Soros is particularly unenthusiastic about British assets. With the sharp housing and property downturn now underway, this is not surprising. But share prices in London, like those in New York, are only off by about 10 to 15 per cent from their peaks. By contrast, ­between May 1972 and December 1974, the Financial Times index of industrial ordinary shares dropped from over 530 to under 150, or by more than 70 per cent. If Soros’s jeremiads about the worst financial crisis since the Great Depression were to prove correct in the British case, the London stock market would have to fall by another 60 per cent. Does he really believe that will happen?

Perhaps by the phrase “financial crisis” Soros understands a broader crisis in the economy, with severe setbacks in inflation and output. On inflation, Soros’s claims just do not stack up. At the most grisly point in the 1974 downturn, inflation in the Group of ­Seven industrial countries approached 15 per cent, and in 1980 it went well above 10 per cent. By contrast, over the last five years, the average inflation rate has been between two and 2.5 per cent with negligible variation. It is true that the US has recorded much worse inflation numbers than the average, while the recent surges in the oil price may take the G7 through four per cent later in 2008. But even if the four per cent figure were to be breached in several countries, that would still be an ­excellent result by the standards of the 1970s and 1980s.

What about output? On this topic, Soros appears to be in good company, since the April World Economic Outlook from the International Monetary Fund contains some phrases similar to his. The IMF forecast is that world output will expand in 2008 by 3.7 per cent. According to its economic counsellor, Simon Johnson, the 3.7 per cent growth rate “represents a pronounced slowdown” relative to 4.9 per cent in 2007.

No doubt Soros and the IMF’s economic counsellor are great authorities, but might one sheepishly suggest they are not using the right terms? A change from 4.9 per cent to 3.7 per cent can be viewed in different ways. As a change in the growth rate of output, it amounts to a drop of almost a quarter. A drop of a quarter in a world growth forecast sounds pretty horrible and, as a way of encouraging reader interest, it is just right for a newspaper headline. If the level of world output were ­indeed at risk of falling a quarter in 2008, comparisons with the Great Depression would be justified.