Commencement was over, and we had awarded diplomas to the more than 800 graduates in a timely way. I had made remarks, as I always do, connecting the education they had received with events in the world at large, especially the combination of corruption and inertia in Washington. While marching across the stage, a few dozen graduates managed to express their disappointment that the administration in general and the president (me) in particular weren’t as progressive as they would like on issues such as sexual assault, divestment from fossil fuels and support for underrepresented groups.

The commencement address at Wesleyan University this year was given by the MacArthur grant-winning poet Claudia Rankine. As president and master of ceremonies, I admit I was focused on the way she engaged the students -- no easy task. The address was political, as antiracism speeches must be, and it was smart, funny and moving by turns. She concluded by expressing, “Love to each of you and love to your bad behavior in the boardroom, on juries, in the office, on the street, at your dinner tables in all and every space that believes it can hold racism, sexism, homophobia, anti-Muslim rhetoric and on and on. Love to you and your wild and unruly hearts imagining our world again.”

As families milled about after the ceremonies, taking pictures, sharing hugs and high fives, I was suddenly called out by an angry voice: “You annihilated my existence,” yelled a middle-aged man. Taken aback, I wasn’t sure I heard him right. “You annihilated my existence,” he repeated and went on to say that the ceremony had left him out and was an example of why people hate closed-minded universities today. Evidently, he did not feel included in the poet’s reference to unruly hearts.

I was surprised by this outburst, but perhaps I shouldn’t have been. I had recently encountered pushback from some on the other end of the political spectrum when I published an op-ed in The Wall Street Journal calling for an affirmative action program for conservative ideas on campuses. Noting the tilt to the left in many humanities and social-science divisions at selective colleges, I argued that it was not enough to take a free-market approach to intellectual diversity. Being unruly at a Northeastern university these days should include making a special effort to enhance the study of conservative (religious and libertarian) traditions, broadly conceived. We should avoid the hate-filled provocateurs of the alt-right and instead encourage the serious study of ideas outside the progressive consensus.

Many students and colleagues who think of themselves as being on the left, as I do, worked themselves into a position of outrage, even victimization, after hearing about my short essay. A young alumna returning to campus for her reunion told me that I had made it more difficult for people like her to get an education because I was claiming that this education should contain ideas contrary to her own. She didn’t say I had “annihilated her existence” but seemed to feel that way.

What’s going on?

Survey data released this week by the Pew Charitable Trusts have given me a better feel for the intensity of such reactions. It is clear that many national institutions with hitherto broad public support are now viewed very differently depending on one’s ideological position. Perhaps it is unsurprising that Republicans and right-leaning independents have a far more positive view of churches and a more negative view of labor unions than do Democrats and left-leaning independents. Although the media’s popularity among those tilting left has grown over the last year, that doesn’t offset the steep decline among Americans on the right who think the national media is having a positive impact on the country. Interestingly, one can’t find a majority who think favorably about banks and financial institutions, though Republicans are more positive (46 percent) than Democrats (only 33 percent positive).

The sharpest partisan divisions appear when people are asked whether colleges are “having a positive or negative impact on the way things are going in the country.” Fifty-eight percent of Republicans and their ideological friends now say that colleges are having a negative impact, while 72 percent of Democrats and their comrades see colleges as positive. This gap has widened significantly in recent years. In 2015, a majority of GOPers thought positively about higher education; in fact, the decline among those who lean to the right is close to 20 percent! The views of colleges of those who fall toward the left have been pretty stable.

Colleges and universities have long been the screens upon which groups project their own fears and anxieties. Older people wonder what the next generation is coming to, or worry that their children are having their lives distorted by a professoriate not part of their “real world.” In the past two years, the fantasy of political correctness on college campuses has been a catch-all for a range of people angry about the world, especially those concerned about their status in our age of rapidly growing inequality. The PC campus bogeyman has an important function -- it pumps up the myth that our biggest problems stem from a lack of tolerance for ideas friendly to the status quo. When fraternity brothers are disturbed by university restrictions on how they organize parties, they find a new rallying cry in bemoaning “political correctness.” When middle-aged veterans of college protests of yesteryear no longer see their own battles and slogans repeated by today’s students, they complain about PC culture undermining free speech. When men, even elected officials, are caught bragging about sexual assault, they punch back at political correctness.

As I noted in the run-up to the presidential election, there just isn’t any downside to attacking this imaginary monster of groupthink, and so people friendly to the status quo will continue to trumpet their own courage in “not being PC” as they attack society’s most vulnerable groups. Racism and xenophobia get a free pass when folded into an attack on PC elitism.

At the same time, those attacked as PC shouldn’t take the bait and content themselves with labeling anyone who attacks them as racist. Those who point out the dangers of big government, emphasize the needs of national security in an age of terrorism, extol the virtues of family and religion, or defend free speech deserve intellectual engagement -- not insult and irony. Those who support a progressive campus culture make a big mistake if they think they are protecting that culture by insulating it from ideas that come from conservative, libertarian and religious traditions.

Demonizing people because they have ideas different from your own has always been a temptation, and lately it has become a national contagion. College campuses are not at all immune from it, but this malady is fatal for liberal education. Many people are so accustomed to curated information -- be it from social media feeds or just from one’s choice of cable news -- that they have lost the ability to respond thoughtfully to points of view different from their own. When they are confronted with disagreement, they may feel their “existence is annihilated” or that the person with whom they disagree wants “to make it harder for people like themselves to get on in the world.”

So those on the left and on the right surveyed by the Pew Foundation may actually share the same picture of colleges but just evaluate it differently. Democratish survey respondents may be imagining campuses as places where they would find people who hold views like their own, and Republicanish respondents may be thinking that people like them would simply be called nasty names were they to speak out there. Both groups may be imagining colleges in blue states and red states as places where like-minded people go to become more alike.

This is a disastrous view of colleges and universities, one that we who work on campuses must do our best to dispel. We must highlight and enhance the ways that students and faculty members consider alternative perspectives on culture and society; we must promote vigorous debate that doesn’t degenerate into personal attack. This kind of consideration and debate is increasingly rare in the public sphere, and that’s why it is more important than ever to cultivate the terrain for it on our campuses. By this I don’t mean inviting provocative entertainers to the campus so as to get free speech points at the cost of providing a platform for idiocy and abuse. I mean enhancing conditions for the serious study of alternative visions of justice, freedom, individual rights and communal responsibilities. I mean not just sharing biases with students in acts of solidarity, but testing one’s biases by engaging with ideas that also challenge the campus consensus.

Even when colleges and universities are seen as places to engage with ideas and inquiry that break a consensus rather than support it, when students and faculty are seen as capable of trying out ideas without fear of reprisal, not everyone will say that colleges are having “a positive effect on the way things are going in the country.” If we are doing our jobs, some should always object to what happens on campus. But when we are getting objections (and support) from people who hold a variety of perspectives, then we can be more confident that we are fostering the intellectual diversity essential for higher education’s role in this country.