The World (actually US mostly) economy is a story of 2 theories and 2 people only

Paul Krugman on beating the recession:

1. Milton Friedman, in particular, persuaded many economists that the
Federal Reserve could have stopped the Depression in its tracks simply
by providing banks with more liquidity, which would have prevented a
sharp fall in the money supply. Ben Bernanke, the Federal Reserve
chairman, famously apologized to Friedman on his institution’s behalf:
“You’re right. We did it. We’re very sorry. But thanks to you, we won’t
do it again.”

2. John Maynard Keynes, who argued that monetary policy is ineffective
under depression conditions and that fiscal policy – large-scale
deficit spending by the government – is needed to fight mass

Strange how 2 economists have influenced the entire US thinking on macro economics, but its true.