The Structure of Worry: Prediction Error in an Unknowable Future

Why do humans worry? This paper argues that worry arises from a structural mismatch: thebrain is a prediction machine operating on a fundamentally unpredictable future. The brainminimizes prediction error by generating models and testing them against outcomes. But thefuture provides no outcomes to test against—it has not yet occurred. Worry is the brain'sattempt to minimize prediction error for events that cannot yet generate error signals. Thiscreates a loop: simulate future → detect "error" (uncertainty) → simulate again → detect"error" → repeat. The loop cannot terminate because there is no actual outcome to confirm ordisconfirm predictions. Compounding this: (1) the future is structurally unknowable due toaxiom system transitions; (2) meaning is relational and observer-dependent, so "whatmatters" is constructed, not given; (3) multiple possible futures generate multiple predictionstreams that cannot be resolved. Worry is not malfunction but the predictable consequence ofprediction machinery applied to domains where prediction cannot succeed.