Like other tyrannies, the tyranny of the majority was at first, and is still vulgarly, held in dread, chiefly as operating through the acts of the public authorities. But reflecting persons perceived that when society is itself the tyrant—society collectively over the separate individuals who compose it—its means of tyrannising are not restricted to the acts which it may do by the hands of its political functionaries. 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 practises 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. Protection, therefore, against the tyranny of the magistrate1 is not enough; there needs protection also against the tyranny of the prevailing opinion and feeling, against the tendency of society to impose, by other means than civil penalties, its own ideas and practices as rules of conduct on those who dissent from them; to fetter the development and, if possible, prevent the formation of any individuality not in harmony with its ways, and compel all characters to fashion themselves upon the model of its own. There is a limit to the legitimate interference of collective opinion with individual independence; and to find that limit, and maintain it against encroachment, is as indispensable to a good condition of human affairs as protection against political despotism.2

But though this proposition is not likely to be contested in general terms, the practical question, where to place the limit—how to make the fitting adjustment between individual independence and social control—is a subject on which nearly everything remains to be done. All that makes existence valuable to anyone depends on the enforcement of restraints upon the actions of other people. Some rules of conduct, therefore, must be imposed—by law in the first place, and by opinion on many things which are not fit subjects for the operation of law. What these rules should be is the principal question in human affairs; but if we except a few of the most obvious cases, it is one of those which least progress has been made in resolving. No two ages, and scarcely any two countries, have decided it alike; and the decision of one age or country is a wonder to another. Yet the people of any given age and country no more suspect any difficulty in it than if it were a subject on which mankind had always been agreed. The rules which obtain among themselves appear to them self-evident and self-justifying. This all but universal illusion is one of the examples of the magical influence of custom, which is not only, as the proverb says, a second nature, but is continually mistaken for the first. The effect of custom, in preventing any misgiving respecting the rules of conduct which mankind impose on one another, is all the more complete because the subject is one on which it is not generally considered necessary that reasons should be given, either by one person to others, or by each to himself. People are accustomed to believe, and have been encouraged in the belief by some who aspire to the character of philosophers, that their feelings on subjects of this nature are better than reasons and render reasons unnecessary. The practical principle which guides them to their opinions on the regulation of human conduct is the feeling in each person’s mind that everybody should be required to act as he, and those with whom he sympathises, would like them to act.

In the context of the passage as a whole, the first paragraph primarily serves to

A. undercut a common justification for a practice the author opposes
B. identify factors that impeded the author’s freedom to investigate his subject
C. express the author’s concern that his views will go unheard
D. establish the context for the problem the author seeks to address
E. cite a widely held argument in support of the author’s thesis