Studies have shown a dominance of liberal ideas in academia, especially in the humanities. This article by Prof. Thomas C. Reeves argues that the reason behind this dominance is envy. A line that sums it up:
The shady groves of academe have cachet as a home address, but the pay is lousy, the prestige is negligible, and the power is derisory.
I am not sure that I buy it, but I thought I would mention it.
Also interesting is this blog post by George Mason University’s Dan Klein, which talks about other potential factors. One theory:
Few conservatives are attracted to work in scholarly fields dominated by the left, just as few males want to be nurses in a traditionally female field. People tend to giggle when a man wants to become a nurse, they say, and conservatives tend to feel similar embarrassment in entering leftist academe.
A better theory, which Klein explains, is “groupthink mechanisms”:
This giggle theory underrates what leftist domination does to faculties. In the recent book The Politically Correct University: Problems, Scope and Reforms, Charlotta Stern and I discuss groupthink mechanisms. The majoritarian procedure of each department means that once a majority leans left, the department will tend toward leftist uniformity. The pyramidal structure of each discipline means that publication, awards, grants, recommendations will follow the pyramid’s apex, and if the apex goes left it tends to sweep leftists/neuters into job posts throughout the pyramid.