trailSARS-CoV-2 has a laboratory origin
SARS-CoV-2 originated through zoonotic spillover at the Huanan Seafood Market in Wuhan
Laboratory-origin case· for
The furin cleavage site in SARS-CoV-2 is evidence of laboratory engineering
The furin cleavage site is absent from the closest known natural relatives of SARS-CoV-2
The furin cleavage site in SARS-CoV-2 uses an arginine codon (CGG) uncommon in sarbecoviruses
The DEFUSE proposal described inserting furin cleavage sites into SARS-related coronaviruses
Furin cleavage sites occur naturally in other coronaviruses
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The WIV possessed or could have engineered a close progenitor of SARS-CoV-2
The WIV possessed or had access to a bat coronavirus sufficiently similar to SARS-CoV-2 to serve as an engineering backbone
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The WIV had the technical capability to engineer a SARS-CoV-2-like coronavirus
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No natural progenitor or intermediate animal host of SARS-CoV-2 has been identified
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COVID-19 cases occurred before the Huanan Market cluster began
Epidemiological zoonotic case· against
Early COVID-19 cases cluster spatially around the Huanan Seafood Wholesale Market
Lineage distribution patterns indicate two independent spillover events at the Huanan Market
Two basal SARS-CoV-2 lineages are statistically improbable under a single spillover event
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Lineage A was present at the Huanan Seafood Market
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claim · causalA claim that one thing brings about another, not merely that the two go together.constitution →claim page ↗︎
SARS-CoV-2 has a laboratory origin
↓DoubtfulThe evidence weighs against the claim, but the examination is incomplete or the evidence is indirect.constitution →credence 0.20Credence, 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 →quantityA box with a rule beneath its text is a quantity: a value the graph estimates rather than a proposition it affirms or denies. Its estimate stands where a claim's status would.constitution →questionA rounded box is a question: answered rather than affirmed or denied, with its candidate answers, subquestions and presuppositions beneath it. Its mark says how well answered it is.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. Click one to see its reasoning and open its page.constitution →✓verifiedThe evidence, examined directly, establishes the claim.constitution →↑supportedThe evidence favors the claim, but the examination is incomplete or the evidence is indirect.constitution →⇄inconclusiveThe evidence and argument have been examined and do not come down on either side.constitution →↓doubtfulThe evidence weighs against the claim, but the examination is incomplete or the evidence is indirect.constitution →✕contradictedThe evidence, examined directly, 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 factunsettledvalue premisetheoremprizeA double ring marks a claim with a live prize: an amount in owls offered for a machine-checked proof or disproof of its published formal statement. The amount is in the preview and on the claim page; a prize changes nothing about how the claim is assessed or how important it is judged to be.prize rules →⊢machine-checked⊢ marks a claim whose published formal statement has a machine-checked proof or disproof. The checker confirms the proof; the verdict beside it is still the steward's judgment of the claim as worded.prize rules →supportsthis 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 →answersa candidate answer to the questionconstitution →Fig. Detail falls off with distance; every claim is an address.