What is the turkey illusion, and what does it teach about predicting the future?

A turkey is fed every day, and each day its confidence that humans mean well grows, peaking the day before it is slaughtered for Thanksgiving. Extrapolating a past trend tells you nothing about the break, because the trend depends on causes you cannot see.

* The longer the trend, the more confident the turkey, until the break *

The example comes from Nassim Taleb's The Black Swan, building on Bertrand Russell's chicken ("the man who has fed the chicken every day throughout its life at last wrings its neck instead"). From the turkey's data, every one of 1000 days confirms the model "humans feed me". Its confidence is highest exactly when it is most wrong, because the real cause of the trend, the farmer's plan, never appears in its data.

For futures thinking, this means:

• a long, stable trend is not evidence that it will continue;
• breaks come from the conditions behind the trend, so you have to ask what those conditions are and how they could change;
• methods that only extend the past (linear forecasts) are blind to exactly the events that matter most.

Go deeper:

• Wikipedia: Turkey illusion — the bias, Russell's chicken and the Thanksgiving variant.
• Wikipedia: The Black Swan (Taleb) — the book behind the turkey, on rare high-impact events.