A Pulitzer-prize winning journalist, who is also a self-described progressive, is taking academia to task for its bias against those who are religious or conservative.

Nicholas Kristof, an opinion columnist for the New York Times, published an article over the weekend suggesting colleges and universities begin hiring academics with diverse opinions, rather than just diverse skin tones and sexual preferences.

"The stakes involve not just fairness to conservatives or evangelical Christians, not just whether progressives will be true to their own values, not just the benefits that come from diversity (and diversity of thought is arguably among the most important kinds), but also the quality of education itself," Kristof wrote. "When perspectives are unrepresented in discussions, when some kinds of thinkers aren't at the table, classrooms become echo chambers rather than sounding boards — and we all lose."

Kristof cited studies that showed between just 6 and 11 percent of humanities and between 7 and 9 percent of social science professors are Republicans. At the same time, one study found 18 percent of social scientists said they identified as Marxists, leading Kristof to conclude "it's easier to find a Marxist in some disciplines than a Republican." Other studies have shown that hiring administrators openly discriminate against Republican applicants.

Two black evangelical professors were quoted in the article. Sociologist George Yancey said he experienced "more problems as a black" outside of academia, but "more problems as a Christian" inside academia — "and it is not even close."

Jonathan L. Walton, a professor of Christian Morals at Harvard University, likened the treatment of evangelicals to those of minorities. "The same arguments I hear people make about evangelicals sound so familiar to the ways people often describe folk of color, i.e. politically unsophisticated, lacking education, angry, bitter, emotional, poor," Walton said.

At least one professor is actively trying to fix the lack of intellectual diversity in academia. Jonathan Haidt, a social psychologist at New York University who identifies as a centrist, has started a website called Heterodox Academy to try and get schools to consider adding diverse opinions to their staffs.

Kristof doesn't go so far as suggesting a kind of affirmative action for conservative and religious thought, but does believe discussion is needed.

"Universities should be a hubbub of the full range of political perspectives from A to Z, not just from V to Z," he wrote. "So maybe we progressives could take a brief break from attacking the other side and more broadly incorporate values that we supposedly cherish — like diversity — in our own dominions."

Ashe Schow is a commentary writer for the Washington Examiner.