History Main / TheseusShipParadox

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[[quoteright:350:https://static.tvtropes.org/pmwiki/pub/images/theseus_0.png]]
[[caption-width-right:350:[-Art by [[https://www.pastille.no/comics/ship-of-theseus pastillustrator]]-]]]

* ''Literature/TheMisfitOfDemonKingAcademy'': Referenced when Anos disintegrates an opponent, then immediately resurrects him, then repeats the cycle to torture him. During a break, Anos makes the guy paranoid and scared by asking if he thinks he is his original self or a copy.
* This gets addressed in ''Franchise/OnePiece'' when the Straw Hats are hoping to repair their ship, the Going Merry. Because the keel (essentially the backbone of any ship) is severely cracked, the ship is declared irreparable. When Luffy suggests they just build a "new Going Merry", it's pointed out that even if the shipwrights built a new ship precisely like the present Going Merry and built to the Merry's specifications, it actually wouldn't end up being precisely the same, because of inevitable variations in the construction material. It wouldn't be the same ship and the crew would definitely feel that it wasn't the same ship, even if it was built the exact same way, making it pointless to build the same ship from scratch rather than just building or buying a new one.

* In the Stanley Holloway monologue ''The Beefeater'' when visiting the Tower of London they are told that the axe on display "has 'ad a new handle, and perhaps a new 'ead, but it's the old, original axe".

-->'''Vision:''' I grant your query, but regardless of how many of my--your--artificial limbs and organs may have been exchanged, your intangibles--your ''brain patterns''--will forever remain based on an ex-Avenger named Simon Williams.\\

* ''ComicBook/GuardiansOfTheGalaxy2020:'' Discussed between Drax and his daughter Moondragon in issue 3, regarding Drax, who thanks to various shenanigans, deaths, resurrections and messes with the Soul Stone is unsure whether he's really the same Drax or Arthur Douglas, and is unsure whether he owes anything to them.

* ''ComicBook/TheUltimates2015:'' During a chat between the newly redefined Galactus and [[RealityWarper the Molecule Man]], the latter brings up the recent [[ComicBook/SecretWars2015 destruction and rebirth of the multiverse]]. Owen asks whether, given that so many and so much transitioned through, whether the old omniverse ever died at all, and what that means (especially in regards to Galactus' role in all of it.)
-->''That omniverse died. But a lot of the lives in it carried on to the new one. Same broom--new handle. So. Did the omniverse die? Are we the eighth cosmos, or still the seventh?''
* Brought up in the AU series ''ComicBook/XMenForever'' regarding [[spoiler:Storm being split into three different figures; "Perfect Storm" is essentially a clone created by the Consortium, while the original Storm's body is regressed to an amnesiac teenager and her mind and essence is converted to an energy form that is provided with an artificial body by Tony Stark, the energy form eventually merging with the teen Storm to restore them both to adulthood]].

* ''FanFic/{{Eugenesis}}'': Towards the end, [[spoiler:Nightbeat]] dies but leaves behind a device and blueprint that will allow the others to rebuild him. Afterwards, he reflects on this trope; he’s exactly like he was down to the very second that he died, but he’s been built from the ground up and doesn’t have one bit of his original body in him. So does that make him a clone rather than the original [[spoiler:Nightbeat]]?
* In ''Fanfic/ForgedDestiny,'' [[TheBlacksmith Jaune]] creates [[NamedWeapons Crocea Mors]] to the exact same specifications each time he crafts it. The original steel sword was shattered in the battle with [[spoiler:Watts]] but Jaune gathered some of the shards and reforged the blade using Vacuan Silver. Jaune perfectly recreates the blade again when he gets hold of some enchanted metal. When that blade is similarly broken, he makes a new sword from scratch but still with the same shape, weight, balance, and reach as each of the previous ones. Each of these swords is still Crocea Mors[[spoiler: according to Jaune's second Passive, Blade Bond, which increases damage dealt in proportion to the length of time the same sword has been wielded.]]

* ''Film/JohnDiesAtTheEnd'': The film opens with David beheading a body with an axe. However, the handle breaks and he gets the handle replaced. Later, he chips the head killing a centipede... thing. Eventually, the guy he beheaded comes BackFromTheDead, and the reanimated corpse points to the axe and says, "That's the axe that slayed me," to which David asks the audience, "Is he right?" The plot point from the original book that this question foreshadows was removed from the film.

* ''Film/TheWorldsEnd'': [[TheAllegedCar The Beast]] has had every meaningful part replaced, but looks the same and runs about as junkily as it did in the '90s. [[spoiler:This foreshadows what the Network has done to Newton Haven: it claimed the place was "better" and only [[KillAndReplace killed and replaced]] who it needed to, but over the last two decades only three of its human residents remained and most of the local culture has been erased. All this leads to Gary, Andy, and Steven [[ArmorPiercingQuestion asking the Network how it can consider it the same town]].]]
* ''Film/AvengersAgeOfUltron'': Before the third act, Tony and Bruce download JARVIS into a vibranium synthezoid body that Ultron intended to use as his ultimate form, and Thor brings him to life with lightning from Mjolnir. The result is a being they take to calling [[ComicBook/TheVision "Vision"]]. Vision has the physical form of [[Creator/PaulBettany the actor]] who voiced JARVIS, and is primarily composed of JARVIS's matrices, but he insists he's not JARVIS. Ultimately, ''Film/AvengersInfinityWar'' establishes that he's comprised of the minds of Tony, Bruce, Ultron, JARVIS, and the Mind Stone.

* ''[[Literature/TheAlcatrazSeries Alcatraz vs. The Scrivener's Bones]]:'' Discusses this trope.

