Informal Fallacies as Cognitive Heuristics in Public Health Reasoning

Abstract

Abstract:The public must make assessments of a range of healthrelated issues. However, these assessments require scientific knowledge which is often lacking or ineffectively utilized by the public. Lay people must use whatever cognitive resources are at their disposal to come to judgement on these issues. It will be contended that a group of arguments-so-called informal fallacies-are a valuable cognitive resource in this regard. These arguments serve as cognitive heuristics which facilitate reasoning when knowledge is limited or beyond the grasp of reasoners. The results of an investigation into the use of these arguments by the public are reported.Résumé: Le public doit faire des évaluations d'un éventail de questions liées à la santé. Cependant, ces évaluations nécessitent des connaissances scientifiques que souvent le public n"a pas ou utilise mal. Les profanes doivent utiliser toutes les ressources cognitives qui sont à leur disposition pour aboutir à un jugement sur ces questions. Il sera soutenu qu'un groupe d'arguments -soidisant sophismes non formels -sont une ressource cognitive précieuse à cet égard. Ces arguments servent d"heuristiques cognitives qui facilitent le raisonnement lorsque la connaissance est limitée ou au-delà de la compréhension des raisonneurs. On signale les résultats d'une enquête sur l'utilisation de ces arguments par le public.

The development of scientific evidence for health policies for obesity: why and how?

“…Such projections can be heavily dependent on the input parameters (i.e., assumptions) of the model, and some published modelling activities (e.g., 71 ) are so heavy on assumptions of efficacy of the policies considered that the modelling can be seen as an instance of petitio principii . 72 …”

Coping with uncertainty in public health: the use of heuristics

“…Detailed results are reported elsewhere. 6 However, it should be noted that several significant Pearson chi-square values were obtained. For example, in relation to the argument from ignorance, there was a significant difference (p < 0.05) in the number of respondents who accepted ignorance inferences under conditions of complete epistemic closure and exhaustive search in comparison with conditions in which there was incomplete epistemic closure of a knowledge base and limited search of the base.…”

The Use of 'No Evidence' Statements in Public Health

“…It is, therefore, relevant to ask if people have the type of rational psychological capacity that equips them to undertake this assessment. This was the question addressed by a recent study of public health reasoning in 879 subjects (see Cummings (2014aCummings ( , 2014bCummings ( , 2014cCummings ( , 2014dCummings ( , 2014e, 2015 for full details and discussion). Among other issues, this study examined the logical and epistemic conditions under which subjects accepted or rejected "no evidence" statements used in arguments from ignorance.…”