“Some things benefit from shocks; they thrive and grow when exposed to volatility, randomness, disorder, and stressors and love adventure, risk, and uncertainty. Yet, in spite of the ubiquity of the phenomenon, there is no word for the exact opposite of fragile. Let us call it antifragile. Antifragility is beyond resilience or robustness. The resilient resists shocks and stays the same; the antifragile gets better.”

Another way to formulate it is: anything that has more upside than downside from random events shocks. An egg will not benefit from having a 5lb weight put on it, but your body can become stronger through similar stresses.

This builds on the arguments in Black Swan. When there’s a Black Swan event, the Antifragile can thrive. But the fragile will frequently perish. Put another way, the Antifragile can benefit from positive black swans.

“Fragility implies more to lose than to gain, equals more downside than upside, equals unfavorable asymmetry.”

“Antifragility implies more to gain than to lose, equals more upside than downside, equals favorable asymmetry.”