Ultimately,
Mill explains, the above discussion shows how, besides desiring things that are a means to happiness, people can desire things that are “a part of happiness.” And this is the “proof [to which] the principle of
utility is susceptible.” If Mill can show that no natural human desire is anything but a desire for “
either a part of happiness or a means to happiness,” then he has proven that happiness is the only goal of human life, the proper standard to make moral judgments about good and evil actions, and the sole “criterion of morality” itself. And it is possible to give this proof through “fact and experience.” Mill argues that “practiced self-consciousness and self-observation” will show anyone that “to think of an object as desirable […] and to think of it as pleasant are one and the same thing.”