* ''Literature/TheBelgariad''. Alluded to in the ''Malloreon'' series. Poledra tells Beldin that she's surprised he hasn't changed his tunic during the thousands of years since she last saw him. Beldin says that he patches it, and replaces the patches as they wear out, to the point that the original tunic "is only a memory".
* Towards the end of ''Literature/BicentennialMan'', Andrew Martin starts a FrivolousLawsuit over how much of a human can be replaced with robot-like parts before they're no longer human to get a precedent on the opposite - how much of himself he needs to replace with human-like parts to be considered human. [[spoiler:The ruling ultimately decrees that the one part that matters is the one thing he can't swap out - his brain.]]
* ''Literature/CardForceInfection:'' Fletcher has used "the same" deck since he first got into Card Force shortly after his parents divorced, though numerous little changes over the years mean that it doesn't actually have any of the same cards it had then. [[spoiler:Losing it to Maxwell]] is directly compared to "sinking the Ship of Theseus".
* ''Literature/TheCosmere:'' All things--including objects--have a physical, cognitive, and spiritual element. The cognitive element involves how the object is viewed, and how it views itself. A ship is just a few awkward pieces of wood, except people think of it as a ship, so eventually it begins thinking of itself as a ship as well. This provides a solution to the paradox: As long as the repairs and replacements are done slowly enough that people still think of the ship as the same ship, the ship itself will agree.

--> Most of the harps were old. It wasn’t as if they wore out. Sometimes they needed a new frame, or a neck, or new strings — but the ''harp'' went on.

* ''Literature/JohnDiesAtTheEnd'': The book begins by exploring this question. David beheads a body, but the handle breaks on the last swing. He replaces it. He later chips the head on another [[WeirdnessMagnet supernatural creature]] and replaces it. When the guy he beheaded comes BackFromTheDead, the reanimated corpse points to the axe and says, "That's the same axe that beheaded me," to which David asks the reader "is he right?" This question foreshadows the question of [[spoiler:whether "monster Dave" can be considered the same person as the original human Dave that he unwittingly replaced]].

* The English ''Little Red Engine'' picture book series about a [[SentientVehicle sentient locomotive]] includes a title ''The Little Red Engine Goes to be Mended'', in which the author seems to be deliberately exploring this trope. A trip to India has caused the Little Red Engine to be covered in rust after being left outside during the rainy season. It is loaded onto a ship to England and is taken to be repaired, but is found to be in such a bad state as to make it necessary to completely strip her down. While waiting to be taken apart, another engine tells the Little Red Engine: "As long as they still have a drawing of you with your number and your name you’ll be all right. In the drawing you are seen as a whole. The whole is more important than the parts, so it does not matter if they take away the bits. And your name and your number tell people who you are. While they still have those you retain your identity - you are still the Little Red Engine - you are still yourself." The engine is then taken completely apart and the parts are taken away. We are told explicitly that its original name and number have been taken to the brass shop for actual restoration. One major part, the boiler, is mentioned to have been taken away to the boiler shop, suggesting that an attempt may have been made to restore it. Also, when Sam Trigger, its driver, comes to see how things are progressing, he is told that "the smaller parts" are in a water and caustic and soda bath to remove the rust and oil; these will be reused ''if'' they are not too badly damaged, in which case they will be sent for scrap. Sam then sees various parts being built more or less from scratch.[[note]]The author specifically mentions a new frame (a ''major'' component), the steel outer shell of the firebox, and ''possibly'' the copper inner shell, brake blocks, a connecting rod, a drag hook, some or all components of a wheel pair, new stays, studs, pins and bolts, and oil trimmings[[/note]] Then all the engine's parts are brought together and reassembled; the Little Red Engine, now shown as sentient again, is repainted. Sam gets her going, and drives her home. The book presents something of a mindscrew; whether any substantial portion of the original components has been re-used, or whether all but perhaps a symbolic handful of parts of the Little Red Engine were built anew, is an open question. Judge for yourself [[https://lesliewoodartwork.com/the-little-red-engine-goes-to-be-mended here]].
* Oz stories
** An early example is the Tin Woodman from ''Literature/TheWonderfulWizardOfOz''. He pissed off a witch who enchanted his ax so that it would cut off pieces of him, and he went to a tinsmith to replace the missing parts. Eventually he was made entirely out of tin - but since it was a gradual process, he's still human Nick Chopper and not a new person. Even more paradoxically, however, and with more than a bit of FridgeHorror, the tinsmith kept the old head in a closet, where, due to the no-death nature of Oz, [[AndIMustScream it remained sentient]], desiring nothing to do with the Tin Man when he returned to retrieve it. His beloved eventually went on to marry a person assembled out of all the cut-off pieces.
** In ''[[Literature/LandOfOz The Road to Oz]]'', Jack Pumpkinhead is shown with a garden of new pumpkins grown to replace his head whenever the current pumpkin spoils. He claims that since the head is the smaller part of his body, he remains the same person. Also, in ''The Marvelous Land of Oz,'' one of his legs is used to replace the broken leg of Sawhorse and is later replaced in turn by a table leg. Neither seems affected by the change.
* ''Literature/ParallelLives:'' The TropeMaker and TropeCodifier. The concept is described in a famous paragraph in his ''Life of Theseus'':

