Excellent profile of Paul Krugman in the New Yorker by Larrisa MacFarquhar. It is long and interesting. A few excerpts below the fold. This is a must read if you have even a passing interest in economics. Economics is about people and it is done by people. Among contemporary economists, Krugman is as good as they come.
Krugman explained that he’d become an economist because of science fiction. When he was a boy, he’d read Isaac Asimov’s “Foundation” trilogy and become obsessed with the central character, Hari Seldon. Seldon was a “psychohistorian”—a scientist with such a precise understanding of the mechanics of society that he could predict the course of events thousands of years into the future and save mankind from centuries of barbarism. He couldn’t predict individual behavior—that was too hard—but it didn’t matter, because history was determined not by individuals but by laws and hidden forces. “If you read other genres of fiction, you can learn about the way people are and the way society is,” Krugman said to the audience, “but you don’t get very much thinking about why are things the way they are, or what might make them different. What would happen if ?”
. . .
“What does it mean to do economics?” Krugman asked on the stage in Montreal. “Economics is really about two stories. One is the story of the old economist and younger economist walking down the street, and the younger economist says, ‘Look, there’s a hundred-dollar bill,’ and the older one says, ‘Nonsense, if it was there somebody would have picked it up already.’ So sometimes you do find hundred-dollar bills lying on the street, but not often—generally people respond to opportunities. The other is the Yogi Berra line ‘Nobody goes to Coney Island anymore; it’s too crowded.’ That’s the idea that things tend to settle into some kind of equilibrium where what people expect is in line with what they actually encounter.”
. . .
Krugman wrote his thesis on exchange rates, but another class, on international trade, inspired him. “There was this kind of platonic beauty to the whole thing,” he says. “I remember going through the two-by-two-by-two model—two goods, two countries, two factors of production. The way all these pieces fitted together into a Swiss-watch-like mechanism was beautiful. I loved it.” The traditional theory of international trade, first formulated by the British economist David Ricardo, two hundred years ago, explained trade by comparative advantage: a country exported the goods that it could produce most cheaply, owing to whatever advantages it possessed—cheap labor, climate, technological expertise, and so on. It followed from this theory that countries that were the most dissimilar should do the most trade—countries in the Third World dispatching labor-intensive goods to the First World, the First World selling technology- or capital-intensive goods in return. In the years following the Second World War, however, economists had noticed that much international trade didn’t follow this pattern at all. There was a large amount of trade between countries whose economies were extremely similar, and these countries traded goods that were virtually identical: Germany sold BMWs to Sweden and Sweden sold Volvos to Germany. People had speculated about why this should be so, but nobody had come up with a model that explained it in a rigorous manner.
Krugman realized that trade took place not only because countries were different but also because there were advantages to specialization. If one country was the first to begin manufacturing airplanes, say, it might accumulate an advantage in economies of scale so large that it would be difficult for another country to break into the industry later on, even though there might not be anything about the first country that made it particularly well suited to airplane-making. But why would countries trade goods that were almost the same? Because consumers like to have a choice, and, as Avinash Dixit and Joseph Stiglitz had pointed out a few years earlier, the same logic of increasing returns to scale that Krugman had identified as an essential dynamic in trade could apply to a single brand as well as to a whole industry. Krugman presented his theory to the world in the form of a paper at the National Bureau of Economic Research in July, 1979. “The hour and a half in which I presented that paper was the best ninety minutes of my life,” he wrote later. “There’s a corny scene in the movie ‘Coal Miner’s Daughter,’ in which the young Loretta Lynn performs for the first time in a noisy bar, and little by little everyone gets quiet and starts to listen to her singing. Well, that’s what it felt like: I had, all at once, made it.”
One implication of Krugman’s theory was that, contrary to economic orthodoxy, industrial policy might have its benefits. If the location of a new industry was essentially arbitrary, then a government, by subsidizing and protecting its emergence, could enable it to gain such a lasting advantage that other countries would find it difficult to catch up. But Krugman tried to discourage industrial strategists who cited him. For, while in principle industrial policy could be helpful, in practice, he believed, it was so difficult to determine which industry should receive government help, at the expense of all the others—so difficult to predict an industry’s future, and so difficult to determine merit when powerful interests would be trying to influence that determination—that in the end industrial policy would be likely to benefit mostly the owners of a few businesses and hurt everybody else. (Industrial strategists were not convinced. “You have the cases of Japan, Korea, Brazil, China, and, to some extent, France, and the counterfactual—let’s imagine that they didn’t have an industrial policy, would they have produced the same amount of growth?—is unimaginable,” Robert Kuttner, the co-founder and co-editor of The American Prospect, says. “But to be a conventional academic economist you almost have to swear an oath that governments can’t outguess markets in the allocation of capital.”)
Later on, Krugman became interested in economic geography, in the related question of why there were regional specialties—why, in the United States, for instance, were cars produced in Detroit, carpets in Dalton, Georgia, jewelry in Providence, and chips in Silicon Valley? Again, the answer turned out to be history and accident. Once an industry started up in one place, for whatever reason (the carpet industry in Dalton appears to have its origin in a local teen-ager who in 1895 made a tufted bedspread as a wedding present), local workers became trained in its methods, skilled workers from elsewhere moved there, and related businesses sprang up close by. Then, as more skilled labor became available, the industry could grow and benefit from economies of scale. Soon, as long as it didn’t cost too much to transport the industry’s products, the advantages of the place would be such that it would be impractical for someone to open up a similar business anywhere else. Many economists found the idea that economic geography could be so arbitrary “deeply disturbing and troubling,” Krugman wrote, but he found it exciting.
Again, as in his trade theory, it was not so much his idea that was significant as the translation of the idea into mathematical language. “I explained this basic idea”—of economic geography—“to a non-economist friend,” Krugman wrote, “who replied in some dismay, ‘Isn’t that pretty obvious?’ And of course it is.” Yet, because it had not been well modelled, the idea had been disregarded by economists for years. Krugman began to realize that in the previous few decades economic knowledge that had not been translated into models had been effectively lost, because economists didn’t know what to do with it. His friend Craig Murphy, a political scientist at Wellesley, had a collection of antique maps of Africa, and he told Krugman that a similar thing had happened in cartography. Sixteenth-century maps of Africa were misleading in all kinds of ways, but they contained quite a bit of information about the continent’s interior—the River Niger, Timbuktu. Two centuries later, mapmaking had become much more accurate, but the interior of Africa had become a blank. As standards for what counted as a mappable fact rose, knowledge that didn’t meet those standards—secondhand travellers’ reports, guesses hazarded without compasses or sextants—was discarded and lost. Eventually, the higher standards paid off—by the nineteenth century the maps were filled in again—but for a while the sharpening of technique caused loss as well as gain.
Go read it all. (Hat tip: Rajan Parrikar.)