Mixed human/entity games and the anomalous effects of misattributing strategic agency

People sometimes make better decisions either by treating inanimate objects like strategic reasoners or by treating other reasoners as if they were inanimate objects. I advance “strategic agenthood attribution” as a psychological mechanism for modulating economic behavior. From a design perspective, inducing or suppressing the attribution of strategic abilities can influence aggregate social outcomes. Drawing from experiments in behavioral and institutional economics, developmental and social psychology, and human–robot interaction, I document human strategic reasoning in environments that mix typical adult humans with other kinds of entities. I then discuss anomalous misattributions of strategic agenthood and non-agenthood, with special attention to settings in which two types of error—either attributing strategic reasoning abilities to objects that can’t think, or failing to attribute such abilities to typical human subjects—actually led to better economic outcomes. Because over- and under-mentalizing are endemic to human decision-making processes, game theory can be applied to improve interaction design, whether or not a given interaction is a game. I show that the flexible nature of human agenthood attribution increases the scope of game theory in some places, reduces it elsewhere, and generally introduces behavioral economics as a promising source of theory for human interactions with equivocal agents.