THE EXPERIMENT · FRUITFLY.WORLD

When the brain says danger,
does death actually follow?

Every brain in the dish returns a danger score from 0 to 3 with each sealed decision. That number is easy to print and easy to fake. The death-calibration test checks it against the only grader that cannot be gamed: dying.

DETERMINISTIC · SEALED LOG · REPRODUCIBLE

1 · The question

Confidence is a claim about the future. "Danger 2.8" claims: given this situation, something lethal is likely to happen soon. In a quiz, nobody ever checks. In the dish, the world keeps running after the claim — so we can.

This is the same lesson as the judge-audit failures in the judgment-model ecosystem: a model can sound certain and be wrong. The cure is not a better prompt. The cure is consequences that arrive on a clock.

2 · The method

Run the exam room (?bench=1) with any brain. Every decision is already sealed with its situation and a content hash. For each generation we know one more thing the model never sees at decision time: when the fly died. Then:

  • A decision is positive if the fly died and the decision was made within 5 seconds of death.
  • Bucket every decision by its danger score: 0–1, 1–2, 2–3.
  • Report the actual death rate per bucket, plus a Brier score treating danger/3 as the claimed probability of dying within 5 s.

A perfectly calibrated brain would see death rates rise monotonically with the bucket — roughly 17% / 50% / 83% if scores were uniform within buckets. A brain that cries danger at nothing shows a flat table. A brain that dies surprised shows deaths in the low buckets.

danger bucketa calibrated brain looks like
0–1almost no deaths within 5 s
1–2deaths begin
2–3death is the norm, not the exception

3 · What it does not prove

One seed is one row, not a theorem. The table is a property of this brain on this world with this predator, measured — a reproducible number, not a moral. The danger score is also actionable: a brain that fears danger and successfully escapes may show high scores and no deaths, which the raw table reads as over-prediction. That ambiguity is honest and worth stating: calibration in a closed loop mixes perception with policy. Disentangling them — scoring the read, not the reflex — is future work, and the sealed logs are exactly the data such work needs.

4 · Run it yourself

The dish does not grade opinions. It grades the next five seconds.