Challies.com posted comments on an article by Al Mohler recently. One paragraph in it hearkens back to comments I made here and here, which others have also commented on, noted here. Here's that paragraph:
When we affirm the doctrine of the fallenness of man, we affirm that through the Fall we have been corrupted in every way. The depravity of man extends to every area of his being so that nothing remains untouched. We are unable to use our minds without allowing emotion to interfere with reason. Clearly this poses a threat to intellectual integrity. "The reality of confirmation bias and its threat to intellectual integrity is one reason that Christian thinkers must read widely and think carefully." Christians bear the responsibility of knowing their sin and thus knowing their proclivity for all manner of sin--even the sin of confirmation bias. For if we are able to admit that confirmation bias is a result of the Fall, we must also admit that it likely comes naturally to fallen men and women and that we are all likely to slip into it from time to time. I did not have to think long or hard before seeing areas where I am prone to make snap judgments and to allow emotion to override more measured reason. And, as the subject of discernment has been much on my mind in recent days, I also see how people to seek to be discerning may be particularly prone to this bias.
I also posted on having friends who disagree with you a while back, which seems to connect in with Challies' thoughts too.
Finally, the question that came to my mind is this: Before the Fall, were Adam and Eve perfectly logical, using "measured reason...without allowing emotion to interfere"?
Other posts: Reason v Emotion