Zanimivo debato med progresivnimi makroekonomisti (neokeynesianci) in progresivnimi monetaristi (pripadniki endogene teorije denarja) o tem, ali centralne banke tiskajo denar “iz zraka” (namesto iz depozitov), o kateri je večkrat pisal Aleš Praprotnik, je dopolnila debata o tem, ali ima dolg res nevtralen učinek na povpraševanje. Zadnja debata o sekularni stagnaciji, o kateri sem pisal pred enim mesecem, je namreč razkrila tudi to, da se je ob stagnirajočih dohodkih večine prebivalstva v ZDA agregatno povpraševanje povečevalo zaradi rastočega dolga gospodinjstev.

To je zanimiv fenomen, saj bi pomenilo priznanje, da lahko ne samo vlade kreirajo dodatno povpraševanje z dodatnim javnim zadolževanjem (predvsem v kriznih razmerah) , pač pa da lahko enako delajo tudi banke z odobravanjem kreditov v “mirnih časih”. To bi zahtevalo popravke teorij. Vse lepo in prav, toda nekje vmes so baloni, ki nastopijo, če banke ekscesno posojajo. Ali drugače povedano, če v mirnih časih povpraševanje ne more rasti brez balonov, je nekaj narobe s prerazdelitvijo dohodkov. Očitno velika večina “spodaj” dobi premajhen kos kolača. In da bi to uvideli, niso potrebne nove teorije.

Spodaj je izsek iz zapisa Steva Keena, prvega govorca struje endogene teorije denarja:

“Keen then goes on to assert that lending is, by definition (at least as I understand it), an addition to aggregate demand. I guess I don’t get that at all. If I decide to cut back on my spending and stash the funds in a bank, which lends them out to someone else, this doesn’t have to represent a net increase in demand. Yes, in some (many) cases lending is associated with higher demand, because resources are being transferred to people with a higher propensity to spend; but Keen seems to be saying something else, and I’m not sure what. I think it has something to do with the notion that creating money = creating demand, but again that isn’t right in any model I understand.” (Minsky and Methodology (Wonkish), March 27, 2012)

Then earlier this month, this argument turned up in his musings about the secular stagnation hypothesis:

“Start with the point I’ve raised several times, and others have raised as well: underneath the apparent stability of the Great Moderation lurked a rapid rise in debt that is now being unwound … Debt was rising by around 2 per cent of GDP annually; that’s not going to happen in future, which a naïve calculation suggests means a reduction in demand, other things equal, of around 2 percent of GDP.” (Secular Stagnation Arithmetic, December 7, 2013)

Don’t get me wrong: I’m glad that Krugman may finally be starting to support the case that I (and some other endogenous money theorists like Michael Hudson and Dirk Bezemer) have been making for many years: that rising debt directly adds to aggregate demand. If he is, then welcome aboard. Though there’s doubt as to whether John Maynard Keynes ever uttered the words attributed to him that “when the facts change, I change my mind – what do you do sir?”, I’m happy to accept this shift in that spirit.

But I don’t want to see this change in analysis sneak under the radar either: it deserves acknowledgement as a major shift in the thinking of a major figure in contemporary economics.

It also calls for a theory in which this is possible: a theory in which an increase in debt causes a commensurate increase in demand. As Krugman put it himself back in March of 2012, the argument that rising debt directly adds to demand “has something to do with the notion that creating money = creating demand, but again that isn’t right in any model I understand.” And that’s true, because the model Krugman understood back then was the model of ‘loanable funds’, in which increasing debt can’t add much to aggregate demand, because debt simply transfers spending power from a lender to a borrower.

In a Loanable Funds universe, only if the lender is a miser and the borrower a spendthrift will demand rise all that much – and generally, mainstream economists downplay this possibility. As Ben Bernanke put it when he downplayed Irving Fisher’s Debt-Deflation Theory of Great Depressions, “Absent implausibly large differences in marginal spending propensities among the groups … pure redistributions should have no significant macro-economic effects…” (Essays on the Great Depression, 2000) And as Krugman himself put it just a year ago, “the overall level of debt makes no difference to aggregate net worth – one person’s liability is another person’s asset. It follows that the level of debt matters only if the distribution of net worth matters.” (End This Depression Now!, 2012)

Yet here we have Krugman suggesting that change in the aggregate level of debt matters in its own right, and proposing a one-for-one correspondence between the change in aggregate private debt and aggregate demand: “Debt was rising by around 2 per cent of GDP annually; that’s not going to happen in future, which a naïve calculation suggests means a reduction in demand, other things equal, of around 2 per cent of GDP.”

Have you heard the old joke that an economist is someone who, seeing that something works in practice, then says “Ah! But does it work in theory?”. I’m not going to pull that swifty here: as I noted last week, I see the role of debt adding to aggregate demand as an empirical reality that economists have to explain – not something that can’t exist unless economists have a model that explains it. But just as physics could only progress at the end of the 19th century after it had developed a model that explained the peculiar properties of ‘black-body’ radiation (see Figure 1), economics will only progress in the 21st if it can explain how and why an increase in debt adds to aggregate demand.

Vir: Steve Keen