In moral philosophy, deontological ethics or deontology (from Ancient Greek δέον (déon) 'duty, obligation' and -λογία (-logía) 'study of') is the normative ethical theory that the morality of an action should be based on whether that action itself is right or wrong under a series of rules and principles, rather than based on the consequences of the action. It is sometimes described as duty-, obligation-, or rule-based ethics. Deontological ethics is commonly contrasted to utilitarianism and other consequentialist theories, virtue ethics, and pragmatic ethics. In the deontological approach, the inherent rightfulness of actions is considered more important than their consequences.
The term deontological was first used to describe the current, specialised definition by C. D. Broad in his 1930 book, Five Types of Ethical Theory. Older usage of the term goes back to Jeremy Bentham, who coined it prior to 1816 as a synonym of dicastic or censorial ethics (i.e., ethics based on judgement). The more general sense of the word is retained in French, especially in the term code de déontologie (ethical code), in the context of professional ethics.
