Arthur: Right, but it's not your idea, because you know I gave it to you.
This is about a phenomenon of your very thought process: telling someone not to think about something will inevitably and involuntarily lead to them thinking about it. Telling yourself not to think about something may be even more futile, as by thinking about not thinking about it, you are thinking about it.
The suggestion that you should not be thinking about something is, in itself, sufficient to induce thinking about that thing. No other provocation is required—you don't have to be surrounded by elephants for the old schtick to work. For instances when people can't stop thinking about some aspect of a person because it is so very noticeable, even if they don't want to mention it due to politeness, see Ignore the Disability. When thinking about a particular action makes it more difficult than performing the action unthinkingly, you are faced with the Centipede's Dilemma. Telling someone not to do something in hopes that they will decide to go and do it is plain ol' Reverse Psychology, or one of its Sub Tropes.
This phenomenon is actually a direct result of how the human brain is wired. Neurons that are used to interpret words like "elephant" have synaptic connections to the neurons used to picture and think about the concepts those words represent; if they weren't, verbal language itself probably couldn't function.
- This idea is incorporated into the powers of Pakunoda of the Phantom Troupe in Hunter × Hunter. Her ability as a Living Lie Detector works by asking a person questions while she is physically touching them, allowing her to read their memories as they answer. Even if you know full well going in that the question she's going to ask is one you don't want to answer, you won't be able to help thinking of the answer as soon as she asks the question, giving her what she wants regardless of whether you're honest or not.
- In the card game Girl Genius: The Works, the action on the Phil Foglio card is "Do not think about a monkey."
- In Ultimate Spider-Man, Jean Grey congratulates Peter Parker on being the first man she's met in months who didn't visualize her naked. He immediately does just that. At length. (You'd think a telepath would have a better understanding of how people's minds work.)
- Buck Godot: Zap Gun for Hire has one at the end of a story where the Prime Mover tells a reporter that if she even thinks about the events that just happened (which would reignite the war they just barely prevented), her head will explode. She nervously jokes that he can't be serious; he suggests a lobotomy.
- At the climax of the Emperor Joker storyline, Superman mentions this when he finally has his Eureka Moment and realizes the "rule" that lets him defeat The Joker: Joker has his own "white elephant" — Batman, without whom he can't even define his own existence. Which means that even if he has godlike powers, Batman's really the one in charge and Joker's nothing more than an annoyance.
Superman: White elephants...the joke — "Don't think of white elephants...?" And it's all you can think of. White elephants.
Joker: How many times do I have to tell you people, that's not a joke! It's a short-term mnemonic cognition gag! Philistines, everywhere I go!
- In the Spider-Man storyline "The Ends of the Earth", this is how Spidey takes control of Sandman's form. As he explains "This I don't mind telling you. In fact, you knowing only helps. You just got pink hippo-ed, Sandy. We're transmitting images across your brainwaves, putting pictures in your head. Try not thinking about 'em!"
- In The Last Son, one of the Martian Manhunter's favorite ways to telepathically extract information from someone is to simply get right in their face and tell them not to think about what he wants to know.
- Ghostbusters (1984). The gang is on the roof facing off with Gozer, she tells them to choose her form, Venkman figures it out and tells the rest of the group to keep their minds a blank. Cue Stantz thinking about the Stay Puft Marshmallow Man. Gozer then becomes a giant Stay Puft Marshmallow Man and terrorizes the city.
- In The Good Witch's Garden, a little girl is cured of nightmares by being told that she must not, under any circumstances, dream about bunnies. Three guesses what she dreams about, and the first two don't count.
- Discussed Trope when some explanation is called for on what the titular inceptions entail.
- Mal is basically this trope made "flesh" in the dream world; because of Cobb's issues, as soon as she shows up it's very hard for him to get rid of her.
- The "don't think about elephants" bit comes up in Six Degrees Of Separation.
- In the 2010 version of The Voyage of the Dawn Treader, Lord Rhoop essentially says "Whatever you do, don't think about your greatest fear!"
