Two things caught my attention in the last two days.

First is the claim by Roger Farmer:

The Keynesian economics of the General Theory is static.

That’s the strangest critique of the GT I have ever seen. How is the GT static? John Maynard Keynes highlighted how a fall in the propensity to consume reduces output. His mechanism was quite dynamic. He was arguing that a fall in the propensity to consume will reduce consumption and hence firms’ sales and hence production and hence employment and hence consumption and so on. Keynes did not explicitly write down a mathematical model like as done for example in the book Monetary Economics by Wynne Godley and Marc Lavoie. But his arguments were quite dynamic in nature. So was his argument about how investment creates saving. And also the Keynesian multiplier. “Stock-flow consistent” models are quite close to Keynes’ spirit.

The second is this paragraph from Michael Pettis:

… This is one of the most fundamental errors that arise from a failure to understand the balance of payments mechanisms. As I explained four years ago in an article for Foreign Policy, “it may be correct to say that the role of the dollar allows Americans to consume beyond their means, but it is just as correct, and probably more so, to say that foreign accumulations of dollars force Americans to consume beyond their means.” As counter-intuitive as it may seem at first, the US does not need foreign capital because the US savings rate is low. The US savings rate is low because it must counterbalance foreign capital inflows, and this is true out of arithmetical necessity, as I showed in a May, 2014 blog entry (link broken: archive.is link).

Oh boy! That’s confusing accounting identities with behaviour. A simple way to show how inaccurate this is by using standard Keynesian analysis. Assume US households reduce the propensity to consume. This leads to a fall in output and income and hence a fall in imports and an increase in the current account balance of payments (assuming exports are exogenous to the model). This can be seen more precisely in a stock-flow consistent model.

Pettis’ arguments are in response to Stephen Roach’s recent article on US balance of payments and I discussed that recently here.  Both Roach and Pettis are incorrect.

Balance of payments is important and in my opinion, the most important thing in Economics. Michael Pettis gets the attention because he realizes the importance of balance of payments in the economic dynamics of the world. However looked more closely, many of his arguments appear vacuous.