The Mandela Effect is one of those subjects that can leave you questioning just how reliable your own memory really is. It describes a situation where a large number of people appear to remember the same event, image, name or detail differently from the way it actually exists.
The term was coined after people discovered that they shared a memory of former South African president Nelson Mandela dying in prison during the 1980s. Some even claimed to remember television reports and coverage of his funeral. In reality, Mandela was released from prison in 1990, later became President of South Africa and died in December 2013.
What makes the Mandela Effect so fascinating is that it does not usually involve just one person remembering something incorrectly. Sometimes thousands of people insist they remember exactly the same alternative version.
One of the best-known examples involves the children's book series The Berenstain Bears. Many people are convinced that the name used to be spelled Berenstein Bears. Some say they remember seeing the "-stein" spelling on books they owned as children, yet the official spelling is and has been Berenstain.
Another famous example is the Monopoly Man. Ask someone to picture him and many will describe the top hat, moustache, suit and monocle. There is just one problem — the Monopoly Man does not normally wear a monocle. Some people are so certain that he did that seeing the actual character can feel genuinely strange.
Then there is the Fruit of the Loom logo. A surprising number of people remember the fruit being displayed in front of a brown cornucopia, or horn-shaped basket. The company says its logo has never contained a cornucopia. Yet people continue to claim they remember seeing one on clothing labels when they were younger.
Film quotes are another source of Mandela Effects. One of the most commonly repeated lines from Star Wars is "Luke, I am your father." The actual line spoken by Darth Vader is "No, I am your father." Because the altered version makes more sense when quoted outside the film, it may simply have become the version that stuck in people's memories.
So what causes it?
The conventional explanation is that human memory simply does not work like a video recording. Every time we remember something, our brain reconstructs the memory using pieces of information. Details can be changed, added or influenced by things we have heard since the original event.
If enough people are exposed to the same incorrect information, the same mistake can spread. Films, television programmes, jokes, adverts, conversations and internet posts can all reinforce a version of something until it feels completely familiar.
There is also something known as confabulation. This does not necessarily mean deliberately making something up. The brain can unconsciously fill gaps in a memory with details that seem logical. The finished memory can feel every bit as genuine as something that actually happened.
But not everyone accepts that explanation.
The Mandela Effect has become particularly popular among conspiracy theorists because of the stranger theories surrounding it. One suggestion is that different realities or parallel universes occasionally overlap. According to this idea, people who remember the "wrong" version may actually be remembering something that was true in another timeline.
Another theory involves changes to history itself. Some believe that events in the past have somehow been altered, while certain people have retained memories from before the change occurred.
CERN, the organisation that operates the Large Hadron Collider, is sometimes dragged into these theories. Claims circulate online suggesting particle physics experiments could somehow have changed reality, opened portals or caused timelines to merge. There is no scientific evidence that the Large Hadron Collider has done anything of the sort, but it remains one of the more popular Mandela Effect conspiracy theories.
Others have suggested simulation theory. If our reality were actually some kind of enormous computer simulation, Mandela Effects could supposedly be glitches, updates or alterations to the programme. Again, there is no evidence that this is what is happening, but it certainly makes the subject more mysterious.
Perhaps the most interesting part of the Mandela Effect is how confident people can be about memories that turn out to be wrong. Someone may not simply think that a logo contained a certain object — they may remember where they saw it, what age they were and even conversations connected with it.
That raises an uncomfortable question. If a memory can feel completely real while being inaccurate, how many other things do we confidently remember incorrectly?
Psychologists have demonstrated for decades that memory can be influenced by suggestion and later information. Two people witnessing the same event may remember it differently, while repeated discussion can gradually change what someone believes they originally saw.
That provides a perfectly reasonable explanation for the Mandela Effect, but it does not make the experience any less unsettling when you discover one that affects you personally.
For some people, the explanation is simple: our brains are imperfect and large groups of people can make similar mistakes.
