 The word deontology derives from the Greek words for duty (deon) and science (or study) of (logos). In contemporary moral philosophy, deontology is one of those kinds of normative theories regarding which choices are morally required, forbidden, or permitted. In other words, deontology falls within the domain of moral theories that guide and assess our choices of what we ought to do (deontic theories), in contrast to those that guide and assess what kind of person we are and should be (aretaic [virtue] theories). And within the domain of moral theories that assess our choices, deontologists—those who subscribe to deontological theories of morality—stand in opposition to consequentialists.