Critics of economics like to say that its abstract theories lack real-world pay-offs. There is a glaring counter-example: the global rise of central-bank independence in the past 25 years. In the 1970s it was normal for politicians to manipulate interest rates to boost their own popularity. That led to a plague of inflation. And so rich countries and many poorer ones shifted to a system in which politicians set a broad goal—steady prices—and left independent central bankers to realise it. In a single generation billions of people around the world have grown used to low and stable inflation and to the idea that the interest rates on their bank deposits and mortgages are under control.
The Economist