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"John Lanchester at the Bank of England argues that the financial whizz-kids thought they could control money, and the inherent risk associated with playing about with it:
"The people inside the system were confident they had developed new tools to manage risk - that they had magically engineered away any risk.
That is never true. Increased risk is just increased risk.
"The basic assumption was that the tide would not go out, and the thing that astonished the world of money and caused the credit crunch - in fact it was the credit crunch - was the fact that the tide went out everywhere simultaneously."