The one-sentence summary

Ignore the experts, stop trying to predict everything, and embrace uncertainty


  • SWANEverything is essentially random. Black Swans (unpredictable events) disprove everything we think we know from time to time. Everyone assumed all swans were white until overseas travel revealed black ones – thousands of instances of one thing does not disprove the possibility of another. A turkey is fed for 1,000 days before Christmas, assuming all is fine – then it is killed. The highly expected not happening is also a Black Swan.
  • Their impact is huge, they are near impossible to predict, and yet afterwards we always try to rationalise them – an essentially pointless exercise.
  • Ignore the experts, stop trying to predict everything and embrace uncertainty.
  • It is easier to predict how an ice cube would melt into a puddle than guess the shape of an ice cube by looking at a puddle.


  • Umberto Eco’s Antilibrary: he has 30,000 books. It’s what you haven’t read, what you do not know, that makes the difference.
  • Mediocristan is a land where everything is averaged and so unhelpful to the point of meaninglessness. Extremistan is where all the learning is.
  • We can learn from some important lessons:

We focus on small parts of what we know and use them to project what we don’t (wrongly)

We use narrative fallacy (stories) to fool ourselves with reasons that aren’t there

We behave as if Black Swans don’t exist – they clearly do

What we see is not necessarily all there is

Variability matters: “Don’t cross a river if it is four feet deep on average.”


  • The book is quite long and highly technical – it is not for the faint-hearted.
  • The author often veers off into anecdote.
  • He quite enjoys being obscure or obtuse.
  • You cannot approach this book like a dip-in textbook.