Some brief observations:
- Simon Wren-Lewis is asked to define K. His answer: "It is normally K(t) = δ K(t - 1) + I(t)." In times past, Wren-Lewis has seemed like he genuinely was interested in what heterodox economists have to say. But, with that kind of answer, he really needs lots more study to get up to speed.
- Noah Smith tries to provide an overview of contemporary economics. Many groups of economists I pay attention to do not exist for Smith, and I doubt he knows much about even the recent history of his subject. What would he make of, for example, Philip Mirowski's Machine Dreams?
- Matthew Yglesias alerts his readers to the existence of the Cambridge Capital Controversy. For Yglesias, the central question is the origin of returns to capital and the validity of marginal productivity parables organized around the idea of relative scarcity. I think this is a good account, given how terse this is.