Fundamental Attribution Error

Fundamental Attribution Error is the tendency to evaluate another person's behavior as personality traits, while ignoring situational factors. For example, you notice a man giving money to a beggar by the street. We would be quick to label the man "generous" (a personality trait), without considering situational factors, like if the deed was done in private or in public, in front of a few or many people, if the money came from someone else, etc. All those other possible situational factors would mean that the person may not actually be "generous." According to the subjectivist perspective in Psychology, this error in perception occurs as a result of Western emphasis on personal agency, that is, westerners tend to consider behaviors as choices; consequently, they fail to see and consider the influence of situational factors.

See also: Overjustification Effect (how we tend to evaluate our own behavior by emphasizing situational factors more than our own personal causes).