trailA flawed safety argument provides little evidence about the risk it assesses
The probability of error in a safety argument bounds the confidence it can provide about low-probability risks
Unknown flaw undermines the chain· for
Complex risk analyses historically exhibit error rates exceeding their claimed risk bounds
Pre-Challenger official estimates of Space Shuttle failure risk were far below the realized failure rate
Nuclear probabilistic risk assessments predicted core-damage frequencies well below the observed historical accident rate
Bank value-at-risk models understated the frequency of extreme losses before the 2008 financial crisis
Regulatory risk assessments commonly use conservative assumptions that overstate risk
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Graceful degradation of arguments· against
Safety arguments with minor flaws often remain approximately correct
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Evidence assembled in a safety argument retains value even if the argument's reasoning is flawed
Operational and test data provide evidence about system risk independently of the arguments that cite them
Safety cases are prone to confirmation bias toward a predetermined conclusion of safety
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Incomplete hazard identification is a principal cause of safety assurance failures
Statistical testing alone cannot demonstrate the ultra-low failure rates required of safety-critical systems
claim · empirical · derivedA factual claim that rests on inference from other evidence rather than direct observation.constitution →claim page ↗︎
A flawed safety argument provides little evidence about the risk it assesses
⇄ContestedCredible evidence or argument exists on multiple sides.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.