You can't go home again if "you"
"You say you don't have any objectives? That's tragic, you know, but you are still confused. The fact that you are empty means that you can fill that emptiness with as much as you want. You happy person, where's a better future than that?"
What defines "you"? The concept of identity, never mind the search for it
, is a complicated question that fiction tries to answer. Beware though, fiction likes to throw us curve balls.
Is it your memories? Those can be removed
(Oh, are there ever
so many ways
.) How about your personality? Well, that changes over time naturally
like it or not, but then again you can play someone else
and find you like being them better
. Is it your body... or your humanity
? Less luck there, if it isn't a body swap
it's a gender swap
or something much worse
. Does the Soul
have anything to do with this? Are you still "you" if you reincarnate?
Then again, most of the previous changes are negative, but what about positive
alterations? Flowers for Algernon Syndrome
and What Measure Is a Non-Super?
make you wonder just how valuable you are when you gain... or lose... faculties. The Mind Is a Plaything of the Body
, after all.
Don't let our meandering college philosophy depress you. After all, every non-nerve cell in your body is replaced in seven years (some die and get replaced, some go through mitosis and divide into two... wait, would that make those the same cell or two new ones? Does the original count as dead after that? Argh!), and change — the evolution of a personality — is natural. So you might as well wonder if you are the same "you" from five minutes, days, years, or decades ago.
Not to be confused with an Assimilation Plot
, in which your identity is subsumed into a Hive Mind
. Compare Split Personality Merge
, where two personalities become one, and Mental Fusion
, where separate minds briefly become one. See also Amnesiac Lover
, who doesn't know how to love back after becoming an amnesiac. Grand Theft Me
can happen if said identity was stolen. Living in a society where you can't have a real identity is Individuality Is Illegal
. See also Quest for Identity
. Compare Lost in Character
, where an actor becomes lost in a role.
open/close all folders
- Carefully analyzed in Magical Girl Lyrical Nanoha, where the entirety of Fate's Dark Magical Girl role stems from being considered a mere tool by her "mother" and having the identity of her genuinely loved dead sister, to which her "mother" hates to no end.
- This is one of the central points in Serial Experiments Lain. Lain is a painfully reclusive girl who barely speaks to anyone, but what about the Lain who spends every night drinking and hooking up at the clubs? Later, when some of The Men in Black are asking her some questions, she asks "Who are you?" They turn the question around, and ask her when her father was born. She can't answer, because her family is fake and she was never human in the first place.
- This is also her source of angst in the final episode, when she wonders who she is after erasing herself from everyone's memories, discarding her physical body, and altering history so she was never there.
- The point of most Instrumentality plots - as seen on Neon Genesis Evangelion and Yu-Gi-Oh! GX among others - is to relieve humanity of the burden of isolation that comes with individual identities.
- A major theme of Kara no Kyoukai. Shiki wakes up after a two year coma and is only able to feel " " - literally nothing, emptiness. She is unable to connect herself to the "her" from her memories, and no longer has the "split personality" that she had been born with to keep her company. Her finding something to continue living for is a major issue for the rest of the series.
- Also done on a lesser scale with Tohko, who at one point created an exact duplicate of her body, down to the last detail, which made her realize that her own individuality was completely meaningless, as that body could exist as her on its own. She links it to her consciousness and sets it to wake up the instant her current body dies, so it quite literally is her, complete with memories and everything.
- In Monster, the orphanage Kinderheim 511 existed solely to do this to children of criminals and political undesirables in East Germany. They bit off more than they could chew with Johan, though.
- A darker take of Ranma's situation could lead to this. Additionally, in an anime-exclusive episode, Ranma banged his head hard after being swatted into the Koi Pond, and was taken over by an alternate personality that thought it truly was a girl, with almost insultingly stereotypical attitudes and tastes, in a situation that was one part this to one part Laser-Guided Amnesia. Fridge Logic on what might be going on with Ranma's real personality while the "girly Ranma" is in control can be terrifying if you're a fan of Ranma...
