The black swan theory was developed by Nassim Taleb to describe an event that is a complete surprise, has a major impact, and after the fact is rationalized with the benefit of hindsight.

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Whether you are a devotee of the Black Swan Theory or merely another hard-boiled cynic like me, you may now be counted among those who place little comfort in years of accumulated stock market statistics.

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He calls them Black Swans, after the philosopher Karl Popper's observation that only a single black swan is required to falsify the theory that "all swans are white" even when there are thousands of white swans in evidence.

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Nassim Taleb has explained the stupidity of such false assurances and misplaced comfort in his Black Swan Theory, and I will not attempt to footnote his extensive treatise.

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But Antifragile: Things That Gain From Disorder expands on the concepts in Fooled and its follow-up The Black Swan and goes far beyond financial markets into a more general theory of randomness and volatility and their importance in life and nature.

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