What is "deontic logic"

n. 1 (context logic English) The study of obligation, permission, and related concepts. 2 (context logic English) A formal system capturing the concepts of obligation and permission.

n. the modal logic of obligation and permissibility

Deontic logic is the field of philosophical logic that is concerned with obligation, permission, and related concepts. Alternatively, a deontic logic is a formal system that attempts to capture the essential logical features of these concepts. Typically, a deontic logic uses OA to mean it is obligatory that A, (or it ought to be (the case) that A), and PA to mean it is permitted (or permissible) that A. The term deontic is derived from the ancient Greek déon - δέον (gen.: δέοντος), meaning, roughly, that which is binding or proper.