After last week's euro meeting, Spanish 10-year government bond yields fell back to 6.6pc. So that's all right then. In fact, if Spain carried on borrowing at this rate it would be set for the knacker's yard sooner than you could say Don Quixote. Finland is just as financially conservative as Germany and in contemplating euro exit, she does not bear the burden of war guilt.

The essence of the eurozone's financial problem lies in the discrepancy between northern and southern members. So why don't they just integrate their finances? Because that would mean the northern countries taking their share of the debts incurred by the southerners.

Understandably, people in the north don't like this idea. They haven't enjoyed the benefits of government largesse – why should they now suffer the pain of higher taxes or interest costs to pay for it?

Suppose the German government said: "We are going to borrow more in order to lend it to the Spanish government." The reaction would be the Teutonic equivalent of "Not on your Nellie." So if you are hell-bent on preserving the euro, somehow you have to get money flowing to the south without the north noticing. This is where the wizardry of modern finance comes in.

The solution is that the German government does not lend the money – at least, not directly. The ECB provides one alternative channel through its purchases of peripheral countries' debt.

A second comes through the euro-system's recycling of deposits which have left vulnerable countries' banking systems and built up with the Bundesbank. (This is the so-called Target-money.) A third channel is to put the money through an off-balance sheet entity. The latest version of this idea is called the European Stability Mechanism (ESM). This is partially funded by eurozone governments, but because it is able to borrow in the markets with those governments' guarantee, it is able to lend six times what they put in.

Haven't we been here before? If this lending goes wrong, the guarantees will be called and the northern eurozone governments will be up for the whole amount. German government debt is not huge but neither is it comfortably low. It is running at about 80pc of GDP. But this excludes its indirect exposure, which is rising at alarming rates. The Bundesbank's claims on other parts of the eurozone now amount to about €700bn (£550bn), or the equivalent of almost 30pc of German GDP.

So you can understand why the politicians find it difficult to come up with a "solution".

The latest Spanish deal was astonishingly vacuous. It was agreed to lend to the Spanish government €30bn of the €100bn that had already been promised. The aim is to provide the rest direct to Spanish banks, so that Spanish government debt is not increased.

But member countries are yet to agree to this. Last week's meeting merely agreed to discuss it in September. If the money goes direct to Spanish banks, they will require some common eurozone oversight. This may take a year to work out. Meanwhile, the German Constitutional Court is bothered about the legality of all this. It may not pronounce for several months.

The politicians and the markets are operating on completely different time-scales. The politicians are finally realising that they are grappling with the impossible but think they have years to play with – the markets suspect they are dealing with the unsustainable and think they have only months to decide.

As we saw with the sub-prime crisis, in the end, financial chicanery mixed with obfuscation gets you nowhere. Without growth, the peripheral countries are heading for a debt disaster.

Yet there is still no growth initiative from the eurozone authorities. They have not even agreed to discuss it in September.

What cannot be sustained won't be. Yet we cannot exactly foresee the details of future events.

I have written about the desirability of Germany leaving the euro – and the likelihood of Greece doing so. But I am now wondering whether Finland might be the first to go. She is just as financially conservative as Germany and in contemplating euro exit, she does not bear the burden of war guilt.

She is close to other Nordic countries which have done pretty well by maintaining their own currencies. And if Finland left, she would not have the problems associated with weak currencies. On the contrary, she has a triple A credit rating and her new currency would rise.

Finland has been critical before. The disintegration of the ERM in 1992 began there. Going back further, it was the Finns' bold resistance against the Red Army's assault in 1939 that persuaded Hitler that the Soviet Union would be a pushover for the Wehrmacht. It would be fitting if it was the country not of Wagner but of Sibelius that prompted the unravelling of the euro.