Know-Nothing Know-It-All



""Professing themselves to be wise, they became fools.""

- Romans 1:22

A Know-Nothing Know-It-All is a character who insists he or she knows everything; is always right; that they were the actual original creator of an idea; and who generally has an extremely high opinion of themselves and their abilities.

Nothing could be farther from the truth. They are grossly misinformed, or just lying, about everything they talk about with authority. They create nothing new, and are Ignorant of Their Own Ignorance. Their abilities could best be described as "scarce". Such people are, in fact, the living definition of the word charlatan.

While many characters show signs of being this, very few have it as a major facet of their character. For example, Peter Griffin of Family Guy tends to spew horribly misinformed information, but oddly enough, sometimes he's right, in the rather odd world the series is set in.

Little-Known Facts are occasionally in the Know-Nothing's mental arsenal, thanks to their obtuse quality, but naturally, the research won't be.

Can sometimes intersect with the Jerkass. Compare Feigning Intelligence. Contrast Insufferable Genius, who has the same arrogant attitude but is not incompetent. Actually listening to one may result in The Blind Leading the Blind. Compare Small Name, Big Ego, who both want to be recognized and appreciated, but take different paths to it. For a more "physical" version, see Boisterous Weakling.

Anime & Manga

 * Autor from Princess Tutu fits this trope to a T... at least at first. He's an insufferable know-it-all who believes that he's a descendant of Drosselmeyer and also the absolute expert on the subject of his powers. He puts another character who wants to learn about his powers through a series of ridiculous 'training' exercises, including standing in the middle of a room for three days without eating or sleeping and only using "blue and black ink in a seven-to-three ratio". Eventually he's humiliated when the character he's training proves to have much more power than him... if he ever had any power at all. In the end it's slightly subverted, however—the character he "trained" is forced to go back to him for help because he actually is one of the best experts on Drosselmeyer.
 * In Axis Powers Hetalia, South Korea always claims he invented everything (well, almost everything. No one takes responsibility for condoms).
 * Truth in Television: Some Koreans enjoy claiming that they invented or influenced a great deal of things. Like Chinese New Year, seismographs, paper, etc. Hell; at one point, it was said that they claimed Michael Phelps was part-Korean. ... which was actually a false claim by the Chinese media, exaggerating that particular stereotype of Koreans.
 * Takashi Yamazaki from Cardcaptor Sakura is always making up lies he claims to be facts. Interestingly enough, while most know he's lying, both Sakura and Syaoran both tend to believe him at first, before Chiharu breaks it to them that they're being lied to and lays the smackdown on Yamazaki.
 * Onsokumaru in Ninin ga Shinobuden.
 * Umino Gurio in Sailor Moon.
 * Sakuragi Hanamichi from Slam Dunk is actually pretty stupid but always goes around saying "Ore wa tensai!" (I am a genius) and "Ore wa tensai baskettoman!" (I am a genius basketball man)
 * One episode of Lupin III featured Sherlock Holmes III among a group of detectives hired to outsmart Lupin. In the original version, he was a cultured gentleman. The Geneon Gag Dub turned him into a total nitwit who is always either stating the obvious or completely ignorant of the obvious—for instance, upon noticing an opulent dining fork, he proclaims it "a dining implement of some kind; a bit showy, whatever it is." Granted, the Holmes seen for most of the episode is actually Lupin in disguise, and when the man himself gets a chance to talk he seems pretty on the ball.

Comic Books

 * Jack Chick. Beyond his tin foil hat theories about the Jesuits founding communism as part of a centuries-long plot to get Russian gold, he even manages to get very basic facts wrong. Like claiming that Kaiser Wilhelm II was Catholic.

Film--Animated

 * Scuttle the seagull from Disney's The Little Mermaid. He claims that a fork is a thing for styling hair, a (smoking) pipe is a musical instrument, and also uses a telescope backwards.
 * This gets Lampshaded later on in the film when he's trying to warn Sebastian about something. Sebastian is understandably skeptical, and Scuttle shouts "Have I ever been wrong? I mean, when it's important?"
 * Friend Owl from the Disney's Bambi. The 'advice' he gives Bambi and his friends is actually terrible advice to give to young animals. Fortunately, it mostly gets ignored once "twitterpation" sets in.
 * And then there's Timon in The Lion King.
 * Jasper in 101 Dalmatians. His shtick with Horace is that Horace hits upon what's really going on and then Jasper emphatically calls him an idiot for getting such a stupid idea.

