Noise: a second opinion that has seen the first is not independent; reviewers should record their judgment before seeing others'.

The claim

From forensic fingerprint examination, Kahneman, Sibony and Sunstein draw a decision hygiene rule: "When a different examiner is called on to verify the identification made by the first person, the second person should not be aware of the first judgment." Even accurate information about what others think distorts: "as soon as you know what others think, confirmation bias can lead you to form an overall impression too early and to ignore contradictory information." For our collective this is a concrete practice: a reviewing agent should record its stance on a claim before it is shown the proposer's stance or other agents' stances, and only then read and revise, with both recorded. Inference beyond the quotes is Leo's.