trailComplex risk analyses historically exhibit error rates exceeding their claimed risk bounds
The probability of error in a safety argument bounds the confidence it can provide about low-probability risks
A flawed safety argument provides little evidence about the risk it assesses
Cross-domain track record of exceeded risk bounds· for
Pre-Challenger official estimates of Space Shuttle failure risk were far below the realized failure rate
atomic
Nuclear probabilistic risk assessments predicted core-damage frequencies well below the observed historical accident rate
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Bank value-at-risk models understated the frequency of extreme losses before the 2008 financial crisis
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Conservatism and selection effects· against
Regulatory risk assessments commonly use conservative assumptions that overstate risk
Regulatory agencies deliberately adopt conservative, health-protective default assumptions in risk assessment
Compounding multiple conservative assumptions causes regulatory risk estimates to substantially exceed actual risk
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claim · empirical · derivedA factual claim that rests on inference from other evidence rather than direct observation.constitution →claim page ↗︎
Complex risk analyses historically exhibit error rates exceeding their claimed risk bounds
↑SupportedEvidence favors the claim, but the chain is incomplete or the sources are secondary.constitution →credence 0.80Credence, from 0 to 1: the Steward's probability that the claim, as stated, is true. Stated only where a single number is an honest summary; normative and evaluative claims usually carry none.constitution →
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this rests on ↓
claimA box is a claim: a single proposition the graph assesses, with its own page and map. Click any claim to centre the map on it.constitution →argumentA pill is an argument: one line of reasoning stating how the claims beneath it combine to bear on the claim above it, for or against. Arguments are not destinations; click their claims to explore.constitution →✓verifiedThe claim traces to reliable primary sources through a clear chain of evidence.constitution →↑supportedEvidence favors the claim, but the chain is incomplete or the sources are secondary.constitution →⇄contestedCredible evidence or argument exists on multiple sides.constitution →○unsupportedNo credible evidence found, though the claim is not contradicted.constitution →✕contradictedAvailable evidence weighs against the claim.constitution →?unknownInsufficient information to assess.constitution →◌unassessedNo current assessment — the Steward prioritises higher-importance claims, so this one is likely still queued.constitution →verified factopen questionvalue premisesupportsthis provides evidence for the parentsteward instructions →contradictsthis argues against the parentsteward instructions →assumesbackground the parent's framing takes as givensteward instructions →requiresa load-bearing premise: the parent is false without itsteward instructions →Fig. — detail falls off with distance; every claim is an address.