- Fullmetal Alchemist: As Envy said, the tortured souls that compose his body perished a long time ago in mind and body. This may be true for all other souls that make up the Philospher's Stone.
- Al is also drawn into a Heroic BSOD by Barry by implying that his memories and body were just crafted by Ed.
- Happens for real with Pride, who loses his memories and personality, and assumes the role of Selim Bradley.
- Light's Memory Gambit in Death Note could be seen as an example of this- when he relinquishes ownership of the Note, he becomes a genuinely different, better person. Of course, it doesn't last.
- What he becomes is himself, minus all Kira-related Character Development, but plus the character development of having encountered someone just as smart as himself (L may be smarter, but he handicaps himself with rules so it's hard to tell) and having something interesting going on in his life. Being totally selfish, he wouldn't have become Kira, gambling with his life and self, if he hadn't been bored to the depths of his soul, so there is a distinct difference even from the bright-eyed Light in the early chapters, let alone Kira at his height. Is this still 'him'? Maybe, maybe not. Hence all the questions at the top of the page.
- A possible outcome of repeating many Groundhog Day Loops in the When They Cry multiverse. At best you come out insane.
- This is one of the driving forces of Blue Drop: Tenshi no Bokura. The protagonist's male best friend had his brain downloaded by aliens and copied into the body of a female alien, and his real body was cremated. Over the course of the series the copy- and thus the human and masculine identity- slowly fade away, leaving behind the most definitely not human original inhabitant of the body. Worst of all, the human identity doesn't fade away entirely, and by the end, the creature that is left is too human to retain its alien identity, and too alien to retain its human identity.
- This is an effect of the conditioning given to the cyborgs of Gunslinger Girl, where they are turned into blank slates who can be programmed to perform any function needed and it ensures loyalty to The Handler. That's when it's deliberate, like when Jose finally crumbles under all of the stress of the job and keeping up pretense with Henrietta that he Took a Level in Jerkass and resets her with conditioning and use her to replace Beatrice, the unit's bomb-sniffing cyborg. This also happens to Angelica, whose faulty conditioning and implants causes her increasingly forgets things until her death.
- It also happens when the girls are first turned into cyborgs, as all of them are plucked from near death and it's best to condition over their mental trauma, although Rico still remembers what it's like before the Agency found her and Triela knows that she was found in Amsterdam.
- In Spirited Away, Yubaba binds people to her service by stealing their names and memories. Even Chihiro who was there for less than a day was already to beginning to forget her real name.
- In The Secret Agreement, while Kyuusai treats Yuuichi's blood finally awakening as the finding of an identity with the clan (which steals other people's life force in order to live), Yuuichi feels like his identity and all the meaning in his life has just been wrenched away. Particularly since it means his love for Iori is a delusion meant to enable Yuuichi to kill him, Yuuichi doesn't know how to navigate between what he thinks are real feelings and what his uncle says he must do.
- The driving force behind Kabuto's villainy in Naruto. Kabuto was orphaned and suffered a head injury that robbed him of his memories at a young age, so he doesn't even know his original name or family. The Leaf village employed him as a spy, which meant subsiding his own personality into cover identities on a regular basis. Then he got brainwashed by Sasori and turned into a puppet. He was eventually freed by Orochimaru and found peace of mind acting as his second-in-command, but lost that after Orochimaru was killed. Kabuto eventually decided to focus on attaining power surpassing any other ninja in an attempt to bring meaning to his nameless existence.
- "Tobi" attempts to invoke this about himself, burying his old identity under layers of Obfuscating Stupidity and other lies. When it turns out he's neither the harmless goofball or the stoic Uchiha Madara, he claims that he doesn't have a real self and is just a vessel for his master plan. "I'm no-one, and I don't want to be anyone."
- Oz Vessalius from Pandora Hearts suffered an identity crisis very early in life after his father completely rejected him. Being the type of person that he is, he was able to eventually bounce back from that blow, although not entirely. As of Retrace LXXIV, however, he seems to have lost his sense of purpose as well as any semblance of self-worth, all of which is the result of everything that Jack did to him in the previous chapters.
