History Main / UnstoppableForceMeetsImmovableObject

"What happens when an unstoppable force meets an immovable object?" is one of the most famous formulations of a YinYangClash in the Western consciousness. As a result, it's become a StockPhrase for describing any conflict between particularly strong or [[{{Determinator}} particularly stubborn]] individuals.

* {{Discussed}} in Creator/RobertLudlum's book ''The Ambler Warning'' by a Taiwanese presidential candidate during a campaign speech, prior to [[spoiler:being assassinated]]. The main plot is also thematically similar: a man with the intuition to SherlockScan anybody's true self realises almost too late that he's been deceived by a highly-trained [[MethodActing method actress]] as part of the BigBad's plot. But then, he was mostly pre-occupied with unravelling his true identity, after having been [[MindWipe Mind Wiped]] and given a false one.

* In ''The Fountains of Paradise'' by Creator/ArthurCClarke a reporter uses this phrase to describe the conflict between ace engineer Vannevar Morgan, who wants to build a space elevator on a mountain, and the abbot of a Buddhist monastery that has been sitting on top of the mountain for thousands of years.
* In ''Literature/TheGrimnoirChronicles,'' the characters Jake (a 'Heavy' able to [[GravityMaster control gravity]] and alter his density) and Toru (a 'Brute' equipped with SuperStrength) have this dynamic, though the spend most of their time as uneasy allies.

* Used as a riddle in the far-future section in Ian Banks' "Walking on Glass". The actual answer is randomly tossed out in the other narrative. [[spoiler:The unstoppable force stops, the immovable object moves.]]

* ''Series/{{The Defenders|2017}}''. When Danny Rand punches Luke Cage, the result is a KungFuSonicBoom that knocks down everyone in the area, including Luke and Danny.

-->-- '''ComicBook/TheJoker''', ''Film/TheDarkKnight''

* Similarly, a Mensa puzzle book from 1991 uses this riddle as one of its logic puzzles. The answer is [[spoiler:an impossible event. Logically, the existence of one disproves the existence of the other by definition, and therefore the two cannot exist at the same time, therefore such an event will never occur.]]

[[folder:Web Original]]
* There are a number of "All-or-Nothing" abilities in ''Literature/{{Worm}}'' that are absolute and flat-out break the laws of physics. For example, the Siberian is utterly invulnerable and [[TheJuggernaut cannot be impeded by any obstacle]], while Clockblocker can freeze objects in time, rendering them completely immovable and impervious to any force. When Clockblocker attempts to use frozen wires to impede the Siberian, the collision is referenced by this trope, and results in [[spoiler:both powers being canceled out, with the frozen objects reverting to normal and the Siberian vanishing, as she is actually [[FightingAShadow a mental projection]].]]
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* ''WesternAnimation/BatmanTheBraveAndTheBold'' episode "Emperor Joker!" has [[ImYourBiggestFan Batmite]] describe Batman's relationship with ComicBook/TheJoker as such. Likely in reference to ''Film/TheDarkKnight'' quoted above.
* ''WesternAnimation/{{Invincible|2021}}'': In episode 6, Cecil remarks how this would play out when Nolan offers to interrogate [=DarkBlood=] over the murder of the Guardians, Cecil prefers to keep the investigation "in-house" even though he admits the sight would be fascinating to watch. [[spoiler:Given he had already sent [=DarkBlood=] back to Hell to keep him from provoking Nolan, chances are it would've happened earlier]].

* ''WesternAnimation/TheSimpsons'': Used on [[Recap/TheSimpsonsS8E3TheHomerTheyFall "The Homer They Fall"]] to describe the boxing bout between Homer (who has been discovered [[MadeOfIron to have a reinforced brain case and is theoretically knockout-proof]]) and returning heavyweight champion Drederick Tatum. Ultimately, this trope is defied -- Tatum is capable of punching so hard that Homer is on the verge of being knocked out (or even getting pummeled to death) ''[[EpicFail within ten seconds of the first round starting]]''.

* In a more metaphorical sense in ''WebComic/AskFriskAndCompany'', [[spoiler:Chara]] believes they can convince Frisk that [[spoiler:the world is irredeemable to get them on their side]], and Frisk believes they can turn it around and do the opposite. Flowey notes that both of them are "[[TheDeterminator pretty stubborn]]," and concludes "So who knows?" In the end, it'll just depend on who comes out more DETERMINED.
* ''Webcomic/{{Freefall}}'': Bill Raibert notes that "[[http://freefall.purrsia.com/ff2800/fc02713.htm That question is a lot less fun when you're in between the two]]". The unstoppable force, in this case, is the [[InstantAIJustAddWater sapient robot population of Jean]] forming a society, which is going to happen regardless of whether they have human input or not; the immovable object is the {{terraforming}} process of Jean, which needs to stick to a very rigid plan in order to not go wrong and is largely dependent on robot obedience. In this case, when an unstoppable force meets an immovable object, [[spoiler:they pass through each other harmlessly; robots ''want'' to be workers, and are going to help with the terraforming process regardless, so things will go according to plan even as the robots form their society.]]

