In 2012, conservative author Charles Murray wrote a book alleging that well-to-do liberals had walled themselves off from the rest of the country. Comfortably ensconced in their own bubbles, they couldn't understand the concerns and values of people who lived elsewhere.
Earlier this month, liberal students at Middlebury College proceeded to prove Murray right. Instead of listening to the speech he had come to deliver, they shouted him down. He was forced to retreat to another room, where his talk was video streamed. Afterward, someone assaulted the professor who was hosting Murray, pulling her to the ground by her hair.
The episode generated an eloquent apology by Middlebury president Laurie Patton and also a letter signed by dozens of faculty members, confirming their commitment to "free, reasoned, and civil speech" and to debate across ideological differences. "Only through the contest of clashing viewpoints do we have any hope of replacing mere opinion with knowledge," the letter declared.
That's a hugely important goal, and we should applaud the Middlebury faculty for affirming it. But we should also be skeptical about whether our elite colleges can achieve it on their own, given everything we know about them. The fancy colleges are liberal bubbles. The only way they can create real debate is to step outside of themselves.
I realized that after the election of Donald Trump, when my own campus held a series of community dialogues. There was only one problem: Everyone denounced Trump. The only disagreement was about what went wrong, not who was right. That's not a dialogue; it's a group therapy session.
In the privacy of my office, a few students confessed that they had voted for Trump. But they were afraid to say so in public, lest they suffer the animosity and ridicule of their peers. Like closeted gays, they had to pretend to be part of the same majority that despised them.
In that kind of environment, true and honest dialogue is simply impossible. So a group of us at Penn decided we needed to sponsor discussions with another college, where everyone didn't think like we did.
It wasn't hard to find one. Although right-wing pundits love to bash American colleges as bastions of left-wing political correctness, the PC problem is restricted to a handful of highly selective institutions. Most of the 4,000 post-secondary schools in the United States echo the broad spectrum of national opinion, not the die-hard liberalism of the elite colleges.
So it might surprise you to learn that the majority of American undergraduates describe themselves as "moderate," not liberal (or conservative). And when we look more closely, we find that they often don't fit our standard political categories at all. More than half of self-identified liberal students support capital punishment, for example, while nearly half of conservatives back gun control and abortion rights. And in 2011, several years before Trump proposed building a wall along the Mexican border, 42 percent of American college students favored a fence or wall to control illegal immigration.
That's not a sentiment you'll hear openly voiced at Penn, of course. The only way we could discuss it - or anything else involving Trump, really - was by partnering with another institution. So we reached out to Cairn University, which kindly agreed to co-sponsor two public forums with our students last month.
And what did our students learn? First of all, don't stereotype other voters. Cairn (formerly Philadelphia Bible College) is an evangelical institution, and most evangelicals in the United States cast their ballots for Trump. But not everyone at Cairn did. Some of their students condemned Trump as vehemently as the Penn crowd did, expressing outrage at his misogynistic behavior and also at his immigration order.
Second, the Cairn students who voted for Trump often did so holding their noses; just like many supporters of Hillary Clinton, they regarded their candidate as the lesser of two evils. "The forum helped me understand how conflicted we all are about the choices we have as citizens," one Penn student wrote, in a post-forum survey, "and how we are each challenged and disappointed in having to select elected officials who align with our faith/ethics."
Most of all, though, the Penn students discovered that people who disagreed with them were flesh-and-blood human beings. And once you have actually held a conversation with one - instead of simply flaring at them online - it becomes much harder to reduce them to caricatures. "I learned that it really was more difficult to hate or dismiss opponents when you are having a face-to-face discussion," another Penn student wrote.
That was one of the themes in a remarkable farewell address by Barack Obama in January. "If you're tired of arguing with strangers on the Internet, try talking with one of them in real life," Obama urged.
For our elite colleges, especially, that's become the most urgent task of all. And the best way to accomplish it is to pair up with less selective schools, which don't always see the world the way we do. The alternative is to stay trapped in our liberal bubbles, which limit how much we can learn.
Jonathan Zimmerman teaches education and history at the University of Pennsylvania, and is the author of "Campus Politics: What Everyone Needs to Know" (Oxford University Press). firstname.lastname@example.org