- Sasami of Tenchi Muyo! had this. After a major fall when Ryoko invaded Jurai, she was rescued by Tsunami and bonded with her. For over 700 years, she wanted to tell someone the truth, that she was nothing more than a vessel and that the real Sasami was dead, but always stopped because she was afraid that if she did, they'd abandon her. Thanks to a mistake on her part, the others learn the truth, but quickly reassure her that they'd still love her. However, when Sasami passes out from all of the excitement does Tsunami reveal the truth - she never died that day. The trauma from the fall and rescue caused her to think that. She reassures everyone that when Sasami's older and can handle the truth, she'll learn it.
- In One Piece, on the island of Dressrosa the sentient toys were once humans transformed into toy creatures by a Devil Fruit power. It seems a majority of those close to the transformed victims not only don't recognize the victim they forget the person even existed.
- In Nobunaga No Chef, the title chef, Ken, has extensive knowledge of high-class cuisine and Japanese military history so he knows what foods he can and can't make, the outcomes of battles, who his boss Oda Nobunaga is and how he (Oda) will die — and that's it. He lost his memory when he "fell" into the past and the only other person who might know ("Ken! You must return to the Heisei era!") is killed. He gets the occasional flashback but these aren't terribly helpful since he doesn't remember who that guy was who taught him military history as a boy and what a buffet is.
- Superman #296-299 had a storyline where Superman finds himself powerless as Clark Kent and spent most of it sticking to one identity while trying not to fall back on the other. In the end, he had come to a realization:
Superman: I tried to decide whether Clark or Superman is more important...and realized that to do away with one would be to kill half of myself—whoever I really am! So even before I got rid of my power problem, I'd decided...meek, mild-mannered Clark Kent will still walk the streets of the city, while up in the sky...the world will still watch and thrill to the sight of—A JOB FOR SUPERMAN!
- While Knights of the Old Republic fanfic adores this trope, the Brotherhood of Shadow fan-made expansion pack cranks it Up to Eleven with virtually every major character abandoning, obliterating, and adopting new identities. A Twi'lek named Channa Mae was found by Jedi Master Solomon, who nicknamed her "Matilda." When the Mandalorian Wars came, Channa Mae abandoned Solomon and the Jedi, as well as the nickname, to fight for Revan's cause. After the war, she abandoned even the Channa Mae identity to become "Shadow," Revan's assassin/aide/secret apprentice. When Revan "died," Shadow found her Force connection severed and became Sera Degana, a crewman on a smuggling vessel. But, then Revan and Solomon come back into her life... Another example is Kobayashi, who was once a Jedi apprentice, and lost his own Force connection after his master was killed, then took on a new identity as a scout and smuggler. Solomon also abandons his identity after being critically wounded and thought dead on Taris. His goal is to kill Revan - and Shadow - to avenge his former Padawan and his niece (who Channa had to kill in self-defense). The Brotherhood of Shadow itself cements it all - they were an elite Sith order who were critical in repelling the Rakatan invasion of their world, seeing themselves as a single unit, not as individuals. When the first Sith Lords betrayed them, the entire Brotherhood was locked in a mind-trap. Over the millennia, they truly did become a single mind - one looking for a host.
- Glory suffers this in Fallout: Equestria - Project Horizons when the Killing Joke (not the comic book, but a virulent, mutated, radioactive strain of Poison Joke) transforms her into a clone of Rainbow Dash. She finds herself losing most of her intelligence as Dash's harebrained adrenaline junkie personality overwrites her own calm, rational, intellectual one. And to make things worse, Rainbow Dash was her civilization's equivalent of Emmanuel Goldstein.
- In Mega Man Defender Of The Human Race, sometimes Mega Man is so busy being Mega Man that he forgets he can be Rock.
- Dark City goes hog-wild with this trope. Every resident in the city (except Dr. Schreber, and even he's not truly spared) is not who they think they are. Every night, The Strangers will go in and mix up a new batch of memories for every person in The City. There is no telling how many years this is going on, and it's highly unlikely that there's any copies of each person's original memories, and thus personality.
