Affirmative action is about diversity. But campuses won’t allow diverse opinions about it.

A few years ago, during a visit to my office, a student in one of my courses told me he opposed the use of race in college admissions. When I asked him why he hadn’t shared that view in class, he grimaced.

“Everyone would think I’m a racist,” he said. “I can’t take that risk.”

He’s right. And that points to a huge contradiction in our universities’ approach to affirmative action: We support the practice as a way to enhance the diversity of the student body, but we suppress diverse opinions about affirmative action itself.

That can’t be good for the university or even for affirmative action, which could only benefit from a full-throated debate.

That debate reached a fever pitch last month, when the Supreme Court heard arguments in two lawsuits challenging the constitutionality of affirmative action. Most adults — including most Black and brown adults — do not think race and ethnicity should be considered in admissions, as the Pew Research Center reported earlier this year. However, there are blocs of citizens who strongly favor the practice. News flash: Voters disagree about affirmative action.

News flash: Voters disagree about affirmative action.

That includes university students. A BestColleges survey this fall showed that students were split almost evenly on affirmative action: 37% favored it, while 35% did not.

But you wouldn’t know that walking around campus. As my own student correctly surmised, our universities have placed affirmative action outside of permissible discussion. If you oppose it, the assumption goes, you must be a very bad person. And you’ll keep quiet, if you know what’s good for you.

To many people, the purpose of affirmative action is to help colleges level the playing field for students of color, who remain at a disadvantage in the admissions process. But when the Supreme Court weighed in on the practice in its landmark 1978 decision, the court said the rationale for affirmative action should be pedagogical. Namely, the court determined that admitting a diverse array of students would help schools promote “a robust exchange of ideas.”

I believe in that ideal, as deeply as I believe in anything else. But I don’t believe our universities are adhering to it, especially when it comes to affirmative action itself.

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If we took the charge of “a robust exchange of ideas” seriously, our universities would urge people who oppose affirmative action to come out of the woodwork. In the buildup to the Supreme Court arguments, many schools released statements or submitted briefs in support of affirmative action. But no major institution called for a robust exchange of ideas about it.

We talk a good game about “difficult conversations,” “dialogue across difference,” and so on. But there’s nothing difficult about a conversation where everyone agrees with each other.

Defending affirmative action at the Supreme Court last month, a lawyer on behalf of the University of North Carolina argued that admitting people from diverse backgrounds “reduces groupthink” on campus. Yet our universities have actually fostered groupthink about affirmative action and a host of other topics. Even as we have diversified our student population, we have become less friendly to diverse points of view.

And if you think otherwise, have a look at a 2020 student survey conducted by three professors at, yes, the University of North Carolina. Over two-thirds of conservatives, roughly half of moderates, and about a quarter of liberals reported self-censoring in class because they feared “social sanction, or even outright grading penalties, for sharing their views,” as the professors wrote. Most alarmingly, nearly a quarter of conservative students said they worried that peers would file a formal complaint against them — yes, you read that right — if they expressed an unpopular opinion.

Let me be clear: There aren’t club-wielding goons in sunglasses walking around our universities, enforcing the campus orthodoxy on affirmative action. Instead, we do it to ourselves. But that means we can undo it, too.

That would require us to acknowledge that equally decent and informed human beings disagree about the subject. We would admit that none of us knows everything about it. And, most of all, we would declare — in the spirit of “a robust exchange of ideas” — that the only way to learn more about affirmative action is via open and honest discussion. The real question is whether we have the courage to do that.

Jonathan Zimmerman teaches education and history at the University of Pennsylvania. He is the author of “Whose America? Culture Wars in the Public Schools,” which was published in a revised 20th-anniversary edition this fall by the University of Chicago Press.