Ambrose Evans-Pritchard draws our attention to a speech by Jaime Caruana, General Manager of the Bank for International Settlements. It is indeed a quite remarkable speech — and I mean that in the worst way; it’s a perfect illustration of the way permahawks keep finding new arguments for their never-changing demand that we raise interest rates now now now.

Some background: the BIS has spent almost the whole period since the financial crisis struck calling for tighter money. Oddly, however, it keeps changing its justifications for that call. At first it was dire warnings of inflation just around the corner. Then it was financial instability. Now, with low inflation and possible deflation a growing concern, Mr. Caruana argues that (a) deflation is not so bad (b) we’re in a balance sheet slump, and that means loose money is bad.

On the first point, isn’t it quite remarkable how the BIS has slid from warning about inflation — and dismissing concerns about deflation — to saying that deflation is OK? Beyond that, the main case for arguing that deflation is OK is economic growth during the late 19th century. Is that really a good model? Just to take the most obvious point: the late 19th century was marked by rapid population growth in the “zones of recent settlement” (basically places where Europeans were moving in, displacing or wiping out the locals). In the United States, population grew 2 percent a year from 1880-1910, sustaining high investment demand. And the zones of recent settlement also offered an outlet for very large capital outflows from Europe. In other words, the global situation was conducive to a high natural real rate of interest, making mild deflation much more sustainable than in today’s world.

I’ll probably want to write more about Gilded Age deflation. But for now, let me turn to the balance-sheet thing. Mr. Caruana draws a distinction between the view that we’re suffering from inadequate aggregate demand, and what he claims is a contrasting view that the problem is too much debt; and he claims that the excess debt/balance sheet approach implies that expansionary monetary policy is unhelpful and counterproductive.

And I wonder what on earth he’s talking about.

It’s true that balance-sheet considerations were underemphasized in macroeconomics until recently. But it’s not too hard to put them into a more or less New Keynesian model — see, in particular (ahem) Eggertsson and Krugman (pdf). And what this analysis tells you is that expansionary monetary policy is more, not less, helpful than a model without balance-sheet effects would suggest, because high income and prices reduce the burden of debt.

And conversely, deflation is much worse in a debt-laden world than without, again because of its effect on the real burden. You don’t have to take my word for it — read Irving Fisher from 1933!

So how does the balance-sheet story turn into a case for tight money? I have no idea — there’s certainly no clear explanation in the Caruana speech.

By all means let’s talk about balance-sheet effects. But is it really too much to demand a model, or at least a carefully spelled-out mechanism? Right now it looks as if the BIS is claiming that balance sheets make the case for tight money because in Basel everything makes the case for tight money.