* Played with in the ''Literature/{{Shannara}}'' books, when Morgan Leah says that every part of the ancestral sword of the Kings of Leah has been replaced multiple times--except for the actual blade, which is over three hundred years old and is still in perfect condition. This is what makes him believe that the story of Alannon enchanting the sword three hundred years previous is true (Which it is).
* ''{{Siddhartha}}:'' Touched on towards the end. One of the keys to the titular character's (eventual) enlightenment is coming to understand that "you cannot step into the same river twice" (because the water which makes it up has kept flowing downstream)
* ''Literature/SoLongAndThanksForAllTheFish:'' Invoked with Marvin the Paranoid Android. Over the course of four books, the hapless robot has been thrown back and forth through time then left to fend for himself so frequently he is now 37 times older than the universe, and almost[[note]]Except the pain-raddled diodes down his left side[[/note]] every part of him has been replaced at least 50 times.
* Hinted at in the ''Franchise/StarWars'' ''Literature/LegacyOfTheForce'' series. While flying ''Slave I'' in his introduction, Boba Fett muses that the only part of the ship that remains from his father's days of piloting it was the pilot's chair.
* ''Literature/TomorrowTheWorld:'' Because the Austro-Hungarian navy is starved of funds thanks to weak commanders and political wrangling, they use 'official reconstruction' to build a new ship under the guise of repairing an old one. The sailing ship the protagonist is on has been broken up and rebuilt twice, yet keeps the same name to maintain the subterfuge. Naturally this trope is lampshaded.
* ''Literature/AYearAndADayInOldTheradane'' a group of thieves is tasked with stealing a ''city street'' that is a PlaceOfPower. Their solution falls on one side of this trope: [[spoiler:Over the course of a few days, they steal and replace all of the cobblestones. When they're done, the street is still there, but all of the parts that made it up originally are gone, which destroys the location's magical power]].

* ''Series/BlackLightning'': [[spoiler: In season 4, Jen's powers become unstable, causing her to explode. She reforms in episode 6 (which is appropriately named "Theseus's Ship") with a new physical appearance. Gambi states that for all intents and purposes, she is still Jen but her father has issues adjusting to the change. However, this is subverted when it is revealed that Jen has actually been replaced by an entity from the ionosphere. The real Jen returns to retake her place.]]
* ''Series/{{Cheers}}:'' PlayedForLaughs when a con artist tries to sell "George Washington's Axe," but then has to explain that all the parts have been replaced over the centuries.
* ''Series/CobraKai'' ended up with such a case in the third season. Johnny's sensei Kreese didn't just swipe the dojo behind his back; he effectively replaced all of Johnny's students -- a RagtagBunchOfMisfits with no goal other than to be able to fight back against a bullying epidemic -- with the very types that were at the heart of their core issue.
* ''Series/DoctorWho:'' {{Discussed|Trope}} and played straight in the episode "[[Recap/DoctorWhoS34E1DeepBreath Deep Breath]]". The antagonist of the episode is harvesting human organs to be able to pilot the ship, but in doing so, he has replaced most of the ship, and of himself. The Doctor lampshades this by saying "If you have a broom, you replace the handle, and then you replace the brush, and do it over and over, is it still the same broom?" The subtext of the conversation concerns the Doctor themselves, who periodically [[TheNthDoctor regenerates]], taking on a new appearance and personality. It's been said that the process replaces every cell in their body, yet they remain fundamentally the same person. During the episode in question, the Twelfth Doctor was newly regenerated and uncertain of his true identity.
** PlayedForDrama in the moment immediately succeeding this speech. The Doctor holds up a metal platter to have the antagonist look at himself on the reflective surface only for the camera to cut to behind the Doctor, showing that the other side of the platter is just as reflective and the Doctor may as well have been talking to himself.
** Unlike the previous three Doctors, identity was a major theme of this Doctor's arc, centering largely around the Theseus' Ship Paradox.
* ''Series/{{Gotham}}:'' PlayedForHorror when the Dollmaker [[YouHaveFailedMe punished one of his subordinates]] by subjecting him to the BodyHorror of replacing most of his body parts with incompatible pieces.
--> '''Dollmaker''': When do you stop being you and become something new?
* ''Series/OnlyFoolsAndHorses:'' The best-known example, where Trigger, one of the characters, is given a medal for owning the same broom for 20 years, although it has had 17 new heads and 14 new handles. When asked how can it be the same broom, Trigger holds up a picture of himself and his broom and says, "Well, here's a picture of it, what more proof do you need?" As a result, the paradox is commonly known in the UK as the "Trigger's Broom Paradox".
* The same joke appears in Creator/DavidJason's previous sitcom ''Series/OpenAllHours'':
-->'''Granville''': We need a new brush.\\
'''Arkwright''': Nonsense! That's a marvelous old brush, that! I've had that for fourteen years. It's only had two new heads and three new handles.
* ''Series/RobotWars''

* ''Franchise/StarTrek'' from the beginning has begged this question ever since it was described how the transporters work. The transporter's function on the show was to be a magic elevator that took the away team to the planet without requiring the director to film a shuttle landing over and over again. The transporters work by dissolving the away team member and assembling a copy of them on the planet below, which makes you wonder if the same consciousness is moved also. Further questions are begged when you consider that in an episode of ''Series/StarTrekTheNextGeneration'', a glitch in the transporter created a copy of William Riker who was marooned on the space station he was transported from, with tests affirming that both Rikers should be considered to be the 'real' one as nobody could determine a difference beyond the fact that one had been trapped on another planet for eight years. Yet more questions are begged when one episode features the only POV shot in the entire series of someone going through the transporter and midstream being bitten by the MonsterOfTheWeek which suggests that the experience of being transported has no break in consciousness. There have also been two instances of conversations continuing between beaming subjects mid-beam in the TOS movies; Kirk explaining the "By The Book" subterfuge to Saavik in ''Film/StarTrekIITheWrathOfKhan'', and the badly timed rescue beam-out from Rura Penthe in ''Film/StarTrekVITheUndiscoveredCountry''.
** ''Series/StarTrekDeepSpaceNine:'' Kira's RomanticFalseLead Bareil Antos gets injured and has part of his brain replaced with cybernetics. As more of his brain fails and is replaced, the less he's him. Eventually he's mostly cybernetics, and rather than continue the process Kira allows him to die.

