Some liberals, of course, attribute this to their own immeasurably greater moral and intellectual superiority.

One theory for the scarcity of Republican professors is that conservatives are simply not that interested in academic careers. A Democrat on the Berkeley faculty, George P. Lakoff, who teaches linguistics and is the author of "Moral Politics: How Liberals and Conservatives Think," said that liberals choose academic fields that fit their world views. "Unlike conservatives," he said, "they believe in working for the public good and social justice, as well as knowledge and art for their own sake, which are what the humanities and social sciences are about."

The thought that acadmics are self-selected for the conditions found in academia must somehow be discredited by conservatives, as illustrated by your one-line intro to the quote.

Face it, Tom. I said this before here, a long time ago: people who choose the academic world are not usually in it for the money. Conservatives tend to believe, as illustrated by you and others here, that economic independence is paramount. So they go after the jobs that make the money. No level of teaching answers that description, except maybe for Phil's neighbors who teach at Ivy League universities, and athletic directors almost everywhere.

Now, as to why liberals would choose to go into jobs without the money, that's up to liberals to define. It certainly isn't the money, so it must be something else. If it's a thirst for learning or love of art for its own sake, if it's a desire to serve society or an urge to contribute to justice in the world, why should conservatives feel obliged to undermine that? Is it because it offends their own sense that they have superior virtue? Does it threaten their self-defined identity as the Good and the True, that their opponents might have noble reasons to take the path they have? Or is it merely that the object is not merely to win, but to completely discredit and obliterate the opposition?