The Lucretius Problem

Just as any river is enormous to someone who looks at it and who, before that time, has not seen one greater. So, too, a tree or man may also appear gigantic. With all things of every kind the largest that any man has seen he imagines as prodigious, even though all of them along with heaven and earth and ocean are nothing compared to the total sum of the universal whole.

— Titus Lucretius Carus, De rerum nature (“On the Nature of Things”)

When predicting the worst (or best) case scenario, we often anchor to the last worst (or best) event in the past. We fail to incorporate that the previous worst-case scenario was even worse than the one before it.

Nassim Nicholas Taleb called this cognitive bias the Lucretius problem.

Our experiences shape our expectations, and our experiences are limited, so our expectations are inherently skewed. It’s hard to generalize outside of our training data set. Sometimes, the past is the best predictor of the future. Especially when we’re given limited information, predicting within the known range of values makes sense. But the actual worst (or best) case scenario might be beyond our wildest dreams.