The Accidental Theorist
All work and no play makes William Greider a dull boy.
Imagine an economy that produces only two things: hot dogs and buns. Consumers in this economy insist that every hot dog come with a bun, and vice versa. And labor is the only input to production.
OK, timeout. Before we go any further, I need to ask what you think of an essay that begins this way. Does it sound silly to you? Were you about to turn the virtual page, figuring that this couldn't be about anything important?
One of the points of this column is to illustrate a paradox: You can't do serious economics unless you are willing to be playful. Economic theory is not a collection of dictums laid down by pompous authority figures. Mainly, it is a menagerie of thought experiments--parables, if you like--that are intended to capture the logic of economic processes in a simplified way. In the end, of course, ideas must be tested against the facts. But even to know what facts are relevant, you must play with those ideas in hypothetical settings. And I use the word "play" advisedly: Innovative thinkers, in economics and other disciplines, often have a pronounced whimsical streak.
It so happens that I am about to use my hot-dog-and-bun example to talk about technology, jobs, and the future of capitalism. Readers who feel that big subjects can only be properly addressed in big books--which present big ideas, using big words--will find my intellectual style offensive. Such people imagine that when they write or quote such books, they are being profound. But more often than not, they're being profoundly foolish. And the best way to avoid such foolishness is to play around with a thought experiment or two.
So let's continue. Suppose that our economy initially employs 120 million workers, which corresponds more or less to full employment. It takes two person-days to produce either a hot dog or a bun. (Hey, realism is not the point here.) Assuming that the economy produces what consumers want, it must be producing 30 million hot dogs and 30 million buns each day; 60 million workers will be employed in each sector.
Now, suppose that improved technology allows a worker to produce a hot dog in one day rather than two. And suppose that the economy makes use of this increased productivity to increase consumption to 40 million hot dogs with buns a day. This requires some reallocation of labor, with only 40 million workers now producing hot dogs, 80 million producing buns.
Then a famous journalist arrives on the scene. He takes a look at recent history and declares that something terrible has happened: Twenty million hot-dog jobs have been destroyed. When he looks deeper into the matter, he discovers that the output of hot dogs has actually risen 33 percent, yet employment has declined 33 percent. He begins a two-year research project, touring the globe as he talks with executives, government officials, and labor leaders. The picture becomes increasingly clear to him: Supply is growing at a breakneck pace, and there just isn't enough consumer demand to go around. True, jobs are still being created in the bun sector; but soon enough the technological revolution will destroy those jobs too. Global capitalism, in short, is hurtling toward crisis. He writes up his alarming conclusions in a 473-page book; full of startling facts about the changes underway in technology and the global market; larded with phrases in Japanese, German, Chinese, and even Malay; and punctuated with occasional barbed remarks about the blinkered vision of conventional economists. The book is widely acclaimed for its erudition and sophistication, and its author becomes a lion of the talk-show circuit.
Meanwhile, economists are a bit bemused, because they can't quite understand his point. Yes, technological change has led to a shift in the industrial structure of employment. But there has been no net job loss; and there is no reason to expect such a loss in the future. After all, suppose that productivity were to double in buns as well as hot dogs. Why couldn't the economy simply take advantage of that higher productivity to raise consumption to 60 million hot dogs with buns, employing 60 million workers in each sector?
Or, to put it a different way: Productivity growth in one sector can very easily reduce employment in that sector. But to suppose that productivity growth reduces employment in the economy as a whole is a very different matter. In our hypothetical economy it is--or should be--obvious that reducing the number of workers it takes to make a hot dog reduces the number of jobs in the hot-dog sector but creates an equal number in the bun sector, and vice versa. Of course, you would never learn that from talking to hot-dog producers, no matter how many countries you visit; you might not even learn it from talking to bun manufacturers. It is an insight that you can gain only by playing with hypothetical economies--by engaging in thought experiments.
A t this point, I imagine that readers have three objections.
Paul Krugman writes a twice-weekly column for the New York Times and is professor of economics and international affairs at Princeton University. His home page contains links to many of his other articles and essays.