Confirmation bias is when you emphasize experience that confirms what you already believed and ignore experience that contradicts what you had believed.
I think this might help to explain a lot of the discussions here and on other forums. Some people have a hard time accepting contradictory evidence while others embrace it. The reason for these differences are probably at least partly genetic.
This a common human trait and probably evolved for very good reasons. If a more experienced person told you what to look for while hunting for example, they would likely be right the vast majority of the time so it would be appropriate to ignore instances where their advice happened to not be right.
It turns out that this tendency is mediated by 2 genes that affect how dopamine is processed in 2 parts of the brain - the pre-frontal cortex and the striatum. The PFC is the part that records incoming advice and allows you to act on it while the striatum records and processes real life experience to extract knowledge.
People with a certain variation in the gene that affects the striatum’s response to dopamine could learn better from experience when no advice was given but engaged in confirmation bias longer than those without the variation.
It’s a really interesting article and pretty short - worth reading.