Editor's Note: This article originally appeared on Real Clear Markets on March 14, 2017.

The case of Murray v. Middlebury has generated plenty of interest, and for good reason. For those who missed it, Charles Murray, a distinguished if often controversial social scientist, was prevented from speaking at Middlebury College by repeated noisy disruptions to both a public and hastily-arranged private webcast. Things turned nasty when Murray went to leave and an angry mob confronted him. Murray was pushed and shoved. His interlocutor, liberal political science professor Allison Stanger, was grabbed by the hair, and later had to be put in a neck brace in hospital. Once she and Murray managed to get inside the car, protestors banged on the doors and jumped on the hood.

Much more can and is being said about these events, but no better testimonies can be found than those of Murray and Stanger themselves. As Frank Bruni put it in the New York Times, the students at this “liberal” college were in fact displaying “illiberalism…issuing repressive rules about what people should be able to say and hear”. Jonathan Haidt, the NYU social psychologist says the incident “was a modern-day auto-da-fé: the celebration of a religious rite by burning the blasphemer.”

All true, and important. But one overlooked irony of the events at Middlebury is how they perfectly proved some of the points that Murray made in his book, Coming Apart: The State of White America, 1960-2010, which he had been invited to discuss. The book documents the separation of a “new upper class”, raised in rich neighborhoods, immersed in liberal, cosmopolitan values, and educated at expensive, liberal universities. In other words, it profiles the students of Middlebury College.

Middlebury’s students are among the richest and most privileged in America. The average enrollee comes from a household making a quarter of a million dollars a year, according to recent research on universities and social mobility. As many students at Middlebury come from the top 1% of households (23%) as come from the bottom four quintiles (24%). The annual cost of attending is almost $64,000 a year.

The domination of elite institutions of higher education by the upper middle class is a big problem for social mobility, of course. It looks like it might be bad news for free speech, too.

The domination of elite institutions of higher education by the upper middle class is a big problem for social mobility, of course. It looks like it might be bad news for free speech, too.

We have crunched some numbers using data gathered by the non-partisan Foundation for Individual Rights in Education, and found that the schools where students have attempted disinvite speakers are substantially wealthier and more expensive than average. Since 2014, there have been attempts at some 90 colleges to disinvite speakers, mostly conservatives. The average enrollee at a college where students have attempted to restrict free speech comes from a family with an annual income $32,000 higher than that of the average student in America.

In the figure below, we plot every university in America based on the proportion of students from families with incomes in the top quintile (vertical axis) and from the bottom quintile (horizontal). Marked in red are the “disinvitation colleges” described above. The pattern is clear: the more economically exclusive the institution, the more likely the students have attempted to hinder free speech:

Of course, we don’t know which particular students were involved in the violent protests at Middlebury. Perhaps they were from the 2.7% of the college’s students who come from families in the bottom 20% of the income distribution. It seems unlikely. Rather, it seems likely that many of the students most offended by the likes of Charles Murray come from the wealthiest families and attend the most expensive universities in the country. After all, when Murray spoke at Saint Louis University, where the median income of students’ families is half Middlebury’s, he was received respectfully, with some silent, peaceful protests.

Every single one of these protesting students ought to be made to study Gerry Cohen’s brilliant book: If you’re an egalitarian, how come you’re so rich? Then they should read Coming Apart. Few recent books have diagnosed so incisively the cognitive and cultural stratification of modern American life. Many of these students will likely find that they are among the group Murray lambasts for segregating themselves away from the mainstream of society, clustering in the richest “Super Zips”, and attending colleges like Middlebury.

There is much to disagree with in Murray’s work. But his depiction of class separation is on the nose. In fact, I go even further than that he does in my own book, Dream Hoarders (for which, to be transparent, Murray has provided some advance praise). The upper middle class is separating dangerously from the rest of society. This is driven in part by unfair “opportunity hoarding” mechanisms, including regressive tax expenditures, corrupt internships, and unfair zoning laws. But perhaps the greatest symbol of upper middle class separation is the elite university itself. Colleges like Middlebury—buoyed by such practices as legacy preferences in admissions—not only reflect but reinforce the continued growth of inequality.

The quintessentially liberal commitment to free and open dialogue is indispensable for building mutual understanding and respect in a diverse society. Cultural separation fueled by economic inequality, however, undermines that dialogue and respect. The spectacle of rich, “progressive” protestors refusing to hear a lecture on the roots of their own privilege; well, it tells you how much work there is to do. The class gap in American today is economic, educational and residential. Perhaps most dangerous of all, it is cultural, too. Mutual distrust across class lines is one of the causes of our current toxic politics. Greater understanding, shared learning and self-reflection are all needed now more than ever. And you don’t learn anything by shouting others down.