I had a prof who was a Keynesian know nothing and preached a theory called the "Phillips Curve" during the Carter years to explain why both inflation and unemployment would increase simultaneously and indefinitely.
The only solution was for us to accept a lower standard of living. If that sounds familiar, just google Carter's "Malaise" speech.
Not long after Reagan came to office, the Phillips Curve theory, as it was originally preached, mysteriously dropped into a "memory hole."
I’m a believer in “biflation”. You can’t get anything positive out of keynesian monetary manipulation because it breaks the second law of thermodynamics (that is, you are not adding any positive information to the system). But GDP= M*V, so you can EITHER get inflation through M or deflation through crashing V. So you get both, pushing on a balloon.