*** Out of universe, the paradox was [[https://trekmovie.com/2020/04/02/star-trek-picard-finale-sparks-philosophical-fan-debate-is-picard-still-picard/ invoked]] by Memory Alpha editors when, in the first season finale of ''Series/StarTrekPicard'': [[spoiler:Jean-Luc Picard’s human body dies of a long-gestating neurodegenerative disease, but Noonien Soong’s son electronically transfers his mind into a “healthy” robotic body resembling the old body, a perfect example of the BodyBackupDrive trope.]] The editors argued over [[spoiler:whether to create a separate article for each body or not, with the franchise’s precedents for either side being evenly matched, before coming to a consensus to leave Picard’s article un-split, with additions where appropriate.]] The [[spoiler:CloneAngst]] actually got brought up in-universe on occasion in the second season, but [[spoiler:Picard’s original corpse becomes the driving MacGuffin behind the plot of the third season.]]
*** In the last 2 episodes of season 3, [[spoiler:the USS ''Enterprise''-D returns, thanks to Geordi having spent over 20 years restoring her after her destruction during ''Film/StarTrekGenerations''. It's likely that parts from a number of decommissioned ''Galaxy''-class ships went into restoring her; the stardrive section was cannibalized wholesale from the U.S.S. ''Syracuse'' since the ''Enterprise'''s original was destroyed by a warp core breach detonation. Now... the parts are all the ''Enterprise''.]]
* Invoked but defied in ''Series/PowerRangersOperationOverdrive'' [[spoiler:after the android Red Ranger Mack is 'killed' in the final battle; Mack's overall body still appears intact, so there should be nothing to stop Hartford (his creator/father) using his body and reactivating a new consciousness, but Hartford makes it clear that anything he recreated that way wouldn't be Mack, but just "something that looked like him".]]
* {{Discussed}} in [[Recap/WandaVisionEpisode9TheSeriesFinale the final episode]] of ''Series/WandaVision'', with an extra twist where the pieces removed from the Ship of Theseus are then used to build a ''second'' ship, which has equal claim to being the Ship of Theseus. [[spoiler:The Westview Vision has the same essential personality and thought process as the original Vision, but physically he's a [[PureMagicBeing magical construct]] that Wanda Maximoff created in her grief. Meanwhile, [[ReforgedIntoAMinion White Vision]] is a BlankSlate who rigidly follows his programming, but he's physically the reanimation of the original Vision's synthezoid corpse. When White Vision reveals to Westview Vision that he has been ordered to "kill the Vision", Westview Vision counters that, as his opponent, he is only a conditional version of Vision. Westview Vision uses the Ship of Theseus parable to explain the situation to White Vision, which causes White Vision's thinking to become [[LogicBomb caught up in the paradox of who is the real Vision.]] However, this exchange introduces a third aspect into the discussion, the concept of memory and experience. So when White Vision accepts Westview Vision's offer to gain full access to the Vision's memories, White Vision undergoes a defined change. His previously cold, white eyes become full of color and warmth as White Vision declares "I am Vision" before flying off. The scene leaves it unclear if White Vision is now a unification of thought, material, and memory raising the question as to whether the Original Vision is still dead in the MCU... or did White Vision who now identifies himself as the true Vision fly off to destroy himself and fulfill his programming?]].
* ''Series/{{Westworld}}'' Dolores Abernathy has been repaired so many times over the years that she's practically brand new, with at least one character noting that she's one of the "older" robots in the park purely on a technicality. This is used to both obscure and foreshadow TheReveal in Season One that [[spoiler:events featuring Dolores are actually taking place decades apart.]]

* Music/NapalmDeath lost all its original members between its formation in 1981 and its first album in 1987. The lineup continued to change during the recording of that album and everyone who played on it has long since left. Bass player Shane Embury joined shortly after to tour that album and is the only member remaining from that lineup. The lineup has been far steadier since the early [=90s=], three out of four members having been in the band since at least 1991.

* In the ''TabletopGame/BattleTech'' novel ''Close Quarters'' this is referred to with an old ''Jenner'' 'Mech which is "one of the first" ever made--except that every single part, down to even the last nut and bolt, has been replaced over the last 600 years two or three times or more!
** This question also dogs the famous ''Yen-Lo-Wang'', a ''Centurion'' that is over a century old by the Dark Age setting. Tracking its modification history, there is ''no'' part of the 3150-era 'Mech which is the same as the original 3028-era 'Mech. The armor, chassis, engine, and myomer musculature have all been exchanged in modifications. The changes made to the engine necessitate a new gyro. The cockpit was swapped several times to accommodate the modifications. The current iteration of the 'Mech has no weapons in common with the original. Theoretically, a very dedicated person could track down the original parts and rebuild a second, 3025-vintage ''Yen-Lo-Wang'' in 3150, as not even the iconic razor talons were kept between upgrades... so the only thing that allows the 'Mech to be called ''Yen-Lo-Wang'' is the family history that is handed down with it.
* ''TabletopGame/DungeonsAndDragons'': There is a race of aberrations called the Tsochar who are colonies of unintelligent worms fused together to form an intelligent larger worm. The individual worms have a limited lifespan but the colonies can live forever by replacing any worms that die so any sufficiently old Tsochar will be composed of none of the worms that originally formed it.
* ''TabletopGame/{{Warhammer 40000}}''; EvilutionaryBiologist Fabius Bile has kept himself alive in the ten millennia since the Horus Heresy through a combination of cloning and [[BodySurf Body Surfing]], due to suffering from an incurable gene cancer called the Blight. The question of whether the current Bile is the real one or not gets bandied around, with Bile ultimately not caring enough to give an answer.