- The Hero's refusal of the serial killer identity becomes a major plot point because The City was set up to determine whether memories were the deciding factor. Now that they have proof that they weren't, they can shut it down for good.
- While humans seem to subvert this trope, retaining aspects of their personality even after their memories have been changed, the Strangers seem to play it straight. When Mr. Hand takes on the serial killer memories Murdoch was supposed to have, it really does change him into a monster.
- The 1996 movie adaptation of Casper expanded Casper's backstory, which involved him slowly losing his memories of his former life when he became a ghost. He does have recollections when he finds his old toy room, but it might just be a matter of time until he forgets who he is again. The idea of ghosts losing the identities of their living selves also becomes a tearjerker when Kat's father turns into a ghost and cannot remember who his own daughter was before he was resurrected in the Lazarus machine.
- In the scifi film Eleven, by Makodap, the main character Pete Baxter attempts to leave a future hotel without paying his bill. Before he can leave, a woman called miss Stevens gives him a gift of scotch, upon drinking it and phoning for call girl, Pete is transformed into the woman he ordered, and slowly starts to loose his mind, becomming her mentally.
- This is the crux for much of the drama in Regarding Henry, starring Harrison Ford. In it, the title character survives a gunshot wound to the head, only for the resulting pinched artery to affect his memory. Cue the rest of the movie depicting him coming to terms with not remembering anything about his life before the shot.
- This is a major theme of Dont Look Back, as growing inconsistencies between Jeanne's memories and reality cause her to start question who she really is and how many of her memories are actually real.
- The movie for the album The Wall, shows this symbolically. If you see a group of people wearing masks, such as on the train during "Another Brick In The Wall Part 2", or during the rally in "Run Like Hell", then this is what it means.
Live Action TV
- Death of personality has replaced capital punishment in Babylon 5. A machine wipes the personality and memory of a murderer and replaces them with a new set, letting them live out a life of willing hard community service with an assumed identity without them ever being the wiser. A telepath is present to perform scans before and after, so as to ascertain that the process has worked, but does not carry it out themself.
- The Vorlons and the Shadows leave the galaxy when they are asked their own Armor Piercing Questions and they realize they don't have answers to them anymore.
- The Doctor's ability to regenerate is an interesting twist on this: the many incarnations of the Doctor have entirely different looks and personalities, yet they somehow remain fundamentally the same character.
- Lampshaded heartbreakingly by the Tenth Doctor, who viewed each regeneration as the death of his current self.
- Also explored in the "Human Nature"/"The Family of Blood" two-parter, where the Doctor's Memory Gambit creates a completely new and separate "John Smith" identity with his own personality and memories, who is terrified at the idea that restoring the Doctor's memories will kill him. Seems like a reasonable reaction to realizing your entire life is a lie and you were invented on a whim by an unstoppable alien mastermind, frankly.
- In the episode "A Christmas Carol", the antagonist has a MacGuffin device with isomorphic controls which only he can operate, and he is unwilling to help save a crashing space ship. The Doctor meddles with his past, changing his memories and character in the process. When he finally succeeds in changing him to someone willing to help, the controls no longer respond because they no longer recognize him as the same person.
- Also seen in what happens to victims of Cyber-conversion. The memories remain, but what this form (called "Human.2" by the Cybermen) lacks is emotions and a true understanding of what happened to them. It has been seen that those Cybermen who are made to realize the truth generally blow up, as they cannot live in that form.
- In a different vein, the TV series Nowhere Man had as its title character a man whose existence has been erased.
- Joss Whedon has begun to explore the effects of complete mental reprogramming in Dollhouse.
- It also happened on Angel when he wiped Connor's mind and gave him different memories. And apparently, gave some fairly specific instructions on what he wanted his new personality to be like.
- An unintentional (... probably) side effect of the Wraith retrovirus in Stargate Atlantis, at least until one of its more notable victims got his hands on it.
- Done in a rather heavy-handed way on Heroes, in the episode "I Am Sylar".