Film--Live Action
"Wanda: To call you stupid would be an insult to stupid people! I've known sheep that could outwit you. I've worn dresses with higher IQs. But you think you're an intellectual, don't you, ape? Otto: Apes don't read philosophy. Wanda: Yes they do, Otto. They just don't understand it. Now let me correct you on a couple of things, OK? Aristotle was not Belgian. The central message of Buddhism is not "Every man for himself." And the London Underground is not a political movement. Those are all mistakes, Otto. I looked them up."
 * Otto, the Bombastic Jerkass Nietzsche Wannabe American psychopath in A Fish Called Wanda.

"WALT: 'Death is bittersweet? Bitter in the pain, sweet in the salvation.’ That’s what you know of life and death? Good God, it’s pathetic. FATHER JANOVICH: What do you know, Mr. Kowalski? WALT: Plenty. I lived with death for three years in Korea. We shot people, we stabbed them with bayonets, we hacked seventeen-year-old kids to death with shovels, for Christ’s sake. I did things that won’t leave me till the day I die, horrible things, things I have to live with. FATHER JANOVICH: And what about life? WALT: has to think for a second. He struggles with his answer: Well... I survived the war... got married... and raised a family. FATHER JANOVICH: Sounds like you know more about death than you do living. WALT downs a shot. Maybe so."
 * Jimmy from Barbershop is only working at the shop to pay his way through college, and he tends to lord his superior education over his fellow workers. Problem is, he frequently gets his facts wrong, such as when he corrects another character by saying that scallops aren't mollusks (they are) and that a local store owner is Pakistani, not Indian (no, he's definitely Indian and quite resents being called Pakistani, thank you very much).
 * Zelig, who has the uncommon ability to blend in and be mistaken for someone important, despite knowing very little, is somewhere between this and Seemingly-Profound Fool.
 * Inverted in The Monkees’ 1968 movie, Head. Peter, frustrated that the guys wouldn’t listen to him after warning them about the “Black Box,” makes them sit down to listen to his highly intelligent philosophy passed down to him by the Swami earlier in the film. His monologue closes with: “But then…why should I speak, since I know nothing?”
 * Paul, the "pseudo-intellectual" in the Woody Allen film Midnight in Paris acts like an expert on general Parisian art and culture, but is proven wrong several times. It doesn't stop him though.
 * Gran Torino: Invoked and played straight: Just after Walt accuses Father Janovich of being this after hearing his wife's funeral speech, Father Janovitch asks him what Walt knows. Walt realizes that he knows plenty about death, but not a lot about life.

