Everything has a limit: How intellectual humility lowers the preference for naturalness as reflected in drug choice

Across a broad range of cultures, people demonstrate a strong preference for items that are labeled as natural. Yet, less is known about methods that can reduce the natural-is-better bias. The objective of the present research is to see whether intellectual humility, a moral virtue that can be understood as a more open and curious mindset, reduces naturalness bias in terms of drug-related decisions. We tested our hypotheses across four studies using different populations (university students and community adults) and methods (correlational and experimental). Study 1 involved a survey exploring whether university students choosing a synthetic drug tended to display a higher level of intellectual humility than those choosing a natural drug. Study 2 assessed the link using observation of real-world behavior in non-student adults. Study 3 adopted an experimental approach to test the idea that reflecting on one's intellectual fallibility can at least temporarily reduce naturalness bias on drug choice. Study 4 examined the potential mediating mechanism underlying the observed effect. We found correlational and experimental evidence that participants higher in intellectual humility were more likely to choose the synthetic drug than those lower in intellectual humility in both self-report and behavioral measures. The results also demonstrate that openness to experience mediated the effect of intellectual humility on naturalness bias. These results highlight intellectual humility as a malleable, psychological variable that can combat biased thinking associated with health-related decision-making.