The Encyclopedia of Religious Ethics
In contemporary normative ethics, deontology (deon = duty, logos = science, study of) is a theory according to which agents deliberate about how they ought to act and evaluate whether their actions are right or wrong. On a rough characterization, deontology prioritizes the right over the good. Therefore, deontological normative theories require, forbid, or permit actions as a matter of principle, conforming to particular moral norms, largely regardless of the outcomes produced by those actions. In prioritizing the right over the good, deontological normative theories incorporate agent‐centered restrictions and respect for individual persons. Because “standard deontological views maintain that it is sometimes wrong to do what will produce the best available outcome overall,” Samuel Scheffler writes, such views incorporate agent‐centered restrictions. These restrictions on action: have the effect of denying that there is any non‐agent‐relative principle for ranking overall states of affairs from best to worst such that it [is] always permissible to produce the overall best available state of affairs so characterized. (1994, 2–3) Because of these agent‐centered (or agent‐relative) restrictions, the individual moral agent may be forbidden from performing some action that would promote the agent‐neutral state‐of‐affairs. In other words, deontological agent‐centered restrictions aim to capture the intuition about why the individual moral agent should not perform some action regardless of the good (i.e. agent‐neutral state‐of‐affairs) that may come about from performing it.
Ranganathan, Bharat, "Chapter 22: Deontology" (2022). Religion Faculty Publications. 11.