This post brings up the latest paper by Dan Kahan and his colleagues, Erica Dawson, Ellen Peters, and Paul Slovic: “Motivated Numeracy and Enlightened Self-Government,” Cultural Cognition Project, Working Paper No. 116. This paper strengthens the already strong arguments.
The experiment that was the subject of this paper was designed to test two opposing accounts of conflict over decision relevant science. The first—the Science Comprehension Thesis (“SCT”)—attributes such conflicts to the limited capacity of the public to understand the significance of valid empirical evidence. The second—the Identity-protective Cognition Thesis (“ICT”)—sees a particular recurring form of group conflict as disabling the capacities that individuals have to make sense of decision-relevant science: when policy-relevant facts become identified as symbols of membership in and loyalty to affinity groups that figure in important ways in individuals’ lives, they will be motivated to engage empirical evidence and other information in a manner that more reliably connects their beliefs to the positions that predominate in their particular groups than to the positions that are best supported by the evidence.
Study subjects were assigned to analyze the results of an experiment. Correctly interpreting the data required subjects to engage in a form of quantitative analysis—identifying covariance between experimental treatment and outcomes—that is essential to valid causal inference but that many people have difficulty performing reliably and accurately. Not surprisingly, we found that when the experiment was styled as one involving a skin-rash treatment, the subjects’ probability of identifying the most supported outcome was highly sensitive to subjects’ numeracy, a capacity to understand and make proper use of quantitative information in reasoning tasks.
Also subjects’ likelihood of correctly identifying the correct response varied in relation to the subjects’ political outlooks when the experiment was styled as one involving a gun-control ban. Subjects were more likely to correctly identify the result most supported by the data when doing so affirmed the position one would expect them to be politically predisposed to accept—that the ban decreased crime, in the case of more liberal subjects who identify with the Democratic Party; and that it increased crime, in the case of more conservative ones who identify with Republicans—than when the correct interpretation of the data threatened or disappointed their predispositions.
SCT predicted that polarization among high-Numeracy partisans would be lower, however, than among low-Numeracy ones in the gun-ban conditions, but the data did not support this prediction.
On the contrary, numeracy magnified political polarization among high numeracy partisans. This result was consistent with ICT. More numerate individuals are benefited from forming identity-congruent beliefs just as much as less numerate individuals are, and harmed just as much from forming identity-non congruent beliefs. But more numerate individuals have a cognitive ability that lower numeracy ones do not. ICT predicts that more numerate individuals will use that ability opportunistically in a manner geared to promoting their interest in forming and persisting in identity-protective beliefs.
Kahan et al state that it is perfectly rational, from an individual-welfare perspective, for individuals to engage decision-relevant science in a manner that promotes culturally or politically congenial beliefs. Making a mistake about the best-available evidence on an issue like climate change, nuclear waste disposal, or gun control will not increase the risk an ordinary member of the public faces, while forming a belief at odds with the one that predominates on it within important affinity groups of which they are members could expose him or her to an array of highly unpleasant consequences.
Kahan makes clear that to conclude that ideologically motivated reasoning is rational obviously does not imply that it is socially or morally desirable. Indeed, Kahan and his colleagues state that:
the implicit conflation of individual rationality and collective well being has long been recognized to be a recipe for confusion, one that not only distorts inquiry into the mechanisms of individual decision making but also impedes the identification of social institutions that remove any conflict between those mechanisms and attainment of the public good. Accounts that misunderstand the expressive rationality of ideologically motivated cognition are unlikely to generate reliable insights into strategies for counteracting the particular threat that persistent political conflict over decision-relevant science poses to enlightened democratic policy-making.
Thus, improving public understanding of science and propagating critical reasoning skills will not end persistent public conflict over decision-relevant science. Only removing the source of the motivation to process scientific evidence in an identity-protective fashion can. The conditions that generate symbolic associations between positions on risk and like facts, on the one hand, and cultural identities, on the other, must be neutralized in order to assure that citizens make use of their capacity for science comprehension. Kahan and his colleagues assert that In a deliberative environment protected from the entanglement of cultural meanings and policy-relevant facts, there is little reason to assume that ordinary citizens will be unable to make an intelligent contribution to public policymaking. According to Kahan, they are able to accomplish this feat because they are experts at something else: identifying who knows what about what, a form of rational processing of information that features consulting others whose basic outlooks individuals share and whose knowledge and insights they can therefore reliably gauge.
Kahan et. al conclude:
Just as individual well-being depends on the quality of the natural environment, so the collective welfare of democracy depends on the quality of a science communication environment hospitable to the exercise of the ordinarily reliable reasoning faculties that ordinary citizens use to discern what is collectively known. Identifying strategies for protecting the science communication environment from antagonistic cultural meanings—and for decontaminating it when such protective measures fail—is the most critical contribution that decision science can make to the practice of democratic government.