Act utilitarianism

Act utilitarianism is an ethical theory that judges an action’s morality based on its actual outcomes in the particular moment—the right choice is whatever yields the best results right then. The theory rests on the principle of utility, which Jeremy Bentham famously summed up as “the greatest happiness for the greatest number.” Bentham also argued that humans are governed by two sovereign forces, pain and pleasure, and that these alone determine what we should do and what we actually do. Classical utilitarians like Bentham, John Stuart Mill, and Henry Sidgwick defined happiness as pleasure and the absence of pain.

Critics point out that act utilitarianism can seem to permit leisure activities that others might consider wrong, but more serious objections include that it could justify acts like torture or enslavement if those acts produce enough overall happiness. Act utilitarianism is often compared to rule utilitarianism, which holds that an action is right if it follows a moral rule that, when generally followed, would create the most happiness. While act utilitarianism looks at the actual consequences of a single act, rule utilitarianism considers the consequences of everyone following the same rule (including past and future cases). Some believe rule utilitarianism avoids the troubling implications that act utilitarianism can lead to.