Individual Sense of Justice: A Utility Representation

We present an axiomatic model depicting the choice behavior of a self-interest seeking moral individual over random allocation procedures. Individual preferences are decomposed into a self-interest component and a component representing the individual's moral value judgment. Each component has a distinct utility representation, and the preference relation depicting the choice behavior is representable by a real-valued function defined on the components utilities. The utility representing the self-interest component is linear and the utility representing the individual's moral value judgment is quasi-concave. The addition of a hexagon condition implies that the utility representing the individual's preference is additively separable in the components utilities.