Where a character displays a complete lack of understanding about culture, behaviour, social norms or other things that they should, by their own backstory and the world they live in, know. They don't have a plausible Fish out of Water excuse like Time Travel into the past or future, or just arriving on a different planet, or even another country — they should know this stuff already. However, due to the Rule of Perception, if the audiences don't know about it, someone has to explain it.
Like Ping-Pong Naïveté, except instead of back-and-forth, it's stalled completely except when the character's in front of a camera. The alternative to As You Know, since it's bizarrely "As You Don't Know." See also Genre Blind, which is similar to Culture Blind except that it extends to a character's entire reality.
May be used when Deliberate Values Dissonance would be far more plausible.
The Amnesiac Hero is one way writers get around this. After all, it's okay for him not to know if he's forgotten, right?
Of course, people like this do exist in Real Life, although probably not to the extreme degree that they do in fiction; some people, for whatever reason, just don't get out much, listen to the radio, or watch the news. In addition, people with Autism or Asperger's Syndrome may not understand acceptable forms of behaviour due to the very nature of their conditions.
- Ash Ketchum from Pokémon knows surprisingly little about Pokémon during the Kanto and Unova seasons, considering that the entire world is obsessed with them, and he's more obsessed with them than anybody else. Notably, Iris calls him out on this quite a bit during his stay in Unova.
- At least Naruto himself is a dumbass, but one wonders exactly what they've been studying for years prior to the beginning of the show since every single thing needs to be explained. Naruto didn't just skip classes, he put his ninja skills to use in order to escape in the middle of lessons. He also grew up as a social outcast. His lack of knowledge is in his case partially justified.
- The other characters, though, have no excuse for their apparent lack of knowledge about the abilities of the other clans from their own village, which is most evident during the Chuunin Exam arc.
- Miaka from Fushigi Yugi. Sure, she traveled into the past to ancient China... but some of her actions can't even be justified using that as an excuse. One example that stands out is in the beginning, when she was with Tamahome watching the Emperor's procession in the city. Tamahome jokes that in exchange for his help, he wants her to get him a jewel off the Emperor's hat. She then actually proceeds to run up to the Emperor's palanquin, yelling for the Emperor to give her a jewel from his hat, and proceeds to grab at the palanquin and break part of it. And she acts shocked when the soldiers grab her and attempt to execute her. Think about it for a second in equivalent terms of a modern-day society: She runs up to the prime minister's car, grabbing at the car door and breaking parts of it, while screaming demands for the PM to give her ¥50,000. Miaka must have been living under a rock all her life, because no ordinary high school student (who supposedly gets high marks) would think (when not under the influence) that that would be a good idea.
- In Hunter × Hunter, the first arc of the story has Gon and Killua understanding their world and culture just fine. And then the second arc comes... and all of a sudden, everyone except Gon and Killua know all about the techniques of Nen, Ren, Zen, etc. and have apparently known about it all along. So they end up having to start from the beginning, learning the basics and everything about it. It makes one wonder how in the world neither of them (who were actually considered strong in the first arc) were ever taught anything about it. It especially doesn't make sense in Killua's case, since he was supposed to come from a super powerful family of assassins.
- Justified, Nen is a closely guarded secret, learning it exists and how to use it is part of the hunter trial secret test. Killua is also justified in not knowing about it because this is a world in which Charles Atlas Superpower are a real thing for a person's physical strength as well as their Nen.
- Exists in Eyeshield 21, as the anime is about American football, something relatively unknown in Japan. One big example is a news reporter who came to the Devil Bats vs. White Knights game solely to cover athlete/model Haruto Sakuraba, and kept asking questions about how things worked. And on more than occasion an outsider has mistaken the game for rugby. Additionally, NASA Aliens receiver Jeremy Watt is an Occidental Otaku whose actual knowledge of Japanese language and culture is extremely limited, and often hilariously flawed. The fact that it's set in Japan justifies a lot of the explanations given in the story. The commentators, for example, are mostly there to explain basic rules to the audience (in-story), who often mistake the game for rugby. Had the story taken place in America or been aimed at Americans, having to explain something as basic as "what is a touchdown" would seem downright insulting. Jeremy Watt, however, is just a Cloudcuckoolander.
- Gino Weinberg of Code Geass knows little about civilian life being a clueless nobleman.
- Similarly to Gino, Louise from The Familiar of Zero knows just as little about civilian life, as she comes from a noble family and lived either on their estate or attended a Wizarding School which is also exclusively for nobles who show little to no interest in the non-noble parts of the staff. This actually does come back to haunt her when she blows all her traveling money in a casino and has to take up a job as a waitress in a not-entirely-clean café/bar - and fails miserably at it.
