Experimental Proof for the Motivational Importance of Reciprocity

Video taped group decision experiments on a two-person investment game were used to elicit the motivational structure of subjects' behavior. A majority of investors trusted (invested) and a majority of receivers reciprocated (returned). Cognition and decision were focused on extremes: total or no investment and equitable or no return. Subjects exhibited motivational heterogeneity in both roles, but both materialism and reciprocity proved stronger than altruism. The qualitative model of motivational attractors is introduced to explain observations. The model is also applied to the ultimatum game and compared to utilitarian, behavioral, and evolutionary approaches to the question of economic motivation.