Time and Fragility

The Lindy effect, named after a New York deli, observes that for non-perishable things, the longer they have already existed, the longer they are likely to continue. A book that has survived two thousand years is a better bet to survive two thousand more than a book that came out last year. A technology, an institution, a recipe, a piece of advice — the things that have survived have been tested by time, while the recent things are mostly waiting to be filtered out.

Taleb uses the Lindy effect as a heuristic for evaluating risk. New things look exciting and are often fragile in ways their newness obscures. Old things look boring and have already been pressure-tested against many of the failure modes the new things will eventually encounter.

The implication is to weight your bets toward time-tested options whenever the choice is available. Old foods, old exercises, old books, old institutions, old crafts — these are antifragile by virtue of accumulated stress they have already survived. The novel alternative may turn out to be better, but the prior probability is against it.

The practical move is to be slow to abandon the time-tested in favor of the novel. The new thing might be the genuine improvement; it is more likely to be the failure that has not yet had time to reveal itself. The Lindy effect is a useful filter on the firehose of modernity.

The Lindy effect, named for the New York deli where actors observed the pattern, holds that for non-perishable things — ideas, books, technologies, institutions, recipes, proverbs — every additional year of survival raises the expected number of years still to come, because what has already endured has been filtered by the stressors that destroyed its weaker peers. A text that has lasted two millennia is a far better bet to last another two than a bestseller published last year, most of which is noise awaiting its turn through the filter. Taleb turns this into a practical heuristic: prefer the time-tested to the novel and theoretical, because age is evidence of robustness that no forecast can supply. He attacks 'neomania,' the modern infatuation with the new, as actively fragilizing — we adopt untested technologies and ideas at the expense of practices that have already proven their durability, mistaking recency for progress. The future, he argues, will consist mostly of the old surviving rather than the new arriving; the technologies and customs that persist decades hence are largely the ones already with us now. Time is the ultimate via negativa, quietly subtracting the fragile and leaving the antifragile standing as the safest guide to what is worth keeping.