Despite what the majority of academic Macroeconomics textbooks say.....
WTG YellenIdiot.
Actually it’s the Macro textbooks that are the problem. It’s been that way for decades. I was lucky that I had an Austrian Econ prof for two macro classes in college. He despised John Maynard Keynes. My prof was brutally difficult. The math just rolled off his finger tips. He would start on one board and wrap around the classroom without pausing. He didn’t care, it was our job to keep up with him. I loved learning from people like that.