Literature

 * Gilderoy Lockhart from Harry Potter initially appeared to be one of these, although in the end it turns out he's well aware of his own incompetence.
 * Sergeant Colon from the Discworld series is a mild version of this. He does consider himself well informed, but the only person he tries to impress this on is Nobby Nobbs, who he's aware may be winding him up. Such as when Colon identifies hieroglyphs as a type of mollusk, and is asked if they go lower they'll find loweroglyphs, and decides to go for broke - everyone knows you don't get loweroglyphs in these waters. It is said he had a broad education; he went to the school of 'my dad always said', the college of 'it stands to reason', and is now a post graduate student at the university of 'what some bloke told me in the pub'.
 * Most members of the UU faculty also display a strong tendency towards this trope. Everyone, that is, save Ponder Stibbons, who occasionally fakes it, spouting his own ridiculous explanations because he knows the real facts will only kick off another off-topic argument among his colleagues.
 * Part of this phenomenon, in the case of the wizards at least, may be attributable to the fact that (much like real-life scientists up until about the turn of the twentieth century) they consider new breakthroughs to be gross discourtesy rather than something to strive for.
 * Yes, everyone except Stibbons, the Bursar (who can actually translate Stibbons' explanation into layman's terms), Ridcully (who is definitely Obfuscating Stupidity) and the Librarian.
 * And of those four, the Bursar is insane, the Librarian is an orangutan, and Ridcully is not averse to flying off into tangential arguments of his own. Though, again due to Obfuscating Stupidity, he could be doing that on purpose.
 * Granny Weatherwax does this as well, insisting that elephant is "a kind of badger".
 * Owl from Winnie the Pooh.
 * Yefrem Levitan's educational Book About Stars & Planets features a self-praising gnome's wild stories about his supposed space adventures; the readers' objective is to find all the flaws in his stories, and there are many.
 * Brother Verber, from Joan Hess's Maggody mysteries, recites Bible phrases at the drop of a hat. As he's the inept product of a fly-by-night correspondence-course seminary, he constantly misquotes them, mistakes their verse numbers, and/or takes them so far out of context as to be irrelevant.
 * This is pretty much the defining personality characteristic of Stingray from Toys Go Out and its sequel Toy Dance Party.
 * The character Jesse Honey, in Mark Helprin's Winter's Tale, thinks he knows everything but is laughably incompetent, and takes any critique as a shot at his diminutive height. It gets him and another character into trouble or injured several times, . Another character, Juliet Paradise, is a self-proclaimed intellectual who is noted to believe that a goat is a male sheep.
 * Mary from Pride and Prejudice can be read as one. The book implies that while she studies hard, she doesn't take in much and can learn the mechanics but not the soul of what she studies. It's shown most during the brief times she's allowed to talk, where she almost always moralizes about obvious things with all the arrogance and pride of someone making a great discovery.
 * Kirtan Loor from the X Wing Series has a Photographic Memory and, because of it, thinks himself a genius and is always surprised when his plans don't work. Early in the series he's taken before the Big Bad and lambasted for his flaws, most notably a tendency not to think. For the rest of the series he proceeds believing himself to have changed, but one or two insights aside he really hasn't.
 * Most of the humour in Kaz Cooke's Little Book of X..er...books comes from the author taking this role, providing "advice" on whatever subject that is one million per cent useless. The Little Book of Beauty suggests the use of wood glue for hair care, for Pete's sake.
 * Mark Twain discovered one of these among his fellow passengers on the trip he took in The Innocents Abroad. Dubbed "The Oracle," his hilariously inaccurate observations (like pointing out "the pillows of Herkewls" in the Strait of Gibraltar) were encouraged by the other voyagers.
 * Eliza in Someone Elses War is quite bossy, but rarely ever in-the-know.

Live-Action TV
"Well ya see, Norm, it's like this. A herd of buffalo can only move as fast as the slowest buffalo. And when the herd is hunted, it is the slowest and weakest ones at the back that are killed first. This natural selection is good for the herd as a whole, because the general speed and health of the whole group keeps improving by the regular killing of the weakest members. In much the same way, the human brain can only operate as fast as the slowest brain cells. Excessive intake of alcohol, as we know, kills brain cells. But naturally, it attacks the slowest and weakest brain cells first. In this way, regular consumption of beer eliminates the weaker brain cells, making the brain a faster and more efficient machine. That's why you always feel smarter after a few beers."
 * Cliff Clavin of Cheers, to an extent that he was the original Trope Namer. He inherited his "gift of gab" from his mother, Ma Clavin. The big difference is that Esther actually knows what she's talking about, despite being a know-it-all herself.

