Consistent with natural origin
The argument
Because linked claim and linked claim, the presence of such a site needs no laboratory to explain, and given linked claim, its imperfect form is what an unguided natural process would produce rather than a designed one — together undercutting the inference to engineering.
Does it work?
- Does it follow?
- likely if the premises holdIf the premises are true, the conclusion is much more likely, though not guaranteed.constitution →
- Do the premises hold?
- 3 not separately assessed
Granting its premises, that furin cleavage sites occur naturally in other coronaviruses, that natural recombination can generate such insertions, and that the site is suboptimal rather than idealized, the inference substantially undercuts the claim that the site is distinctive evidence of engineering: if nature readily produces such sites and this one bears no mark of design, its presence is not probative of a laboratory. This does not affirmatively establish natural origin, so the support is likely rather than certain. It rests mainly on the natural-occurrence and recombination premises; the suboptimality judgment is the more contestable of the three.
Premises
- 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 →Furin cleavage sites occur naturally in other coronaviruses
- 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 →The furin cleavage site in SARS-CoV-2 is suboptimal and not an idealized engineered sequence
- 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 →Natural recombination can generate furin cleavage site insertions in coronaviruses
Where it is made
Passages where sources make, criticize or mention this argument. They record where it appears, not how strong it is, and none has precedence over another.
No source is recorded as making it.