* In ''VideoGame/Fallout4'' and ''VideoGame/Fallout76'' some weapons have bonus effects, which are preserved even if you replace every component of the weapon with a different one, even going so far as to turn a wooden bat metal.

'''Yu:''' ''(smugly)'' I'll let you ponder that one.\\
''(cut to much later; it is now nighttime and Kay still stands in the same spot pondering the implications)''\\
'''Yu:''' ''(waving at him from the Nest)'' KAY, WE NEED TO GO HOME NOW! YOU CAN THINK ABOUT THAT TOMORROW, OKAY?

* ''VideoGame/MegatravellerTheZhodaniConspiracy:'' (Based on the ''TabletopGame/{{Traveller}}'' game), if any of your party members dies you can recruit a replacement at the spaceport, who will carry on in their stead just as good as anyone else. But if all of the original members are dead, the game ends even if everyone else is alive. The recruits just don't have the same commitment to the original quest.
* In ''Videogame/NierAutomata'', the merchant in the Resistance camp has a damaged leg which he is reluctant to replace as it is the last remaining piece of his original body, and he ponders whether he would still be himself without it.
* In ''VideoGame/{{SOMA}}'', main character Simon is [[spoiler:revealed to be a robot with the memories of the original Simon, who had his brain scanned and then died almost a century before the events of the game]] the topic is brought up several times, most notably when [[spoiler:Simon changes into a new diving suit(read: body), only to discover that the process actually involved making a copy of his mind and uploading it, leaving the original body alive.]] The player is left with the choice of abandoning it or ending its suffering.
* In ''VideoGame/YandereSimulator'', Ayano can speak online with [=Selene2005=], who brings up this paradox as an alternative discussion topic instead of their… [[UtopiaJustifiesTheMeans preferred topic]] of discussion.

* Lucy and the protagonist end up having a discussion on this in ''VisualNovel/LucyTheEternitySheWishedFor'' since over time Lucy could end up having her entire body replaced part by part, and even her memories can be deleted or modified. [[spoiler: By the end of the game, Lucy is destroyed completely (even her memory chips are fried and unsalvageable,) and the protagonist spends the next 15 years learning robotics to try and recreate her from scratch with her memories intact. At first, it seems like he only succeeded in creating a mere copy of the original Lucy, until he's finally able to trigger her memories to come back.]]
* One of the many digressions that comes up during ''[[VisualNovel/NineHoursNinePersonsNineDoors Nine Hours, Nine Persons, Nine Doors]]'' involves the Ship of Theseus.

* ''Webcomic/GirlGenius'': Tarvek would be the first to admit that Anevka has been... different since being given a puppet clank body after her "accident." Though the real problem is that [[spoiler:as Anevka slowly sickened inside her life support chamber, her clank body took up more and more of the slack until even the clank failed to notice that Anevka had died — and the clank was becoming increasingly erratic. Tarvek [[http://www.girlgeniusonline.com/comic.php?date=20060913#.WguHCoZrzq4 shut her down for safety's sake as much as anything else]].]]
* ''Webcomic/ExistentialComics'': The [[https://existentialcomics.com/comic/1 first comic]] takes this trope and runs with it. In a hypothetical future, a teleporter is invented and revolutionizes transportation, but a protest movement arises out of people who claim that the machines are actually killing people and replacing them with clones, as their entire atomic makeup is transformed. One of the protestors confronts the inventor of the device in a bar, who argues that the important part is the emergent pattern, not the precise individual atoms, that make up a person, and he admits that while there's an interruption of consciousness, it's comparable to being knocked unconscious or a good night's sleep, and that if the persistent self survives ''that'', then it certainly survives the teleporter. The protestor ''freaks the fuck out'' at the implication that sleep is the equivalent of death for his consciousness, and he spends the rest of the story wrestling with it until he's finally able to come to terms with it.

* ''WebComic/SaturdayMorningBreakfastCereal'' parodies this [[https://www.smbc-comics.com/comic/2014-11-17 here]] by having an alien claim that humans only live about sixteen hours. Sure the body persists for decades, but if life is continuity of consciousness and humans spend eight hours a day ''un''conscious than over those decades 30,000 people or so will inhabit it. The votey reveals he's just messing with her.
* ''Webcomic/SchlockMercenary:'' The first warship seen owned by the [[PrivateMilitaryContractors Tagon's Toughs]] was the ''Dragon''-class cruiser ''Kitsefear''. After her destruction early on in the comics, she was eulogized [[http://www.schlockmercenary.com/2001-03-21 in a footnote]] that mentioned that "her hull had been patched so many times it's hard to say where the original hull sits."

* Something of a theme in ''WebAnimation/GenLOCK'' when it comes to the titular [[BrainUploading gen:LOCK]] technology. One can even see the phrase "Ship of Theseus" pinned to a wall in Dr. Weller's lab. [[spoiler: As it turns out, when the gen:LOCK program first got started, the doctor made a habit of uploading [[TheHero Chase]]'s mind into ''two'' cyberbrains simultaneously, one running a [[HumongousMecha Holon]], and the other a spare copy. After [[TheEmpire the Union]] captured Chase ([[ReforgedIntoAMinion eventually turning him into the Nemesis]]), Dr. Weller uploaded the copy back into Chase's body and kept it a secret. So the question becomes: which mind is the ''real'' Chase? Both? Neither?]]
* [[WebVideo/MatthewSantoro Matt Santoro]] discusses this paradox in his video ''The 10 Most MIND-TWISTING Paradoxes of All Time!''.