* In ''Anime/PokemonTheSeriesDiamondAndPearl'', Rampardos is described as the unstoppable force/spear that can break any shield and Bastiodon is described as the immovable object/shield that can't be broken. They battle. So you might be wondering what happens when Roark's Rampardos battles his father Byron's Bastiodon. The answer? [[EvasiveFightThreadEpisode The battle is interrupted due to Team Rocket before it can be resolved]].
* Alluded in ''Manga/Eyeshield21'', when Yamato (the original bearer of the title) and Shin (the antithesis of main character Sena) met, [[LightningBruiser both are considered the unstoppable Runner and the strongest Linebacker respectively]]. The result is sort of definite though, with Yamato managed to drag Shin with all his strength...at snail pace. To say the watchers amazed is an understatement.

* In ''Manga/TheLuciferAndBiscuitHammer'', Yukimachi and Subaru's paired attack and defense directly allude to this - they call their telekinetic attack "the Strongest Spear" and their telekinetic shield "the Ultimate Shield." They pick the names from a story shared by their teacher, the Master, about a spear that could penetrate any shield and a shield that could block any spear. In the hands of a single warrior, that warrior would be unstoppable. The Master then clasps their hands together, declaring the two together to be "the warrior."
* Referenced in the anime of ''Manga/{{Trigun}}'' by Hoppared the Gauntlet, who declares himself as an invincible shield and [[TheGunslinger Vash's]] guns as an unstoppable spear.
* Discussed in ''Manga/SaintSeiya'' during Seiya's early fight with Shiryu and even referred to as such. In a twist, Shiryu's in possession of ''both'': his shield is too strong for Seiya to breach while his Cloth has a right gauntlet just as hard on top of his considerably greater raw strength. Seiya ultimately solves the conundrum by tricking Shiryu into attacking him in such a way that when he dodges, he ends up punching into his own shield. [[spoiler:The shield breaks, but Shiryu also breaks the gauntlet and hurts his hand in the process and is forced to continue the fight without his Cloth.]]
* In ''Manga/{{Naruto}}'', the legendary Third Raikage possesses, on top of a [[LightningBruiser strong, tough body]], an [[ElementalArmor impregnable defense]] and [[UnblockableAttack indefensible offense]] through using his [[ShockAndAwe lightning chakra cloak]]. [[spoiler:The only way he could be wounded was to [[HoistByHisOwnPetard turn his attacks on himself]].]]

* ''Manga/TheSeveringCrimeEdge'': Apparently the reason why the Crime Edge (an indestructible sharp pair of scissors that can cut anything) can cut Iwai's otherwise unseverable hair.

* Referenced several times in ''Manga/{{Jormungand}}'' using the Chinese style pike vs shield version. Willey details the original parable in one of Jonah's lessons while the opening song for the first anime season "Borderland" contains the phrase "pike and shield" in English as a short hand for idea in the lyrics.

* ''Manga/{{Keijo}}'': Atsuko's butt ability is the "Ass of Vajra" (unstoppable force), which is used as a defensive and offensive move. However, when she used it as an offensive move against Non, it was rendered ineffective by the latter's Soft Buns (immovable object) move.
* ''Manga/DrStone'': When Senku shows off his paper shield design to his companions, Kinro expresses his doubt that a shield made from paper can block anything, using his spear to take down a tree with little effort. Senku decides to humor Kinro and tells him to strike the shield with everything he had. Kinro does just that... and the shield still holds. As it turns out, Senku glued molten plastic to each sheet to give it enough elasticity to absorb most of the impact.

* ''Film/{{The Avengers|2012}}'': Thor's Hammer vs Captain America's Shield. The result? The force of the impact doesn't hurt Cap, but is instead reflected into a shockwave that levels all the forest in their vicinity. The phrase isn't used in the movie itself but in the wider MCU, Thor's movie called his hammer the ultimate weapon and Cap's movie called his shield the ultimate defense.

