If one holds a view in moral philosophy, how is it to be supported? Basically, there are two ways. One is to argue in favor of one's own position either positively by stating reasons for holding it or defensively by answering objections to it. The other is to show that there are problems with alternative views.

Most of Mill's Utilitarianism is a defense of the utilitarian view. In Chapter 2 he answers a series of objections to utilitarianism and in Chapter 5 answers the major objection that justice is independent of utility. In Chapter 3 Mill analyzes sources for motivation to be moral and claims that utilitarianism has a source of motivation lacking in other theories. In Chapter 4 he gives psychological evidence for a hedonistic theory of ultimate value. It is primarily in Chapter 1 that Mill explicitly criticizes alternative ethical theories, and his remarks are very brief. He says that to show the deficiencies of his opponents “would imply a complete survey and criticism of past and present ethical doctrine,” and that it is not his present purpose to do so. In some of his other writings, however, he goes into greater detail in showing the deficiencies of other views. Those readers who are narrowly concerned with the interpretation and significance of the explicit controversies of Utilitarianism may wish to skip or to skim this chapter. For those interested in the status of utilitarianism as a viable ethical theory, however, I believe that this chapter is important.