Stock market bubbles have three other recurrent features. The first is the role of what is sometimes referred to as asymmetric information. Insiders - those concerned with the management of bubble companies - know much more than the outsiders, whom the insiders want to part from their money. Such asymmetries always exist in business, of course, but in a bubble the insiders exploit them fraudulently. The second theme is the role of crossborder capital flows. Bubbles are more likely to occur when capital flows freely from country to country. The seasoned speculator, based in a major financial centre, may lack the inside knowledge of the true insider. But he is much more likely to get his timing right - buying early and selling before the bubble bursts - than the naive first-time investor. In a bubble, in other words, not everyone is irrational; or, at least, some of the exuberant are less irrational than others. Finally, and most importantly, without easy credit creation a true bubble cannot occur. That is why so many bubbles have their origins in the sins of omission or
commission of central banks.
Nothing illustrates more clearly how hard human beings find it to learn from history than the repetitive history of stock market bubbles. Consider how readers of the magazine Business Week saw the world at two moments in time, separated by just twenty years. On 13 August 1979 , the front cover featured a crumpled share certificate in the shape of a crashed paper dart under the headline: The Death of Equities: How inflation is destroying the stock market'. Readers were left in no doubt about the magnitude of the crisis:
