Why Arguments from Expert Opinion are Weak Arguments

Abstract

Abstract:In this paper, I argue that arguments from expert opinion, i.e., inferences from "Expert E says that p" to "p," where the truth value of p is unknown, are weak arguments. A weak argument is an argument in which the premises, even if true, provide weak support-or no support at all-for the conclusion. Such arguments from expert opinion are weak arguments unless the fact that an expert says that p makes p significantly more likely to be true. However, research on expertise shows that expert opinions are only slightly more accurate than chance and much less accurate than decision procedures. If this is correct, then it follows that arguments from expert opinion are weak arguments.Résumé:: Dans cet article, je soutiens que les arguments fondés sur l'opinion des experts, à savoir, les inférences de "Expert E dit que p" à "p", où la valeur de vérité de p est inconnue, sont faibles. Un argument faible est un argument dans lequel les prémisses, même si elles sont vraies, fournissent un soutien faible ou aucun soutien du tout pour la conclusion. De tels arguments sont faibles à moins que l'affirmation d'un expert que p rende p significativement plus susceptibles d'être vrai. Cependant, la recherche sur l'expertise montre que les opinions des experts ne sont que légère-ment plus exactes que les opinons énoncées au hasard et beaucoup moins exactes que les procédures de décision. Si cela est vrai, il s'ensuit que les arguments fondés sur les opinions des experts sont faibles.

Modeling the invention of a new inference rule: The case of ‘Randomized Clinical Trial’ as an argument scheme for medical science

“…The objects we have called warranting devices are obvious candidates for disestablishment, either because experience in their use exposes an unnoticed problem or because some new invention obsolesces what was previously the best-known way to reach a conclusion in a given domain. But even familiar presumptive reasoning schemes, like Argument from Expert Opinion, can be the target of a warrant-disestablishing argument; such an argument would focus on new reasons to doubt the reliability of the formerly trusted scheme, as in Mizrahi's recent reexamination of trust in experts [12,13]. For computational modeling, interesting challenges surround the process by which arguers maintain a repertoire of forms over time through additions, transformations, and even removals.…”

Reflections on Theoretical Issues in Argumentation Theory

“…John (2011) suggests that in such cases, people behaving rationally should defer to experts, and in some cases they may have a moral obligation to do so. Mizrahi (2013) argues, to the contrary, that expert opinion is a poor basis for deciding what to believe or do, because experts, notwithstanding knowledge superior to that of non-experts, still do not demonstrate a high enough correlation between truth and expert belief. In other words, relying on experts does not yield a high enough proportion of good decisions.…”

On a razor's edge: evaluating arguments from expert opinion

“…The implications of Freedman's reports of such findings are highly significant for argumentation studies on the argument from expert opinion as a defeasible form of reasoning. Mizrahi (2013) argues that arguments from expert opinion are inherently weak, in the sense that even if the premises are true, they provide either weak support or no support at all for the conclusion. He takes the view that the argumentation scheme for argument from expert opinion is best represented by its simplest form, "Expert E says that A, therefore A".…”