A better response is for critics to stick with the rate of profit versus growth argument while dumping the neoclassical marginal productivity aspect of Piketty’s theoretical argument. Mainstream economists will assert the conventional story about the profit rate being technologically determined. However, as Piketty occasionally hints, in reality the profit rate is politically and socially determined by factors influencing the distribution of economic and political power. Growth is also influenced by policy and institutional choices. That is the place to push the argument, which is what critics of mainstream economics have been doing (unsuccessfully) for decades. The deep contribution of Piketty’s book is it creates a fresh opportunity in this direction.
From Yglesias interview:
Picketty:
It's not only in US. It's economists everywhere. I think what they're doing wrong is that in order to distinguish themselves from other disciplines, in order to look like we all are scientists, they use too much complicated math just for the sake of it.
Math is fine. Math is very cool. But very often, they tend to push for more sophisticated math just to push off other people. It's an easy way to have the appearance of scientificity. For a real mathematician or physicist, the math will not be terribly impressive but it's enough to impress those economics departments that are less good at math and those social scientists who are less good at math.
I think math is useful, if you have a good ratio of facts to theory. But most of the time the economists do the opposite. There are incredibly sophisticated mathematical models with a very tiny empirical component.
For the most part it's like [Pierre] Bourdieu, "La Distinction," with art taste. It's a way to distinguish your self from the commoners and to look more sophisticated.
