It’s much more challenging when emotional reactions are involved, as we’ve seen with smokers and cancer statistics. Psychologist Ziva Kunda found the same effect in the lab when she showed experimental subjects an article laying out the evidence that coffee or other sources of caffeine could increase the risk to women of developing breast cysts. Most people found the article pretty convincing. Women who drank a lot of coffee did not.
We often find ways to dismiss evidence that we don’t like. And the opposite is true, too: when evidence seems to support our preconceptions, we are less likely to look too closely for flaws.
The more extreme the emotional reaction, the harder it is to think straight.