This spring, approximately 3.5 million students across the United States will receive their diplomas from institutions of higher education. Most will listen to commencement speakers who offer wisdom, perspective, and encouragement before they venture out into the world. It would serve students better to have speakers that challenge, instead of confirm, their pre-existing ideas and perspectives.

Two of the headliners this year are President Trump and Mark Zuckerberg. Trump will be at Liberty University, while the 32-year-old Facebook founder and CEO will address the graduating class of Harvard. There is, of course, nothing surprising about either of these choices — that's the problem.

One could say the Republican president will be "preaching to the choir" in more ways than one. Liberty is the largest evangelical Christian university in the world, situated in the deep Republican foothills of Appalachia, and led by Jerry Falwell Jr., a prominent Trump supporter.

Bu Zuckerberg, too, will also be preaching to a choir, albeit a more secular one. Harvard is what most see as the ideal of an elite university, entrenched in the markedly "blue" metropolis of Boston.

Harvard's employees, for instance, gave $473,414 to Secretary Hillary Clinton in 2016, compared to only $7,662 for Trump. A group of Harvard graduate students recently started a "resistance school" to oppose the president.

The all-too-predictable roles that will be played by Trump at Liberty and Zuckerberg at Harvard – to say nothing of the words they will likely offer – is tragically demonstrative of the lack of viewpoint diversity that risks limiting American academia to specific perspectives. There is nothing Trump will say to Liberty University students or Zuckerberg to Harvard that the students haven't heard before on campus, nothing that will offer a different social or political perspective, or challenge their worldview.

For most of America's storied history, our colleges and universities offered an education that cherished and encouraged dissent and skepticism.

Today, according to a recent study, a majority of all university professors — especially within the social sciences — lean left. Yet, it's conceivable that an overwhelming majority of our country's undergraduates may go years without encountering a single conservative author, book, or idea.

In short, most students, from their first class to commencement, will have little exposure or experience outside of progressive thought. As of this writing, only one of America's top twenty universities had booked a right-leaning speaker: Vice President Mike Pence. And though he will be addressing the graduating class at the historically-traditional Notre Dame, there will likely still be resistance.

Most worrisome, the apparent inability of students to listen to (or academically refute) provocative, unsavory and offensive viewpoints has led to violent incidents, such as a coordinated protest at the University of California, Berkeley against the provocateur Milo Yiannopoulos causing $100,000 in damages, or the violence at Middlebury College in response to Charles Murray, which put one professor in the hospital.

If we want our young people to emerge and engage in a world and a nation where we treasure the free exchange of views, opinions, and ideas, then this state of affairs must be changed.

The solution is a simple one: viewpoint diversity. We seek out and champion diversity in every other form. Why not intellectual diversity that represents a wide spectrum of political ideologies?

With access to a nearly-infinite range of information, it's easy to isolate and surround oneself with content that endorses our politics. Our social networks, media choices and reading habits are segmented and sophisticated algorithms deliberately filter out dissenting news to ensure we reside in echo chambers. That's even more reason the campus must return to being a forum for debate that pushes the bounds of staid wisdom.

It's estimated that by 2020 two-thirds of American job opportunities will require some form of higher education. If students continue to be coddled and shielded from offense and the unfamiliar, they will be completely unprepared for survival, let alone success, in a world that is colorful, strange, and frequently messy.

Yet, despite the polarization, there are encouraging signs that the pendulum is swinging back the other way. Petitions in support of free speech are circulating on campus to maintain environments of academic rigor and reasoned debate. Membership in my organization, the Heterodox Academy, has steadily grown to almost 700 members, and media have begun covering the organization widely. The organization aims to advocate for more intellectual diversity in higher education.

The introduction of viewpoint diversity to campus does not require faculty members and students to accept ideas and beliefs different than their own. But it does mean respecting the fact that others might have competing ideas and beliefs. This understanding is what we need to build on, instead of the idea that the other side is to blame for all current ills.

If we seriously want to start healing our country's deep divisions, we might consider looking first at addressing the institutions training our country's future leaders. If students aren't trained to deal with opposition, then we'll all soon be to blame for the loss of our democracy.

Simply switching commencement speakers is a start of a long road we all will travel together — hopefully walking side by side.

Jeremy Willinger is communications director at Heterodox Academy.

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