Mainstream economics has been a disaster, especially since the crash of 2007-08. It wasn’t able to predict the onset of the crisis. It didn’t even include the possibility of such a crisis. And it certainly hasn’t been a reliable guide to getting out of the crisis.
And yet economist after economist has been stepping forward—even on the liberal side of things—to try to convince us that things are pretty much OK in the land of mainstream economics.
Just the other day, Paul Krugman tried to convince us that, leaving aside the failure to predict the crisis or even envisioning the possibility of a crisis occurring, mainstream models “did a pretty good job of predicting how things would play out in the aftermath.” The problem, for Krugman, all comes down to the “bad behavior” of some economists who have been more interested in defending partisan turf than in getting things right.
Now, Mark Thoma wants to argue that the macroeconomic models—including the “dynamic stochastic general equilibrium” models that have become the stock-in-trade of mainstream macroeconomics for the past couple of decades—are just fine. The problem, as Thoma sees it, is not with the theory or the models but with the questions economists have been asking.
What neither Krugman nor Thoma wants to admit is those very same models—hydraulic IS-LM in the case of Krugman, the rational expectations, dynamic optimizing, and representative agents of DSGE—actually direct the behavior of economists and delimit the questions they can ask. Those models are so many theoretical lenses on the world, which determine how the economists who use them interpret the world.
I understand: Krugman and Thoma desperately want to keep the precious baby. But that also means we’re stuck with the increasingly dirty bathwater.