Yeah, his error is funny. The stupid prescriptions it leads to are not funny.
As funny as rent seeking?
Michael Hudson on the American School of Political Economy
"The past few years, Dr. Michael Hudson has provided a number of articles and interviews which comprise important parts of this story.
"He has explained how the economics profession protects the vested interests of rentier and finance capitalism by completely ignoring the concept of economic rent seeking behavior
(i.e., pretending that all income is fairly earned, rather than recognizing that some income, such as from usury or speculation, is actually unearned and often quite harmful to the economy) here, and
here."