To What Extent Do Pragmatic Reasoning Schemas Affect Performance on Wason's Selection Task?

Abstract

Cheng and Holyoak's (1985) most persuasive evidence for pragmatic reasoning schema theory has been the finding that an abstract permission version of Wason's selection task yields higher rates of solution than a nonpragmatic control. Experiment 1 presented two problem sets, one modelled after Cheng and Holyoak's abstract permission problem, which is relativley rich in extraneous features, and one after Wason's, relatively impoverished, standard problem. Each problem set varied type of rule (permission, obligation, or nonpragmatic) and task type (to reason from or about a rule). Results revealed that enriched problems were solved more often than impoverished ones, that reasoning-from problems were solved more often than reasoning-about problems, and that there was a beneficial interaction between enriching features and the permission rule. Experiment 2 demonstrated that although explicit negatives were crucial for solution of reasoning-from permission problems, they played no role in solution of enriched nonpragmatic-rule problems. Experiment 3 provided a replication of the enriched reasoning-from permission problem, again revealed no beneficial effect for obligation-rule problems, and further revealed no influence of instructions to provide brief written justifications. We argue that the results show that the scope of pragmatic reasoning schema theory needs to be narrowed, that although a permission rule does have an effect, an obligation rule does not, and that some beneficial task features are independent of anything explained by pragmatic reasoning schema theory.