Epistemic Closure

Just after I finished law school, I worked for a federal judge. He used one expression that I have grown very fond of: "I am educable." When I explained to him the parties' dispute on a particular issue, he would give me his initial take, but insert the caveat that he was "educable" on the topic. Sometimes the cases and other authority I brought up changed his mind, sometimes it didn't, but he was always willing to listen to and consider it. That quality, perhaps above all the others, makes him a fantastic judge.
Unfortunately, that trait is in alarmingly short supply in American politics these days. Although I believe that the right is far more guilty of this than the left, both sides of America's political debate seem to fall victim to the refusal to credit any source of information with which they do not already agree. The fancy word for this is epistemic closure (I had to google it the first time I saw it). Two relatively recent examples:
1) After the Don't Ask, Don't Tell Vote, John McCain explained at a press conference that he knew the military did not seek out homosexuals. He was confronted by a reporter with testimony from an actual service member whose e-mail was searched for evidence that he was gay. His response was "I don't care what you say, and I don't care what others say, I know[.]" Distressing that someone who called himself a "maverick" would be so certain that he knows everything worth knowing about something that he would reject any information that could contradict his beliefs.
2) Hugh Hewitt simply rejected polling data because he didn't agree with it. You can say that Jerry Brown is the wrong choice for California governor. You can say that he shouldn't win. You can say he would take California in the wrong direction. You can even say that that the polling numbers suggesting that he is going to win are missing something, but only if you can explain why the polls are incorrect. What you can't do is what he did: simply repeating ad nauseum that you "don't believe the polls."
To me, the refusal to entertain new or contradictory information makes people stupid. I read the list of political positions taken by United States Senatorial candidate Sharron Angle and shake my head that anyone could vote for someone with positions so extreme and perhaps dangerous. But then I look at the polls and results which indicate that (a) enough people have voted for her that she won the primary; and (b) she is favored to win the election. You can either accept those facts as true and ask yourself why they are true, or you can deny them. But you don't learn anything worth knowing by rejecting them. And at some point, you can't deny reality. If she wins, you can say that there was some form of voter fraud that "stole" the election, but unless there is evidence of it (which there is unlikely to be), at some point you have to face the reality of Senator Angle.
Talk radio and Fox News seem to be the bastions of epistemic closure. Not sure how we go about convincing people that they don't know everything, but in case you are wondering, the fairness doctrine is a terrible idea.