Someone follows a rule they would rather not follow, purely because it is the rule. Why is that the textbook case of duty ethics — and where does it stop?
Because the action is done out of duty and against inclination, which is exactly what Kant counts as moral worth — but only as long as the rule can be justified by reason.
Take the plain case: a pupil goes out to the schoolyard at break, although he would rather stay in the classroom, because the house rules require it.
- Duty versus inclination. Kant distinguishes strictly between inclination (Neigung) — what one would like to do — and duty (Pflicht) — what reason, or the rule, prescribes. Acting against one's own inclination out of respect for the rule is acting from duty, and that is what gives the action its moral quality on this account. An action that merely happens to coincide with duty, done because one felt like it, does not have the same standing.
- The limit. If the rule were unreasonable or unjust, duty ethics would require him to question the rule on rational grounds rather than obey it blindly. Since a break-outside rule is rationally justifiable — fresh air, supervision, a break from the room — following it remains a duty.
That limiting clause is the part worth remembering, because it disposes of the most common caricature of deontology. Duty ethics is not obedience to authority: the duty is to what reason can justify, and a rule that fails that test generates no duty. It is the rational justifiability of the rule, not its existence, that binds.
Tip: Two questions in order: Is this rule rationally justifiable? and only then Am I doing it out of duty rather than because it suits me? Skip the first and you have authority-worship, not ethics.
Go deeper:
Stanford Encyclopedia: Kant's Moral Philosophy — section 2 on duty versus inclination, including the standard objection that it values the wrong motive.
Crash Course Philosophy: Kant & Categorical Imperatives — the shortest honest introduction to why Kant grounds duty in reason rather than authority.- Internet Encyclopedia: Immanuel Kant — the wider system the moral philosophy sits in, if you want the why behind the why.