People Who Believe Implausible Claims are not Cognitive Misers: Evidence from Evaluation Tasks

Belief in epistemically implausible claims, such as climate change is a hoax and vaccines are harmful, is a pervasive problem. We test the idea that people who believe such claims possess a generally lazy thinking style (Miserly Hypothesis). Across three studies, we compared believers and non-believers of implausible claims on evidence evaluation tasks. Study 1 focused on high and low-quality forensic evidence, while Study 2 examined evaluations in a medical setting. In Study 3, we assessed the effect of time constraints on evaluations. We found little evidence for the Miserly Hypothesis; believers and non-believers did not differ in their sensitivity to high and low-quality evidence, and both groups’ evaluations were equally affected by time constraints. Believers and non-believers displayed a tendency for effortful, analytic thinking. Our findings challenge the notion that believing implausible claims is rooted in a lack of analytical thinking.