Key concepts:
Rule Utilitarianism
Mill argues that moral judgments should not be made case by case (as in Bentham’s act utilitarianism) but by appeal to rules. A rule is justified if, when generally followed, it maximises happiness for the greatest amount of people.
Qualitative approach
There’s more to life than just physical pleasures, in fact, pleasures and happiness have different qualities. For example, It is better to be a human being dissatisfied than a pig satisfied; better to be Socrates dissatisfied than a fool satisfied.
The Harm Principle
The idea that the only legitimate reason to restrict an individual’s liberty is to prevent harm to others. This ensures that the pursuit of the greatest happiness for the greatest number does not lead to oppressive outcomes.
Not lying example
Rule utilitarianism provides a prescriptive argument that we ought to not lie. Indeed, consider the murderer at the door example. The rule utilitarian would decide to not lie about his friend’s location, because otherwise, a world where lying is commonplace is not desirable for him.
Objection to the example
There are several objections to this prescriptive argument. Consider the following argument, the “not lying” rule is justified not because we know that this will maximise utility (we cannot know without empirical evidence) but because it is not rational to have a society in which lying is commonplace. Therefore, this is a deontological belief and not a utilitarian one.
Objection to the attempt to object the Objection
If rule utilitarianism attempts to dodge this accusation, then it falls back into Act Utilitarianism. For example, it is not hard to imagine a scenario where an act which breaks the rules leads to greater utility — lying to a murderer about a friend’s location. In this case, we use act-utilitarianism to produce greater utility than rule-utilitarianism: therefore, act-utilitarianism trumps rule-utilitarianism.