0:00 The official cure for the Dancing Plague of 1518 was… more dancing.0:05 The city council of Strasbourg, faced with hundreds of people dancing uncontrollably in the streets, literally hired musicians and built a stage to help them dance it out.0:17 In episode seventy-four we talked about Project A119, the secret plan to nuke the moon purely for psychological effect.0:26 Well, this is a story about a psychological effect so powerful it didn't need a bomb — it just needed a single person to start moving.0:36 It began on July fourteenth, 1518.0:39 A woman named Frau Troffea stepped out of her house onto a cobblestone street and just… started dancing.0:47 There was no music.0:48 No festival.0:49 She just danced, silently, for hours.0:52 Then for days.0:53 Within a week, her husband and more than thirty others had joined her, mimicking her movements.1:00 By August, somewhere between fifty and FOUR HUNDRED people were dancing.1:05 And this wasn't a party.1:07 People were collapsing from sheer exhaustion.1:11 They were having strokes, heart attacks.1:14 Some danced until they literally died.1:17 The city authorities were panicked.1:19 Their physicians diagnosed the cause as "overheated blood," and their prescription was that the afflicted had to dance themselves free of it.1:30 So they cleared out guild halls, set up a stage in the grain market, and brought in pipes and drums.1:37 They tried to organize the chaos, and in doing so, they just poured gasoline on the fire.1:44 The music seemed to encourage even MORE people to join in.1:48 So what in the world was happening?1:51 Where have we seen this before?1:53 The first theory people usually reach for is ergotism — poisoning from a hallucinogenic fungus that grows on rye bread.2:02 It causes spasms and hallucinations.2:05 But here's where that analogy breaks down.2:08 Ergot poisoning also severely restricts blood flow to your limbs.2:13 You wouldn't be able to dance for a week; you'd be lucky to stand.2:18 The symptoms just don't line up.2:20 The real answer is almost stranger.2:23 The leading theory today is Mass Psychogenic Illness.2:27 You might know it by its older, more dramatic name: mass hysteria.2:32 Here's the thing.2:33 It’s a real physical sickness, with real symptoms, but with no organic cause.2:39 It’s triggered by extreme, shared psychological stress.2:43 And Strasbourg in 1518 was a pressure cooker.2:47 They were dealing with brutal famine, rampant disease — syphilis had just arrived and was terrifying — and intense, superstitious beliefs about a saint named Vitus who could supposedly inflict a dancing curse.3:02 The historian John Waller said the dancers’ minds were "tossed about on the violent seas of their deepest fears." They were so convinced they could be cursed to dance, that under immense stress, their bodies simply… obeyed.3:19 It was a nocebo effect on a massive scale.3:22 The belief in the sickness BECAME the sickness.3:26 We see this pattern, in miniature, even today.3:29 Think of those stories about a mysterious twitching illness spreading through a high school, with no biological agent ever found.3:39 Or a whole office getting headaches at the same time.3:43 The brain, under stress, can create physical reality.3:47 The dancing was real.3:48 The suffering was real.3:50 The deaths were real.3:52 But the cause wasn't a poison or a germ.3:55 It was an idea.3:56 The plague finally ended in September, when the remaining dancers were taken to a mountain shrine to pray for forgiveness from Saint Vitus.4:06 And then, as mysteriously as it started, it stopped.4:10 The most terrifying part of this whole story isn't the dancing itself.4:15 It's the authorities' reaction.4:18 They saw something they couldn't explain, and their solution — their well-intentioned, logical, catastrophic solution — was to build a stage for the nightmare.4:30 It’s a brutal reminder that when we're faced with something truly new, the impulse to do something can be the most dangerous thing of all.4:40 The cure wasn't more motion.4:42 It was giving people a reason to believe the motion could finally stop.