Part of a series on Utilitarianism Predecessors Epicurus David Hume  William Godwin  Francis Hutcheson People Jeremy Bentham  John Stuart Mill Henry Sidgwick  Richard Mervyn Hare  Peter Singer Types of utilitarianism Preference  Rule  Act Two-level  Total  Average Relative  Negative  Hedonism Enlightened self-interest Key concepts Pain  Suffering  Pleasure Utility  Happiness  Eudaimonia Consequentialism  Felicific calculus Problems Mere addition paradox Paradox of hedonism Utility monster Related topics Rational choice theory  Game theory Social choice  Neoclassical economics   Politics portal v d e

The utility monster is a thought experiment in the study of ethics. It was created by philosopher Robert Nozick in 1974 as a criticism of utilitarianism.

In the thought experiment a hypothetical being is proposed who receives as much or more utility from each additional unit of a resource he consumes as the first unit he consumes. In other words the utility monster is not subject to diminishing marginal returns with regard to utility but instead experiences constant marginal returns or even increasing marginal returns.

Since ordinary people receive less utility with each additional unit consumed if the utility monster existed it would justify the mistreatment and perhaps annihilation of everyone else according to the doctrine of utilitarianism.

According to the philosopher Robert Nozick: "Utilitarian theory is embarrassed by the possibility of utility monsters who get enormously greater sums of utility from any sacrifice of others than these others lose . . . the theory seems to require that we all be sacrificed in the monsters maw in order to increase total utility."1

This thought experiment attempts to show that utilitarianism is not actually egalitarian even though it appears to be at first glance.

It is the opposite of the mere addition paradox which argues that utilitarianism may lead to a very heavily populated dystopic world.

See also Average and total utilitarianism References Robert Nozick Anarchy State and Utopia (1974)