Mill write in his "Introductory" to this work the following: "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. 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. 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. His own good, either physical or moral,
is not a sufficient warrant. He cannot rightfully be compelled to Ido 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. 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. To justify that, the conduct from which
it is desired to deter him must be calculated to produce evil to some one else . The only part
of the conduct of any one, for which he is amenable to society, is that which concerns
others. In the part which merely concerns himself, his independence is, of right, absolute.
Over himself, over his own body and mind, the individual is sovereign."