- A guy has an impotence problem. One day, late at night, he's sitting in a bar, very drunk and complains about his problem. Then some sleazy guy appears and tells him: "I have some special medicine for you! It costs 1000 bucks, but it'll cure you forever! Just swallow it and wait for five minutes - but remember one thing: You mustn't think of a rhinoceros during that time, or it won't work!" Guess how it turns out.
- A man demonstrates the ability to jump off a tall building and survive, claiming that he can do so by convincing himself he is made of rubber, but then another man splats because he can't help but think of himself as a tomato at the last minute. Cue the actual punchline, from a third person: "Superman, you're a dick."
- Subverted in one of the novels featuring Tiffany Aching, where Granny Weatherwax proudly proclaims that she is "perfectly capable" of not thinking about a pink rhinoceros. Tiffany eventually twigs that this is because Granny doesn't know what a rhinoceros is.
- In the novel Sourcery, travelling inside a magic lamp being held by one of the people travelling, which is moving to its destination because the person holding it is, is possible as long as nobody thinks about the fact it really isn't. One of the characters compares it to "not thinking about purple rhinoceroses".
- In The Light Fantastic, Rincewind and Twoflower hitch a ride on a huge rock which a young druid is flying to an under-construction stone circle. Informed that the rock stays up because the druids have persuaded it to fly, and will fall if anyone's thoughts remind it that rocks can't do that, Rincewind struggles to think of rocks swooping and soaring around rather than sitting on the ground. He's miserably aware that he's not very good at it.
- There is a Russian book called The Tale of Hodja Nasreddin (the legendary Nasreddin is a mullah, but here he is described as a mischievous vagabond). In one chapter, he tells the usurer Jafar that he is a powerful (and expensive) healer, but his healing won't work if Jafar or anyone in his family thinks of the red monkey (and he describes it in excruciating detail). His clan spent much of the following night arguing about who was the first to think the forbidden thought.
- In one of Manly Wade Wellman's vignettes about Silver John (available in his story collections about the same character), the titular John massively averts this trope. Presented with a supposed magical ritual which the caster announces will only work if nobody in the audience thinks of a particular thing, John manages not to think about that thing because he focuses all his attention on memorizing every detail of the ritual. Later he reproduces the ritual, telling his audience not to think about a different thing — and it works.
- In The Dresden Files novel Ghost Story, Harry's ghost is told that he can avoid sinking through any surface he "sits" on by not thinking about it too much. Which causes him to immediately fall through the bottom of the car. He does get better at not-thinking later on.
- Near the beginning of the Lensman novel Gray Lensman, this is used to show how well-disciplined Kinnison's mind is — he is able to not think about something he saw in Helmuth's base until he's back on board the flagship. (It was a thought-triggered bomb, so if he hadn't had that mental discipline it would have ended the series early.)
- The Eyre Affair: Thursday's time travelling father shows up and tells her to tell her mother not to paint the bedroom mauve, because she does so in the future and he hates it. Thursday dutifully tells her mother, only to discover that her mother had no plans to paint it at all, let alone mauve; but after Thursday tells her not to she does.
- In The Hitchhiker's Guide to the Galaxy, the secret of flight is "throwing yourself at the ground and missing"—in other words, you have to fall and then completely forget about the fact that you're falling before you hit the ground. Then, of course, you can only keep flying as long as you keep forgetting that you should be falling. The books note how difficult this is to pull off in practice. The first time Arthur Dent flies, he's only airborne for less than a minute.
- In the Star Wars Expanded Universe, it's not unknown for Jedi to use a leading-questions variant of this trick to make it easier to get information from other people. (Jedi can read minds, but anything deeper than the surface is both difficult and possibly dangerous for both parties.) So for instance, it's hard to simply reach into a guard's mind and rip out the password to a door — but if you ask what the password is, it floats right to the top where it's easy to read.
- In The Mysterious Benedict Society, the titular society has infiltrated the Learning Institute for the Very Enligthened on Nomansen Island, in order to stop the plans of Mr. Curtain, who wants to use his devious Whisperer device to Take Over the World. As part of their spying, Reynard "Reynie" Muldoon and George "Sticky" Washington are made Messengers, which means they actually get to sit in the Whisperer across from Mr. Curtain and use it to broadcast messages, and also have it sooth their fears. Mr. Curtain has programmed the Whisperer to detect surface thoughts because he knows that fears lurk close to the surface and are easy to detect. When they take their first turns in the Whisperer, Reynie and Sticky try to hide certain stuff, as they're afraid that Mr. Curtain can detect their thoughts. It's fortunate that he can't, as they have no success in hiding them.
