I knew a man who was chess champion of California who claimed that neither he nor his father could visualize anything. His father was a taxi driver in London, and long knew that the other drivers had mental maps, whereas he had to memorize lists of street names in just the right order. My friend, by the way, could also play blindfold chess just fine. He'd merely remember that "e7 is attacked on the diagonal from g5", presumably from long practice with the sequence e-f-g, 7-6-5. He lamented that his inability to visualize put an upper limit on his chess ability, and given how hard he worked, I believe it.
Galton was astonished that many scientists of his acquaintance did not visualize. Judging from Galton and other things I've read, the ability to visualize is more common today. TV, maybe. Please try to picture this without thinking of the old joke: "A man walked down the street, and turned into a drugstore". (The joke, of course, is that people do not become drugstores.)
Now did you happen to notice which side of the street he was walking on (left or right), and whether he was walking towards or away from you? The problem for those of us who use visualization for almost all our thinking, is that we must add irrelevant and often distracting information, which can be costly in math and science.
Robin asked "If lawyers and academics can disavow these ancient practices, while still embracing a true essence of law or academia, why can't religious folks disavow ancient religious practice in favor of some true essence that makes sense in modern terms?"
In "Retreat To Commitment", Bartley described the (at the time) very large and very powerful group of liberal Protestants who did so disavow ancient views, and look what it got them: demographic replacement by the faithful, by the Evangelists. It only looks like religious folks are different. In truth, after a while we no longer see many folks representing those newer, weaker memes. Isn't it just normal evolution?
Bob wrote "The person who calls himself a global warming skeptic... after reading a couple of books and a few articles arguing for [such skepticism] will often acknowledge that if he'd started by reading books advocating alternative views, then he would not have come to be a global warming skeptic..." This is one mechanism, but sometimes positions just "feel right" to people, i.e. in agreement with their predisposed visions, or traits.
Also it seemed to me that by asking of people that they examine as many arguments opposed to their view as they examine in alignment with their view, you would also be demanding a similar objectivity from scientists. But as has been said often, scientists are only human. They pursue their hunches (conjectures); and natural selection knew what it was doing when it made all of us normally tend to do the same.
This is not to strongly discount a goal of overcoming bias, but is to confirm a point doubtlessly made here before, that not only does bias exist for a reason but can in many instances be optimal for achievement or survival. Admittedly, truth seeking and achievement may be at odds with one another at times.