MMT — the key insights

7 Jun, 2024 at 10:56 | Posted in Economics | 3 Comments

As has become abundantly clear during the last couple of years, it is obvious that most mainstream economists seem to think that Modern Monetary Theory is something new that some wild heterodox economic cranks have come up with. That is actually very telling about the total lack of knowledge of their own discipline’s history these modern mainstream guys like Summers, Rogoff and Krugman have.

New? Cranks? Reading one of the founders of neoclassical economics, Knut Wicksell, and what he wrote in 1898 on ‘pure credit systems’ in Interest and Prices (Geldzins und Güterpreise) soon makes the delusion go away:

It is possible to go even further. There is no real need for any money at all if a payment between two customers can be accomplished by simply transferring the appropriate sum of money in the books of the bank …

A pure credit system has not yet … been completely developed in this form. But here and there it is to be found in the somewhat different guise of the banknote system …

We intend therefore​, as a basis for the following discussion, to imagine a state of affairs in which money does not actually circulate at all, neither in the form of coin … nor in the form of notes, but where all domestic payments are effected by means of the Giro system and bookkeeping transfers. A thorough analysis of this purely imaginary case seems to me to beworthwhile​e, for it provides a precise antithesis to the equally imaginary​ case of a pure cash system, in which credit plays no part whatever [the exact equivalent of the often used neoclassical model assumption of ‘cash in advance’ – LPS] …

For the sake of simplicity, let us then assume that the whole monetary system of a country is in the hands of a single credit institution, provided with an adequate number of branches, at which each independent economic individual keeps an account on which he can draw cheques.

What Modern Monetary Theory (MMT) basically does is more or less what Wicksell tried to do more than a hundred years ago. The difference is that today the ‘pure credit economy’ is a reality and not just a theoretical curiosity — MMT describes a fiat currency system that almost every country in the world is operating under.

In modern times legal currencies are totally based on fiat. Currencies no longer have intrinsic value (such as gold and silver). What gives them value is basically the simple fact that you have to pay your taxes with them. That also enables governments to run a kind of monopoly business where they never can run out of money. A fortiori, spending becomes the prime mover and taxing and borrowing is degraded to following acts. If we have a depression, the solution, then, is not austerity. It is spending. Budget deficits are not a major problem since fiat money means that governments can always make more of them.​

In the mainstream economist’s world, we don’t need fiscal policy other than when interest rates hit their lower bound (ZLB). In normal times monetary policy suffices. The central banks simply adjust the interest rate to achieve full employment without inflation. If governments in that situation take on larger budget deficits, these tend to crowd out private spending and the interest rates get higher.

What mainstream economists have in mind when they argue this way, is nothing but a version of Say’s law, basically saying that savings have to equal investments and that if the state increases investments, then private investments have to come down (‘crowding out’). As an accounting identity, there is, of course, nothing to say about the law, but as such, it is also totally uninteresting from an economic point of view. What happens when ex-ante savings and investments differ, is that we basically get output adjustments. GDP changes and so makes saving and investments equal ex-post. And this, nota bene, says nothing at all about the success or failure of fiscal policies!

For the benefit of our latter-day​ ‘New Keynesian’ mainstream economists, let’s see what a real Keynesian economist has to say about crowding out and government deficits:

Fallacy 3
Government borrowing is supposed to “crowd out” private investment.

The current reality is that on the contrary, the expenditure of the borrowed funds (unlike the expenditure of tax revenues) will generate added disposable income, enhance the demand for the products of private industry, and make private investment more profitable. As long as there are plenty of idle resources lying around, and monetary authorities behave sensibly, (instead of trying to counter the supposedly inflationary effect of the deficit) those with a prospect for profitable investment can be enabled to obtain financing. Under these circumstances, each additional dollar of deficit will in the medium long run induce two or more additional dollars of private investment. The capital created is an increment to someone’s wealth and ipso facto someone’s saving. “Supply creates its own demand” fails as soon as some of the income generated by the supply is saved, but investment does create its own saving, and more. Any crowding out that may occur is the result, not of underlying economic reality, but of inappropriate restrictive reactions on the part of a monetary authority in response to the deficit.

William Vickrey Fifteen Fatal Fallacies of Financial Fundamentalism

It is true that MMT rejects the traditional Phillips curve inflation-unemployment trade-off and has a less positive evaluation of traditional policy measures to reach full employment. Instead of a general increase in aggregate demand, it usually prefers more ‘structural’ and directed demand measures with less risk of producing increased inflation. At full employment, deficit spending will often be inflationary, but that is not what should decide the fiscal position of the government. The size of public debt and deficits is not — as already Abba Lerner argued with his ‘functional finance’ theory in the 1940s — a policy objective. The size of public debt and deficits are what they are when we try to fulfil our basic economic objectives — full employment and price stability.

That governments can spend whatever amount of money they want is a fact. That does not mean that MMT says they ought to — that’s something our politicians have to decide. No MMTer denies that too much government spending can be inflationary. What is questioned is that government deficits necessarily is inflationary.