concept
also: Science & Thought Experiments
Black Swan
A rare, high-impact event that's only obvious in hindsight.
Origin
Europeans assumed all swans were white until Dutch explorers found black swans in Australia in 1697 โ destroying centuries of confident induction. Nassim Nicholas Taleb's 2007 book The Black Swan made the phrase shorthand for unpredictable, outsized events (the 2008 financial crisis, 9/11, COVID-19) and the human tendency to rationalize them after the fact.
Modern usage
Standard in finance, risk management, and tech postmortems. Often misused for anything unexpected; Taleb's stricter sense reserves it for genuinely consequential surprises.
In the wild
The pandemic was the textbook black-swan event of the decade.โ finance press
Tags
risk
unpredictability