One day, the 188 members of the International Monetary Fund (IMF) will have to decide what is to be done with this difficult child of Bretton Woods and the post-war world.

There are signs, more obvious with each passing year, of a personality disorder.

Sometimes the world is treated to the old, unforgiving IMF, the ideologue of market reform that punishes and rewards, always inspired by the latest orthodoxy among its biggest shareholders. Facts are eloquent: between them, 158 small countries have 23.59 per cent of the votes in the fund; the United States has 16.75 per cent, Germany 5.81 per cent, the United Kingdom 4.29 per cent.

Now and then, nevertheless, another IMF is glimpsed. This is the fund, given voice by its analysts and economists, that describes the world it sees, that tells George Osborne his austerity programme is simplistic and counter-productive. On the eve of the Greek referendum, this IMF has made an extraordinary intervention.

Until this week, the fund was part of the troika, along with the European Central Bank (ECB) and the European Union, that refused to budge over Greek external debts - mostly owed to the three - unless Greece continued to submit to "reform" and austerity. It didn't matter that Greece was back in recession, that its debts were actually rising, or that its last hopes for growth were being extinguished.

In fact, it appeared not to matter that the IMF had been charging 3.5 per cent on the €31 billion it advanced to Greece. The rate was higher than anything the Europeans were asking. According to the Jubilee Debt Campaign, the fund has made €2.5bn more than its costs from Greece since 2010. Yet the latest crisis began when Greece "defaulted" - technically, "fell into arrears" - on a €1.5bn IMF payment on 30 June.

Now the fund shows another face. Whipping the Greeks into line might count as a tactic pour encourager les autres. It might satisfy the schwarze null obsession, the zero budget deficit decreed by German law. It might enable the EU technocrats to get rid of the elected government of Alexis Tsipras and install another obedient suit. Would it solve the Greek problem?

The IMF's analysts think not. The diagnosis is this: Greece needs a minimum of €60bn over the next three years; it needs a two-decade grace period before debt repayments can be contemplated; and it should not be obliged to think about final payments until 2055. In the corporate world, that would be called a sane restructuring plan.

It raises two questions. What have the last five years been about, then, for Greece and for Europe? What does the IMF prognosis suggest, if not that austerity, by-the-book reform, the fire-sale of assets, and mass suffering, are stupid as well as cruel? The technocrats have been at this for half a decade with their prescriptions and sneers. Now some of their number say it's all been for nothing.

Obviously enough, this raises questions for Europe, and for Germany above all. First, there is an issue of democracy. The decision by the ECB to suspend most credit to Greek banks was an obvious attempt to force the Tsipras government into a corner. The declaration by Chancellor Angela Merkel that she would refuse to talk about a bailout extension before tomorrow's referendum was close to blatant. With dutiful echoes from other EU states, it told Greeks: "Vote as you are bid by us. Then bring down the Syriza-led administration."

Mr Tsipras ran that risk, of course. Headlines were always liable to say he had tested the patience of his country's benefactors, that "his bluff had been called". In reality, the Greeks have made numerous concessions to their creditors. They have, whether supporters know it or not, all but folded their hand.

For Europe's "institutions", that isn't good enough. They want it known that they were right and the Greeks wrong. They want Mr Tsipras and his colleagues gone. They want their economic prescriptions - less the "neoliberalism" of cliché than economic hygiene of the German sort - acknowledged as the only route to the future for any European country. And what part of this makes any sense whatever?

There is the cultural problem. Should Europe crush the country that was the birthplace of its ideas and art? There is a humanitarian matter. Which version of economics succeeds if 11 million people are pauperised? There is a historical issue. The heirs of the West Germany that had half its debts written off in 1954 with Greek agreement might consider Hellenic memories of war and starvation.

You could dismiss these considerations. Europe's technocrats would prefer it. But the treatment of Greece is a bad advert for the European ideal, and for German economic rigour. Since only dishonest fools allowed Greece into the eurozone, what does the spectacle of those fools punishing Greece say to people around Europe? Is this really what is meant by "ever-closer union"?

Or consider things in terms in German virtue. What lesson is being imposed on the Greeks? That each eurozone economy must be run as a tight ship, that debt is always to be abhorred, that budgets must always balance? Try it. If every last eurozone economy became strong, the euro would be a mighty currency. That would make imports cheap and exports dear. How would that work out for export-led Germany?

The IMF intervention says that all of this is beside the point. Five years of assaults on Greek government spending have left the country as badly off - arguably worse off - than it was before the first 2010 bail-out. The austerity prescription is flawed in its fundamentals. What has happened to Greece is what happens when you asphyxiate an economy, immiserate a population, direct "aid" (loans) to banks, and decide to repeat every mistake.

Those who run the eurozone have a final sanction. Having acquired the habit of making a bad situation worse, they have let it be known - some with relish - that if feckless Greek left-wingers persist with their intransigence their country will be forced out of the single currency. Since both people and government are deeply attached to the European ideal, and to the euro, this is regarded as a handy club on the eve of a referendum.

There are plenty of "Grexit" headlines around. Neither the attached copy nor the footage will point you to a single founding European treaty containing the mechanism by which a country can be expelled from the euro. There isn't one. There are, however, an estimated €48bn in notes and coins in Greek hands. Come what may, the cash remains a liability for European institutions.

Since no treaty covers Grexit, two possibilities follow. Either life is made still more hellish for ordinary Greeks to force them to quit the euro, or treaty amendments are negotiated with Greece, that EU member. Athens could set a price: €48bn would be a place to start.

The rational alternative, as the IMF wonks hint, is an orderly process of debt restructuring. It's a Greek notion, just at the moment. Debt forgiveness, that offence to German tradition, would get the job done sooner.