Reynard Muldoon, what do you fear most? Spiders, Reynie lied, trying to regain some control. Spiders made Reynie nervous, but he wasn't afraid of them. Certainly they were not what he feared most. That was something he didn't want the Whisperer to know. But responding to Reynie's involuntary answer, the Whisperer said, Don't worry. You are not alone.
- Mama Mathers in Ward exploits this with her power: if you see her and later think of her, she can read your mind. Not only that, while she's reading your mind, images of her appear in your head, so it's almost impossible to get her out. Rain Frazier tries to avoid thinking of her so she won't find out about his friends or what they know, but he fails when a friend mentions possibly being watched.
- My Name Is Earl. While Earl is in prison he takes a creative writing class, but can't think of anything to write about. His cellmate Sonny is taking the same class and tells him about his story, which involves beating up a gymnast. Earl tries to go into his imagination, but it's a White Void Room with nothing in it but him...and a gymnast. The gymnast offers to be in his story, but Earl declines because "that's Sonny's thing." Earl then spends the next 4 1/2 hours in the room, and the only thing he sees is the gymnast from Sonny's story.
- The Mentalist. Jane will often tell a suspect something like "Don't think about where you put the gun" and then watch where the suspect's eyes go, which tells him where the gun is. Although likely as not it'll be a misdirection, telling Alice this while Bob (the real killer) is in the room, so Bob will look while he thinks Jane is paying attention to Alice.
- Also invoked in Coupling as the basis to Jeff's "Giggle Loop":
Jeff: Basically, it's like a feedback loop. You're somewhere quiet. There's people. It's a, it's a solemn occasion. A wedding. No, i—it's a minute's silence for someone who's died. Minute's silence, ticking away. *tick, tock, tick, tock* The giggle loop begins. Suddenly, out of nowhere this thought comes into your head: "The worst thing I could possibly do during a minute's silence... is laugh. And as soon as you think that you almost DO laugh. Automatic reaction! But you don't, you control yourself, you're fine. *exhales* ...but then you think about how terrible it would've been if you had laughed out loud in the middle of a minute's silence. And so you nearly do it again, only this time, it's a BIGGER laugh. And then you think how AWFUL this BIGGER laugh would've been, and so you NEARLY laugh again, only this time it's a VERY big laugh. It's an ENORMOUS laugh. Let THIS bastard out, and you get whiplash! And suddenly, you're in the middle of this completely silent room, and your shoulders are going like you're drilling the road! And what do you think of this situation? Oh, dear Christ, you think it's FUNNY!
- In the Cyberax arc of Bugs, one of the good guys asks Ros not to think about elephants, to bait her away from Cyberax's thought-activated mental bomb.
- In Babylon 5, Trakis is "warned" not to think about irrelevant facts such as Adira Tyree's current whereabouts while attending a telepath-monitored negotiation. Of course, that information then appears in Trakis' surface thoughts, where Talia can perceive it without deliberately probing (that being the limit of how far she was willing to bend PsiCorps rules).
- Fawlty Towers: In "The Germans" episode Basil tells himself (and others) to not mention the the war. He fails miserably, to the point of making one of them cry, after that he does a Silly Walk Hitler impression. To be fair to him, he is badly concussed at the time; even Basil wouldn't be this terrible to his guests under normal circumstances.
Basil Fawlty:Polly, are these German too?Polly:oh yes, but I cou—Basil Fawlty:Right! Right! Here's the plan, I'll stand there and ask them if they want something to drink before the war...Before their lunch! Before their lunch! Do not mention the war!Basil Fawlty: Ah, wonderful! WUNDERBAR! Ahh! Please allow me to introduce myself, I am the owner of Fawlty Towers. And may I welcome your war... your war... you wall... you all... you all, and hope that your stay will be a happy one. Now, would you like to eat first, or would you like a drink before the war... AHH! Er... trespassers will be tied up with piano wire... SORRY, SORRY!
