Is the ‘Mandela Effect’ Science, Science Fiction, or Mass Delusion?

What some dismiss as misremembering could be a hint of alternate realities

Photo by Jon Tyson on Unsplash

IfIf you follow unusual theories online, you’ve probably heard of the Mandela Effect. It’s a phenomenon in which a large group of people remembers a different history than that which we “know” to be true. I put “know” in quotes because of the underlying questions that the Mandela Effect raises about the nature of reality, memory, and timelines.

The term was coined by blogger Fiona Broome in 2009, after hearing many stories of people who “remembered” Nelson Mandela dying in prison in the 1980s. A quick internet search will tell you that Mandela won the Nobel Peace Prize in 1993, went on to become the first President of South Africa after apartheid ended in 1994, and died in 2013. At least in our timeline.

The Mandela Effect wouldn’t be a big deal except that it seems large numbers of people have the “other memory” — it’s as if there was a separate timeline that they recall, but now are all stuck on “our” timeline. Is this possible? Or are they all simply misremembering the same thing?

Popular in Science Fiction

Though it was named only recently, throughout history there have been countless examples of this phenomenon. The possible explanations put forth have ranged from mass delusions, to false memories to parallel worlds, and my personal favorite, the simulation hypothesis. If these explanations sound like science fiction, it’s because the idea of multiple timelines converging and diverging (usually because of a time traveler or two) has become a common trope in science fiction.

In every good time travel story, someone goes back in time and attempts to change something. Whether that person is the villain (as in the show Timeless) or the hero (as in Dr. Who) is up for interpretation. In almost every case, though, changing the past ends up changing something in the present. Hopefully for the better, but sometimes for the worse. The people who went back in time usually remember what the timeline was like beforehand, but everyone else does not. They only know the new reality, blissfully unaware that something has “changed.” When it’s Dr. Who and his companions saving the world from certain takeover by a rogue time lord, for example, or Sarah and John Connor prevent machines from taking over the world, this lack of memory on the part of the general public is the desired effect.

Is the Mandela Effect some kind of glitch in the matrix?

But sometimes this change is not desirable, leaving those who “remember” both timelines in a dilemma. In a famous episode of Star Trek: The Next Generation called “Yesterday’s Enterprise,” Captain Picard and his crew on the Enterprise-D come across a time-traveling version of its predecessor, the Enterprise-C, which had been presumed destroyed during a confrontation with the Klingons. Picard and crew decided to save the Enterprise-C, and as a result of that decision, in an instant, everything changes. The whole federation is no longer a peaceful organization and Picard is a war-time captain. Only the alien Guinan (played by Whoopi Goldberg), who has a kind of sixth sense about reality and timelines, sees that something is wrong and that reality has changed.

Figure 1: An alternate timeline in a famous episode of “Star Trek: The Next Generation,” caused by mucking with time.

While there are plenty of examples of a small group of people remembering both versions of “reality” in science fiction, there aren’t as many examples where one group (say half of humanity) remembers one timeline and another group(say, the other half) remembers another timeline, offering two conflicting views of reality.

Science fiction writer Philip K Dick was a fan of the theory that reality was somehow being changed, in big ways and in small ways. In fact, when I interviewed his wife, Tessa B. Dick as part of my research for my book, The Simulation Hypothesis, she told me that he believed in the timeline where the Axis powers had won the war, and wrote The Man in the High Castle (now a popular Amazon series) because of his memories of both timelines — including our timeline where the Allies won the war. He also claimed that sometimes there were much smaller changes being made to reality, and we weren’t supposed to remember these “adjustments” (like a chain light being changed to a light switch), which motivated him to write “The Adjustment Team,” a short story that was the basis for the blockbuster movie The Adjustment Bureau starring Matt Damon and Emily Blunt.

Was Philip K. Dick Right? Is the Mandela Effect some kind of glitch in the matrix? Or is it simply explainable as a case of a few people misremembering some event? Before we look for answers to that question, let’s look at the various categories of events that are being misremembered.

