Fundamental Attribution Error is when you blame a person's characteristics for their actions instead of the situational factors surrounding them. We all make this error and it's similar to judging a book by its cover.
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Slide 2
Not surprisingly, if we were to judge ourselves in those situations, it would be the other way around. We would take the situational factors into account as reasons for our actions and not blame it on a flawed personality trait (and judge our own book by its cover).