Rather than attempt to explain what the mainly neoclassical economists are going on about, I want to step back and try to translate their debate into terms that would be understood by people who do not share the same assumptions. I am pretty sure that post-Keynesian economists have a lot to say about the topic as well, but once again, they tend to be discussing wonkish points that would elude an outsider.…
I have an engineering background, and engineering is largely the science of trade-offs. I have no strong objections to qualitative discussions, but I would argue that we need to at least know the sign of the exchange ratio between two variables in order to say that there is a trade-off between them.
Very simply, if we can have a policy that lowers both the unemployment rate and the inflation rate (or at least leaves inflation unchanged), we cannot pretend there is a meaningful "trade-off" between them.
And this is hardly theoretical: in the United States, we saw a near monotonic decrease in the unemployment rate after the Financial Crisis, yet the inflation rate has done absolutely nothing interesting....Bond Economics
Is There Really A Trade-Off Between Inflation And Unemployment?
Brian Romanchuk