A variety of arguments have been used in response. A standard one, which is particularly resonant today, is that it is the job of the university to provide a forum for everyone to state their arguments, but not to pick sides--and indeed that for the university to stand for one thing would chill the speech of those who have a different point of view.
But I hear something else too–that there is no point in trying to affect the morals of college students, because it's too late. They are who they are by the time they are in college, and our job is to enrich them intellectually, not to shape them morally.
A few years ago I ran across a nice refutation of this argument, out of the economics literature of all places. Cornell Economics professor Robert Frank and colleagues studied the effect on undergraduates of taking a standard rational-choice introductory economics course, and showed that students tend to become less altruistic and more selfish. So apparently we can have an effect on students' character after all–in the wrong direction.
I understand that other studies have confirmed and elaborated these results. The New York Times has another contribution to the literature today--The Dismal Education, Yoram Bauman of the University of Washington. His studies seem to show that studying economics doesn't degrade the generosity of the people who were going to be economists anyway. But it does have that effect on the "innocents" who did not enter introductory economics understanding the benefits of rational self-interest. Bauman writes,
… taking economics classes did have a significant negative effect on later giving by students who did not become economics majors. One interpretation of these results is that students who were not economics majors suffered a “loss of innocence” after taking an economics class, presumably because of exposure to certain ideas (like the invisible hand) or certain people (like economics teachers).
In contrast, students who became economics majors did not suffer a loss of innocence. This may be because they lost their innocence in high school — other research suggests that pre-university exposure to economics reduces giving — or perhaps even because economics majors were “born guilty.”At Harvard, more students take the introductory economics course than any other (though introductory computer science is catching up!). Don't studies like this have some relevance to the way we think all those future businesspeople, lawyers, doctors, engineers, and legislators should be educated?