Thousands of people independently "remember" an event that never happened

The phenomenon is named after a case where many people independently "remembered" Nelson Mandela dying in prison in the 1980s, even though he was in fact released and lived until 2013, dying as a widely respected statesman.

There are plenty more examples: many people "remember" the wrong spelling of well-known brand names, or misquote lines from movies — identically, independently of each other, despite never having been correct in the first place.

The most widely accepted psychological explanation doesn't involve alternate realities: human memory doesn't work like a video recording, it reconstructs itself from scratch every time it's recalled, and errors in that reconstruction can spread socially when people unknowingly "catch" the same wrong version from each other.

It remains just one hypothesis for why these specific, seemingly random memories become "collectively false" more often than others — how exactly such false memories spread in the internet age is still being studied by memory researchers.