"Lord Keynes" concludes with:
The leading proponents of MMT hold that it is now an independent macroeconomic theory (by contrast, the Cambridge Post Keynesian Mark Hayes regards MMT as a sub-branch of Post Keynesianism). At the very least, Post Keynesianism can be regarded as the important macro-theory that stands behind MMT as one of its intellectual fathers, so to speak.
Perhaps it is even possible to think of MMT economists as a new generation of Post Keynesians - that is, as a younger generation that has developed Post Keynesian theory in new ways.Read it at Social Democracy For The 21St Century: A Post Keynesian Perspective
The History of Modern Monetary Theory
by Lord Keynes