- More is sure to come in volume 5 once "Nathan" cottons on to the truth.
- Criminal Minds dealt with this in "Tabula Rasa": a serial killer awakens from a three-year coma with total retrograde amnesia. The BAU tried to prove him guilty, but a couple of them raise the point that even if they did prove that the man named Brian Matlof was responsible for the murderers, the Brian Matlof sitting in court could be argued to be a different person. Eventually his memories return, and he escapes, returning to one of the bodies to verify his own memories. When the BAU arrive, he threatens to kill himself, believing that he'll get the death penalty anyway, but Hotch says "if you really believe that you're a different person, prove it. Do the right thing", and Matlof decides to plead guilty instead, avoiding the death penalty.
- In Battlestar Galactica (Reimagined) a number of characters suffer identity crises of various types. The Eights get the worst of this: Boomer almost shoots herself because she 'doesn't know who she is anymore'. She and other 'sleeper' cylons have serious identity crises when they discover that they've been cylons the entire time and that all their memories are falsehoods implanted by Cavil or other cylons.
- A related philosophical question is called "The Ship of Theseus": if each plank in the ship is replaced when it starts to rot, and over time one-by-one every single plank is replaced, at what point (if ever) does it stop being the same ship?
- The Ship of Theseus is also known as George Washington's axe (my grandpa replaced the handle, and my father replaced the head).
- There's a Kerryman joke to that effect: a Kerryman boasts that he's had the same axe for the past fifty years - with the handle and head replaced, respectively, five and eight times.
- Specifically, this trope is about the philosophical problem of personal identity. The general notion is that people stay more or less the same throughout their lives, despite changes to their bodies (if these changes do not drastically change the way the body functions). Just what makes several iterations the same person, is central to the debate. The debate itself is notorious for the heavy use of science-fiction examples, such as:
- Teletransportation: if a teleporter dematerialises you and reconstructs you elsewhere, are the iterations the same person? What if the original is never deconstructed, but a duplicate is made?
- Brain and/or mind-transplants: are you still the same person when you have a completely different body?
- Not so much Philosophy but a real life example that I personally believe answers this question somewhat, in "Peopleware" a book about managing programmers a case study was made of "the black team". The black team had a strong cultural identity that survived after every original member had left. The second generation picked it up from the first, the third picked it up from the second.
- Hey, this was used in The Fifth Elephant with the hereditary axe. Sometimes the handle needs to be replaced, sometimes the head, but it's still the hereditary axe.
- And what if the old head, rather than being thrown out entirely, is reforged into a new head for a new axe? Is that also the hereditary axe?
- Keep in mind this also applies to people. Your entire body is completely replaced once per decade, give or take.
- In addition, our particles are in constant flux. On the lowest observable levels, we aren't the same from one nanosecond to the next.
- Even with the cells that stick around for a few years, the atoms that make up the cell won't be the same from one month to the next. Your entire body is only a channel for matter, all the atoms in your body won't be there within a few months, and as creepy as it is a lot of them will probably be in other peoples bodies and vice versa.
- But keep in mind (no pun intended) that essentially going down to the molecular level all that makes you "you" is your DNA, the genetic blueprints and instructions stored within your cells. Individual atoms are not any different from each other, able to give perfect transfers of kinetic energy during collisions. The only means of differentiation at that level is the way the atoms assemble; that is what makes you "you".
- This isn't quite the case - epigenetics is a massive field of things necessary for DNA alone to create a functional cell, and environmental effects always affect the organism during development. Case in point, picture how a fetus develops differently if the mother drinks heavily during pregnancy. Or if she's undernourished, lacks critical vitamins, or any of the other horrible things that can happen to you long after sperm and egg meet.
- In The Wonderful Wizard of Oz the Tin Woodman got his body replaced one piece at a time, including his head, when his enchanted axe cut it off. But since it was one piece at a time and not all at once, "he" is still Nick Chopper (his name pre-tinning) rather than some entirely new being.
