Hindsight bias is a psychological phenomenon in which someone claims to have predicted the outcome of an event and the perfect course of action only after the event has taken place. For example, people often recall their predictions for outcomes of an event much more strongly if their prediction comes true.
Hindsight bias can effectively alter one's grasp of the past. The change is not dramatic, but results in people being more sure of themselves once they have been proven to be correct. This logical fallacy may result in overconfidence, making people think that they have a special skill for predicting events or understanding situations.
In some cases, hindsight bias can actually affect future performance. If an individual feels confident in one prediction, such as getting a good grade on a test, that confidence may change future study habits. Perhaps the student does not put as much time into studies because he or she assumes the next exam is going to be easy. This phenomenon is called a self-fulfilling prophecy and is closely related to the hindsight bias.
One way to overcome hindsight bias is by keeping a journal. If someone writes down their uncertain feelings before the outcome of an event, he or she can refer back to the journal after the event's conclusion. This reinforces the uncertainty felt while writing, reminding the individual not to give in to the hindsight bias.