Balancing precedent and mutual benefit in tacit coordination

Human coordination depends on two complementary mechanisms: forward-looking strategies that enable flexible adaptation to new circumstances, and backward-looking mechanisms that rely on precedent, convention, and rule-following. Most cognitive and computational models of coordination emphasize one mechanism or the other—either explaining how equilibria emerge and persist when agents adapt their behavior based on past experience, or how agents creatively generate novel solutions and strategies to achieve anticipated mutual benefit in the challenges of the moment—but not how the two interact. Here we introduce a cognitive model and experimental paradigm to capture the dynamics of both processes and, crucially, the arbitration between them. In two preregistered experiments (n = 510; 30,420 choices), participants repeatedly solve coordination problems that can be addressed either by generalizing past solutions or by adopting novel ones when precedent becomes inefficient. This design allows us to examine the conditions under which individuals or dyads decide to abandon entrenched equilibria and transition to novel coordination solutions by arbitrating between mutual benefit and precedent. By formally modeling both forward- and backward-looking mechanisms, and the process of arbitration between them, we provide a unified framework for understanding how human coordination can be both stable and adaptable—a property that underlies everyday cooperative behavior, social norms, and institutional evolution.