A field guide to the ways reasoning breaks
Crowds and prestige
Also called Argumentum ad verecundiam
Citing an authority as proof when the authority is outside their field, is not a consensus, or gives no reasons.
A physicist said this diet works, so it does.
Check whether the expertise matches the claim, and ask for the reasoning behind the verdict.
Known in Latin as argumentum ad verecundiam, 'argument from modesty' — the deference we owe our betters, turned into evidence. John Locke gave it the first named treatment in his Essay Concerning Human Understanding in 1690, as one of four moves people make instead of reasoning.
A celebrated novelist posts that a new supplement cured her fatigue, and her fans order it before reading a single trial.
A Nobel laureate in economics endorses a foreign policy position on television, and interviewers treat his word as the last one.
The CEO is convinced the rebrand is right, and since she built the company, the team drops its objections without hearing her case.
A football manager is quoted explaining why a city should adopt his favourite tax scheme, and the clip circulates as if it were analysis.