It’s hard to think of a work of economics—certainly not one published in the past 30 years—that has had as extraordinary an impact outside the guild of professional economists as Piketty’s Capital in the Twenty-First Century. Its thesis is that capitalist economies have a natural tendency to incubate highly unequal distributions of income and wealth.
The book struck a nerve, but has also met with strong criticism. The Financial Times accused Piketty of serious statistical errors that undermined his conclusions. (Piketty responded at length to the FT, saying he did not find its rather technical objections “particularly constructive,” though he did allow that his historical data series could and should be improved upon in the future.) Other commentators have found his definition of capital problematic in concentrating on physical assets rather than household wealth and his somewhat utopian recommendations for a global wealth tax unconvincing.