The New York Times has a good article this morning that covers the debate within conservatism over the concept of epistemic closure, which basically is the idea that many political conservatives see conservatism as having definitively answered and settled all of the major issues of the day, from global warming to national defense to health care, and therefore when it comes to the issues, mainstream conservative thought does not need to be questioned or reexamined, only defended. From the article:

Mr. Bartlett, who lost his job at the Heritage Foundation after accusing George W. Bush of betraying the Reagan legacy, said in an interview: “Every intellectual movement needs to constantly question itself; otherwise it becomes stale. But conservatives have sort of reached a position of intellectual closure. They don’t think there are any new ideas of particular interest to them. Their philosophy is fully formed. The only question is how best to implement conservative ideas in the political debate.”

This article resonated strongly with me, as there was once a period in my life where I was a Rush Limbaugh devotee and believed that Limbaugh did indeed have factual answers to every political question of the day; and later, in my post-mission period, I believed the same about the revealed Gospel: that if I did not have an answer to some Gospel-related question, it was because I had not found the right authoritative pronouncement or received a personal revelation on the subject. In both cases, I felt I had “epistemic closure” and I just needed to defend the answers I already had or the authorities who provided them.
In my case, life experiences have destroyed my capacity for embracing epistemic closure in both politics and much of what passes for the Gospel, and now, in both areas, find myself accepting Limbaugh’s most-loathed of labels: a centrist. In politics, that means I accept the idea that there are usually valid points and concerns being articulated on both sides of the aisle, and in the Gospel, it means there are a few core beliefs that I have absolute confidence in, and I no longer view the vast ocean of Church leaders’ doctrinal statements as authoritative unless those statements are weighed against a host of specific criteria.
In Richard Poll’s classic discussion of the Iron Rod and Liahona models for approaching the Gospel, he makes the contentious point that it is common for Iron Rod believers (those embracing epistemic closure) to transition to the Liahona approach (more skeptical, more comfortable with ambiguity) through life experiences, but not vice-versa. This point is contentious because it puts a lot of us Liahonas in the position of saying to the iron-rod folks, “I have already worn your glasses and so I understand why you like them, but they blind you to a lot of important things in your field of vision, so I can no longer believe that they represent reality in a useful way.” It is a condescending point of view that we hold, but it is the only one possible for those of us who have lived in the comfort of epistemic closure at either end of the political or gospel-belief spectrum at some point.
The inevitably condescending nature of the centrist point of view is what causes people to rage against us more than they rage against their ideological opponents on the other side of the spectrum. Consider this political example from conservative site redstate.com:

What I am concerned about, however, is the extent to which those who fancy themselves conservative intellectuals – folks like Manzi, Frum, Douthat, Brooks, Sullivan and others – believe they are the second coming of Bill Buckley (hardly), but dismiss talk radio show hosts (and forums like RedState) as nothing more than blowhard hacks who pour out their own koolaid for the slobbering masses, too stupid to know the difference.
I have neither the desire and time nor the expertise to analyze in detail Manzi’s specific criticisms of Levin’s Liberty and Tyranny – most of which centered on the chapter on what Mark calls Enviro-Statism. What is striking about his burn-the-forest-down-to-find-the-tree approach is that it dismisses Mark’s book in entirety because he disagrees with some of the sourced (Mark’s book is well documented with numerous footnotes) material Mark provides in this one section in particular. And Manzi does so rather violently… accusing Mark of “epistemic closure.”
Now, I had to look that term up. Cuz I ain’t as smart as those guys who sit around in circles over at the New Republic, the New York Times, and increasingly, sadly on occasion, the National Review, and blather on endlessly about topics that would make even wonky professors’ eyes roll, much less a regular-old American like me who enjoys watching the DIY network and American Idol after getting back from the driving range and playing with my son.

This contempt for centrism (and critical thought in general, I would argue) is also found on in the left’s howls of “betrayal” by President Obama on a number of issues where he has chosen either pluralistic approaches or centrist positions.
In politics, people on the right and the left condemn adherents to Maoism and Khomeinism for their shared tendency to subordinate truth and accuracy to whether an idea “advances the revolution” or not, and yet that tendency is at the heart of the epistemic closure we see on both sides of the partisan aisle.
As for the Gospel’s application of this idea, if we have settled any Gospel questions at all in our hearts and minds, we are open to a valid accusation of epistemic closure. Having epistemic closure regarding a genuinely revealed principle is not a bad thing, but as the Iron Rod/Liahona discussion points out, the question of which of our Gospel teachings merit epistemic closure is an important debate in the age of blogging, where anyone can write a well-documented overview of “What Mormons Believe,” that would be wildly off the mark for 90% of members of the contemporary Church.