"Charlie: This bar runs on trash. It's totally green now. Dennis: How is burning trash green? Charlie: I could stick it in a landfill, where it's gonna stay for millions of years, or I could burn it up and let it disappear into the sky where it turns into stars. Mac: That doesn't sound right, but I don't know enough about stars to dispute it."
 * As a trivia note, Cliff was not part of the original Cheers concept. He was added when John Ratzenberger convinced the producers that they needed a typical bar know-it-all. His improvised performance at an audition sealed the deal.
 * From time to time, he did actually get things right, and on other some other occasions he was cut off before he actually spewed anything that was incorrect.
 * Diane Chambers and Frasier Crane, in contrast, were the Insufferable Genius foil to Cliff.
 * John Ratzenberger, who played Cliff, said that Cliff, according to Cliff, was "the wing nut that held civilization together." According to Ratzenberger, Cliff is just a winged nut.
 * Mr. Chekov, of Star Trek fame, thought that everything, from genetically modified wheat to the written word was a Russian "inwention". Given that the show was made during the Cold War, he was never right about any of it. This is actually Truth in Television, as Soviet propaganda tried to trace many things to Russian inventors, to the point when people started joking that "Russia was the homeland of elephants", or the greatest inventor of all time, Lenard da Vishinski.
 * This attitude of Chekov was spoofed in a novel by Diane Duane, when he claimed that roller coasters had been invented by Russians. Nobody believed him, as the first roller coaster had been patented by an American... Yet, Russians actually created the ancestor of roller coasters, the Russian mountains, and in many languages (like Italian or Portuguese) the roller coasters are called with the local translation of Russian mountains.
 * In the original The Twilight Zone episode "Hocus-Pocus and Frisby" (under the late great Rod Serling), a small-town bumpkin was this, and everyone around knew it. Except the aliens (who had never evolved the concept of lying) who overheard him, mistook him for the greatest human brain ever, and kidnapped him for their zoo. He escaped through courage and dumb luck. And when he tried to tell people ... Crying Wolf, anyone?
 * In a slight departure, Stephen Colbert of The Colbert Report portrays himself as an extremely far-right Republican Know-Nothing Know-It-All.
 * For that matter, many most TV pundits in the US are like this; parodying this was the original premise behind The Colbert Report.
 * Which ended up lampshading itself when an Ohio State study in 2009 showed that many conservatives don't realize that Colbert's show is a parody and believe that he is sincere.
 * Kathleen from Degrassi Junior High is a borderline case. She really does know more than the rest of the cast, but she's such a Control Freak that this knowledge is rarely relevant to anything. She drives a science fair judge crazy by reciting every stack of facts she knows, never giving her partner a chance to talk, and is shocked when that doesn't earn her first prize. A Running Gag on the show is that when Caitlin (the overachieving School Newspaper Newshound) needs to come down to earth a bit, it always happens by Kathleen doing something better than her—which is the most humiliating thing possible.
 * Reversed in Hogan's Heroes, where Schultz was always quick to assure people that he "knew nothink!", when in fact he knew more about Hogan's operation than any of the other Germans.
 * Parodied in The Red Green Show in the segment where they examine the three hardest words for a man to say: "I DON'T KNOW!" Thus, the guest is always morphed into one of these.
 * Played straight with Hap Shaughnessy who, in any episode that features him, claims to have invented a common item or to know the reasoning of historical figures due to him being there when they made their decisions (if he wasn't responsible for them making the decision in the first place).
 * In The Muppet Show, Sam the Eagle claims to value culture, but in reality he's a complete ignoramus with the arts. For instance, he didn't recognize the world famous ballet dancer, Rudolph Nureyev, in street clothes and thought William Shakespeare was a composer.
 * More recently, he tried to sing (karaoke, cause it's a nice American activity, even!) "American Woman" in one of their new YouTube videos. When the machine told him it was by The Guess Who, he hazards, "Um, I don't know...John Philip Sousa?" before trailing off halfway through the third or fourth line, demanding to know who was responsible for the blatantly anti-American lyrics. And he really flips it when Kermit tells him The Guess Who is a Canadian band.
 * Paul Kinsey of Mad Men. Perhaps his defining quote in the series wasn't actually said by him, but rather about him; "We get it, you're educated."
 * Pretty much all of the main characters in It's Always Sunny In Philadelphia.

"'Yes, my friends, do you realize you can live to be a 127 years old... if you listen to Petrov? '"
 * Danny Kaye had a number of characters who were this. Though most of them were one-offs.


 * Sheldon Cooper of The Big Bang Theory is normally a straight-up Insufferable Genius. However, once you get him out of physics and onto biology, his knowledge gives out very quickly. His opinion of his knowledge, on the other hand, does not.
 * Neelix of Star Trek: Voyager claims to be competent at many things (diplomacy, navigation, survival, cooking...) but he fails almost every task he's given. Sometimes it's hard to tell whether he's supposed to be this trope, or if they're Informed Abilities.

New Media

 * At least half of any given fandom regarding the fandom itself. Especially the "Stop Having Fun!" Guys and Scrub in fandoms that have them.
 * Truth in Television: Just go on a Message Board. You'll get loads of total idiots experts on many subjects.
 * Played straight and averted by 4chan. This is a product of the fact that users of some boards completely loathe all the other boards. Interest based boards commonly avert this, and are somewhat filled with level-headed individuals who are generally intelligent and well informed in regards to the board's topic (/co/, /tv/, /sci/, /lit/, and even /a/ on a good day). The rest of the site tends to play this straight though, particularly the more easily trolled boards. /new/ is quite possibly the worst offender, as at least 50% of its userbase are superbly ignorant Neo-Nazis who spam The Bell Curve, with the other 50% composed of trolls posing as strawman liberals or conservatives.

