Yet very little, in the end, is completely new here. The specific concepts discussed in Going to Extremes—group polarization, informational cascades, rhetorical advantage—will be familiar to followers of Sunstein’s previous writings. Even the original research he cites (his Colorado experiment in particular) has been presented before. Nobody who has followed the author’s previous work on social theory and behavioral psychology will be surprised by his latest production.

But as is often the case among writers of Sunstein’s league, explanatory synthesis, and the elegance of a thesis proved, offer their own kind of value. What Going to Extremes lacks in terms of a broad, spectacular narrative, it makes up for in quiet comprehensiveness.

It helps that Sunstein’s prose is so lucid (which is not to be understood, in this case, as a polite euphemism for “mind-numbingly dull”). He writes with the measured cadence of a social scientist, in crisp sentences that go out of their way to explain themselves. And yet, underscoring Going to Extremes, and bubbling just below all the disciplined coherence, one senses an almost childlike fascination with the world and its workings, which both livens the book’s language and renders its arguments, if not more intellectually compelling, then at least more vividly charismatic than they would be were they articulated in the uniform vocabulary of social science. Occasionally an exclamation mark, like a rogue stowaway from Sunstein’s limbic brain, will make its way into an argument. (“Here is an especially disturbing finding. When people’s false beliefs are corrected, they might even become firmer in those beliefs!”) While some might call the scamp punctuation’s inclusion in the final manuscript a pander to the “pop,” I call it delightful.

Where Going to Extremes really shines, however, is in its other rare breakthrough moments: when it abandons explanation for exploration—when Sunstein uses his aggregated findings to take us somewhere new. And nowhere is this more true than in the book’s discussion of journalism. The tension that Sunstein establishes between the individual and the collective, between the peril and promise of group behavior, reflects an analogous strain in contemporary journalism: the informational desires of the individual versus the informational needs of a democratic citizenry.

The Web, for all the journalistic opportunities it offers, also enables the tyranny of the niche (Sunstein’s term is “cyberbalkanization”). The splintering of civic interest is quickly positioning itself as the bête-noire of digital-age democracy. It’s not only that the highly customized versions of journalism that are currently guiding the trajectory of innovation (RSS feeds! The Daily Me! mine magazine!) cede too much of the collective interest to the individual. They also deprive us of the simple serendipity of new information. And access to new information, Sunstein reminds us, is key—not merely to democracy, but to group dynamics more generally. “The most important reason for group polarization, and a key to extremism in all its forms, is new information,” he insists. “Group polarization often occurs because people are telling one another what they know, and what they know is skewed in a predictable direction. When they listen to each other, they move.”

The next question is how they move. If individual assumptions are predictors of extremism, as the author argues, then new information is the variable that can make the difference between, broadly, good forms of extremism (the civil rights movement, the American Revolution) and bad. As the behavioral psychologist Philip Zimbardo concluded about his own infamous prison experiment, “The line between Good and Evil, once thought to be impermeable, proved instead to be quite permeable.”

Its title notwithstanding, Going to Extremes is a study in moderation. While the book’s overarching subject is zealotry, and its narrative tension comes courtesy of polarization, Sunstein’s broad destination is the middle ground. Thus his ultimate breakaway moment, in which he ventures from description to prescription: what journalism now needs, he says, is an “architecture of serendipity.” Sunstein calls for a journalistic infrastructure that consciously re-imagines the front page of the dead-tree newspaper, ensuring that citizens will be exposed to the new information that they might not otherwise encounter.

If news organizations and journalistic innovators can overcome paradox to systematize serendipity, they will have a moderating influence, writes Sunstein. “Indeed, the architecture of serendipity is part of a well-functioning system of checks and balances; it helps to check the effects of echo chambers and ensure that those with blinders, or those who prefer information cocoons, occasionally see elsewhere. What they see may change their minds, even their lives.”

The regulator has spoken. The question that remains—and it is one that even the Kevin Bacon of Legal Academia might have trouble answering—is whether the moderate, middle-ground brands of journalism can shout loudly enough to stifle the bellowing of the echo chamber.

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Megan Garber is an assistant editor at the Nieman Journalism Lab at Harvard University. She was formerly a CJR staff writer.