Black Swan

A rare, unpredictable event with severe consequences.

A black swan, popularized by Nassim Taleb, is a highly improbable event that is impossible to predict, carries massive impact, and is rationalized as obvious in hindsight. Examples include the 2008 crash and the pandemic. The concept warns against over-reliance on models.

The pandemic was a black swan, unforeseen yet devastating and obvious only in hindsight.