Mistakes can be hard to digest, so sometimes we double down rather than face them. Our confirmation bias kicks in, causing us to seek out evidence to prove what we already believe. The car you cut off has a small dent in its bumper, which obviously means that it is the other driver’s fault.
Psychologists call this cognitive dissonance — the stress we experience when we hold two contradictory thoughts, beliefs, opinions or attitudes. For example, you might believe you are a kind and fair person, so when you rudely cut someone off, you experience dissonance. To cope with it, you deny your mistake and insist the other driver should have seen you, or you had the right of way even if you didn’t.
Kristin Wong in The New York Times.