More examples of the Mandela Effect

On her website, Fiona Broome and others have collected many examples of this effect, where a large number of people remember things differently than they actually happened. Broome herself notes that the phrase has gone mainstream. It was even referenced in the recent reincarnation of the X-Files and has become an internet meme.

In the Empire Strikes Back, many remember: “Luke, I am your father,” but what Darth Vader actually said was “No, I am your father.”

I like to divide these examples into four categories, with various levels of believability:

  1. Major Events/Deaths. The most startling examples are ones that involve non-existent events that many people remember happening, such as Mandela’s funeral. Similarly, many people remember the preacher Billy Graham dying in the 1990s and Bill Clinton speaking at his funeral. These types of “historical events” are perhaps the most troubling aspect of the Mandela Effect because they are harder to explain away as a simple error.
  2. Television and Movie Related. Both movies and TV (especially before the proliferation of cable TV channels and the internet) are one part of our modern culture that is pretty universal, especially since movies are now released internationally on the same dates. There are several subtypes of the Mandela Effect related to movies and TV. The simplest is misremembering of lines — for example, in the Empire Strikes Back, many remember: “Luke, I am your father,” but what Darth Vader actually said was “No, I am your father.” Sometimes there are scenes that people remember but didn’t actually exist — for example in the movie Risky Business, many remember Tom Cruise dancing around in his underwear, wearing sunglasses. In fact, he wore sunglasses in the movie, but not in that scene. Probably the most startling example of the Mandela Effect in this arena is that many people remember a movie from the 1990s starring Shaquille O’Neal called Shazaam. The movie was actually called Kazaam.
  3. Religious/Scripture. There is a whole subculture now that is devoted to seeing “changes” in the Bible from when they learned the verses as kids. One of the most troubling is when people remember Bible verses differently. Now if it was simply a random phrase from a random book, that would be one thing, but great effort is made by religious people and preachers to remember passages from the Bible exactly as they are written (or at least as they are translated into your language). One of the most famous is “The lion will lie with the lamb.” — if you look in any Bible at Isaiah 11:6, it actually says “The wolf will live with the lamb.” There are people who believe someone or some force is actually changing the Bible verses by messing with our reality, and there are many websites dedicated to pointing this out. Has the Bible actually changed since it was memorized by these religious people?
  4. Miscellaneous and misspellings. The final set of misremembrances includes several subtypes. One of the most common examples of the Mandela Effect is a word that isn’t spelled like we remember it being spelled. For example, the Berenstain Bears is remembered by many people as the “Berenstein Bears.” Also, many people remember the Monopoly guy wearing a monocle, but he never did. Mr. Peanut, on the other hand, does have a monocle. And do you remember Jiffy peanut butter? It never existed. It’s always been called Jif peanut butter.

What causes the Mandela Effect and is it real?

A lot of mainstream scientists dismiss the Mandela Effect as simply a matter of imperfect memory. But what is the nature of this misremembering that would make so many people so sure of their memories, complete with details that are unlikely to have been made up?

Though there has been quite a bit of research on how we form memories and store them in the brain, we still don’t fully understand how memory works. This means that any theory about the Mandela Effect must remain just that: a theory. Let’s take a look at the prevailing theories that have been presented about this.

It turns out that upon examination, although many commentators have done so, I don’t think you can make sweeping generalizations about the origins and meaning (if any) of the Mandela Effect. The reason I like to divide the examples into categories is that it’s possible that different categories might lend themselves more easily to a particular theory or explanation.

Let’s start with the simplest explanations of the simplest events and then move on to the more complicated ones, which may require more complicated theories to fully explain.

