History Main / SharedMassHallucination

* [[http://en.wikipedia.org/wiki/Penis_panic A penis panic]] is a form of mass hysteria where groups of people suddenly become convinced that their genitals are shrinking or disappearing. Many other strange mass hysterias and hallucinations have also occurred in history, such as those documented in the book [[http://en.wikedia.org/wiki/Extraordinary_Popular_Delusions_and_the_Madness_of_Crowds Extraordinary Popular Delusions and the Madness of Crowds]].

* The ''Film/MenInBlack'' do this after using their [[LaserGuidedAmnesia neuralyzers]], which make the targets extremely susceptible to suggestions, allowing the Men in Black to craft a plausible suggestion that everybody "saw."

* [[http://en.wikipedia.org/wiki/Penis_panic A penis panic]] is a form of mass hysteria where groups of people suddenly become convinced that their genitals are shrinking or disappearing.

* After the resurrection of Jesus, Roman troops were coerced into claiming that Jesus' disciples overcame them and stole the body, despite them all having good alibis. After reports of Jesus walking and talking for a full forty days after his alleged demise, the Romans claimed that he was OnlyMostlyDead despite three days being far more than any human could survive without treatment after flagellation alone, much less [[ThereIsNoKillLikeOverkill flagellation, crucifixion, and a spear wound.]] Somewhat subverted in that Christianity eventually became the official state religion of the Roman Empire.
** Of course seeing how people who knew Jesus well took a long time to even recognize that this person even looked like their spiritual leader, it can be questioned if he was indeed the same person before and after the crucifixion.

[[ArtisticLicenseBiology Hallucinations don't work that way]], even if multiple people were exposed to the same hallucinogen, they wouldn't see the same thing. The only time it's remotely plausible is if the people were already expecting to see whatever it was they believed they saw (which, in fact, is a very large part of how StageMagic is performed) - and even then, they probably wouldn't share the particular details of the hallucination.

* The ''Film/MenInBlack'' do this after using their [[LaserGuidedAmnesia neuralyzers]], which make the targets extremely suceptible to suggestions, allowing the Men in Black to craft a plausible suggestion that everybody "saw."

* In ''Series/{{CSI}}'', Grissom refers to the alien conspiracy theorist club to having a shared mass hallucination. Of course, they saw this as a part of the evil police force working for the reptilians trying to put them down.

[[AC:Religion]]
* After the resurrection of Jesus, Roman troops were coerced into claiming that Jesus' disciples overcame them and stole the body, despite them all having good alibis. After reports of Jesus walking and talking for a full forty days after his alleged demise, the Romans claimed that he was OnlyMostlyDead despite three days being far more than any human could survive without treatment after flagellation alone, much less [[ThereIsNoKillLikeOverkill flagellation, crucifixion, and a spear wound.]] Somewhat subverted in that Christianity eventually became the official state religion of the Roman Empire.
** Of course seeing how people who knew Jesus well took long time to even recognize that this person even looked like their spiritual leader, it can be questioned if he was indeed the same person before and after the crucifixion.

* Used to explain a false Angel sighting in GlobalFrequency.

* Pretty much the idea behind ''ChaosHead'', but it runs on the idea in reverse: if you can get more than one person to see the same thing (real or not), it suddenly becomes real.

* In ''ArkhamAsylumLivingHell'', Franchise/{{Batman}} explains away the presence of demons and HellOnEarth by telling the Asylum staff that it was due to Scarecrow's fear gas. Jeremiah Arkham accepts the explanation and sends Crane to solitary confinement, much to Crane's bewilderment.

* ''The Futurological Congress'' describes drugs so effective at masking reality that the subject cannot tell which of his perceptions have been altered, and which have not. Everyone is under the influence, but the protagonist takes a drug that cancels the effect.

* ''Graveyard School'' namedrops this in one book, then immediately has it subverted. It's never made quite clear ''how'' TheMasquerade remained intact after [[spoiler:a supposedly hallucinated dinosaur ate a teacher]].

-->Two people don't share the same hallucination.
--->-'''Dr. Tom Nesbitt''', ''TheBeastFromTwentyThousandFathoms''

Hallucinations don't work that way, even if multiple people were exposed to the same hallucinogen, they wouldn't see the same thing. The only time it's remotely plausible is if the people were already expecting to see whatever it was they believed they saw (which, in fact, is a very large part of how StageMagic is performed) - and even then, they probably wouldn't share the particular details of the hallucination.

** Played even more straight today, as some rationalist skeptics hold to the theory that the sightings of Jesus after His crucifixion were some form of mass hallucination or hypnosis, though they're more likely to argue that the biblical account of Jesus's resurrection is unreliable.

* "Ghost V", a short story by RobertSheckley saw the protagonists land on a deserted planet and see mass hallucinations of the monsters they invented in their childhood. It turned out, the planet's atmosphere contained a hallucinogen that forced humans to relive their childhood fears, which became really dangerous if YourMindMakesItReal.

* In Webcomic/GirlGenius, it really was a [[http://www.girlgeniusonline.com/comic.php?date=20070129 shared mass hallucination]]. It was caused through a combination of a gas inducing a hypnotic hallucinatory state and someone yelling about the Heterodynes being back.

* In a SuzumiyaHaruhi short story, ''Snow Mountain Syndrome'', the plot of the entire story (almost a day long) was explained to the titular character as shared '''Highway Hypnosis'''. From wandering in a blizzard.

** This is also the justification for why [[spoiler: the titular box is able to kill people. It has a little bit of the gas in it, so anyone who opens it expecting to die, will.]]

* Pretty much the idea behind ChaosHead, but it runs on the idea in reverse: if you can get more than one person to see the same thing (real or not), it suddenly becomes real.
* A ''Anime/{{Pokemon}}'' episode had the police attibuting reports of an Aerodactyl attack to mass ''dreams''.

* In ''ArkhamAsylumLivingHell'', {{Batman}} explains away the presence of demons and HellOnEarth by telling the Asylum staff that it was due to Scarecrow's fear gas. Jeremiah Arkham accepts the explanation and sends Crane to solitary confinement, much to Crane's bewilderment.

** Played even more straight today, as some rationalist skeptics hold to the theory that the sightings of Jesus after His crucifixion were some form of mass hallucination or hypnosis.

* In the ''[[HitchhikersGuideToTheGalaxy Hitchhiker's]]'' novel ''So Long and Thanks for All the Fish'', soon after Arthur Dent lands to his shock on Earth, he is told that the Vogons' apparent destruction of the planet (the very premise of the series) was a CIA-induced mass hallucination. In fact, [[spoiler: Dent has landed on an Earth rebuilt by the dolphins]].

** Ofcourse seeing how people who knew Jesus well took long time to even recognise that this person even looked like their spiritual leader, it can be questioned if he was indeed the same person before and after the cruxifiction.
** Played even more straight today, as some rationalist sceptics hold to the theory that the sightings of Jesus after His crucifixion were some form of mass hallucination or hypnosis.

* After the resurrection of Jesus, Roman troops were coerced into claiming that Jesus' disciples overcame them and stole the body, despite them all having good alibis. After reports of Jesus walking and talking for a full forty days after his alleged demise, the Romans claimed that he was OnlyMostlyDead despite three days being far more than any human could survive without treatment after flagellation alone, much less [[ThereIsNoKillLikeOverkill flagellation, crucifixion, and a spear through the heart.]] Somewhat subverted in that Christianity eventually became the official state religion of the Roman Empire.