John Maynard Keynes, who never tried to conceal that he knew more than most people, also knew the limits to his knowledge. He wrote “about these matters – the prospect of a European war, the price of copper 20 years hence – there is no scientific basis on which to form any calculable probability whatever. We simply do not know.”
And Keynes was right. He published these observations in 1921, and 20 years later Britain was engaged in a desperate, and unpredictable, struggle with Germany.
But lesser men find prognostication easier. I have been looking at some of the models people use, in both the public and private sectors to predict events.