J. S. Mill: 'On Liberty' and Other Writings (Cambridge Texts in the History of Political Thought) [ペーパーバック]

1. Introduction
John Stuart Mill opens his first chapter by establishing the sole basis of his moral system: "I regard utility as the ultimate appeal on all ethical questions; but it must be utility in the largest sense, grounded on the permanent interests of man as a progressive being" (¶ 11). His philosophy thus holds that actions are right in proportion to their tendency to promote happiness, and wrong in proportion to their tendency to promote unhappiness. Happiness is equivalent to pleasure and the absence of pain; unhappiness is equivalent to pain and the privation of pleasure. In this way, utilitarianism sets out a basic system to determine the morality of all actions, both private and public, individual and societal. On this basis, John Stuart Mill, in his essay On Liberty, sets out to define the proper limits of government and society on the freedom of the individual.

2. On Liberty
a. Liberty
John Stuart Mill opens his essay by defining the subject he will explore: "the nature and limits of the power which can be legitimately exercised by society over the individual" (¶ 1). This, he calls "Civil, or Social Liberty." The problem he will explore is the "struggle between Liberty and Authority," which is "the most conspicuous feature in the portions of history with which we are earliest familiar" (¶ 2). He explores the extent to which man's liberty may properly be checked by authority and he outlines the ways in which liberty is threatened by various tyrannies, such as the "tyranny of the political rulers" and the "tyranny of the majority" (social tyranny).
For Mill, liberty permits man to act as he wishes when no harm falls upon other people. It involves a series of rights and includes liberty of conscience, liberty of thought and feeling, freedom of opinion and sentiment, liberty of tastes and pursuits and of framing a plan of life to suit one's character, to do as one wishes in a way that does not harm others or impede from the exercise of this right by others, and freedom of association, with some limits (¶ 12).
Mill concludes that "the sole end for which mankind are warranted, individually or collectively, in interfering with the liberty of action of any of their number, is self-protection" (¶ 9). Accordingly, rulers are unable to use their power arbitrarily in a way that harms society. Social liberty was protected by obtaining "recognition of certain immunities, called political liberties or rights, which it was to be regarded as a breach of duty in the ruler to infringe," and also by establishing of a system of "constitutional checks" (¶ 2). With these two measures in place, the tyranny of rulers is checked.
However, limiting the power of government is insufficient to the end of guarding liberty. Mill then outlines a system for checking "social tyranny," for "Society can and does execute its own mandates: and if it issues wrong mandates instead of right, or any mandates at all in things with which it ought not to meddle, it practices a social tyranny more formidable than many kinds of political oppression, since, though not usually upheld by such extreme penalties, it leaves fewer means of escape, penetrating much more deeply into the details of life, and enslaving the soul itself" (¶ 6). Mill lays out a series of rules of conduct, some of which are enacted by law, to offer protections within this scenario.

b. Tyranny
Mill's essay describes two threats to liberty: social tyranny, comprised of public opinion, as well as the tyranny of the public authorities. Society must be on its guard against the tyranny of the majority, which "was at first, and is still vulgarly, held in dread, chiefly as operating through the acts of the public authorities" (¶ 6). This tyranny manifests itself as a "social tyranny" whenever society executes "wrong mandates instead of right, or any mandates at all in things with which it ought not to meddle" (¶ 5). Mill describes this tyranny as even more dangerous than the tyranny of rulers or magistrates, and calls for protections against society when it passes "its own ideas and practices as rules of conduct on those who dissent from them" (¶ 5).