One of Paul Krugman’s favorite tactics is to assert that all he’s doing is channeling the time-honored lessons of Economics 101 — pre-empting dissent with the implication that any dissenter must be either an ignoramus or a radical. (Journalistic honesty compels me to acknowledge that I might have employed this rhetorical tactic once or twice myself over the years.)
It’s interesting, then, to take note of how very far his central arguments actually deviate from Economics 101. Here’s what he said last week on his blog:
Mulligan and others keep emphasizing examples of individual groups that have managed to gain jobs by cutting wages or offering other attractions to would-be employers. They then assert that these examples tell us what would be needed to expand overall employment.
The point, of course, is that all such arguments amount to committing the fallacy of composition…The essence of macroeconomics is understanding why such things are a fallacy, why what happens if one group does something is not at all what happens when everyone does it.
But you see, here’s the thing: According to the standard Economics 101 version of the sticky-wage Keynesian model, this is a case where what happens if one group does something is exactly the same as what happens when everyone does it. According to that model, as long as wages continue to fall, firms will continue to move along their labor demand curves until we reach full employment.