A Martian economist visits earth. Not only does its arrival prove – as many suspected – that some economists really do live on other planets, it also provides fresh perspectives on our world.

Earthling economists chatter excitedly to our visitor about the stunning growth rates in China. This miracle economy of the 21st century has overtaken France and the UK to become the world’s fourth biggest. Europe is the past; the US is the present; and China is the future, they proclaim. The centre of economic gravity in the world has shifted decisively towards north-east Asia.