Social class is an individual-level characteristic that reflects a person's objective material resources (e.g., income, education, and occupational prestige) and corresponding subjective perceptions of rank vis-à-vis others in the social hierarchy (Kraus, Piff, & Keltner, 2011). Drawing on theories of cultural psychology and social cognition, emerging psychological research suggests that social class influences people's social and cognitive tendencies, significantly shaping how they perceive, interpret, and react to their environments (Kraus, Piff, Mendoza-Denton, Rheinschmidt, & Keltner, in press; Piff, Kraus, Côté, Cheng, & Keltner, 2010). Specifically, the confluence of increased resources and rank, greater personal control, decreased vulnerability to environmental threat, and increased independence from others gives rise to self-focused social cognitive tendencies among upper-class individuals. By contrast, the confluence of decreased resources and rank, less personal control, increased vulnerability to threat, and increased dependence on others gives rise to other-focused social cognitive tendencies among lower-class individuals. Following from this theoretical framework, I tested the hypothesis that upper-class individuals, relative to lower-class individuals, engage in increased unethical behavior, and do so, in part, because of their more favorable attitudes toward greed.

Seven studies using experimental and naturalistic methods yielded evidence that supported this hypothesis. In my first two studies, upper-class individuals proved more likely than lower-class individuals to break the law while driving by cutting off other vehicles at a four-way intersection (Study 1) or failing to yield for a pedestrian at a crosswalk (Study 2). Follow-up laboratory studies further tested the association between social class and unethical tendencies. In Study 3, upper-class individuals were more likely than lower-class individuals to exhibit unethical decision-making tendencies. In Study 4, inducing in participants an upper-class mindset caused them to take more valued goods from others compared to participants who experienced a lower-class mindset. In Study 5, upper-class individuals were more likely than lower-class individuals to endorse lying in a hypothetical negotiation. In Study 6, upper-class individuals were more likely than lower-class individuals to cheat in a game to increase their chances of winning a prize. Finally, in Study 7, upper-class individuals endorsed more unethical behavior at work than lower-class individuals. Across studies, I provide mediator and moderator data in support of the hypothesis that upper-class individuals' unethical tendencies are driven, in part, by their more favorable attitudes toward greed.