Confirmation bias
The habit of noticing and remembering what fits what we already believe, and forgetting what does not.
Also: selective memory, hits and misses, belief perseverance
Psychologists use the term for a general feature of human thought. When a person expects a charm, an omen or a prophecy to be right, the hits are remembered and the misses fade. The dream that came true is retold, while the hundred that did not are forgotten. Peter Wason's experiments in the 1960s showed that people tend to look for evidence that confirms a rule rather than tests it. The effect is not limited to magic, and believers and sceptics alike are subject to it. Researchers suggest that keeping a written record of predictions and outcomes is one way to see it at work, and it is also used to explain how rumours and conspiracy belief persist.