Cusimano, C., & Lombrozo, T. (2020, July 20).
When faced with a dilemma between believing what is supported by an impartial assessment of the evidence (e.g., that one’s friend is guilty of a crime) and believing what would better fulfill a moral obligation (e.g., that the friend is innocent), people often believe in line with the latter. But is this how people think beliefs ought to be formed? We addressed this question across three studies and found that, across a diverse set of everyday situations, people treat moral considerations as legitimate grounds for believing propositions that are unsupported by objective, evidence-based reasoning. We further document two ways in which moral evaluations affect how people prescribe beliefs to others. First, the moral value of a belief affects the evidential threshold required to believe, such that morally good beliefs demand less evidence than morally bad beliefs. Second, people sometimes treat the moral value of a belief as an independent justification for belief, and so sometimes prescribe evidentially poor beliefs to others. Together these results show that, in the folk ethics of belief, morality can justify and demand motivated reasoning.
From the Discussion
Additionally, participants reported that moral concerns affected the standards of evidence that apply to belief, such that morally-desirable beliefs require less evidence than morally-undesirable beliefs. In Study 1, participants reported that, relative to an impartial observer with the same information, someone with a moral reason to be optimistic had a wider range of beliefs that could be considered“consistent with” and “based on” the evidence. Critically however, the broader range of beliefs that were consistent with the same evidence were only beliefs that were more morally desirable; morally undesirable beliefs were not more consistent with the evidence. In Studies 2 and 3, participants agreed more strongly that someone who had a moral reason to adopt a desirable belief had sufficient evidence to do so compared to someone who lacked a moral reason, even though they formed the same belief on the basis of the same evidence. Likewise, on average, participants judged that when someone adopted the morally undesirable belief, they were more often judged as having insufficient evidence for doing so relative to someone who lacked a moral reason (again, even though they formed the same belief on the basis of the same evidence). Finally, in Study 2 (though not in Study 3), these judgments replicated using an indirect measure of evidentiary quality; namely, attributions of knowledge. In sum, these findings document that one reason people may prescribe a motivated belief to someone is because morality changes how much evidence they consider to be required to hold the belief in an evidentially-sound way.
Editor's Note: Huge implications for psychotherapy.