To describe somebody as a tunneler might be helpful. A similar expression would be to be in his own bubble. You are highlighting the Alice in Wonderland aspect more that I think most adult males have found themselves in. Where you think you found the ultimate key/wisdom and everything can just be measured by that including yourself.
A 'bubble' usually implies that you are just repeating what you hear from your surroundings. In your case you point out that some can have opinions that are not mirrored by their surroundings but proven through debate. I can't help but to think of myself. In school I was crushing everyone in debates, the best could merely keep up with me, but looking back from where I stand now politically, I think I was full of shit, despite the success, took me some time and some pride to swallow though.