Hindsight bias, also known as the knew-it-all-along phenomenon or creeping determinism, is the common tendency for people to perceive past events as having been more predictable than they were.

The misinformation effect occurs when a person's recall of episodic memories becomes less accurate because of post-event information. The misinformation effect has been studied since the mid-1970s. Elizabeth Loftus is one of the most influential researchers in the field. One theory is that original information and the misleading information that was presented after the fact become blended together. Another theory is that the misleading information overwrites the original information. Scientists suggest that because the misleading information is the most recent, it is more easily retrieved.