* DiscussedTrope in ''AudioPlay/StrayAmi'' - Blank and Andale decide it's different with people.
* There is a ''WebVideo/{{Vsauce}}'' video discussing a variant: Imagine you have the atoms in your body removed one at a time each atom is replaced by an identical one in the exact same place. At what point would you no longer be the same person, if ever?
* ''WebVideo/CampfireStories'': Mike was once soundly chastised by Zach for taking this very approach to alcohol consumption.
-->'''Mike:''' I don't remember the specifics of it, but I remember something along the lines of "If I put alcohol in this cup again, it's still the same cup, so it's just one drink," right? So 'three' drinks in...I was puking quite a lot and screaming "WHY DO PEOPLE DO THIS?" Long story short, Kirk let me stay overnight.\\
'''Zach:''' ''You can't Ship of Theseus a drink, Mike!''

* In the ''WebVideo/TheMonumentMythos'' the decommissioned prison island of Alcatraz is, in reality, a geographical superorganism that acts like a single-celled creature, performing a perverted version of mitosis on a massive scale referred to as "Alcatrazosis" in which the entire island starts to split into identical versions of itself. In the video ALCATRAZATTACK this process was projected to see the superorganism start to absorb the city of San Francisco by the year 2050, but after blasting the island with high doses of radiation the process became accelerated, and by 2003 Alcatraz has spread far enough to reach West Texas. It's never said what this actually meant for the country, although sounding like some sort of cancerous landmass of Alcatraz islands piling up on top of one another, it is instead much more subtle than that, it simply replaced everything in its path with its own materials, leaving it otherwise to look virtually unchanged. In ALCATRAZAPOCALYPSE it's realized that by 2022 Alcatraz had replaced everything in the United States up to the East Coast, and possibly even further, as Leonard Morlin realizes in horror every cell in his body is different to itself only three days prior. Unable to grasp that he has been effectively replaced without his knowledge Morlin suffers an existential breakdown, citing the 'Theseus Ship Paradox' by name to the American People before committing suicide.

* Joked about in an episode of ''WesternAnimation/FamilyGuy.'' Creator/JoanRivers was doing interviews on the red carpet of the Adult Video Awards and said that she was once asked to do a porno but couldn't because, since she's had so much plastic surgery, more than 50% of her body was under 18 years of age.
* {{Invoked}} in the ''WesternAnimation/{{Futurama}}'' episode "[[Recap/FuturamaS7E7TheSixMillionDollarMon The Six Million Dollar Mon]]", in which Hermes continually "upgrades" himself by replacing various organic parts with robotic prostheses. As each human part is removed, Zoidberg salvages it and stitches them back together. After the final organic piece of old!Hermes, the brain, is replaced and reattached to new!Hermes, there are two Hermeses: an organic one with all the parts of the original (plus a whole lot of stitches), and a robotic one controlled by the processor of the psychopathic robot Roberto.
* ''WesternAnimation/GerryAndersonsNewCaptainScarlet'': Both Captain Scarlet and Captain Black are killed and resurrected by the Mysterons. According to Dr. Gold, the revived Scarlet technically isn't Scarlet but isn't a clone either. Scarlet in one episode expresses concern that he isn't human and Captain Black in another episode admits to not really feeling like a Mysteron at times.

* TheVelvetUnderground album ''Squeeze'' involved no original members. Doug Yule was not just the only player who had played on any other Velvet Underground album, but also practically the only person involved, having written all the songs, played and sung almost all the parts and produced the album.

* ''FanFic/{{Eugenesis}}'': Towards the end, [[spoiler:Nightbeat]] dies but leaves behind a device and blueprint that will allow the others to rebuild him. Afterwards, he reflects on this trope; he’s exactly like he was down to the very second that he died, but he’s been built from the ground up and doesn’t have one bit of his original body in him. So does that make him [[CloningBlues a clone]] rather than the original [[spoiler:Nightbeat]]?

*** Out of universe, the paradox was [[https://trekmovie.com/2020/04/02/star-trek-picard-finale-sparks-philosophical-fan-debate-is-picard-still-picard/ invoked]] by Memory Alpha editors when, in the first season finale of ''Series/StarTrekPicard'': [[spoiler:Jean-Luc Picard’s human body dies of a long-gestating neurodegenerative disease, but Noonien Soong’s son electronically transfers his mind into a “healthy” robotic body resembling the old body, a perfect example of the BodyBackupDrive trope.]] The editors argued over [[spoiler:whether to create a separate article for each body or not, with the franchise’s precedents for either side being evenly matched, before coming to a consensus to leave Picard’s article un-split, with additions where appropriate.]] The [[spoiler:CloningBlues]] actually got brought up in-universe on occasion in the second season, but [[spoiler:Picard’s original corpse becomes the driving MacGuffin behind the plot of the third season.]]

*** Out of universe, the paradox was [[https://trekmovie.com/2020/04/02/star-trek-picard-finale-sparks-philosophical-fan-debate-is-picard-still-picard/ invoked]] by [[TheWikiRule Memory Alpha]] editors when, in the first season finale of ''Series/StarTrekPicard'': [[spoiler:Jean-Luc Picard’s human body dies of a long-gestating neurodegenerative disease, but Noonien Soong’s son electronically transfers his mind into a “healthy” robotic body resembling the old body, a perfect example of the BodyBackupDrive trope.]] The editors argued over [[spoiler:whether to create a separate article for each body or not, with the franchise’s precedents for either side being evenly matched, before coming to a consensus to leave Picard’s article un-split, with additions where appropriate.]] The [[spoiler:CloningBlues]] actually got brought up in-universe on occasion in the second season, but [[spoiler:Picard’s original corpse becomes the driving MacGuffin behind the plot of the third season.]]

