Mill, John Stuart (1806–73)

10. The utility principle

Though Mill deepened the utilitarian understanding of pleasure, desire, character and will, he never adequately re-examined the principle of utility itself. When he states the utilitarian doctrine before considering what kind of proof can be given of it, he states it thus: ‘Happiness is desirable, and the only thing desirable, as an end, all other things being only desirable as means to that end’ (1861a: 210). In effect, he takes his task to be that of demonstrating the truth of hedonism. All he has to say about the move from hedonism to the utility principle is that if ‘each person’s happiness is a good to that person’ then ‘the general happiness’ must be ‘a good to the aggregate of all persons’. In a letter in which he explains this unclear remark, he says: ‘I merely meant in this particular sentence to argue that since A’s happiness is a good, B’s a good, C’s a good, etc, the sum of all these goods must be a good’ (1972: 1414). This contains two inexplicit assumptions. The more obvious point is that an egoist may accept that Mill has shown that ‘each person’s happiness is a good to that person’, but deny that he has shown that happiness is a good tout court. The egoist denies that Mill has shown that everyone has reason to promote the happiness of anyone. That requires a separate postulate, as Henry Sidgwick pointed out.

The second inexplicit assumption is more subtle. At the end of the last chapter of Utilitarianism, ‘On the Connexion between Justice and Utility’, Mill does explain that he takes ‘perfect impartiality between persons’ to be part of the very meaning of the Greatest Happiness Principle:

So here Mill supplies the required postulate of impartiality. However, the concept of impartiality does not, on its own, yield utilitarianism’s aggregative principle of distribution. Maximizing the sum of individuals’ happiness, if it makes sense to talk in this way at all, is one way of being impartial: no individual’s happiness is given greater weight than any other’s in the procedure which determines the value of a state of affairs as a function of the happiness of individuals in that state of affairs. In this sense the procedure implements the principle, ‘Everybody to count for one, nobody for more than one’; but so does maximizing the average of all individuals’ unweighted happiness. Here too all individuals count for one and no more than one. In fact a wide variety of non-equivalent distributive principles is impartial in this way. The most one could get from combining a postulate of impartiality with hedonism is that ethical value is a positive impartial function of individual happiness and of nothing else. In a footnote to the paragraph Mill glosses the requirement of perfect impartiality as follows: ‘equal amounts of happiness are equally desirable, whether felt by the same or by different persons’. That does yield aggregative or average utilitarianism, but it follows neither from the thesis that happiness is the only thing desirable to human beings, nor from the formal notion of impartiality (see Impartiality §2).