Could you clarify the argument? Near as I can tell, he merely claims taxing the rich will benefit the economy, and provides no justification for this claim beyond vague allusions to the idea that it happened after WW2. I can't figure out what mechanism he is arguing.

He also argues against straw-men such as this: Proponents of trickle-downism will argue that the little-taxed corporate executive will in fact share his wealth by spending it

(Proponents of "trickle-downism" don't claim this.)

and uses misleading definitions like this: A poor person, by contrast, needs more than he can afford.

(By this definition there are virtually no poor people in America, thus his policy prescriptions are impossible. http://www.census.gov/prod/2008pubs/h150-07.pdf )