"There were many Moliére characters speaking Keynesian prose in the depression years before 1936. What Keynes’s General Theory gave us, which Ohlin’s inspired journalisms could not at all offer, was a new manageable paradigm that we could explicitly express — and test, and criticize, and improve, ... , and be bewitched by. Long before Kuhn, Schumpeter used to insist that old theories are not killed by simple facts: It takes a new theory to kill an old one. The mind cannot operate in terms of a melange of sensations. It needs a road map to perceive patterns of regularity and persistence."
Paul Samuelson

January 1, 1970