The fundamental attribution error (also known as correspondence bias or attribution effect) describes the tendency to over-value dispositional or personality-based explanations for the observed behaviors of others while under-valuing situational explanations for those behaviors.
The fundamental attribution error is most visible when people explain the behavior of others. When one interprets ones own behavior, situational factors are often taken into consideration.
Fundamental attribution error is a social/psychological bias, is not a true logical fallacy. However, it is frequently used in arguments or debates.
As a simple example, if Alice saw Bob trip over a rock and fall, Alice might consider Bob to be clumsy or careless (dispositional). If Alice tripped over the same rock herself, she would be more likely to blame the placement of the rock (situational), or that its color camouflaged it.