I believe you're confusing arrogance and closedmindedness. There is a correlation between openmindedness and intelligence. I do believe openmindedness is a form of rationality. I'm not sure how good rationality training is at increasing it. Personality Psychology indicates Openness to Experience is a fairly stable trait; not one that can be taught.
I believe you're confusing arrogance and closedmindedness.
Well, maybe that's the question. They're different, and you can have one without the other, but do they cooccur above chance? Maybe arrogance reduces your exposure to the occasional clever ideas that will inevitably come from people you've dismissed. That isn't closemindedness, it something more like as-if-closemindedness, but it would come to the same thing.
I have this belief that humility is a part of good critical thinking, and that egoism undermines it. I imagine arrogance as a kind of mind-death. But I have no evidence, and no good mechanism by which it might be true. In fact, I know the belief is suspect because I know that I want it to be true — I want to be able to assure myself that this or that intolerable academic will be magically punished with a decreased capacity to do good work. The truth could be the opposite: maybe hubris breeds confidence, and confidence results? After all, some of the most important thinkers in history were insufferable.
Is any link, positive or negative, between arrogance and reasoning too tenuous to be worth entertaining? Is humility a pretty word or a valuable habit? I don't know what I think yet. Do you?