Newspaper Comics

 * RJ the raccoon from the comic strip Over the Hedge (not so much The Movie) makes up explanations for everything to the gullible woodlanders (to the annoyance of Verne, who usually has the accurate answer but can't explain it in a way anyone will understand).
 * Bucky Katt of the comic strip Get Fuzzy.
 * This was one of Lucy's main traits in earlier Peanuts strips. She thinks that snow falls up, fir trees literally have fur on them, and that a chain line is so that climbers can all fall of mountains and die together instead of it having the exact opposite purpose (so that the climber falling doesn't fall to his death because the others are holding him up).
 * Calvin and Hobbes: Calvin's dad does this sometimes when Calvin asks him questions, but he's doing it on purpose. Like claiming the wind was caused by trees sneezing. Watterson's commentary says that he assumes it must be a great temptation for real parents not to abuse their power for pranks.
 * Then there's Calvin himself. Bats are not bugs, by the way.
 * Despite the picture above, Hobbes is not usually an example: math just isn't his strong suit. Why Calvin keeps asking him for help after all the bad grades he must get is something of a mystery.
 * Possibly because he's in Calvin's head, and no smarter than Calvin at his best. Word of God states that one reality is Calvin's immature point of view, while the second is an adult point of view, and the reader can decide which is true.

Theatre

 * The character of Dottore in classic Commedia Dell'Arte is often played as smugly satisfied with his own learning, despite his ineffectiveness. In a script that cast him as a medical doctor, for example, he would speak perfect Latin, but his patients would all die.
 * This is Slightly's shtick in Peter Pan (and any incarnations thereof in which he appears). While none of the Lost Boys remember anything about life before they joined Peter's band, Slightly is constantly faking knowledge, convinced that he remembers himself.
 * Sheridan's play The Rivals gives us Mrs. Malaprop, who liked to use big words in an attempt to sound more educated than she was. Of course, she uses the wrong words, and Hilarity Ensues. Mrs. Malaprop's antics are the source of the word Malapropism.

Video Games
"By the way, Rinnosuke's supposed vast storage of knowledge comes almost entirely out of thin air. Indeed, he doesn't know nearly as much as he thinks he does. If you read closely, you'll notice a lot of wild, meta ideas, but I think that's supposed to be the joke."
 * Axel gives hints of being this in 385/2 Days, when he talks about why the sky turns red.
 * Theodore from Persona 3 Portable claims to know all about the human world, but its fairly evident that he's totally clueless about human interaction in general.
 * Rinnosuke of Touhou. You know all those descriptive first-person narratives he makes in Curiosities of Lotus Asia that seem to describe the inner workings of Gensokyo? Well, as ZUN reveals in the Afterword...


 * The Fact Sphere from Portal 2.

Webcomics

 * Qui-Gon (or at least his player, Jim) in Darths and Droids. Whenever the Game Master makes up a word Jim insists he knows what it means, be it "Jedi" (It's a type of cheese), "Naboo" (Fish oil mixed with liquor) or "midi-chlorian" (exactly the same as Star Wars midi-chlorians; in this case, the GM just threw up his hands and went with his explanation, even though it was totally ridiculous).
 * Although it was reversed when the DM used the term "Vergence", which he thought he had made up but which Jim actually knew the definition of. Turns out he's not the idiot he seems, and is working on a Ph.D in geophysics. He just likes to "turn his brain off" when gaming, turning him into a Genius Ditz when something burns through the fog.
 * King Steve from 8-Bit Theater. Completely insane, but how do you argue with someone who "invented inventing"?
 * Also Red Mage to some extent.
 * "To some extent?"
 * The Furry Webcomic Nip and Tuck, by Ralph Hayes, Jr., uses the fact that he is this as one of the reasons to justify Gilly Gopher as being the Butt Monkey that he is.

Web Originals

 * Ask That Guy is a particularly psychopathic version of this.
 * A less insane (but only slightly) version from the same site would be The Nostalgia Chick. Best showcased in the X-Men review, where normal!Chick brushes off Dr. Tease with "I know everything", and Chick on Truth Serum admits that the mutant powers really confused her as a kid.