1. Simple Error

The simplest examples, including wording and grammatical misremembering, such as the Berenstain Bears case, are most likely the result of simple errors. There’s a common exercise where you ask people to read aloud this sentence about Paris in the springtime:




You might not notice the extra word in the sentence unless you point to each word as you say it. When we’re reading, we often skip words, or allow our minds to fill them in. A 2011 study in the Journal of Experimental Psychology: Human Perception and Performance showed that words that are skipped are filled in 8% to 30% of the time. An important factor in this study was the predictability and the length of the word — since the repeated word, in this case, is very short and common (“the”), it often gets overlooked by a certain percentage of people. What about the letters? As Arizona State University associate professor Gene Brewer, PhD explained to Mental Floss, “When you recall an event, you use memories around it, taking elements or pieces of other events and fitting them where they make sense.” A likely explanation for the misspelling of Berenstain and Jif is because kids may have misspelled it, and even newspaper articles and school publications may have misspelled it.

It’s very likely that small misspellings and miscellaneous name remembrances can be explained by these types of “memory hitches,” but what about bigger events?

2. Intentional False memories

This is where we start to get more speculative on the reasons and causes of the Mandela Effect. Psychologists have found that telling people about a false event can cause them to remember it as true. This has happened in court cases and in test experiments. University of Virginia professor of psychology Jim Coan created the “lost in the mall” procedure when he was an undergraduate in Washington. Coan described childhood events to his family members, including one about his brother getting “lost in the mall.” His brother later took that to be a true event, even though it wasn’t. The technique was applied to a larger number of people by his professor, psychologist Elizabeth Loftus, who found up to 25% of the participants remembered something that was false.

While there may be some validity to the idea that false memories can be implanted this way, this would mean someone was specifically trying to plant these false stories so that a large number of people might remember them as “true.” In the case of Mandela’s death, this doesn’t sound like a reasonable explanation. Unless there were multiple news outlets, including newspapers, TV, and radio, that were all “in on it,” either reporting his death in the 1980s (or saying later that they reported his death in the 1980s), this explanation just doesn’t hold up.

Are there other ways that false memories can come together? In the same Independent article, they describe the Deese-Roediger-McDermott procedure which allows for closely related words (like “bed” and “pillow”) to suggest other words (like “sleep”) which weren’t in the list, but which participants remember as having been on the list. This could be due to a failure of memory and how it works through association. But again, while this explanation seems to hold true for simple errors, it is unlikely that it could be responsible for major events, where people remember Bill Clinton and other presidents honoring Billy Graham at his funeral, and some remember discussing it with relatives well before his actual death.

A more science fiction explanation would be that some super-psychiatrist outside of our normal purview was implanting false memories into the brains of a subset of the population as part of some experiment. Now we are back in the realm of Philip K. Dick’s novels, where false memories feature prominently. These ideas were carried forward in movie adaptations of Dick’s work like Blade Runner, where the android Rachel is given false memories of a childhood she never had, and Total Recall, where Arnold Schwarzenegger’s character is able to take a “vacation” by simply implanting memories in his mind.

What purpose would there be for implanting false memories in a large percentage of the population? We can only speculate.

3. Multiple Timelines and Time Travelers

A popular explanation, which many believe to be squarely in the realm of science fiction (which of course is sometimes whether future science will end up), is one of multiple timelines. In this explanation, the events that people remember differently actually happened differently, but on another timeline. Notice that this explanation doesn’t strictly require an infinite number of universes (the Multiverse concept) by itself — it just requires more than one timeline which “merges” with the original timeline or gets changed, even after the fact, by time travelers.

Speaking of Philip K. Dick, when I interviewed his wife Tessa, she told me that he believed he was in contact with some beings who could “change the timeline.” In addition to changing the timeline regarding World War II, they claimed to have prevented the assassination of John F. Kennedy in multiple places, including Orlando and Dallas. In each of these alternate timelines, JFK was still assassinated in another place, or there were other undesirable outcomes (such as a nuclear war), so they let the JFK assassination in Dallas timeline (the timeline most of us remember) proceed. It would be interesting to determine if there were any groups of people who remember JFK being assassinated in a city other than Dallas. A quick search on the internet reveals that there are many who remember the details of the assassination differently (including some who remember seeing a gun in Jackie Kennedy’s hand, which obviously didn’t happen, at least in our timeline).