* Used as a riddle in the far-future section in Ian Banks' "Walking on Glass". The actual answer is randomly tossed out in the other narrative. [[spoiler:The unstoppable force stops, the immovable object moves.]]
* Similarly, a Mensa puzzle book from 1991 uses this riddle as one of its logic puzzles. The answer is [[spoiler:an impossible event. Logically, the existence of one disproves the existence of the other by definition, and therefore the two cannot exist at the same time, therefore such an event will never occur.]]
* Only two people in the world of ''Literature/SoonIWillBeInvincible'' have "Invincibility" listed as a power.

* In ''The Fountains of Paradise'' by Creator/ArthurCClarke a reporter uses this phrase to describe the conflict between ace engineer Vannevar Morgan, who wants to build a space elevator on a mountain, and the abbot of a Buddhist monastery that has been sitting on top of the mountain for thousands of years.
* In ''Literature/TheGrimnoirChronicles,'' the characters Jake (a 'Heavy' able to [[GravityMaster control gravity]] and alter his density) and Toru (a 'Brute' equipped with SuperStrength) have this dynamic, though the spend most of their time as uneasy allies.
* In ''Mazeway'' by Creator/JackWilliamson, the main characters are repeatedly asked "What happens when the all-cutting blade meets the uncuttable stone?" [[spoiler:The blade is sharpened.]]
* {{Discussed}} in Creator/RobertLudlum's book ''The Ambler Warning'' by a Taiwanese presidential candidate during a campaign speech, prior to [[spoiler:being assassinated]]. The main plot is also thematically similar: a man with the intuition to SherlockScan anybody's true self realises almost too late that he's been deceived by a highly-trained [[MethodActing method actress]] as part of the BigBad's plot. But then, he was mostly pre-occupied with unravelling his true identity, after having been [[MindWipe Mind Wiped]] and given a false one.

* Used in the ''Series/KnightRider'' episode "Trust Don't Rust", to describe the theoretical outcome of a head-on collision between KITT and KARR. They refer to it as "Zeno's Paradox". It threatens to become no-so-theoretical when the only way to defeat KARR involves a GameOfChicken.
* In an episode of ''Series/TheAdventuresOfSuperboy'', a professor asks Superboy to help transport an insanely heavy totem pole, referring to the pole as the immovable object and Superboy as the unstoppable force. The totem pole was so heavy that even Superboy had difficulty lifting it. [[spoiler:The totem pole suddenly disappears as soon as it's completely out of its hole, releasing [[GreatGazoo Mxyzptlk]].]]

* ''Series/{{The Defenders|2017}}''. When Danny Rand punches Luke Cage, the result is a KungFuSonicBoom that knocks down everyone in the area, including Luke and Danny.

* In general, quite a few video game bugs can be caused by an object scripted to keep moving along some invisible course hitting some other object that cannot be moved. For example, in early builds of ''VideoGame/TheElderScrollsVSkyrim'', bees were given collision so that they could be picked up and collide with things, but could not be moved by any amount of outside force. This caused problems with the game's scripted intro (where the player is taken in a cart to be executed) where if a bee randomly flew in/spawned in the path of the cart, the cart (scripted to keep moving until it reached the destination) would hit the unmovable bee, causing the cart to launch itself into the sky.
* In ''VideoGame/WorldOfWarcraft'' there is a mace called Unstoppable Force and a shield called Immovable Object; both were among the easiest to obtain Epic gear and really good... until the release of the first expansion pack made them next to useless.
** There exist several anecdotes of players asking Game Masters what happens if the two meet, with supposed answers ranging from [[RealityBreakingParadox "Chuck Norris dies"]] to [[Literature/TheHitchhikersGuideToTheGalaxy "The answer is 42."]]
** This also inspired the {{Joke Weapon}}s Stoppable Force and Moveable Object, two pieces of ShopFodder that were useless even when they were first released, except for the little gold they brought.
* In the ''VideoGame/{{Suikoden}}'' universe, the True Runes were said to be born after the Sword that could cut through anything and the Shield that could stop any strike clashed.
* ''VideoGame/PerfectWorld'': A very early quest for human characters involves meeting the salespeople in Etherblade. Playing off the Chinese (spear/armor) version of this paradox, the blacksmith claims that his spears cannot be stopped by any armor, and the tailor claims that her armor cannot be pierced by any spear.
-->'''Player Character:''' [[DeadpanSnarker So if I bought one of the blacksmith's spears and tested it against your armor...]]

* Directly referenced in ''VideoGame/{{Tyranny}}'' while the player's Fatebinder is [[MushroomSamba high on hallucinogenic ink]]. Apparently, Rhogalus, Fatebinder of Lore, doesn't find the question enthralling.
--> '''Rhogalus:''' Absurd. In such a case, either [[StatingTheSimpleSolution the force is resistible or the object is moved.]]

