Supplementary material from "Social class and wise reasoning about interpersonal conflicts across regions, persons and situations"

We propose that class is inversely related to a propensity of using wise reasoning (recognizing limits of their knowledge, consider world in flux and change, acknowledge and integrate different perspectives) in interpersonal situations, contrary to established class advantage in abstract cognition. Two studies—an online survey from regions differing in economic affluence (N = 2,145) and a representative in-lab study with stratified sampling of adults from working and middle-class backgrounds (N = 299)—tested this proposition, indicating that higher social class consistently related to lower levels of wise reasoning across different levels of analysis, including regional and individual differences, and subjective construal of specific situations. The results held across personal and standardized hypothetical situations, across self-reported and observed wise reasoning, and when controlling for fluid and crystallized cognitive abilities. Consistent with the ecological framework, class differences in wise reasoning were specific to interpersonal (versus societal) conflicts. These findings suggest that higher social class weighs individuals down by providing the ecological constraints that undermine wise reasoning about interpersonal affairs.