Proceedings of the Annual Meeting of the Cognitive Science Society

Moral learners face an underdetermination problem – the rules they are taught cannot account for all novel cases. One way learners solve this problem is through closure principles, through which a learner assumes that anything that isn’t explicitly forbidden is permitted, and vice versa. The current work aims to explore whether closure rules are used when reasoning about obligations. Building on previous work, we ask 1) whether adults and children use obligation rules in a similar manner to rules about permissibility and impermissibility, and 2) how early in life these inference abilities emerge. Across two studies, we explore inferences about obligation from both adults (N = 120, Mage = 33.73 years) and children (N = 103, Mage = 5.52 years). We found that while both adults and children rationally learn closure principles consistent with deontic logic, children and adults make opposite inferences about novel cases when provided with obligation rules.