Learning the lessons of history

Asked in 1949 about the importance of the French Revolution of 1789, the Chinese communist leader Chou-en-Lai thought for a bit, stroked his straggly beard and replied: "It is too soon to say." In these testing times for stock markets worldwide, a similar sense of perspective is essential. The world's leading indices are, to use highly technical language, down. The technology-rich US Nasdaq index has lost around 40% of its value since its all-time high on 10 March this year. The UK's techmark index has done much the same thing. On continued worries about earnings, the Middle East, this w...