture is of aircraft workers gaining and textile workers losing, and the idea that it is useful even for the sake of argument to imagine that workers can move from one industry to the other is foreign to them. Second, the link between productivity and wages is thoroughly misunderstood. Non-economists typically think that wages should reflect productivity at the level of the individual company. So if Xerox manages to increase its productivity 20 percent, it should raise the wages it pays by the same amount; if overall manufacturing productivity has risen 30 percent, the real wages of manufacturing workers should have risen 30 percent, even if service productivity has been stagnant; if this doesn't happen, it is a sign that something has gone wrong. In other words, my criticism of Michael Lind would baffle many non￾economists. Associated with this problem is the misunderstanding of what international trade should do to wage rates. It is a fact that some Bangladeshi apparel factories manage to achieve labor productivity close to half those of comparable installations in the United States, although overall Bangladeshi manufacturing productivity is probably only about 5 percent of the US level. Non-economists find it extremely disturbing and puzzling that wages in those productive factories are only 10 percent of US standards. Finally, and most importantly, it is not obvious to non-economists that wages are endogenous. Someone like Goldsmith looks at Vietnam and asks, "what would happen if people who work for such low wages manage to achieve Western productivity?" The economist's answer is, "if they achieve Western productivity, they will be paid Western wages" -- as has in fact happened in Japan. But to the non-economist this conclusion is neither natural nor plausible. (And he is likely to offer those Bangladeshi factories as a counterexample, missing the distinction between factory-level and national-level productivity). - Constant employment is a reasonable approximation: The standard textbook version of the Ricardian model assumes full employment in both countries. But in reality unemployment is constantly a concern of economic policy -- so why is this the usual assumption? There are two answers. One -- the answer that Ricardo would have given -- is that international trade is a long-run issue, and that in the long run the economy has a natural self-correcting tendency to return to full employment. The other, more modern answer is that countries have central banks, which try to stabilize employment around the NAIRU; so that it makes sense to think of the Federal Reserve and