For others, the fact that so many people sometimes share extremely specific memories is enough to make them wonder whether something stranger could be happening.
The term was coined after people discovered that they shared a memory of former South African president Nelson Mandela dying in prison during the 1980s. Some even claimed to remember television reports and coverage of his funeral. In reality, Mandela was released from prison in 1990, later became President of South Africa and died in December 2013.
What makes the Mandela Effect so fascinating is that it does not usually involve just one person remembering something incorrectly. Sometimes thousands of people insist they remember exactly the same alternative version.
One of the best-known examples involves the children's book series The Berenstain Bears. Many people are convinced that the name used to be spelled Berenstein Bears. Some say they remember seeing the "-stein" spelling on books they owned as children, yet the official spelling is and has been Berenstain.
Another famous example is the Monopoly Man. Ask someone to picture him and many will describe the top hat, moustache, suit and monocle. There is just one problem — the Monopoly Man does not normally wear a monocle. Some people are so certain that he did that seeing the actual character can feel genuinely strange.
Then there is the Fruit of the Loom logo. A surprising number of people remember the fruit being displayed in front of a brown cornucopia, or horn-shaped basket. The company says its logo has never contained a cornucopia. Yet people continue to claim they remember seeing one on clothing labels when they were younger.
Film quotes are another source of Mandela Effects. One of the most commonly repeated lines from Star Wars is "Luke, I am your father." The actual line spoken by Darth Vader is "No, I am your father." Because the altered version makes more sense when quoted outside the film, it may simply have become the version that stuck in people's memories.
So what causes it?
The conventional explanation is that human memory simply does not work like a video recording. Every time we remember something, our brain reconstructs the memory using pieces of information. Details can be changed, added or influenced by things we have heard since the original event.
If enough people are exposed to the same incorrect information, the same mistake can spread. Films, television programmes, jokes, adverts, conversations and internet posts can all reinforce a version of something until it feels completely familiar.
There is also something known as confabulation. This does not necessarily mean deliberately making something up. The brain can unconsciously fill gaps in a memory with details that seem logical. The finished memory can feel every bit as genuine as something that actually happened.
But not everyone accepts that explanation.
The Mandela Effect has become particularly popular among conspiracy theorists because of the stranger theories surrounding it. One suggestion is that different realities or parallel universes occasionally overlap. According to this idea, people who remember the "wrong" version may actually be remembering something that was true in another timeline.
Another theory involves changes to history itself. Some believe that events in the past have somehow been altered, while certain people have retained memories from before the change occurred.
CERN, the organisation that operates the Large Hadron Collider, is sometimes dragged into these theories. Claims circulate online suggesting particle physics experiments could somehow have changed reality, opened portals or caused timelines to merge. There is no scientific evidence that the Large Hadron Collider has done anything of the sort, but it remains one of the more popular Mandela Effect conspiracy theories.
Others have suggested simulation theory. If our reality were actually some kind of enormous computer simulation, Mandela Effects could supposedly be glitches, updates or alterations to the programme. Again, there is no evidence that this is what is happening, but it certainly makes the subject more mysterious.
Perhaps the most interesting part of the Mandela Effect is how confident people can be about memories that turn out to be wrong. Someone may not simply think that a logo contained a certain object — they may remember where they saw it, what age they were and even conversations connected with it.
That raises an uncomfortable question. If a memory can feel completely real while being inaccurate, how many other things do we confidently remember incorrectly?
Psychologists have demonstrated for decades that memory can be influenced by suggestion and later information. Two people witnessing the same event may remember it differently, while repeated discussion can gradually change what someone believes they originally saw.
That provides a perfectly reasonable explanation for the Mandela Effect, but it does not make the experience any less unsettling when you discover one that affects you personally.
For some people, the explanation is simple: our brains are imperfect and large groups of people can make similar mistakes.
For others, the fact that so many people sometimes share extremely specific memories is enough to make them wonder whether something stranger could be happening.