* Referenced in Crowned Zacian and Crowned Zamazenta's Pokédex entries in ''VideoGame/PokemonSwordAndShield''. Supposedly Zacian's sword can "cut down anything in a single strike," and Zamazenta can "deflect any attack." Fortunately for the universe, this doesn't seem to be the case in reality, as [[GuideDangIt The Pokédex has been inaccurate many times before,]] and nothing's stopping Crowned Zacian from using [[SecretArt Behemoth Blade]] to [[GameplayAndStorySegregation KO a Crowned Zamazenta.]]
* Referenced by name in a achievement for ''VideoGame/TownOfSalem'' if a [[IncreasinglyLethalEnemy fully-powered Juggernaut]] attacks a transformed [[NighInvulnerability Pestilence]]. In this scenario, the Juggernaut dies while Pestilence survives. [[note]]In-game, this is because Pestilence's Invincible Defense cannot be breached by any means, whereas Juggernaut only has a Basic Defense against Pestilence's Powerful Attack.[[/note]] There's also a special message for this scenario (and everybody who sees it gets the achievement due to how rare it is, NOT just the Pestilence and the Juggernaut):
--> "An unstoppable force meets an invincible object. The ground beneath your feet shudders!"

* ''VideoGame/OnePunchManAHeroNobodyKnows'' has Saitama as a playable character, who's both the Unstoppable Force (able to defeat anyone with [[OneHitKill one punch]]) ''and'' Immovable Object (able to NoSell anything and everything.) It's possible to get two Saitamas to fight each other, and if this happens, both Saitamas are technically able to damage each other, but both remain ImmuneToFlinching, and when one's life meter reaches zero, they simply realize that [[SkewedPriorities Bargain Day at the local supermarket is almost over]] and they [[ScrewThisImOuttahere leave the fight]].
* ''VideoGame/DCUniverseOnline'': In the "World of Flashpoint" episode, [=Flashpoint!Batman=] reveals that the [=Flashpoint!Atleanteans=] and [=Flashpoint!Amazons=] have an unstoppable weapon and an unstopabbly shield, respectively. The goal of the "The Royal War" alert is to disable both the weapon and the shield.
* In ''[[VideoGame/NintendoWars Advance Wars]]'', you could have all the firepower boosts in the world and still not deal any damage to a unit with 200% defense or more due to how damage is calculated[[note]]base damage is multiplied by (2 - Defense/100)[[/note]]. ''Days of Ruin/Dark Conflict'' instead divides firepower by defense, ensuring damage is always greater than zero.

* An interesting variation occurs in ''VideoGame/Hitman2'' with Elusive Target Mark Faba, a.k.a. The Undying, Agent 47’s newest target who had managed to come back from being supposedly “killed” dozens of times. The mission essentially poses the question: what happens when a man who can kill anyone meets a man who cannot be killed? Considering that the mission repeats itself later with The Undying Returns, the answer is also interesting in that they both win: the man who can kill anyone does succeed in killing his target, and the man who cannot be killed comes back later anyway.
* ''VideoGame/MarvelSnap'' has its own take on the [[ComicBook/XMen Juggernaut vs. Blob]] scenario. Juggernaut's on-reveal ability moves all opposing cards played on his turn in his location, including unrevealed/face-down ones. Blob has an ongoing ability that prevents him from being moved once he's revealed. The winner in this case is "whoever reveals first" -- Juggernaut will move an unrevealed Blob, but Blob won't be moved if he's revealed first.

* ''WesternAnimation/BatmanTheBraveAndTheBold'' episode "Emperor Joker!" has [[ImYourBiggestFan Batmite]] describe Batman's relationship with ComicBook/TheJoker as such. Likely in reference to ''Film/TheDarkKnight'' quoted above.
* ''WesternAnimation/TheSimpsons'': Used on [[Recap/TheSimpsonsS8E3TheHomerTheyFall "The Homer They Fall"]] to describe the boxing bout between Homer (who has been discovered [[MadeOfIron to have a reinforced brain case and is theoretically knockout-proof]]) and returning heavyweight champion Drederick Tatum. Ultimately, this trope is defied -- Tatum is capable of punching so hard that Homer is on the verge of being knocked out (or even getting pummeled to death) ''[[EpicFail within ten seconds of the first round starting]]''.
* ''WesternAnimation/MightyOrbots'', when a techno virus drives non-sapient machines wild, Torr muscles it out with a bulldozer and quotes this with the bulldozer as the irresistible force and himself as the immovable object. [[spoiler:The immovable object wins when he tosses it into the air to end the stalemate.]]

