Pour Greg Mankiw, Professeur à Harvard:
"Point 1 [the history of inequality and wealth.] is a significant contribution. "
"Point 2 [the forecast of how things will evolve over the next century] is highly conjectural. Economists are really bad at such things. In particular, the leap from r>g to the conclusion of a growing role of inheritance in society seems too large to me. Many capital owners consume much of the return on their capital, so wealth does not grow at rate r. (...) In addition, wealth per family shrinks as it is split among children. (...) [NB: r est la rentabilité de l'épargne et g est le taux de croissance économique]
"Point 3 [policy recommendations] is as much about Piketty’s personal political philosophy as it is about his economics. As we all know, you can’t get “ought” from “is.” (...) No amount of economic history will tell you that John Rawls (and Thomas Piketty) offers a better political philosophy than Robert Nozick (and Milton Friedman)."
Source : http://gregmankiw.blogspot.ca/2014/04/first-thoughts-on-piketty.html
Le face-à-face Mankiw vs Piketty : http://onpoint.wbur.org/2014/04/29/piketty-mankiw-inequality-america-middle-class
Un bon résumé critique du livre par Larry Summers, Professeur à Harvard, ancien Président d'Harvard, ancien économiste en chef de la Banque Mondiale, et ancien secrétaire au Trésor américain : http://www.democracyjournal.org/32/the-inequality-puzzle.php?page=all