- On the other hand, in The Tin Woodman of Oz, the Tin Woodman meets his former head in a cupboard of the smith who made his tin body, and they have a not-very-interesting (or friendly) conversation. Who is the real Nick Chopper?
- In a gross oversimplification hindered by linguistic equivocations, traditions descended from the Vedas such as Buddhism, Taoism, and Hinduism solve this problem by seeing self not as a permanent thing, but more like a moving wave. How can it be the same wave when no molecule of water is a part of it for long? Simple: the wave is organized motion through time. Self is usually described as unreal, but best viewed as action-through-time. A deeper discussion of this would probably be way past the scope of this page.
- Douglas Adams struggled with this when he visited China during Last Chance to See and notes that an important historical building looks far too new. A local explains that the original burnt down, and was rebuilt from all new materials (and not for the first time). Adams asks how it's even the same building, and is told "It's always the same building" as if the question is crazy. He concludes that someone is missing the point, but that it may well be him.
- A crucial part of The Hero's Journey, frequently manifested in the Belly of the Whale.
- Truth in Television: Lobotomies, a surgical procedure where the frontal lobes are removed (or a few vital areas are sliced), essentially destroying the personality of the individual concerned.
- Phineas Gage
- It seems to depend. During the period where lobotomies were a popular treatment for troubled teens, a "doctor" developed the non-skull-breaking technique of sticking a thin rod through the eye socket, swerving around the eyeball, and stirring it around in the frontal lobe. There's a picture of said doctor merrily doing this to two patients at once. Results varied wildly. Some people hardly seemed affected at all, aside from being very pissed about it. Brains are complicated things that can form new connections to make up for some damage. That's how despite losing brain cells every year, humans don't peak in intelligence at twenty-five and get stupider from that point on. Brain cells can take up a lot of slack.
- Lobotomies, in their original form, certainly have a well-deserved reputation for being dangerous and damaging the subject's personality, but modern developments (such as the cingulotomy) are apparently far less so, and can be far more successful in alleviating mental disorders without disrupting an individual's personality. The book Opening Skinner's Box by Lauren Slater devoted a chapter to psychosurgery where she pointed out that cingulotomy surgery tends to be much more effective than conventional psychopharmocological drugs in treating long-lasting mental disorders, but the former is still stigmatized as highly unsafe and invasive, so surgery is rarely carried out. In the US, an individual with severe mental disabilities must demonstrate that a large variety of drugs have had no effect in alleviating their suffering before a cingulotomy will be considered.
- There's also The Myth of Fingerprints, where fingerprints from say 8 years ago are identified as Alice, but since the entire body regenerates it's not really the same person after enough time passes. Even brain & nerve cells do replace themselves, but they do it so slowly that the effect is negligible, which is why it took so long for scientists to notice.
- That logic was played with by Terry Pratchett in one of the Discworld books. Sgt. Colon, in an attempt to look somewhat more intelligent, makes the 7 years comment. Nobby then raises the tattoo question. Fred's response is that those cells came from other people's tattoos, which might qualify as fridge squicknote . Colon, at least, is excused for ignorance.
- Query: if the nerves connecting the two lobes of the brain are cut, what happens to the self, or the sense of self? What happens to "I"?
- Very little, as it turns out. Corpus callosotomies are rarely but regularly performed to alleviate severe epilepsy. Speech and memory are affected some, but the sense of self is usually entirely intact.
- In the Big Finish Doctor Who episode "The Natural History Of Fear", the setting is a George Orwell style dystopia. The state Editor, who's in charge of "revision", has the Doctor's voice, but he acts like a completely different person. When it's revealed that "revision" is pretty much an irreversible lobotomy followed by a brand new personality implant, we get some idea of what may have happened to him and his companions... to add to the Mind Screw, it's the only Big Finish episode that has only a cast list instead of a proper credits list.
- According to reincarnation doctrine, deceased souls are brought back to life in another body... but that doesn't mean they come back as a whole person or animal with any memories intact.
- The Dalai Lama is found each time by placing a young child in front of a wide selection of toys; he'll play with the same ones every time. So something is kept intact (then again, the Lama is said to be able to willingly decide if he reincarnates or not, so there's a belief that he has more control over this than a more less enlightened person).
