by definition

The NYT has an article exploring the reasons that professors seem to lean left. No one seems to want to look at traits of conservatives & liberals that lead them to that very label. Liberals have a tendency to want to help the less fortunate and often at great expense to themselves while conservatives are so pro market economy that its a race to make and keep the most money possible and everyone else is on their own. That perspective alone eliminates an academic profession.

http://www.nytimes.com/2010/01/18/arts/18liberal.html