The Jan Hatzius interview on sectoral balances mentioned in the previous post – although has given it some popularity – has led to great confusions among economic commentators.

Here is a confused Professor from the famous institute INSEAD – Antonio Fatás on his blog.

Fatás implicitly denies that propensities to consume/save and government expenditure and taxing decisions have any impact at all on demand and hence output.

I quote from his blog. The quote includes that of Hatzius’ interview (in italics):

[Hatzius] “That’s the starting point. It’s a truism, basically. Where it goes from being a truism and an accounting identity to an economic relationship is once you recognize that cyclical impulses to the economy depend on desired changes in these sector’s financial balances. If the business sector is basically trying to reduce its financial surplus at a more rapid pace than the government is trying to reduce its deficit then you’re getting a net positive impulse to spending which then translates into stronger, higher, more income, and ultimately feeds back into spending.”

[Fatás] This paragraph is misleading (I will ignore again the fact that in an open economy things are more complex). It states (at least this is the way I read it) that growth depends on the “desired changes in these sector’s financial balance”. This is not correct. I can imagine an economy where those financial balances are not changing at all where output is growing very fast (and I can also imagine another one where output is collapsing). There is no connection between growth and these financial imbalances. As long as demand (private or public) is feeding into production and income, the private or public sector might be spending more than last year but their income is also increasing which can make the financial balance remain at the same level as before.

Jan Hatzius is discussing a model of business cycles and growth in the medium term – such as a year or two. But for Fatás, “this is not correct” and “there is no connection between growth and these financial imbalances”! He claims that demand can be feeding into production and income but doesn’t realize that a change in financial balances caused by say a change in the propensity to save or consume itself leads to changes in the source of demand.

Fatás is thinking of a situation – a type of a long run situation where the parameters in the models are not changing and there is high growth. But that does not mean “there is no connection between growth and these financial balances”. A spontaneous change in one or few parameters (such as the propensity to consume) or an exogenous change in the government expenditure changes financial balances and affects the growth rate.

But these things do not matter for him:

If we believe that we are in a situation where the output gap is large, there are unused resources and, as a result, output is determined by demand, what matters for growth is whether demand increases relative to last year and not so much the change in the desired changes in the financial balances of either the private or public sector.

Again forgetting that desired changes in the financial balances affect the sources of demand.

Somehow basic notions of the Keynesian principle of effective demand are difficult for economists to understand.