- In Dungeons & Dragons, getting bitten by an Ophidian (snake-like creatures commonly found as slaves of the evil serpentine Yuan-ti) results in a not-so-pretty transformation process. After two weeks, the victim fully transforms into another Ophidian, with no memory of its previous existence.
- Similarly, a Mind Flayer larva devours the brain of a host humanoid, and absorbs the host body as part of its own, in a process called ceremorphosis. The newborn creature has no memory of its host's existence. However, mind flayers scare other mind flayers with stories of the Adversary, a mind flayer who retained its host's personality and, in revenge, dedicated itself to destroying mind flayer society from the inside.
- Also true of some varieties of slaad (embodiments of Chaotic Neutral), of bodaks (featureless beings similar to but distinct from doppelgangers), and of many varieties of undead. This seems to be associated with magical creatures that are either evil, or so chaotic as to be completely beyond conventional morality.
- When dealing with undead, it tends to vary depending on the type. A mindless undead like a zombie is just an empty body, and with the proper magic a person could be resurrected with a new body that exists alongside the zombie, since the soul left the body upon death. A vampire on the other hand must be slain to bring back the person - the vampire has the memories and personality of the original, but is twisted into evil and the person brought back will be the original again.
- The New World of Darkness uses this often as an example of what happens when your Karma Meter bottoms out.
- Vampire: The Requiem — hit Humanity 0 and your Beast takes over, reducing you to a predatory draugr that cares only about feeding.
- Werewolf: The Forsaken — hit Harmony 0 and the human half of your spirit decays entirely as some other type of spirit fills the gap, turning you into a zi'ir.
- Changeling: The Lost — hit Clarity 0 and you disappear into anything from constant hallucination to utter catatonia and if you do it when you're Wyrd 10, you become one of the Gentry.
- Geist The Sin Eaters — hit Synergy 0 and your soul departs entirely, leaving your geist to use your body as a flesh puppet to fulfill its strange desires.
- Mummy: The Curse plays around with it; whereas the default for most supernaturals is Morality 7, most Arisen rise from their slumbers with Memory 3, meaning they're little more than divine murder machines in service to the Judges. It's only as they remain awake that they start remembering who they were over the years... only to have to face the possibility of forgetting it all again with the inevitable return to the tomb.
- In Nobilis, the lifepath example in Antithesis 1i features a girl who nobody listened to, who found that people would listen if she repeated the sounds made by the local environment. So she kept doing so, until one day, she realised she no longer knew who she was or what she would say - she had become nothing but the voice of Morrowen Hollow. And then the Voice, the pattern of sound, took on a life of its own.
- Unknown Armies features a Sanity Meter with five separate variables. Self represents approaching this trope from one of two ways - either losing yourself in utter cynicism until you'd betray your old ideas ("Getting hardened,") or else taking so many blows to your sense of self you are just a wreck ("failed checks.") In either case, maxing out either end of this meter means there's virtually no "you" left in there.
- In BIONICLE, the plan of the Big Bad Makuta Teridax involved trapping the entire Matoran population of Metru Nui into metal spheres, which, over time, deteriorated their physical bodies and wiped their memories clean. The Turaga elders had to reteach everything to them, however one Matoran, Ahkmou, accidentally ended up with Teridax himself, who proceeded to forge a new, evil identity for him.
- Another example is what happened to the Toa Mata. Due to their malfunctioning canisters, they drifted for such a long time in the ocean that their muscles rotted away (even though the canisters were sealed) and their body parts got jumbled together. When they awoke and put themselves back together, it took some time for their lost identities to reemerge, however only their leader Tahu got his full memories back eventually.
- In Misfile, Ash is turned into a girl and history is rewritten to reflect that Ash had always been a girl. Even though Ash has a good (apparently better) life, he believes that he can't give in because if he does, it's tantamount to suicide for boy!Ash. Worse, if the misfile is exposed and covered up, he won't have a choice any more. Ash is constantly proving to himself that he's still the Ash he remembers instead of the Ash that the rest of the world remembers.
