In Utilitarianism, J.S. Mill gives an account for the reasons one must abide by the principles of Utilitarianism. Also referred to as the Greatest-happiness Principle, this doctrine promotes the greatest happiness for the greatest amount of people. More specifically, Utilitarianism is a form of consequentialism, holding that the right act is that which yields the greatest net utility, or "the total amount of pleasure minus the total amount of pain", for all individuals affected by said act (Joyce, lecture notes from 03/30).
In defining utilitarianism, J.S. Mill counters the popular belief that this theory only deals with the pleasure yielded by actions of individuals by stating that, "the theory of utility... [is] not something to be contradistinguished from pleasure, but pleasure... together with exemption from pain" (596). He goes on to argue that the foundation of this principle lies in the fact that an individual's action is right if it tends to promote happiness and wrong if it tends to "produce the reverse of happiness" (597). For example, an enemy forcibly entered your village with the intent on killing every woman and child in town if no one turned over the sniper that took some of their men out. If you tell them who the sniper is, no harm will be done to the women and children, but since the sniper is long gone, you decide to tell the enemy that the town bum is the sniper. Since you judge his life to be of least worth in all of the village in terms of future goodness, would it be right to send him to his death? The answer is yes, this act would be the right act as it would promote the happiness in the rest of the village because his life isn't worth the hundreds of lives of women and children (Paraphrased from Joyce, Lecture notes 03/30).
Mill believes that the most desirable things in this world are desirable, "either for the pleasure inherent in themselves, or as means to the promotion of pleasure and the prevention of pain" (597). Therefore, when confronted with two pleasures or acts, one must choose the one that will create the most utility, or happiness and pleasure, for the largest number of people. One might contradict this by saying that men can do without happiness and that happiness isn't the purpose of human life. J.S. Mill rebuts by stating that when these critics talk about happiness, they mean a "continuity of highly pleasurable excitement," which is evidently impossible (600). To Mill, utility includes not only the pursuit of happiness, but the prevention of unhappiness and pain. this proves to be the truest theory of the purpose of human life because happiness is incorporated with the endless pursuit to prevent pain.
Mill also argues that not all forms of pleasure are of equal value. Holding that quality of pleasures is certainly better than quantity, Mill states that, "It is better to be a human being dissatisfied than a pig satisfied, better to be Socrates dissatisfied than a fool satisfied" (598). More...