On the surface, this looks like 2003 and 2004 when the previous housing, credit, commodity and equity bubbles started to inflate, helped by low nominal interest rates and a lack of inflation. There is one big difference, though. This bubble will burst sooner.
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In mid-September both measures concluded that the US stock market was overvalued by some 35 to 40 per cent. The markets have since gone up a lot more than the moving average of earnings. You can do the maths.
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We could be in for a period of extreme price instability, in both directions, as central banks lose control.

This is exactly what the economist Hyman Minsky predicted in his financial instability hypothesis.** He postulated that a world with a large financial sector and an excessive emphasis on the production of investment goods creates instability both in terms of output and prices.
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Our present situation can give rise to two scenarios - or some combination of the two. The first is that central banks start exiting at some point in 2010, triggering another fall in the prices of risky assets. In the UK, for example, any return to a normal monetary policy will almost inevitably imply another fall in the housing market, which is currently propped up by ultra-cheap mortgages.

Alternatively, central banks might prioritise financial stability over price stability and keep the monetary floodgates open for as long as possible. This, I believe, would cause the mother of all financial market crises - a bond market crash - to be followed by depression and deflation.