- In a recent storyline of The Wotch (which generally tends to gloss over this trope), Ivan wrestles with this after he is transformed as Disproportionate Retribution for snooping and trespassing by Miranda West, and eventually comes out for the better by reasserting his goals.
- Depending on how you look at things, Ellen in El Goonish Shive is either Elliot's Opposite-Sex Clone, or a magical curse given human form. She has all of Elliot's memories up to the point when she split off from him, and initially believes herself to be Elliot, then snaps and tries to become a villain (with the emphasis on "tries"), then becomes a Death Seeker, and finally develops her own identity as Elliot's "sister."
- This trope is the reason that Justin refuses to allow himself to be permanently transformed into a girl (he knows that a girl being attracted to guys would earn him less ridicule than being a guy attracted to guys). Even if it would make his life easier, he still identifies as a man.
- In Jack, it's one of the major plot points. The titular anti-hero/villain is undergoing eternal punishment for his sins (which, as it later turns out, include wiping out the entire human race) - but his last wish in life, which was also part of the punishment, was not to remember anything. A major motive in the comic is Jack gradually regaining his memories - and the source of many people wondering, is he still the same person when he remembers everything?
- In TwoKinds, this happens to Trace twice: first when his mind is destroyed, and again when he loses his memories. It's theorized that his nice side is real because that's how he was before lost his mind for the first time.
- In Sinfest
- In Archipelago, when people who knew Blitz before he lost his memory meet him, they all agree that he's completely different from Anthony, the person they knew.
- In Far Out, the central robot starts to realize what he wants to be, though he has no clue who he is, or was.
- Happens in many, many Transformation, Robot, or other such things pictures, stories, comics, and other such things. There's a very good chance that, if transformed into something else, a character will cease to be who they are. Occurs often in the work of Arania, and also in some of the stories of Amhein.
- Also frequently the end result of Age Regression works; after the character is physically age-regressed, they may or may not retain their memories and personality; however even if they do not immediately fall back into childish behaviour patterns, such changes usually happen whether they are preferable or not. This often affects memories as well, such that the process of regression will cause them to forget that they are regressing; it's hard to fight against something that you don't even know is happening to you until it's too late....
- In Arcana Magi, this happens to Alysia. To the point that she believes her new identity IS her real identity, even though she still has some of her real original memories intact.
- A common fate of victims in The Slender Man Mythos.
- In Worm, Taylor suffers mental deterioration from Panacea tampering with her brain that erodes her memories and her sense of self and eventually results in a complete loss of identity.
- Adventure Time has the Ice King, who Was Once a Man, and lost his memory and most of his personality as he lost his humanity to an Artifact of Doom. Its implied he might still be in there somewhere, but buried so deep not even he knows it anymore.
- Spoofed in the Sponge Bob Square Pants episode "Missing Identity", where SpongeBob misplaces his name tag and treats it as Serious Business.
- In the Teen Titans animated series, Fixit tries to "repair" Cyborg by taking away all that made him human and replacing it with fully mechanical parts and a mechanical brain. Cyborg is justifiably freaked out, because, without his humanity, he'd be just a emotionless machine with his memories. Eventually, it is Cyborg's humanity that causes Fixit to remember what he lost.
- Xiaolin Showdown - One of the Shen Gong Wu, The Monkey Staff, turns the user into a being with a similar appearance, strength, agility and balance to a monkey. However, if used too long, the user will believe that he or she is an actual monkey, and his or her human memories will be erased until the staff is taken away.
- Popeye has one short where Olive Oyl invites Popeye over for a good meal; Wimpy, ever the Big Eater, disguises himself as Popeye to get the food himself. Despite the Latex Perfection of the disguise, he still manages to come off as an Oddball Doppelganger, yet Olive is fooled, and Popeye himself suddenly laments the possibility that he is not himself.
- The Mind Manipulation tropes page would count, since it's about messing with people's loyalties and turning them against their friends and families.