Here are some relevant bits:
"A man with conviction is a hard man to change. Tell him you disagree and he turns away. Show him facts or figures and he questions your sources. Appeal to logic and he fails to see your point."On the "accept new evidence" front, I always say that higher water prices are necessary if we want greater reliability in water services. Some people hear that (reliability good!) before their knee-jerk reaction against paying more kicks in. Some people don't.
We're not driven only by emotions, of course -- we also reason, deliberate. But reasoning comes later, works slower -- and even then, it doesn't take place in an emotional vacuum. Rather, our quick-fire emotions can set us on a course of thinking that's highly biased, especially on topics we care a great deal about.*
We may think we're being scientists, but we're actually being lawyers.
Ironically, in part because researchers employ so much nuance and strive to disclose all remaining sources of uncertainty, scientific evidence is highly susceptible to selective reading and misinterpretation.
...one insidious aspect of motivated reasoning is that political sophisticates are prone to be more biased than those who know less about the issues... These individuals are just as emotionally driven and biased as the rest of us, but they're able to generate more and better reasons to explain why they're right -- and so their minds become harder to change.
If you want someone to accept new evidence, make sure to present it to them in a context that doesn't trigger a defensive, emotional reaction... you don't lead with the facts in order to convince. You lead with the values—so as to give the facts a fighting chance.
Bottom Line: It takes work to really be objective; many people avoid it, and our politics and policies are weakened as a result.
* An example on gun control.