Representations of what’s possible reflect others’ epistemic states

People’s judgments about what an agent can do are shaped by various constraints, including probability, morality, and normality. However, little is known about how these representations of possible actions—what we call modal space representations—are influenced by an agent’s knowledge of their environment. Across two studies, we investigated whether epistemic constraints systematically shift modal space representations and whether these shifts affect high-level force judgments. Study 1 replicated prior findings that the first actions that come to mind are perceived as the most probable, moral, and normal, and demonstrated that these constraints apply regardless of an agent’s epistemic state. Study 2 showed that limiting an agent’s knowledge changes which actions people perceive to be available for the agent, which in turn affects whether people judged an agent as being “forced” to take a particular action. These findings highlight the role of Theory of Mind in modal cognition, revealing how epistemic constraints shape perceptions of possibilities.