You learn a new word, then suddenly see it everywhere. Why?
Buy a new car and the roads seem full of the same model. Learn an unusual word and it pops up all week. The world hasn't changed; your attention has. Psychologists call it the frequency illusion, and it quietly convinces us that coincidences are patterns.
The frequency illusion is the sense that something you have only just noticed is suddenly appearing far more often. It has a second, odder name, the Baader–Meinhof phenomenon, which comes from a 1994 letter to the St. Paul Pioneer Press newspaper. The writer, Terry Mullen, described mentioning the name of a German militant group once and then noticing it repeatedly; other readers wrote in with their own examples. The more descriptive name 'frequency illusion' was coined in 2005 by the Stanford linguist Arnold Zwicky, on his blog.
Zwicky put the effect down to two familiar processes. The first is selective attention. Your brain is constantly filtering an overwhelming stream of information and letting through only what seems relevant. Once something new becomes relevant, the filter starts letting it through. The thing was always there; you are simply seeing it now.
The second is confirmation bias, our tendency to notice evidence that supports what we already suspect and to overlook what doesn't. Once you think 'this word is everywhere', each new sighting feels like confirmation, while the many days it doesn't appear go unrecorded. A companion effect, the recency illusion, makes things worse: having only just noticed something, we tend to assume it must itself be new.
Some researchers link the illusion to a split-category effect too: break a category into smaller parts and people tend to estimate more of it overall. The source also notes a modern twist: recommendation algorithms that tailor what we see may make the experience more common. The practical upshot is humbling. A feeling that 'this keeps happening' is weak evidence on its own. Before seeing a trend, or a sign, it is worth counting.
Source: Wikipedia — Frequency illusion · Text summarised from Wikipedia (CC BY-SA 4.0)
