Hedonistic Utilitarianism

Hedonistic Utilitarianism is the form of utilitarianism focused on maximizing pleasure and minimizing pain.


Hedonism takes many forms that all prioritize pleasure. Psychological Hedonism claims that people are only motivated by pleasure and pain. Ethical Hedonism claims that only pleasure and pain are morally significant for determining what is right or wrong, good or bad. Axiological Hedonism claims that only pleasure and pain have intrinsic (dis)value. Therefore, it is clear that hedonistic utilitarianism will work with utility functions that represent pleasure or pain.

Classic utilitarianism was hedonistic and Bentham developed a felicific calculus to be used to calculate the degree of pleasure actions are likely to induce1looking at intensity, duration, certainty, propinquity, fecundity, purity, and extent.. Physical and spiritual, higher and lower pleasures were of concern. 

The pursuit of eudaimonia by ancient Greeks can be seen as a hedonistic approach that is non-utilitarian in its focus on living a virtuous life as the way to live a good, happy life. The approach of Epicurus resembles Rule Utilitarianism in the focus on developing long-term policies for maximal pleasure and freedom from pain and distress in the long run2This should be called Virtue Utilitarianism..

As with consequentialist utilitarianism, I sketch out the definition of hedonic utilitarianism in terms of meaning postulates constraining the scope of utility functions. The properties below do not precisely state that the functions measure pleasure and pain. I found it to be non-trivial to state this with SUMO’s ontology where measure assigns a physical quantity to a physical entity but pleasure is an abstract entity, an attribute3There is probably some hacky roundabout way to specify that one is measuring some physical quantity associated with pleasure. Or, perhaps, one will measure the score provided on happiness surveys, that is, the ontology will force us to be transparent as to how we measure pleasure!.


(documentation HedonisticUtilitarianism EnglishLanguage "Hedonistic Utilitarianism is a form of utilitarianism 
that focuses on maximizing pleasure and minimizing pain in evaluating the moral value of an action.")
(subclass HedonisticUtilitarianism Utilitarianism)

(documentation HedonisticUtilitarianTheory EnglishLanguage "A set of hedonistic utilitarian sentences.")
(subclass HedonisticUtilitarianTheory UtilitarianTheory)

(theoryPhilosophyPair HedonisticUtilitarianism HedonisticUtilitarianTheory)

  (instance ?HUT HedonisticUtilitarianTheory)
  (forall (?S)
      (element ?S ?HUT)
      (forall (?P ?UF ?FORMULA)
            (part ?P ?S)
            (equal ?P (AssignmentFn ?UF ?FORMULA))
            (instance ?FORMULA Formula)
            (instance ?UF UtilityFormulaFn))
          (instance ?UF HedonisticUtilityFormulaFn))))))

Hedonistic utilitarianism is defined as a subclass of utilitarianism where, for all theories, each instance of a utility function is a hedonistic utility function.

(documentation HedonisticUtilityFormulaFn EnglishLanguage "A UnaryFunction that maps Formulas to the net utility 
of that which is described where utility measures the pain and pleasure exhibited in the situation.")
(subclass HedonisticUtilityFormulaFn UtilityFormulaFn)

    (instance ?UF HedonisticUtilityFormulaFn)
    (greaterThan (AssignmentFn ?UF ?FORMULA) 0))
    (exists (?AGENT)
      (causesProposition ?FORMULA (attribute ?AGENT Pleasure))) Possibility))

  (exists (?AGENT)
      (causesProposition ?FORMULA (attribute ?AGENT Pleasure)))
    (exists (?UF)
        (instance ?UF HedonisticUtilityFormulaFn)
        (greaterThan (AssignmentFn ?UF ?FORMULA) 0))) Possibility))

If a hedonistic utility function assigns a utility greater than zero to a formula, then it’s possible for there to be an agent such that the state of affairs described by the formula causes this agent to have the pleasure attribute. Conversely, if there is an agent that is caused pleasure by the state of affairs described by the formula, then it’s possible for there to exist a hedonic utility function assigning the formula greater than zero utility.