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On Tax Day in 2010, Andrew Boyd helped launch a campaign meant to raise awareness about economic inequality. In naming the movement, Boyd and his fellow activists wanted something that crystallized the lopsided-ness of the situation, and they settled on “The Other 98 Percent.” The campaign got some social-media traction as it began staging protests.

But its cultural reach paled in comparison to that of Occupy Wall Street, which came into being just a year and a half later. Occupy’s messaging—“We are the 99 percent”—is only one percentage point more extreme than that of Boyd’s movement, yet Occupy took off. Why? Since the movements didn’t differ much in their substance, was it something in 2011's cultural atmosphere?

Some people are now wondering the same thing about Thomas Piketty’s Capital in the Twenty-First Century, a book whose U.S. popularity this summer was so intense that no dependent-clause anecdote could capture it. While the success of Piketty’s book on some level is owed to the work’s inherent quality and rigor, three Nobel Prize winners have done extensive research on similar topics without stirring up the same craze.

To explore whether America in 2014 was prone to direct its attention to Capital, The Guardian editor Heidi Moore convened a roundtable of economists and financial thinkers—which even included one who has declined to read the book on the grounds that “the only field more self-confidently but just as regularly wrong as economics is nutrition.”

There wasn’t a consensus—nor a fully satisfying theory, which might be too much to ask for—but one agreed point was that Capital came along when there was an appetite for an argument making sense of economic disparities and increasingly plutocratic leadership. “My guess is that the book-buying upper-middle class of America today is greatly distressed when it looks at the world around it,” suggested economist and former deputy assistant secretary of the treasury Brad DeLong. The economists Stephanie Kelton and Tyler Cowen effectively agreed, pointing out that Capital confirmed a number of egalitarian assumptions already held by the bourgeois book-buying populace.

DeLong also speculated that Capital’s success was in part due to the fact that he was a foreigner who took a position not represented in mainstream American politics. Cowen, writing with Veronique de Rugy in the Times, explored a similar possibility back in April. In France, they noted, Piketty is considered an insider, having publicly worked with politicians as high up as the president, which might be one reason why Capital didn’t quite take off in France.

Matt Yglesias, writing in Vox, hinted at another theory explaining Capital's widespread uptake. Yglesias pointed out that the hardcover edition of Capital was more popular on Amazon than the ebook version, which implies that having—and displaying—a bound volume could provide utility beyond having read it. A fair number of stylized Instagram images back this theory up. (Pessimists might continue this line of thinking by trotting out an unscientific but still convincing analysis showing that only a sliver of Capital purchasers actually went through with reading it in full.)

In 2011, many liberal, upper-middle class people might have hesitated to join the Occupy movement because camping out in places like Zuccotti Park seemed too physically extreme. Before Capital came out, these people lacked a widely-recognized, physical way to show an allegiance to the fight against inequality, which could explain the book’s success.

Arriving at one unified theory to explain Piketty’s fame in 2014’s America would be reductive, but it’s the kind of exercise that might help illustrate the cultural conditions under which a social movement succeeds, or fails. The phrase “the 99 percent” may have caught on in 2011, but George Orwell actually deployed a slight variant of it in a letter dated June 3rd, 1940—it turned out the conditions wouldn’t be right for a movement to form around it until about 70 years later.


Relative Frequency of Google Searches for "Piketty" Over Time


If Google search frequency is any indication, it's fair to say that the fervor over the book has largely subsided (though, of course, there's still a good amount of residual interest). September isn't removed enough from the summer for a judgment anywhere near complete, but the next question is assessing Capital's long-term impact on the national conversation.

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