Friday, November 26, 2010

"The Instability of Moderation"

Some essential Krugman today. You may not agree that we've entered the Dark Age of macroeconomics but Krugman makes a good case for how and why things got so bad:

The brand of economics I use in my daily work – the brand that I still consider by far the most reasonable approach out there – was largely established by Paul Samuelson back in 1948, when he published the first edition of his classic textbook. It’s an approach that combines the grand tradition of microeconomics, with its emphasis on how the invisible hand leads to generally desirable outcomes, with Keynesian macroeconomics, which emphasizes the way the economy can develop magneto trouble, requiring policy intervention. In the Samuelsonian synthesis, one must count on the government to ensure more or less full employment; only once that can be taken as given do the usual virtues of free markets come to the fore.

It’s a deeply reasonable approach – but it’s also intellectually unstable. For it requires some strategic inconsistency in how you think about the economy. When you’re doing micro, you assume rational individuals and rapidly clearing markets; when you’re doing macro, frictions and ad hoc behavioral assumptions are essential.

So what? Inconsistency in the pursuit of useful guidance is no vice. The map is not the territory, and it’s OK to use different kinds of maps depending on what you’re trying to accomplish: if you’re driving, a road map suffices, if you’re going hiking, you really need a topo.

But economists were bound to push at the dividing line between micro and macro – which in practice has meant trying to make macro more like micro, basing more and more of it on optimization and market-clearing. And if the attempts to provide “microfoundations” fell short? Well, given human propensities, plus the law of diminishing disciples, it was probably inevitable that a substantial part of the economics profession would simply assume away the realities of the business cycle, because they didn’t fit the models.

The result was what I’ve called the Dark Age of macroeconomics, in which large numbers of economists literally knew nothing of the hard-won insights of the 30s and 40s – and, of course, went into spasms of rage when their ignorance was pointed out.

Political instability

It’s possible to be both a conservative and a Keynesian; after all, Keynes himself described his work as “moderately conservative in its implications.” But in practice, conservatives have always tended to view the assertion that government has any useful role in the economy as the thin edge of a socialist wedge. When William Buckley wrote God and Man at Yale, one of his key complaints was that the Yale faculty taught – horrors! – Keynesian economics.

I’ve always considered monetarism to be, in effect, an attempt to assuage conservative political prejudices without denying macroeconomic realities. What Friedman was saying was, in effect, yes, we need policy to stabilize the economy – but we can make that policy technical and largely mechanical, we can cordon it off from everything else. Just tell the central bank to stabilize M2, and aside from that, let freedom ring!

When monetarism failed – fighting words, but you know, it really did — it was replaced by the cult of the independent central bank. Put a bunch of bankerly men in charge of the monetary base, insulate them from political pressure, and let them deal with the business cycle; meanwhile, everything else can be conducted on free-market principles.

And this worked for a while – roughly speaking from 1985 to 2007, the era of the Great Moderation. It worked in part because the political insulation of central banks also gave them more than a bit of intellectual insulation, too. If we’re living in a Dark Age of macroeconomics, central banks have been its monasteries, hoarding and studying the ancient texts lost to the rest of the world. Even as the real business cycle people took over the professional journals, to the point where it became very hard to publish models in which monetary policy, let alone fiscal policy, matters, the research departments of the Fed system continued to study counter-cyclical policy in a relatively realistic way.

But this, too, was unstable. For one thing, there was bound to be a shock, sooner or later, too big for the central bankers to handle without help from broader fiscal policy. Also, sooner or later the barbarians were going to go after the monasteries too; and as the current furor over quantitative easing shows, the invading hordes have arrived.

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