This weekend’s New York Times Magazine has the 7,000-word article about the state of macroeconomics that Paul Krugman has been hinting at for some time now. It’s a well-written, non-technical overview of the landscape and the position Krugman has been presenting on his blog, which for now I’ll just summarize for those who may not have the time to set aside just now.

Like many, Krugman faults the discipline for its infatuation with mathematical elegance:

“[T]he central cause of the profession’s failure was the desire for an all-encompassing, intellectually elegant approach that also gave economists a chance to show off their mathematical prowess. “Unfortunately, this romanticized and sanitized vision of the economy led most economists to ignore all the things that can go wrong. They turned a blind eye to the limitations of human rationality that often lead to bubbles and busts; to the problems of institutions that run amok; to the imperfections of markets — especially financial markets — that can cause the economy’s operating system to undergo sudden, unpredictable crashes; and to the dangers created when regulators don’t believe in regulation.”

His history of post-Depression macroeconomics goes through roughly three phases: Keynesianism; Milton Friedman and monetarism, which, he argues, was relatively moderate compared to the positions of some of his self-styled followers; and the period from the 1980s until 2007, which he describes as the conflict between the Saltwater (coastal, pragmatic, New Keynesian) economists and the Freshwater (inland, efficient markets, neo-classicist) economists. According to Krugman, these two schools had differences on a theoretical level, but those differences were papered over by practical agreement on government policy: namely, monetary policy was superior to fiscal policy at managing the economy.

This false peace was exploded during the financial crisis by the zero bound, something Krugman has invoked often. The agreed-upon way to stimulate the economy in a recession is to lower interest rates. When interest rates hit zero, they can’t be lowered anymore (rather than lend you money and expect to get less back in the future, I should put it under my mattress), and then the policy question is what if anything else should be done. This provoked the fallout between people who favored the stimulus as a way of propping up demand and those who thought that for theoretical reasons a stimulus could not possibly have any positive impact.

In addition, Krugman argues, the two sides shared the same desire to represent the world using elegant mathematical models: “But the New Keynesian models that have come to dominate teaching and research assume that people are perfectly rational and financial markets are perfectly efficient.” Instead, we need to look to behavioral finance and behavioral economics, which has just gone from a hot fad in economics to the bandwagon to end all bandwagons. Krugman mentions Larry Summers’s “There Are IDIOTS” paper, which must now be the world’s most-cited-although-unpublished article, Robert Shiller, Andrei Schleifer, and Robert Vishny in particular.

This is from Krugman’s conclusion:

“So here’s what I think economists have to do. First, they have to face up to the inconvenient reality that financial markets fall far short of perfection, that they are subject to extraordinary delusions and the madness of crowds. Second, they have to admit — and this will be very hard for the people who giggled and whispered over Keynes — that Keynesian economics remains the best framework we have for making sense of recessions and depressions. Third, they’ll have to do their best to incorporate the realities of finance into macroeconomics.”

In other words, the world is messy and people are irrational, and as a result the world breaks down occasionally.

The field of economics has been going on a massive land-grab over the past few decades. It’s ironic that the area it seems to understand the least well is how an overall economy functions.

By James Kwak