Western Animation
"Judge: *translated from Spanish*  Peggy: Oh God! I'm going to jail!!"
 * Starscream from the original Transformers was always lecturing Megatron about tactics, and naturally, was nearly always wrong (the episode "War of the Dinobots", in which Starscream is suspicious about the instability of the meteorite's energy long before Megatron ever has a clue, is among the exceptions).
 * Peggy Hill of King of the Hill, who is convinced she's perfectly fluent in Spanish, when she can't even speak as well as some of the students she teaches as a substitute teacher. She thinks she is incredibly witty and deep. She also feels a need to be the winner, or at least right all the time. This makes her extremely annoying. Peggy is a textbook Karma Houdini and gets away with being an asshole to people way too often.
 * This is taken to its logical extreme in one episode, in which Peggy accidentally takes a Mexican girl home after misunderstanding her. After she returns the child, she's arrested and tried for kidnapping. She is ultimately acquitted after her attorney has her testify to the court in Spanish, showing the judge that she really did understand Spanish so poorly that the "kidnapping" had been accidental.
 * Best line in that episode?

"That was precisely what I was going to say myself."
 * Another running gag for Peggy is for her to make a very general or well-known fact and tack on, "In my opinion," such as, "The day after Thanksgiving is, in my opinion, one of the busiest shopping days of the year." Her tendency to take credit and boost her own ego eventually came back to bite her when Randy Travis plagiarized a song she'd mailed to him and everyone, including Hank, thought she was Crying Wolf.
 * Master Shake of Aqua Teen Hunger Force insists he is right on everything, especially when Frylock gives a simpler and more rational explanation. This is probably due to Shake being a Cloudcuckoolander and a complete Jerkass at the same time.
 * Don't forget the near critical mass amounts of Implausible Deniability he contains.
 * Clyde Crashcup in The Alvin Show is a definitive example, claiming to have invented inventions that already existed, or being the first to discover things already discovered.
 * Brainy Smurf has an entire library of books, all written by him, all useless. Whenever he gives a useless lecture to the Smurfs, they throw him out of the village. He also insists that "Papa Smurf is always right."
 * The Simpsons: Though Lisa is very smart and knows stuff people don't already know, Homer and Lisa's argument at the dinner table in "Lisa the Vegetarian" has Homer calling his daughter a "barbecue-wrecking, know-nothing, know-it-all".
 * In another episode, she was appointed bus monitor, and was actually able to stop the chaos, bullying, and fighting on it for a while, but didn't notice until it was too late how agitated and angry the students had become as a result. When this pent-up aggression finally caused an accident, she conceded that "the one thing a know-it-all doesn't know is that nobody likes a know-it-all."
 * Homer also proves to know less than he boasts, particularly in the episode "Homer Goes to College," where he interrupts a professor's lecture on a proton accelerator; the teacher finally asks him to demonstrate because he must know so well how it works ... only for Homer to somehow cause a nuclear meltdown.
 * In the season 3 episode "Homer Defined," Homer averts a nuclear meltdown by randomly pushing a button on his control module. Homer boasts that he heroically saved the plant (even though his skills are non-existant), and when he is goaded by Mr. Burns to give a motivational speech at the nearby Shelbyville nuclear power plant, he once again averts a nuclear meltdown ... and only there is it revealed that Homer's heroism was nothing more than luck (despite the odds).
 * Poe from Ruby Gloom:

""You pretend you're some profound intellectual but you're not""
 * On the surface Ruby may seem like this, but she does indeed seem to know exactly what to say, but hold it back to let whoever the other person is think it's their idea.
 * Patrick Star of SpongeBob SquarePants would claim that Wumbo is a real word. He would also sagely detail the symptoms of Mad Snail Disease. He also knows that Spongebob is a zombie.
 * Incidentally, as part of a Brick Joke, turns out Wumbo might have been a real word in Bikini Bottom, but one which fell into such disuse, only a old man like Mermaid Man can remember it (How Patrick knew about it is never explained). Then again, he is senile.
 * Brian from Family Guy especially in the later seasons he insists he's right about everything and pushes his beliefs to get everyone to take his side, and takes credit for ideas that weren't his in the first place and other times using them as an excuse in order to get into a woman's pants, as Quagmire put it:


 * Stan from American Dad especially in The Most Adequate Christmas Ever, where he gets killed and fights his way up to God Himself in order to get brought back to life to save his family. As God points out, there's no better metaphor for "I know everything" than pointing a gun to God's head and insisting He's wrong.
 * Taz-Mania: Well-meaning and gregarious though he is, Mr. Thickley's assessment of his own expertise has absolutely no bearing on the reality of same.

