Note: Mill doesn't get around to telling his readers what the utilitarian theory of ethics is until page seven. You may find it helpful to read the first paragraph (at least) of the editor's introduction, or to look at Mill's own explanation on page seven (in the first paragraph beginning on that page), before reading Chapter 1.
1. In Chapter 1 Mill explains his purpose. He will not survey and criticize other people’s theories of ethics. He will try to explain and support his own, which he calls the ‘utilitarian’ or ‘happiness’ theory. But he does offer a brief categorization of types of ethical theory: there are ‘intuitive’ theories and ‘inductive’ theories. According to the intuitive theories, we can know what is right and wrong ‘a priori’ – that is, we can know just by thinking, without consulting observations or experiments, what the basic principles of morality are. One way of expressing this thought is to say that those principles are ‘self-evident’. Another way to express it is to say that we know them by ‘rational intuition’. Inductive theories, by contrast, do rely on empirical experience (observation and experiment). Mill says nothing about how this is supposed to work.
2. Mill claims that both theories agree in holding that principles are essential to ethics. What experience or intuition can teach us is not what is right or wrong in particular cases, but only the general principles we can use to try to determine what is right or wrong in particular cases. As we will learn, not every philosopher agrees with Mill about this. Mill goes on to say that, since ethics is based on principles, what we want from ethical theory is a way to do one of two things: either the theory should explain how all the principles may be derived from one fundamental principle, or, if this is impossible, it should explain how to rank the various principles in a “determinate order of precedence.” (As examples of principles, here, you might take the Ten Commandments.)
3. Note the criticism of Kant on p.4. What exactly is Mill claiming about Kant's theory of ethics? If you have read (or read about) Kant, does it seem to you that his criticism of Kant is sound?
4. Notice Mill’s remarks on the possibility of proving that his theory is correct. Why does he think that, in one sense, proof is impossible? In what sense is it possible?
5. Chapter 2 attempts to clarify the meaning of the utilitarian theory of ethics by showing that a number of common objections to it are based on misunderstandings. The first of these objections is met (on pp.6-7) by pointing out that 'utility' includes 'pleasure' and is not opposed to it. See if you can state the objection itself in your own words. What would someone say if he or she was criticizing utilitarianism in the way that Mill is imagining here?
6. A second objection is addressed in the pages 7-12. It is stated in the second paragraph beginning on p.7. "Now such a theory of life..." Mill's reply hinges on a distinction between higher and lower pleasures. Try to get clear on what sorts of pleasures Mill thinks are 'higher' and what sorts 'lower.' Try also to understand and evaluate the reasoning he uses to defend his way of drawing this distinction. (This involves developing the notion of a 'competent judge.')
7. Note that this section culminates in a more detailed statement of the utilitarian doctrine (in the paragraph that starts at the top of page 12).