Conflicting Obligations in Multi-agent Deontic Logic

Abstract

Extending John Horty’s multi-agent deontic logic to moral reasoning with subjective utilities, we provide a language and semantics to study moral reasoning with sentences like ‘Group ${\ensuremath{\mathcal{G}}}$ of agents ought see to it that φ in the interest of group ${\ensuremath{\mathcal{F}}}$’. We illustrate our deontic logic with a new formal analysis of the Prisoner’s Dilemma, thereby showing that games can be studied fruitfully with our deontic logic. Finally, we prove a characterization theorem on conflicting obligations.