Figure 2: Timelines A and B merging together

Figure 2 shows how the Mandela Effect can be explained by requiring two timelines, which are merged together to form one surviving timeline. If Timeline B is the “consensus timeline,” those who were part of timeline A will remember events differently from the rest of the world.

What could account for this discrepancy? Now we get back into the messy areas of consciousness and memory — even though the timelines were merged, memories weren’t automatically changed (like they were in Star Trek: TNG’s episode, “Yesterday’s Enterprise”).

Another question: If Timeline B is the consensus timeline, what happened to timeline A? Did it disappear altogether or does it still exist, perhaps with the Mandela Effect in that timeline, and some subset of people remembering Mandela having lived until 2013, when the consensus view is that he actually died in the 1980s in prison.

Following on the Dick-inspired approach, one esoteric explanation that fits into the multiple timelines theory is that there are time travelers who go back and “change” things, causing us not to remember the previous timeline. In this example, Mandela did die in the 1980s in prison but this led to an unsatisfactory timeline, so some time travelers went back and “changed history”, preventing him from dying. But through a glitch in how our consciousness and memory work, a certain percentage of people still remember the old timeline, which no longer exists. This is shown on the right side of Figure 2.

4. Parallel Universes and the Multiverse

A related explanation of quantum indeterminacy in quantum physics is that there are multiple parallel universes and that the universe branches each time a decision is made. While this sounds like science fiction, it is one of the accepted possible explanations for the collapse of the probability wave in quantum physics, which still doesn’t have, after many decades, a satisfactory explanation. If there are multiple universes — what’s referred to as the Multiverse theory in popular culture (and the MWI, or Many Worlds Interpretation, in academia) — then there would be universes in which an infinite number of possibilities happen, including the premature death of Mandela, Graham, and perhaps many other prominent figures.

Could the Mandela Effect simply be about remembering one of the many universes? Since the role of consciousness is not well understood, the relationship between a person in Universe A versus Universe B has not really been defined in the multiverse model. Since they theoretically branched out from the same person at some point, could they share memories or cognitive functions?

Note that in this interpretation, it’s a little bit different than the time traveler or single timeline thesis (where there is only one timeline at a time, which is being manipulated). In the multiverse case, all possibilities exist as separate universes. We just happen to be in the one where Mandela was alive until 2013, while the other ones still exist.

5. The Delayed Choice and the Future Affecting the Past

If parallel universes weren’t strange enough, the strangeness of quantum physics has produced even stranger theories, some of which have been confirmed by experiments. In the 1960s John Wheeler proposed the delayed choice experiment, where he wondered if a choice made in the future could affect the past. If a particle goes through one of several choices in a double-slit experiment, and then has to make further choices afterward, could the observation of one of those choices in the future, actually affect which of the slits it went through in the past? The answer seems to be yes. An Italian research team performed a version of the delayed choice experiment where a photon went through one (or both slits if it was in waveform) and then was sent (or not sent) to a satellite over 1,000 miles away. It turns out that the observation of the particle on the satellite seemed to impact which slit it went through.

Adam Curry, a former researcher at Princeton Engineering Anomalies Research lab (PEAR), postulated that the Mandela Effect could be happening as a strange version of the delayed choice experiment. Curry attempted to reproduce the effect by having a group of people go to either park A or B on Monday, and have a future event (let’s say the flipping of a coin on the following Friday, for example), influencing which park they went to. While this wasn’t a formal peer-reviewed research project, and the results weren’t conclusive, this is an area that deserves more attention. Is it possible that by observing Mandela becoming President of South Africa and the ending of apartheid, that affected the past event: in this case, we are the time travelers and no TARDIS or time travel device is required!