* Music/NapalmDeath lost all its original members between its formation in 1981 and its first album in 1987. The lineup continued to change during the recording of that album and everyone who played on it has long since left. Bass player Shane Embury joined shortly after to tour that album and is the only member remaining from that lineup. The lineup has been far steadier since the early [=90s=], two out of four members having been in the band since at least 1991.

* Music/NapalmDeath lost all its original members between its formation in 1981 and its first album in 1987. The lineup continued to change during the recording of that album and everyone who played on it has long since left. Bass player Shane Embury joined shortly after to tour that album and is the only member remaining from that lineup. The lineup has been far steadier since the early [=90s=], three out of four members having been in the band since 1991.

* The Music/TheVelvetUnderground album ''Squeeze'' involved no original members. Doug Yule was not just the only player who had played on any other Velvet Underground album, but also practically the only person involved, having written all the songs, played and sung almost all the parts and produced the album.

[[folder:Radio]]
* Creator/TheBBC Radio 4 cryptic connections quiz ''Round Britain Quiz'' had a question based on this in episode 8 of the 2021 series, asking "Why might a Peckham road sweeper's chief tool, tin in the land of Oz, and the vessel of an ancient Greek hero, not be quite what they seem?" The answers are Trigger's broom, the Tin Woodman, and the Ship of Theseus itself.

[[folder:Radio]]
* Creator/TheBBC Radio 4 cryptic connections quiz ''Round Britain Quiz'' had a question based on this in episode 8 of the 2021 series, asking "Why might a Peckham road sweeper's chief tool, tin in the land of Oz, and the vessel of an ancient Greek hero, not be quite what they seem?" The answers are Trigger's broom, the Tin Woodman, and the Ship of Theseus itself.
[[/folder]]

The Ship of Theseus is a classic philosophical thought experiment about the nature of identity. Is an object simply the sum of the specific parts that compose it? And if those parts are gradually replaced, is it still the same object?

The classic story goes as follows: Theseus sails the world on his famous ship, but as the pieces of the ship begin to wear down, he replaces them. By the time his voyage is finished, every single part of the ship has been replaced. So is the ship at voyage's end still the same ship that first set sail? If yes, what would have to have to happen for the ship to stop being considered the original? If no, at what point did the ship stop being the original?

* One way to look at this problem from a computer science perspective is to look at the difference between [[https://en.wikipedia.org/wiki/Evaluation_strategy call-by-value and call-by-reference.]] Call-by-value passes in data from a location in the computer's memory, usually by copying it to a new location temporarily. Call-by-reference passes in the location itself, which will probably work the same way unless the data in that location changes later on. So how do you tell if two variables are "the same?" Depends on whether the data or the location is important, and there are cases for both. Some languages, like Javascript, even have separate "equality" (==) and "identity" (===) operators just for this purpose.

--> '''Dollmaker''': How much of you can be replaced before you're not you anymore?

* In [[Recap/WandaVisionEpisode9TheSeriesFinale the final episode]] of ''Series/WandaVision''. [[spoiler:The Westview Vision has the same essential personality and thought process as the original Vision, but physically he's a [[PureMagicBeing magical construct]] that Wanda Maximoff created in her grief. Meanwhile, [[ReforgedIntoAMinion White Vision]] is a BlankSlate who rigidly follows his programming, but he's physically the reanimation of the original Vision's synthezoid corpse. When White Vision reveals to Westview Vision that he has been ordered to "kill the Vision", Westview Vision counters that, as his opponent, he is only a conditional version of Vision leading to a namechecked discussion of this trope which causes White Vision's thinking to become [[LogicBomb caught up in the paradox of who is the real Vision.]] However, this exchange introduces a third aspect into the discussion, the concept of memory and experience. So when White Vision accepts Westview Vision's offer to gain full access to the Vision's memories, White Vision undergoes a defined change. His previously cold, white eyes become full of color and warmth as White Vision declares "I am Vision" before flying off. The scene leaves it unclear if White Vision is now a unification of thought, material, and memory raising the question as to whether the Original Vision is still dead in the MCU... or did White Vision who now identifies himself as the true Vision fly off to destroy himself and fulfill his programming?]].

* Most guns avert this with a "receiver" [[note]] Essentially the box that holds everything together[[/note]] being the legal part of the gun. If this is destroyed, the gun is ''usually'' considered destroyed too. However, the famous M60 machine gun has unusually unreliable receiver due to it being welded together out of strips of metal. Thus the US military considers the receiver a replaceable part, which means that ''all'' parts of the M60 are replaceable parts.

* ''Series/{{Gotham}}'' PlayedForHorror when the Dollmaker [[YouHaveFailedMe punished one of his subordinates]] by subjecting him to the BodyHorror of replacing most of his body parts with incompatible pieces.

* ''Series/{{Cheers}}:'' Played for laughs when a con artist tries to sell "George Washington's Axe," but then has to explain that all the parts have been replaced over the centuries.

* ''Series/{{Gotham}}'' Played for horror when the Dollmaker [[YouHaveFailedMe punished one of his subordinates]] by subjecting him to the BodyHorror of replacing most of his body parts with incompatible pieces.

