“There are many who consider as an injury to themselves any conduct which they have a distaste for, and resent it as an outrage to their feelings as a religious bigot, when charged with disregarding the religious feelings of others, has been known to retort that they disregard his feelings, by persisting in their abominable worship or creed. Over himself, over his own body and mind, the individual is sovereign.” In the part which merely concerns himself, his independence is, of right, absolute. The only part of the conduct of any one, for which he is amenable to society, is that which concerns others.

To justify that, the conduct from which it is desired to deter him must be calculated to produce evil to someone else. These are good reasons for remonstrating with him, or reasoning with him, or persuading him, or entreating him, but not for compelling him, or visiting him with any evil, in case he do otherwise. He cannot rightfully be compelled to do or forbear because it will be better for him to do so, because it will make him happier, because, in the opinions of others, to do so would be wise, or even right. His own good, either physical or moral, is not a sufficient warrant. That the only purpose for which power can be rightfully exercised over any member of a civilized community, against his will, is to prevent harm to others. That principle is, 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. “The object of this Essay is to assert one very simple principle, as entitled to govern absolutely the dealings of society with the individual in the way of compulsion and control, whether the means used be physical force in the form of legal penalties, or the moral coercion of public opinion.

Mill on liberty utilitarianism