Just reviewing what epistemic closure is…a good 2010 NYTimes article: “‘Epistemic Closure’? Those Are Fighting Words”
It’s a very good read.
Reading a logical analysis of ‘epistemic closure’ — the logic topic — on http://plato.stanford.edu, there is an argument against the existence of epistemic closure: 𝘛𝘩𝘦 𝘈𝘳𝘨𝘶𝘮𝘦𝘯𝘵 f𝘳𝘰𝘮 𝘵𝘩𝘦 𝘈𝘯𝘢𝘭𝘺𝘴𝘪𝘴 𝘰𝘧 𝘒𝘯𝘰𝘸𝘭𝘦𝘥𝘨𝘦.
I think we MUST concede that there is a logical definition, and then there’s its non-logical application. It’s precisely 𝘣𝘦𝘤𝘢𝘶𝘴𝘦 there is lack of analysis of knowledge that there is closure.
Or better still, you can “analyze” what you 𝘵𝘩𝘪𝘯𝘬 is knowledge (when it’s not knowledge) and simply reinforce “truth” of what you believe (bias confirmation) or just add volume to the muck of what you believe is fact.
What we mean by closure is that new knowledge based on analysis of facts (existing “knowledge”?) or even the willingness to consider facts outside your echo chamber is non-existent or seriously (willfully) inhibited.
With epistemic closure, when there is cognitive dissonance, people “resolve” the dissonance in favor of what fits the narrative they want to believe or that fits within what they think they “know.”
The existence of “death panels” was a shining example. Without critical evaluation of facts (like actually reading the bill), you hear “death panels” from a demagogue; and no amount of presenting facts works to dissuade you from believing such a thing exists. It echoes well with both what you want to believe and what you think it fits “logically” into what you think you “know.”