6. The Simulation Hypothesis

We now come to what is my favorite explanation for the Mandela Effect: that we are living in a computer generated reality, or a simulation, like a video game, and thus like any game, the “parameters” can be changed, but just because the parameters can be changed doesn’t mean that it’s a perfect process.

Like a warcraft server that can be reset, the simulators have control over certain events in our ongoing MMORPG. Notice that this doesn’t preclude some of the other possibilities here, it simply provides an explanation of how the timelines might be changed without requiring time travelers, per se.

There’s a whole branch of mathematics, called chaos theory, that was formed by noticing that simulations can have radically different outcomes with slight variations in initial conditions. This is the famous “butterfly” effect (where a butterfly flapping its wings in Shanghai affects the stock market in London the next day). The more formal name is “sensitivity to initial conditions.” The simulations that chaos theory was concerned with were typically deterministic processes — i.e. processes which don’t necessarily have random values or free choice, yet they still required simulations to run through to get to the eventual outcome that resulted from any change, no matter how small.

In the Simulation Hypothesis, we could all be Non-Playable Characters (NPCs) in a deterministic process with some level of randomness that the simulators are watching to see “where we end up.” Whenever there is a desired result that they don’t like, they simply restore the game to a previous point and tweak the parameters. Through some glitch in the code, a certain percentage of people may still be accessing memory locations that were present on the previous run of the simulation (and for whatever reason haven’t been rewritten). This could be because of a bug in the code, or as any software developer will tell you, you simply leave old values in memory without “erasing them” and write the new memories to a different location. In the language of computer science and algorithms, an inefficient garbage collection algorithm could be enough to account for the Mandela Effect.

By looking further into quantum theory and simulation theory, we just may find that the Mandela Effect isn’t a strange anomaly.

Even in the version of the Simulation Hypothesis where we aren’t all NPC’s, which I call the RPG version (role-playing game), or Matrix version, consciousness is more complicated than simple memory locations in a computer chip. In this version, consciousness exists outside of the simulation — just like you can remember different games of chess or World of Warcraft, it’s possible that the people who remember a different timeline are accessing memories of their “player” rather than the “avatar” that is being played in the current run of the simulation. Because the players have some level of free will, the simulators would need to change some parameters and “see how the game plays out.”

In this version, the different timelines or parallel universes exist either as possibilities or as “previous runs” of the simulation. There is an interpretation of quantum physics that says that strangeness of quantum indeterminacy, the wave vs. particle question, only exists because the wave is what would happen if you ran the same process multiple times, and we are only seeing “one run” of the process. This implies that reality might be a computer-generated simulation where every single event could be “rerun.”

It’s worth more investigation

While many have dismissed the Mandela Effect as simple memory errors, I believe it’s worth looking at it further from both a scientific and technological point of view. By classifying different examples of the effect, we can narrow down the cases where there might be a reasonable, trivial explanation versus the cases where simple misremembering is not enough to explain what a large group of people remember. By delving into this in a serious way, we can learn more about human consciousness and possibly more about the strange, mysterious universe that surrounds us.

By looking further into quantum theory and simulation theory, we just may find that the Mandela Effect isn’t a strange anomaly, but is providing us with edge cases that we should pay attention to. Just like Einstein’s insights about relativity happened at the edge cases of Newton’s theories about how the universe worked, it’s possible that the Mandela Effect is providing us with edge cases that could revolutionize our understanding of how the universe works and our place within it.

Rizwan Virk is the founder of Play Labs @ MIT, a video game accelerator, and the author of The Simulation Hypothesis: An MIT Computer Scientist Shows Why AI, Quantum Physics and Eastern Mystics All Agree We Are In a Video Game

The Simulation Hypothesis, Play Labs @ MIT, Startups/VC, Sci Fi, Bitcoin, Consciousness, Space, Video Games: visit

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