Just for grins, here's a video by "patcondell" that I think makes a positive contribution to understanding the "closed-minded anti-theist":
https://www.youtube.com/watch?v=M114bK4qaiM
The point of interest to be drawn from his perspective on this topic is this: if you're trying to equate the dogmatic, ears-plugged theist to the dogmatic, ears-plugged anti-theist, there is still a qualitative difference between the two that cannot be ignored. Theistic pig-headedness is founded on myths having no evidential basis and no chance whatsoever of objective confirmation, whereas anti-theistic pig-headedness is based on rejecting mythology in favor of assertions that at least offer some chance of being verifiable or falsifiable.
As a result, when faced with actual evidence that would contradict a given belief, the theist is more likely to deny, ignore or misrepresent the evidence in order to keep the belief and circumvent the cognitive dissonance. Meanwhile the anti-theist is more likely to adjust his belief (or at least his statement of it) to accommodate the evidence -- but it has to be "real" evidence, with the power of accurate prediction or solid entailment, to make this happen.
Of course, if you point to pig-headed anti-theists who also happen to be "9-11 truthers", "Obama birthers", "Climate change skeptics" or "Holocaust deniers" (and I think you may encounter such people on the eSkeptic web site), then this is a conversation about fanaticism in general, regardless of the particular position(s) that a given fanatic chooses as the focus of his derangement. Fanaticism is a state (or dysfunction) of mind that, like rain, falls on the religious and the non-religious alike.
For sure, some fanatics, as a result of their peculiar mental state, end up saying and/or doing good things (that is, things that a much wider circle of people consider to be generally helpful). It's in the nature of a successful human society that the majority of individuals will tend to be rational and open-minded, allowing for the acceptance of valuable contributions regardless of who contributes.
autotelic adj. (of an entity or event) having within itself the purpose of its existence or happening.
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