Most successful academic philosophers spend their entire professional lives operating in self-satisfied insularity, exclusively trafficking in opaque jargon in obscure journals on technical issues of approximately zero application to ordinary life.

Colin McGinn is a notable exception. He's also a high-profile victim of the destructive ideological witch hunts now conducted on American college campuses with distressing frequency. Reason recently Skyped with McGinn to get his side of the fall and to discuss his landmark philosophical arguments, which advance an epistemic modesty that should resonate with libertarians. As he puts it, "there's no shame in admitting there's a basic ignorance about our conception of the world."

Born into an English mining town, McGinn's 40-year career includes hundreds of essays and dozens of books specifically geared to a general audience, on topics ranging from Shakespeare to cinema to drug decriminalization.

It's disappointing how little interest the average philosophy department has in this kind of engagement with the broader culture. McGinn says most of his colleagues viewed his non-technical work with a "mix of disdain and envy." The pretense is that professors should be free to indulge in pure reason unpolluted by popular opinion or market demands. Yet so much of the writing produced by academic philosophers is saturated with opaque insidery jargon that's just meant to signal the author's membership in a exclusive intellectual club. "Most philosophical writing is simply unclear. And [the authors are] incapable of being clear."

Ironically, communicating with a broader audience imposes exactly the discipline of thought that's largely absent from academic papers. "You have to go back to the basics and express the basic ideas clearly. If you just write in jargon, you never have to confront the basic ideas and arguments. You just repeat the words that other people use."

At the same time, McGinn's contributions to technical philosophical debates have been substantial enough to secure him tenured posts at several major American universities. That's an exceedingly rare combination of academic accolades and pop-culture fluency.

In 2012, though, something sad happened. His career imploded amidst accusations of an improper relationship with a female graduate student. No one claimed their relationship was sexual. It appears to have been a complicated, power-imbalanced emotional thicket between a star professor and an admiring mentee that may have turned inappropriate without actually violating the university's code of conduct.

But never mind the facts. The academy's self-righteous outrage machine quickly kicked into gear and a bunch of McGinn's colleagues ganged up to denounce him as a sexist predator. The administration at his employer at the time, the University of Miami, urged him to leave before disciplinary hearings had even started. "I wasn't receiving due process. They started asking me to resign. They didn't give me any reason."

After a couple months under intense presure, he complied. "The cards were totally stacked against me because the rules allowed the university to do whatever it wanted." (For more details about McGinn's case, see this excellent investigation from Katie Roiphe in Slate, which describes the professional carnage as "a great deal of destruction for a strange amorphous amorous entanglement.")

That particular blind moral crusade is a symptom of a larger problem. Professors and administrators often "force more complex phenomena into very simplified narratives with stock characters," McGinn says. In his case, they fixated on a politically fashionable story—sexual harassment perpetrated by a powerful white male, equipped with the accent of the Great Colonizer, no less!—that ignores the nuances of an actual human relationship. "That's what ideology does. It's a set of nice simple categories so you can process much more complicated facts."

Within this regime of enforced ideological homogeneity, the expression of unpopular opinions on sacred subjects is considered a kind of mind-violence. "There's lip service to the idea of free speech, but it's only within a narrow band of opinion. You have to toe the line. You can't have an individual point of view on racism or sexism or things like that. Forget it."

How exactly does the moist meat of the brain generate the thinking, feeling, choosing "I" that's now reading this sentence? It's a baffling question. McGinn's major technical philosophical contributions are about this "mind-body problem."

He's skeptical we'll ever fully work out the connection. We should "think of ourselves as having an evolved brain and an evolved intelligence which has some inherent limits. The possible reason we're having such a problem [scientifically explaining consciousness] is because of these inherent limits on our understanding of the world."

This position, commonly called "mysterianism," is grounded in an epistemic modesty libertarians should recognize—and embrace.

The faculty of reason is wonderful. It brought us air conditioning and tapas and the smallpox vaccine. But seeing it as all-powerful is a "strangely egotistical view of humanity. Would we say the same about the other human species that co-existed with us several million years ago. Do you think Neanderthals could necessarily understand every truth about reality?"

McGinn shares my wholehearted enthusiasm for the secular rationalist project. But many of its advocates seem to have simply swapped out the stodgy dogmas of traditional religion for an arrogant scientific triumphalism that quarters no doubt about the power of the human mind. He provides a welcome reminder not to "confuse materialism with the idea that somehow everything in the end will be explained. Why make such an optimistic assumption?"

"The physical world itself is very mysterious. Nothing in evolution says that we should be able to use those brains to understand everything about reality. That's just faith. It would be astonishing if the human brain as it now exists could get to the bottom of every question about nature. That would be an absolute miracle."