trailSafety arguments with minor flaws often remain approximately correct
A flawed safety argument provides little evidence about the risk it assesses
Residual assurance deficits in a safety case can be acceptable when compensated by other arguments and evidence
atomic
In adversarial settings, small flaws in a safety argument can be exploited into complete failure
A single overlooked vulnerability can compromise the security of an entire system
Optimizing adversaries systematically search for and exploit the weakest point of a system
Defense in depth prevents a single exploited flaw from causing complete system failure
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
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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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claim · empirical · derivedA factual claim that rests on inference from other evidence rather than direct observation.constitution →claim page ↗︎
Safety arguments with minor flaws often remain approximately correct
↑SupportedEvidence favors the claim, but the chain is incomplete or the sources are secondary.constitution →credence 0.72Credence, 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 →
1depended on by
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. Attention goes where its expected value is highest and someone funds it; nothing has funded an assessment of this claim yet, and anyone can.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.