- Misfits: Nathan has trouble hiding his attraction to Kelly from her Mind Reading powers.
Nathan's Inner Thoughts: Don't think about shagging her. Don't think about shagging her. You're thinking about shagging her. You're an idiot.
- A The Whitest Kids U' Know sketch shows cute animals and a voiceover stating that if you think of various oddly colored animals it will die, then a second later an explosion. Until:
''"And this man will die if you think of a cheaper, more efficient way for our nation to use its national resources."*Nothing happens*"Or naked women."*BOOM*
- Defied by Dr. Carson Beckett in the first season finale of Stargate Atlantis. He interrupts somebody trying to tell him how to operate the city's control chair.
Beckett: Don't tell me what not to think about or I'll start thinking about it!
- In one The Far Side strip, a man visiting a hospital patient in a plaster cast says, "You're not itching anywhere are you? Because you can't scratch you know. Don't even think about itching, it'll drive you nuts".
- In a Garfield strip, when Jon and Garfield are at Irma's diner:
Irma: Here's your egg, hon. Whatever you do, try not to think about where it came from.(Beat)Jon: Have an egg, Garfield.Garfield: Too late. I already thought about it.
- In Portal 2, Cave Johnson describes some sort of reaction that would cause the frontal lobe of your brain to become vitrified. Of course, he points out that picturing the reaction causes it, so don't think about it.
- In Freefall, Sam gets the robots to think up a devious master plan for him this way:
Sawtooth: All we have to do is not think of a devious master plan for Sam.Qwerty: DOH!Dvorak: You didn't.Qwerty: Oh, come on! It's like being told not to think of a rhinoceros with a teacup.
- Manly Guys Doing Manly Things: Time travel technology only works if you don't think about it. Time travel veterans make a point of distracting first-timers so the trip goes smoothly.
Commander Badass: Yeah, time travel's been super stable ever since scientists figured out that th' less ya think about it th' more solid and seamless everything hooks up. S'like they say, "A watched cheetah never bevels."Jones: That is not a thing people say. What does that even mean? Literally no person has ever said that befo—[Suddenly, they're both in the future.]Commander: 'S way more efficient than saying "Don't think about time travel."
- Grrl Power combines this with some magnificent trolling; a sign in the men's shower room that reads, "Try not to think about the fact that some of the most beautiful women on Earth are showering, changing and possibly having tickle fights on the other side of this wall."
- 8-Bit Theater: Red Mage proposes a plan which requires the team to build a portable hole the size of the universe, with no materials, twice. Black Mage says it's the dumbest plan he's ever heard. Red Mage says Lets See You Do Better Black Mage says that the plan is so dumb that literally anything else he says would be better. Red Mage points out that the same plan with three universe-sized portable holes would be worse. Black Mage says he won't suggest that, then.
Red Mage: Well, go on, then. Let's hear your idea, smart guy.
Black Mage: All I can think of is the damn three hole version! Argh!
- Happens in a first season episode of Men in Black The Animated Series. K had been infiltrating an psychic alien conspiracy trying to invade earth for years by disguising himself as one of their own (who had willing let him do so because he had gone native). After explaining everything to J this happens:
K: Oh. And whatever you do, don't think about what I just told you.
J: That's the last thing you tell someone when you don't want them to think about something!
(They are then immediately caught)
- In one episode of Johnny Bravo, Johnny, inside of a dream, is on a date. After learning from the real world that anything he thinks of will happen in the dream world, his date randomly tells him to not think of her as a monster. Naturally, he has to then picture her as one, which turns her into one.
- In the Darkwing Duck episode "Heavy Mental", there's an invention that give normal people assorted Psychic Powers. However, the targeted person isn't supposed to be thinking at all while the invention is used on them, or else their head will explode. Guess how the Villain of the Week is defeated.
- Referenced in Justice League Unlimited. After the heroes pull a fast one on Granny Goodness, the mind-reading Martian Manhunter tells her to try not to think about where she's keeping her hostage. Granny cringes, and J'onn promptly gives Flash his location.