An economics professor recently warned of the harmful consequences caused by academia’s increasingly leftist tilt.

Phil Magness, who teaches at Berry College in Georgia, recently published an article in Areo Magazine detailing some of the explanations for academia’s shift to the political left over the last two decades.

"When minority viewpoints are made to feel unwelcome on campus, open inquiry dies off and entire areas of study become echo chambers."

While the percentage of self-identified liberals in academia had remained fairly consistent for nearly 30 years, at between 40 and 45 percent, Magness notes that the Higher Education Research Institute’s annual survey shows that the numbers began rising in the mid-1990s, reaching 60 percent in the most recent survey conducted in 2013.

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After reviewing research from the American Academy of Arts and Sciences, which tracked academic hiring in the last decade, Magness discovered that one possible explanation is that more professors are being hired in traditionally left-leaning fields.

The data show that the fastest-growing fields over the last decade have been “fine arts (1.82 percentage points), humanities (1.01), and social sciences (0.83),” whereas less politically-charged fields, such as the natural sciences and engineering, have actually lost faculty members during the same period.

“What this basically means is that the most politically skewed disciplines—the humanities, fine arts, and social sciences—have grown their faculty at a faster rate than other less politicized disciplines,” Magness explains.

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The increasing skew to the left is worrisome because it can breed an intellectual environment hostile to students with minority viewpoints, Magness told Campus Reform.

Indeed, a recent survey conducted by Heterodox Academy, a group dedicated to promoting viewpoint diversity in academia, found that many conservative students consciously avoid sharing their opinions in class because they fear retaliation.

Additionally, Magness argues that graduate students are especially impacted, asserting that political bias becomes more pronounced in the higher echelons of academia.

“If you want to study English, where 80% of faculty now self-identify on the left, but you know that your views are going to be unwelcome in almost any English graduate program in the country, choosing an alternative—and less politicized—area of study will start to look like a safer career option,” he points out.

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Not only can this leftward skew discourage students from studying the subjects they most enjoy, but Magness warns that the problem will likely get worse in the future.

“The resulting self-selection effects only worsen the political imbalance, because almost all new PhD students will now come from the dominant viewpoint in that discipline,” he explained, adding that as these new PhDs become professors themselves, “the discipline as a whole skews even further in the direction of ideological uniformity.”

To mediate this, Magness hopes that colleges will embrace a stronger commitment to academic freedom and viewpoint diversity.

“When minority viewpoints are made to feel unwelcome on campus, open inquiry dies off and entire areas of study become echo chambers,” he told Campus Reform.

Follow the author of this article on Twitter: @Toni_Airaksinen