A model of social duties

We develop a formal model of social duties. Duties to respect entitlements (duties of justice) differ from duties to promote well-being (duties of charity). A situationspecific version of our model takes entitlements as primitives. A fully portable version derives entitlements from situational characteristics. Utility functions obtain kinks where duties of justice and charity are exactly satisfied. Actions at these kinks are candidates for descriptive social norms. Empirically, duties are identified using Krupka-Weber appropriateness ratings, with negative ratings indicating entitlement violations. The model's predictions are confronted with established regularities and new survey evidence in seven pre-registered applications.