Over the weekend, New York Times columnist Nick Kristof devoted his attention to “a liberal blind spot” in higher education: While colleges seek to fill their lecture halls with professors across the spectrum of race and gender, the self-avowed liberal noticed the ivory tower discriminates against conservative Christians. “Universities are the bedrock of progressive values,” Kristof wrote, “but the one kind of diversity that universities disregard is ideological and religious. We’re fine with people who don’t look like us, as long as they think like us.”

The numbers are staggering. In the studies of social sciences, about 7-9% of American professors say they are Republican but 18% say they are Marxist, wrote Kristof. In other words, you have a better chance learning under someone who follows the political philosophy responsible for the deaths of hundreds of millions of people than one of the two primary political parties in America today. Often, conservative professors try to hide their beliefs — at least until they can make tenure.

Of course, this means conservative and Christian ideas are marginalized in the place where people go to supposedly experience a cornucopia of thought. It’s not just professors, either. Think back to the numerous conservative speakers disinvited from speaking at campus events because they held “incorrect” beliefs. Most recently, this almost happened to Wall Street Journal columnist Jason Riley. Last week, Virginia Tech apologized after Riley wrote how he was disinvited from the campus because his views on race might spark student protests. The school claims it was all a misunderstanding. Right.

The absence of free thought can be disastrous. When the ultra-liberal thinking takes hold and there’s no way to keep it grounded through rigorous debate, then the college floats off to la-la land. Harvard University announced it was going to prosecute any student it found to be a member of a male- or female-only club starting in 2017. Why? Administrators want to combat the bogeyman of sexual assault, and joining a frat also smacks of privilege and exclusion. In other words, students have the freedom to think whatever they want and associate with whomever they want — as long as the university agrees.

> Correction: It was Virginia Tech, not the University of Virginia, that apologized to Riley. It has been corrected and we regret the error.