* Some civilizations and empires run into this. A dramatic example is the Roman/ Byzantine Empire. As the Roman Empire fell into decline, it was decided to split the empire into a western and eastern half. The western half, containing Rome itself, soon fell but the eastern half, centered in [[PleaseSelectNewCityName Byzantium/ Constantinople/ Istanbul]], lived on. It even managed to briefly reconquer Rome in an attempt to revive a united Empire. However, most of the Eastern Roman Empire's/ Byzantine's thousand year independent existence it did not control Rome or any of the Roman Republic's original territory. Speaking of the Roman Republic simply transitioned into the Roman Empire and was never formally declared defunct. But at the end, the Byzantines claimed to be Rome without speaking Latin, practicing the classical religion, controlling Rome, or having a senate. When they were conquered, the subsequent Empire, known to history as the Ottomans, also claimed to be Rome.[[note]]Though this claim was deemphasized, if never formally dropped, as time went on. [[/note]] Then you have the various claimants to Roman succession, like the Holy Roman Empire. The Roman Republic and Empire and now both universally considered to be gone, but when is a tricky question.

** Out of universe, the paradox was [[https://trekmovie.com/2020/04/02/star-trek-picard-finale-sparks-philosophical-fan-debate-is-picard-still-picard/ invoked]] by [[TheWikiRule Memory Alpha]] editors when, in the first season finale of ''Series/StarTrekPicard'':
** [[spoiler:Jean-Luc Picard’s human body dies of a long-gestating neurodegenerative disease, but Noonien Soong’s son electronically transfers his mind into a “healthy” robotic body resembling the old body, a perfect example of the BodyBackupDrive trope.]] The editors argued over [[spoiler:whether to create a separate article for each body or not, with the franchise’s precedents for either side being evenly matched, before coming to a consensus to leave Picard’s article un-split, with additions where appropriate.]] The [[spoiler:CloningBlues]] actually got brought up in-universe on occasion in the second season, but [[spoiler:Picard’s original corpse becomes the driving MacGuffin behind the plot of the third season.]]
** In the last 2 episodes of season 3, [[spoiler:the USS ''Enterprise''-D returns, thanks to Geordi having spent over 20 years restoring her after her destruction during ''Film/StarTrekGenerations''. It's likely that parts from a number of decommissioned ''Galaxy''-class ships went into restoring her; the stardrive section was cannibalized wholesale from the U.S.S. ''Syracuse'' since the ''Enterprise'''s original was destroyed by a warp core breach detonation. Now... the parts are all the ''Enterprise''.]]

** Out of universe, the paradox was [[https://trekmovie.com/2020/04/02/star-trek-picard-finale-sparks-philosophical-fan-debate-is-picard-still-picard/ invoked]] by [[TheWikiRule Memory Alpha]] editors when, in the first season finale of ''Series/StarTrekPicard'', [[spoiler:Jean-Luc Picard’s human body dies of a long-gestating neurodegenerative disease, but Noonien Soong’s son electronically transfers his mind into a “healthy” robotic body resembling the old body, a perfect example of the BodyBackupDrive trope.]] The editors argued over [[spoiler:whether to create a separate article for each body or not, with the franchise’s precedents for either side being evenly matched, before coming to a consensus to leave Picard’s article un-split, with additions where appropriate.]] The [[spoiler:CloningBlues]] actually got brought up in-universe on occasion in the second season, but [[spoiler:Picard’s original corpse becomes the driving MacGuffin behind the plot of the third season.]]

* While most guns avert this with a "receiver" [[note]] Essentially the box that holds everything together[[/note]] being the legal part of the gun. If this is destroyed, the gun is ''usually'' considered destroyed too. However, the famous M60 machine gun has unusually unreliable receiver due to it being welded together out of strips of metal. Thus the US military considers the receiver a replaceable part, which means that ''all'' parts of the M60 are replaceable parts.

* This trope is alluded to by ''WebVideo/CinemaSins'' in their sins video for ''WesternAnimation/{{Cars}}'':

* On the ''LetsPlay/DreamSMP'', as the nation L'Manburg gets trashed time and time again and exchanges one president for another[[note]]With founding president Wilbur being succeeded by [[PresidentEvil Schlatt]] after the Election Arc, and Tubbo being made president by Wilbur after Schlatt's death during the CivilWar that broke out as a result of Schlatt's presidency[[/note]], more and more of it gets replaced until it's borderline unrecognizable. For the time being, it seemed to avert fully being replaced thanks to the L'Mantree, a remnant of L'Manburg from Wilbur's presidency that survived even when everything else was blown up or torn down. [[spoiler:However, when the L'Mantree is burned down by [[BreakTheBeliever Niki]] in the Doomsday War, the L'Manburgians realize that nothing is left of their original nation and that it's no longer worth salvaging its ruins.]]

* ''Franchise/StarTrek'' from the beginning has begged this question ever since it was described how the transporters work. The transporter's function on the show was to be a magic elevator that took the away team to the planet without requiring the director to film a shuttle landing over and over again. The transporters work by dissolving the away team member and assembling a copy of them on the planet below, which makes you wonder if the same consciousness is moved also. Further questions are begged when you consider that in an episode of ''Series/StarTrekTheNextGeneration'', a glitch in the transporter created a copy of William Riker who was marooned on the space station he was transported from, with tests affirming that both Rikers should be considered to be the 'real' one as nobody could determine a difference beyond the fact that one had been trapped on another planet for eight years. Yet more questions are begged when one episode features the only POV shot in the entire series of someone going through the transporter and midstream being bitten by the MonsterOfTheWeek which suggests that the experience of being transported has no break in consciousness. There have also been two instances of conversations continuing between beaming subjects mid-beam in the TOS movies; Kirk explaining the "By The Book" subterfuge to Savvik in ''Film/StarTrekIITheWrathOfKhan'', and the badly timed rescue beam-out from Rura Penthe in ''Film/StarTrekVITheUndiscoveredCountry''.