Some further thoughts inspired by the welcome hatred of the usual suspects toward yours truly. One quite common statement among the Austrianish horde is something along the lines of “It’s ridiculous to imagine, as Krugman does, that you can create real wealth by printing more pieces of paper.”

Well, it may be ridiculous, but it’s also true, under certain conditions — namely, when the economy is suffering from inadequate demand. And you don’t have to use highly abstruse reasoning to see this, either; all you need to do is think in terms of some kind of model, not necessarily of the mathematical kind. The whole point of the true story of the baby-sitting coop, which brings it down to a human scale, is that it’s quite possible for economies to get into a snarl that can be solved by printing more money, or having the government spend more.

I know that this is a conclusion many people hate. They really, really want to believe that bad things must have good causes — that if you are suffering from high unemployment and low output, it must be because there is something deeply wrong, probably the fault of liberals. But what was deeply wrong with the US economy in late 2008 that wasn’t true of the US economy in late 2007? Recessions happen, and any halfway plausible story about how they happen is likely to suggest that non-fundamental government interventions, like printing money, can make things better.

It’s important to emphasize the conditionality here. The haters love to claim that people like me view more demand, more money printing, as the solution to all problems. But of course that’s not true. Aggregate demand won’t solve a problem of low productivity, or inadequate productive capacity, or for that matter extreme inequality due to technology or market power. But it can solve certain problems, which happen to be the problems we have now.