- Characters in Chick Tracts never know anything about Christianity (usually even being ignorant of Jesus or the religion itself), even if they're from countries that are overwhelmingly Christian.
- Averted in Alley Oop. The titular caveman has been time traveling between his prehistoric world and the present day for years, and by now he is completely fluent in modern culture. This gets lampshaded whenever one of his caveman friends ends up time traveling with him and sees the modern world for the first time.
- Fantasy of Utter Ridiculousness: Alice realizes this about Coop when he, not only as a visitor to her home but also to Gensokyo as a whole, gave her something to drink instead of the other way around.
- Conversed in Through a Diamond Sky when Flynn is assuring Tron that the Isos mean no harm, they're still learning.
Flynn: They're new to life and they're still learning the system. Given time, they'll integrate. I'm sure of it.
Tron: You are sure?
Flynn: Dude, how awkward was I when I first got zapped in here?
Tron: Let's see? First words out of your mouth were blasphemy, you completely ignored the rules of the light-cycle matches, you had no idea what to do with an energy spring, and you made a pass at Yori.
- In Mulan II, Mulan is shocked when she hears that three princesses have been betrothed in an arranged marriage. This shouldn't surprise her, as it is most likely one of the most normal things in the world where and when she lives, and her own marriage to Shang for love is probably a huge exception. Especially considering that the first film begins with Mulan flubbing her meeting with the Matchmaker in an attempt to get an arranged marriage herself. That's why fans don't really talk about the sequel.
- A rather fatal example comes from the series The Tamuli by David Eddings. The church of Elenia continuously sends missionaries to the Rendors in order to try to convert them to their beliefs. Mind you, the Rendors aren't bad people, but they take their religion very seriously, and while they usually don't go around slaughtering nonbelievers, they are very easily angered, especially when it comes to religion. And unfortunately, the missionaries that the Elenes send tend to be the screaming zealot type, and go around ripping the veils off of women, and screaming that they're all heretics and damned to burn in hell. The end result is a small riot, and a lynched missionary, for very obvious reasons.
- One knight, who had been assigned to be the bodyguard of a missionary that ended up this way, was asked why he didn't stop the crowd from lynching his charge. His reply is that he was supposed to protect the man from unprovoked attacks, and when a man runs through the streets of a foreign city, ripping the veils off of women, and screaming out that they're all heretics, he's not only provoked them, but is obviously too stupid to risk himself and his men trying to save him.
- The Big Bang Theory: Sheldon Cooper. Although some of that could be because he's a) an example of Comedic Sociopathy and b) a long way along the Asperger Syndrome Diagnostic Scale.
- When he refuses to buy Leonard a birthday present, Howard encourages Penny to tell Sheldon that it's a "non-optional social convention," at which point Sheldon happily capitulates.
- Bones: Another example, although less blatant, is Brennan. Although she's focused primarily on her work, she displays a remarkable ignorance of current culture, which is odd given that she clearly wasn't always like that (she's a Wonder Woman fan, likes classic rock, but still has no idea what's in any movie or TV show released in the last 20 years).
- The novels were eventually justified. Apparently Brennan is so Culture Blind that she didn't realize people were reading her books for the sections of them that Angela wrote rather than her rigorous scientific accuracy.
- Culture blind? Temperance Brennan is so dedicated to science and the intellect that she is Life blind, ignorant of some of the basic niceties and courtesies of human society. In one episode she and Booth enter an interrogation room to...well, interrogate, an obese woman. Booth remarks on a peculiar smell in the room and Brennan proceeds to tell him that it is coming off the woman in the room and is created by a fungus that grows in the fat folds of the morbidly obese, while standing within three feet of her. The subject of the verbal monograph is not amused, and Brennan is taken a bit aback because she was "only telling the truth." In another episode, Bones and Booth go to see a man about a case and find him engaged in a small outdoor religious ceremony (memorial service?). They pause before approaching the group to discuss the case - and further the plot - and as they do the group begins a prayer. When the plot has been sufficiently furthered Bones steps off to approach the man they're there to see and Booth grabs her arm - "Wait a minute, Bones." *points* "Praying?" Brennan gives him a look of complete oblivious confusion and says, "But we're not members."
- This is especially strange since she is an anthropologist, meaning she studies cultures, both past and present. And yet she's completely ignorant of her own culture. When they go to New Jersey, she treats the locals like a backward tribe of some sort, claiming to have watched something on TV about this culture (i.e. Jersey Shore) and tries to put some of the "rituals" she saw to use. Booth is both confused and embarrassed.
- In the case of the obese woman Bones is purposely being offensive, since they're trying to track down the woman's son, an escaped serial killer. They're hoping to upset him by bringing in his beloved smother, so any other offense is icing on the cake. However, most other times she's being obtusely offensive. It's like she thinks her observations are taking place on the other side of a One Way Mirror so she can't be heard or seen.
