The mood of "Utilitarianism" is reasoned and unemotional. Mill approaches the subject matter with a sense of intellectual seriousness and a commitment to logical argumentation. While he is passionate about promoting utilitarianism as a moral and political philosophy, his writing is measured and objective, focusing on presenting his ideas with clarity and precision. Ultimately, his goal is to persuade readers of the validity and practicality of utilitarian principles through reasoned discourse rather than resorting to emotional appeals, and he rarely refers to any particular examples of immorality or injustice that might rouse strong feelings.
Further, he argues against the common belief that moral judgements are a matter of instinct or feeling, claiming instead that our moral beliefs proceed logically from our sense of reason or rationality. In the opening section of the essay, he writes:
Our moral faculty, according to all those of its interpreters who are entitled to the name of thinkers, supplies us only with the general principles of moral judgments; it is a branch of our reason, not of our sensitive faculty, and must be looked to for the abstract doctrines of morality, not for perception of it in the concrete.
Mill claims that moral judgments, or our ability to distinguish right from wrong, are not primarily a matter of “perception” or feeling, such as the physical senses. In other words, a person does not simply intuit the “general principles” of morality as simply as determining if something is hot or cold. Because of this, Mill suggests, we must coolly apply our own sense of reason to the difficult task of deriving moral principles, without getting first distracted by any particular “concrete” example.