* In ''Manga/{{Naruto}}'', the legendary Third Raikage possesses an impregnable defense and indefensible offense through using his lightning chakra cloak.[[spoiler:The only way he could be wounded was to turn his attacks on himself]].

** In ''Franchise/MasterOfUniverse'' crossover "ComicBook/FromEterniaWithDeath": Skeletor tries to break into the Castle Grayskull, but its gates remain undented after withstanding a blow which opened a rift in the fabric of reality. Later, after mind-controlling Superman, Skeletor wonders whether his unparalleled strength might succeed, and orders him to smash the gates down. Nonetheless, Superman breaks free of the spell before crashing into the doors, so the outcome of such a clash remains uncertain.

* {{Discussed}} in ''Literature/TheRisingOfTheShieldHero'': right before their duel, Motoyasu pointed out to Naofumi that, as the Spear Hero and the Shield Hero respectively, they were comparable to them... Before adding that Motoyasu's greater level (about twice Naofumi) and the Shield's lack of offensive abilities gave him the advantage. [[spoiler:Motoyasu wins... By unknowingly cheating: Naofumi had made the same reasoning and carried a number of Orange Balloons (the most basic monster mooks) on himself because they couldn't harm ''him'' but could cause at least some harm to Motoyasu, and thanks to that and a number of creative uses of the Shield's abilities (including a ''counterattack'' one) gained the upper hand until [[ManipulativeBitch Malty]] shot Naofumi with a wind spell in the back, allowing Motoyasu to pin Naofumi down and claim victory without realizing he had been helped]].

* [[Fanfic/WhereYouAndICollide This]] Transformers fanfic gives this role to Autobot Prowl and Decepticon Jazz and their relationship is further explored in the [[https://www.fanfiction.net/s/5578593/1/Where-You-and-I-Collide sequel]] as well as this bonus [[https://www.fanfiction.net/s/6159787/1/Addicted-to-You oneshot]].

** "[[VideoGame/DarkSouls1 Chosen Undead]] vs. [[VideoGame/TheElderScrolls Last Dragonborn]]" The former due to the Undead Curse can revive indefinitely as long as their sense of purpose persists. The latter is strong enough to battle and slay multiverse-devouring dragon demigods. [[spoiler: Dragonborn as the Unstoppable force wins as their power being superior to Alduin who could devour multiple infinite realities meant that the Chosen Undead who at best could temporarily refuel a universe sustaining First Flame wouldn't be able to put them down before eventually going Hollow.]]

* In ''Anime/{{Pokemon}}'', Rampardos is described as the unstoppable force/spear that can break any shield and Bastiodon is described as the immovable object/shield that can't be broken. They battle. So you might be wondering what happens when Roark's Rampardos battles his father Byron's Bastiodon. The answer? [[EvasiveFightThreadEpisode The battle is interrupted due to Team Rocket before it can be resolved]].

* Political pundits invoked this phrase more than once during the 2016 presidential election. The election was marked by a deep dissatisfaction with the establishment, resulting in the Republican nomination of businessman Donald Drumpf and a much better than expected showing from socialist Bernie Sanders in the Democratic primaries. This being said, Hillary Clinton was widely favored to win the general election on November 8, effectively preserving the status quo of the Obama years. Almost fittingly, the final election result reflected both of these political zeitgeists simultaneously... Hillary Clinton won the national popular vote while Donald Drumpf won the electoral college and the presidency.

* Political pundits invoked this phrase more than once during the 2016 presidential election. The election was marked by a deep dissatisfaction with the establishment, resulting in the Republican nomination of businessman Donald Trump and a much better than expected showing from socialist Bernie Sanders in the Democratic primaries. This being said, Hillary Clinton was widely favored to win the general election on November 8, effectively preserving the status quo of the Obama years. Almost fittingly, the final election result reflected both of these political zeitgeists simultaneously... Hillary Clinton won the national popular vote while Donald Trump won the electoral college and the presidency.

* {{Discussed}} in Creator/RobertLudlum's book ''The Ambler Warning'' by a Taiwanese presidential candidate during a campaign speech, prior to [[spoiler:being assassinated]]. The main plot is also thematically similar: a man with the intuition to SherlockScan anybody's true self realises almost too late that he's been deceived by a highly-trained MethodActress as part of the BigBad's plot. But then, he was mostly pre-occupied with unravelling his true identity, after having been MindWiped & given a false one.