For a whole economy, does planned expenditure on newly-produced goods necessarily equal planned income from the sale of newly-produced goods? That's what I mean by "Say's Law" in this context. Say's Law is wrong, and the fact that it is wrong is really important for macroeconomics. But it's not obvious why Say's Law is wrong. […]

Via Casey Mulligan and Karl Smith, here is John Cochrane's response to Paul Krugman. It's a very good response. But there is one part where John Cochrane is definitely wrong. It's small, but important. And it's all about Say's Law, and the crucial difference between a monetary exchange and a barter economy.

That's the question we ought to be asking right now, but I haven't seen anyone ask it, let alone answer it. I don't know the answer, but I do know it's the right question to ask.

Could monetary policy have caused the recent rise in levels of debt? The obvious answer is that loose monetary policy lowers interest rates, which causes people to want to borrow and spend more, and so go deeper into debt. That answer is both obvious and wrong, as I explained in a previous post. Low interest […]

Updated below. I have heard the argument so many times: "Low interest rates caused people to want to borrow and spend, and that's what caused debt to increase". It's such a simple and obvious explanation; only someone with a PhD in economics could fail to understand it. Unfortunately it's also an explanation that makes no […]