Why do people always want more? Perceived economic inequality leads people to be greedy by enhancing relative deprivation.

Greedy phenomena have dramatically increased in societies. However, despite the universality of greedy behaviour, empirical research on the causes of greed is scarce. In this context, we propose that perceived economic inequality may be an important factor influencing greed. Study 1 provided primary evidence of a positive relationship between perceived economic inequality and greed, based on data from a large-scale social survey (CFPS 2018, N = 14,317). Employing well-established questionnaires, Study 2A (N = 200) and Study 2B (N = 399) revealed that perceived economic inequality positively predicts greed, with relative deprivation playing a mediating role. Study 3A (N = 200) and Study 3B (N = 200) manipulated perceived economic inequality to provide causal evidence of its effects on greed and to replicate the mediating effect of relative deprivation. Finally, Study 4 (N = 372), using a blockage manipulation design, showed that the effect of perceived economic inequality on greed significantly decreases when relative deprivation is suppressed. In summary, the results of these six studies consistently suggest that perceived economic inequality positively affects greed and that this effect is mediated by relative deprivation.