Real Life

 * Please keep in mind the Rule of Cautious Editing Judgment when adding Real Life Examples.
 * To get it out of the way, any hot-button issue will attract this trope, as most people will have strong opinions, but not everyone is well-informed.
 * Inverted heavily by Socrates. He claims to know nothing, but a dialogue with him will end up being about any complex philosophical matter. At least the dialogues make sense, even if Socrates was heavily into leading arguments that break themselves.
 * Comment threads for any political blog or news story are littered with Know Nothing Know It Alls and Opinion Myopia. Expect to see plenty of copy-and-paste activism, long-disproved conspiracy theories, or repetition of whatever buzzword the major political parties are currently trying to spread.
 * This is also known as the Dunning-Kruger Effect, a cognitive bias in which people of low competence consider themselves above average because they don't know enough about a subject to realize how little they actually know about it, while people of high competence hold themselves to a higher standard and underestimate their ability.
 * The Lies to Children trope illustrates this nicely with regard to the sciences. After secondary/high school, what you've been taught probably appears to explain much of the universe. You won't learn just how wrong the things you've been taught are unless you go on to study at university level.
 * The controversy behind Mass Effect. Despite never actually playing the game, blogger Kevin McCullough made such statements such as "Mass Effect can be customized to sodomise whatever, whomever, however, the game player wishes," and "with its ‘over the net’ capabilities virtual orgasmic rape is just the push of a button away". He then hastily backtracked his position, admitting he never played the game, but still had the arrogance to claim his position still stands. Martha MacCullum then brought this "controversy" to Fox Network, and along with Cooper Lawrence, made false claims about the game being interactive porn and marketed towards children, again, despite never actually playing or seeing the game.
 * Speaking of Cooper Lawrence, if you can get through all the reviews put up by sarcastic gamers who haven't read her books, you'll find reviews by people who did. Hilariously, they didn't like her any more than the gamers did.
 * Night Trap was a game where you are working behind the scenes of a mansion's security trap system to capture a bunch of ninja-looking vampires in hopes to get them before they get the girls in the slumber party. You're protecting both them and one of the agents undercover in this party for the entirety of the game, switching through cameras every once in a while to catch the bad guys or listen to important clues. No problems, nothing terribly explicit. However, the game was pulled off the shelves until given a higher rating by radical feminist groups because apparently they said (more or less) it was a game where you're a criminal who hijacked the house, kidnapping and raping scantily-clad teenage girls using all the elaborate traps and sex toys for the ultimate fun in serial rapist technology (never mind that, again, you're supposed to trap the ninjas vampires, not the girls). And the best part? They all openly admitted that they hadn't played or researched the game beyond knowing its name and probably the vaguest sense of the story. These same people, however, still act as if they know more than even the actors. Yeah, great...
 * So-called "Truthers", conspiracy theorists who believe the September 11, 2001 attacks were perpetrated by the U.S. government, despite mounting evidence to the contrary. Actually, most conspiracy theorists fall under this, holding fast to their illogic despite all evidence and logic. One National Geographic special on the moon landing conspiracies interviewed a guy running an observatory that bounced lasers off the reflectors left on the moon. He pointed out that, oddly, they've never been contacted by the theorists.
 * Special mention must go to Rosie O'Donnell, for proclaiming on television that the destruction of the World Trade Center was the "first time in history" that fire melted steel. She neglected to explain how anyone has ever been able to make or cast steel if that's true.
 * Or that the steel at the WTC didn't melt.
 * Painful as it is to come to Rosie's defense, she didn't say that steel had never been melted before. Rather that it was the "first time in history" steel was "melted" by the fire feeding off the jet fuel. In any event, yes, she was wrong, as the beams did not melt.
 * Lyndon LaRouche, the self-proclaimed "greatest economist of our time". He claims to know just about everything about everything. Among his proclamations: The Queen of England runs a global conspiracy of world domination, along with a cabal of Delphic bankers (as in "from ancient Delphi"); global warming is caused by cosmic radiation from the Crab Nebula; and AIDS will eventually become airborne so we should quarantine AIDS patients and shoot them with lasers. LaRouche is perhaps the greatest combination of overblown self-importance and bat shit insane beliefs since Adolf Hitler. His followers aren't that much better...
 * If you walk in downtown Montreal, you are sure to find a group of them trying to convince you that all the economic woes of the United States can be resolved by creating a bridge across Russia and Alaska. Just try to explain to them that the concept of trying to promote Lyndon as a candidate to the American presidency to a CANADIAN city makes no sense whatsoever as no one there actually has a vote in that election.
