What matters when judging intentionality - moral content or normative status? Testing the rational scientist model of the side-effect effect

Abstract

The side-effect effect (SEE) is the phenomenon whereby intentionality is more likely to be attributed to agents who bring about negatively valenced as opposed to positively valenced side-effects. According to the Rational Scientist Model (RSM; Uttich & Lombrozo, 2010) the SEE reflects the differential attribution of mental states to norm violating and norm conforming agents, with norm violating side-effects supporting stronger attributions of intentionality. The major aim of this dissertation was to test the validity of the RSM as an account of the SEE. In the first series of studies psychiatric diagnostic labels were used to manipulate the norms participants applied to agents when judging intentionality. Contrary to the predictions of the RSM, perceived intentionality remained insensitive to normative information when agents were described as having a psychiatric disorder (Experiment 1a), when agents were also described as having an organic medical disorder that affected their behaviour (Experiment 1b), when the psychiatric norms were explicitly stipulated (Experiment 1c), when a more sensitive within-subjects manipulation of psychiatric labelling was used (Experiment 2) and when participants with relative expertise in psychiatric norms were tested (Experiment 3). In a second series side-effect norm status was manipulated artificially. Despite an initial failure to find evidence for the influence of norm status (Experiment 4a), evidence that intentionality attributions were sensitive to norm status was found when an online sample of North American participants were tested (Experiment 4b) and a more sensitive intentionality response scale was employed (Experiment 5). The final study (Experiment 6) used an individual differences paradigm and found some evidence that superior theory of mind was associated with a larger SEE even after controlling for general intelligence. Taken together, the findings of the second and third experimental series provide some of the strongest extant evidence for the RSM.