Unequal but not separate: Emergence of rich–poor cooperation in resource exchange

Abstract

Addressing inequality is a critical challenge for society as a whole and requires sustained efforts to promote fairness and opportunity for all. Filling in the resource gap across social classes is essential in reducing inequality. Previous studies have revealed that ingroup favouritism hinders the rich from cooperating with the poor and expands the wealth gap. Nevertheless, how to find ways of narrowing the gap between the rich and the poor remains an open question. Inducing rich–poor cooperation could be effective in eliciting resource flow across classes. In this study, two experiments using a modified Prisoner's Dilemma game were conducted in Japan (N = 213) and China (N = 150) to examine whether highlighting partners' cooperativeness under permeable group boundaries induces rich–poor cooperation. All participants were allocated to the rich group and participated in the game with programmed rich- or poor-group partner bots, whose cooperation rates were manipulated. Despite the initial resource disparities between participants and the partner bots, participants were more likely to select and cooperate with cooperative poor-group partners than with non-cooperative rich-group partners. Generalized trust played an important role in the enhancement of rich–poor cooperation. The findings shed light on the possibility of reducing inequality and promoting social mobility in society.