Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
The ability to form shared intentions and adjust one's choices in collaboration with others is a fundamental aspect of human nature. We discuss the forces that act for and against the evolution of this ability. In contrast to altruism and other non-fitness maximizing preferences, for large classes of games the ability to form shared intentions proliferates when rare without requiring group selection or assortativity in matching.