Unlike a superstition, a hyperstition is a belief that is not merely self-fulfilling, but rather by believing it, the world actually does change to make it self-fulfilling. Not just a truism or something that is true by construction, but instead a feedback loop. Scott Alexander talks about "[hyperstitious slur cascades](https://astralcodexten.substack.com/p/give-up-seventy-percent-of-the-way)": believing something is a slur (or otherwise a bad word) is a hyperstition - if you and enough other people believe it's a slur, it *becomes* a slur. Then you add on an 'information cascade' - there's some threshold beyond which it "tips" into being a slur among wider and wider groups of people. He talks about "joining" the cascade at about the 70% mark; higher-disagreeability personalities like Bryan Caplan [talk about joining at 98%](https://twitter.com/bryan_caplan/status/1634230846084481028?t=8ICinQdvr337OG6xGNh67A&s=09).