The experimental philosophy of logic and formal epistemology:Conditionals

Classical logic was long believed to provide the norms of reasoning. But more recently researchers interested in the norms of reasoning have shifted their attention toward probability theory and various concepts and rules that can be defined in probabilistic terms. In philosophy, this shift gave rise to formal epistemology, while in psychology, it led to the New Paradigm psychology of reasoning. Whereas there has traditionally been a clear division of labor between philosophers and psychologists working on reasoning, the past decade has seen an increasing collaboration between philosophers and psychologists, from which an experimental philosophy of logic and formal epistemology emerged. An area in which the fruits of this collaboration have been par-ticularly in evidence is the research concerned with conditionals and conditional rea-soning. This chapter showcases contributions to this area to underline the value of the said branch of experimental philosophy more generally.</p

Structured decision-making drives guidelines panels’ recommendations ‘for’ but not ‘against’ health interventions

Background: The determinants of guideline panels’ recommendations remain uncertain. Objective: To investigate factors considered by members of 8 panels convened by the American Society of Hematology (ASH) to develop guidelines using GRADE system. Study Design and Setting: web-based survey of the participants in the ASH guidelines panels. Analysis: two level hierarchical, random-effect, multivariable regression analysis to explore the relation between GRADE and non-GRADE factors and strength of recommendations (SOR). Results: In the primary analysis, certainty in evidence [OR=1.83; (95CI% 1.45 to 2.31)], balance of benefits and harms [OR=1.49 (95CI% 1.30 to 1.69)] and variability in patients’ values and preferences [OR=1.47 (95CI% 1.15 to 1.88)] proved the strongest predictors of SOR. In a secondary analysis, certainty of evidence was associated with a strong recommendation [OR=3.60 (95% CI 2.16 to 6.00)] when panel members recommended “for” interventions but not when they made recommendations “against” [OR=0.98 (95%CI: 0.57 to 1.8)] consistent with “yes” bias. Agreement between individual members and the group in rating SOR varied (kappa ranged from -0.01 to 0.64). Conclusion: GRADE’s conceptual framework proved, in general, highly associated with SOR. Failure of certainty of evidence to be associated with SOR against an intervention, suggest the need for improvements in the process

When fast logic meets slow belief: Evidence for a parallel-processing model of belief bias.

Two experiments pitted the default-interventionist account of belief bias against a parallel-processing model. According to the former, belief bias occurs because a fast, belief-based evaluation of the conclusion pre-empts a working-memory demanding logical analysis. In contrast, according to the latter both belief-based and logic-based responding occur in parallel. Participants were given deductive reasoning problems of variable complexity and instructed to decide whether the conclusion was valid on half the trials or to decide whether the conclusion was believable on the other half. When belief and logic conflict, the default-interventionist view predicts that it should take less time to respond on the basis of belief than logic, and that the believability of a conclusion should interfere with judgments of validity, but not the reverse. The parallel-processing view predicts that beliefs should interfere with logic judgments only if the processing required to evaluate the logical structure exceeds that required to evaluate the knowledge necessary to make a belief-based judgment, and vice versa otherwise. Consistent with this latter view, for the simplest reasoning problems (modus ponens), judgments of belief resulted in lower accuracy than judgments of validity, and believability interfered more with judgments of validity than the converse. For problems of moderate complexity (modus tollens and single-model syllogisms), the interference was symmetrical, in that validity interfered with belief judgments to the same degree that believability interfered with validity judgments. For the most complex (three-term multiple-model syllogisms), conclusion believability interfered more with judgments of validity than vice versa, in spite of the significant interference from conclusion validity on judgments of belief

Slower is not always better: Response-time evidence clarifies the limited role of miserly information processing in the Cognitive Reflection Test

We report a study examining the role of `cognitive miserliness' as a determinant of poor performance on the standard three-item Cognitive Reflection Test (CRT). The cognitive miserliness hypothesis proposes that people often respond incorrectly on CRT items because of an unwillingness to go beyond default, heuristic processing and invest time and effort in analytic, reflective processing. Our analysis (N = 391) focused on people's response times to CRT items to determine whether predicted associations are evident between miserly thinking and the generation of incorrect, intuitive answers. Evidence indicated only a weak correlation between CRT response times and accuracy. Item-level analyses also failed to demonstrate predicted response time differences between correct analytic and incorrect intuitive answers for two of the three CRT items. We question whether participants who give incorrect intuitive answers on the CRT can legitimately be termed cognitive misers and whether the three CRT items measure the same general construct

On some limits of hypothetical thinking

Faced with extreme demands, hypothetical thinking runs the danger of total failure. Paradoxical propositions such as the Liar ("I am lying") provide an opportunity to test it to its limits, while the Liar's nonparadoxical counterpart, the Truthteller ("I am telling the truth"), provides a useful comparison. Two experiments are reported, one with abstract materials ("If I am a knave then I live in Emerald City") and one with belief-laden materials (a judge says: "If I am a knave then I enjoy pop music"). In both experiments, conditionals with Truthteller-type antecedents were "collapsed" to responses of conditional probability closely resembling estimates of control items. Liar-type antecedents, in contrast, dramatically weakened belief in conditionals in which they were embedded. The results are discussed in the framework of the theory of hypothetical thinking.25 page(s