- She's a PHYSICAL anthropologist, not a CULTURAL or SOCIAL anthropologist. There's a difference.
- Brennan's cultural blindness could be explained by her Ambiguous Disorder... which was eventually revealed to be an actual disorder, with her having Asperger's Syndrome.
- Friends: Probably a case of Flanderization as he became dumber as the series went on, but Joey seems to display a shocking ignorance of how anything actually works in the entertainment industry, despite being a professional actor with many different roles over the course of the series.
- The Office (US): Michael Scott from the American version could be this trope's poster child. His misunderstanding of other races and cultures is massive.
- Revolution: Granted, Charlie Matheson has been purposefully kept sheltered for most of her life and their settlement is supposedly out of the way...but how does someone spend 15 years growing up in a post-Blackout world and still not fully grasp how things work there? Fortunately, she has come a long way since then.
- Star Trek: The Next Generation: Classic example is Data. Although his backstory has him serving in Starfleet for almost two decades after he was discovered and before he's assigned to the ship, apparently no one bothered to talk to him for all that time because it's only when he arrives on the Enterprise that he starts learning about things like aphorisms, clichés, common sayings, human social behaviour and the like.
- Data, at least, was somewhat justified in the Expanded Universe; in the prequel novel The Buried Age, Picard discovers him working as a records clerk in a backwater spacestation, where he's largely treated as a machine, not a person, so no-one does talk to him, except to make specific requests. (That still doesn't explain how he got through the Academy without ever hearing the phrase "wild goose chase", of course.)
- Worf, as well, should act as human as Riker. He's raised among humans, knows human values and ethics, but acts as if he's fresh off the boat from Quonos most of the time. While it doesn't excuse outright ignorance, a lot of his failing to fit in is implied to be overcompensation for just that. He is described as having spent much of his time growing up embracing his heritage and trying to be as Klingon as possible in Human society. That combined with his formative years being among Klingons, makes it pretty reasonable. Guinan hangs a lampshade on this in one episode, telling him outright that most Klingons do not act as stiff and stoic as he does.
- His stiff nature is itself lampshaded and explained in a later episode of Deep Space Nine, when he explains that as a youth living among humans, he accidentally killed another boy with a head-butt during a soccer match. It was accepted as an accident by everyone involved, but he realized how frail humans were compared to him and decided that to live among them, he had to always stay in control of himself.
- Alternatively, his attitude is fairly standard for a stereotypical Russian, and his adoptive parents are indeed Russian. Although the particular Russians that adopted him, are still nothing like him.
- Datak Tarr in Defiance, a Castithan community and underworld leader in the titular town. He constantly views everything around him from his own culture's viewpoint and doesn't understand why humans don't act more like Castithans (who bathes alone?!) or treat him with more respect by virtue of his high caste. For reference, the events take place on Earth, meaning Datak should really learn the customs of the people whose homeworld he lives on.
- Dungeons & Dragons: Tritons are a kind of merfolk who are Lawful Good and spend most of their time battling extradimensional threats to the world's oceans. Unfortunately, since deep ocean isn't an environment well-known to other races, merfolk are unpleasantly surprised to find that no one from the surface has heard about or even cares about their (genuine) accomplishments despite it being obvious why they're unheard of.
- Final Fantasy X-2 encourages the player to explore the Bikanel Desert so as to learn the Al Bhed language. Ignoring the fact that, if you are a returning player, you had the chance to learn the language in the previous game, one of the main playable characters in this game is an Al Bhed and was previously established as fluent in the language!
- Princess Elodie of Long Live the Queen starts out with no knowledge of basically anything, despite having been away at boarding school for several years. Though her lacking royal etiquette is explained by said school having placed little emphasis on its students' social classes, that still doesn't excuse her cluelessness about her own country's history and geography.
- Riff from Sluggy Freelance apparently didn't know that people get weekends off from work. It's somewhat justified since he had never worked a 9-to-5 job before, but even so that seems like something he should have picked up from TV or something.
- Much like Ash, Atticus from the Pokémon fancomic Mokepon is generally clueless about how his world works. In his case, however, it's because he simply never cared about the whole "amazing, life-changing adventures and friendships" that his world revolves around.
- In Noob, Omega Zell wants to become the next top player of the game, and part of his plan is to join his faction's top guild. However, he has several times shown to completely ignore the requirements to join beyond being level 100, such as actually learning high-level play strategies, having the best gear he can manage and being maxed out at the game's reputation system. There has been an occasion or two upon which his rival in all but name Gaea has shown to know more about these requirements than he does.
- Although alot of the characters in Deagle Nation are slightly oblivious of other cultures, Eli is so culture-blind that he barely seems to understand his own culture.