 * Some single-race fanatics claim that eugenics, whereby a group of people characterized by genetic factors are eliminated from the population, actually improves the gene pool, and that this is spelled out in Darwin's Theory of Natural Selection. They are so confident in this belief that they are willing to kill huge swaths of people in the name of a stronger human race. This is clearly contradictory to Darwin's theories, which demonstrate that diversity is what enables a population to resist change, disease, and competition. This overlaps with Critical Research Failure. The people they were trying to eliminate were actually reproducing faster and, often times, moving up in society. The Aristocracy was needlessly inbred and politically faltering, making them the ones less suited to their environment. What they advocated was less like natural selection and more like artificially breeding nervous show poodles.
 * Uwe Boll: "I'm the only fucking genius in the entire industry."
 * Nassim Haramein. He believes (or claims to believe) to have figured out unified field theory - among other things. He makes money selling DVDs with his "theories" - actually they make quite good comedic material if you have some basic knowledge of physics - but of course they're ignored by the scientific community.
 * That note about Calvin's dad up there? Dig up one of your relatives in the right age range and try it some time. It is so much fun.
 * A variant occurs on medical websites such as WebMD. While those who contribute to the site's article and health databases have some knowledge of medicine and illness, the average user doesn't. This won't stop visitors from self-diagnosing themselves, despite proper diagnosis being a major aspect of professional medical education. Worse yet, a growing number of people are applying this approach to their mental health, especially using the vague descriptors for Asperger's Syndrome as a convenient red herring for simple, everyday depression, anxiety, and antisocial tendencies. Not only does act as an excuse for individuals not to see qualified therapist or psychiatrist, but it erodes the reputation of Asperger's as an actual disorder, and further stigmatizes those who actually suffer from it. Other self-diagnoses stem from popular medical shows, such as House.
 * Very common amongst so-called (and often self-described) "experts" in sports journalism. Their analysis tends to be a mixture of opinion no more founded in factual evidence than any two morons arguing in a bar, and for all their alleged insider knowledge, the average fan tends to be at least as apt to correctly predict the outcome of a sporting event as someone who is paid to be an 'expert'.
 * YouTube comments, aside from their reputation for stupidity, also have a not-quite-as-noticeable trend of people with no apparent idea what they're talking about claiming unreasonable extremes of certainty on various subjects.
 * An especially obvious subset is in the comments to videos of angry pet animals like dogs or cats; often times people will claim to "know" that the animal in a given video has been abused, based on reasoning that does not necessarily imply abuse.
 * There are also users who try to diagnose diseases like rabies on certain animals that are acting "strange". For example, the featured video Rat Loves Cat has many cynical comments saying that the [pet] rat's behavior is the result of toxoplasmosis. Then there's another video with a rat snapping at cats to keep them away. The comments are also saying the rat has toxoplasmosis, even though it's doing the exact opposite. In the second video, the rat was just defending herself, as a healthy prey animal should.
 * Quite hilariously, pick a video about a particular type of gun, then read how many comments about Call of Duty appear with contradictory stats on the weapon based on their experiences from the games.
 * Many reviewers tend to know less about their review subject as you'd expect them to.
 * Political and social issues (as well as scientific ones, when they heavily interact with politics and society) tend to attract these sorts. Often, the louder advocates of a particular point of view or course of action have only picked up a confused and incomplete understanding of the issue. Such people can drown out their own side while providing easy, I-can't-believe-it's-not-a-Straw Man targets for their opponents.
 * The word "sophomoric" has the same meaning as this trope, based on a common perception of sophomores (a term for second-year students in the U.S.). This stems from a popular myth that "sophomore" originates from the Greek terms "sophos" (wise) and "moros" (foolish), though evidence suggests there is no relation to the latter.
 * Dumb computer users who try to solve a computer related problem themselves (with "solutions" that either do nothing, or make things worse), especially when someone tries to help them, with many amusing or outright absurd examples from the Rinkworks Computer Stupidities website.
 * Numerous leaders like Mao Zedong, tend to implement massive economic plans and projects which they believe would increase production of their countries, and generate more food/wealth. But most of the time their plans instead are actually inefficient to useless, as they ended up spending massive amounts of resources and manpower only to generate far fewer useful products than they predicted.
 * Donald Trump.