It is human nature to project the past into the future. Philosophers tell us so. Florentine scribe Niccolò Machiavelli depicted adapting to changing surroundings as the foremost, and hardest, task of statesmen. For gadfly Nassim Nicholas Taleb, humanity is vulnerable to “black swans” — highly improbable events entailing mammoth consequences — precisely because people think in linear terms. What happened before, assume ordinary folk, will carry on into the indefinite future along more or less straight trend lines.

Except when it doesn’t: Then people have trouble coping. Better to play “What if?” beforehand than be caught flat-footed when the highly improbable …