“John Stuart Mill (20 May 1806 – 8 May 1873), English philosopher, political theorist, political economist, civil servant and Member of Parliament, was an influential liberal thinker of the 19th century whose works on liberty justified freedom of the individual in opposition to unlimited state control. He was an exponent of utilitarianism, an ethical theory developed by Jeremy Bentham, although his conception of it was very different from Bentham's. He clearly set forth the premises of the scientific method.”

“There have been, and may be again, great individual thinkers, in a general atmosphere of mental slavery.”

“He who knows only his own side of the case knows little of that. His reasons may be good, and no one may have been able to refute them. But if he is equally unable to refute the reasons on the opposite side, if he does not so much as know what they are, he has no ground for preferring either opinion... Nor is it enough that he should hear the opinions of adversaries from his own teachers, presented as they state them, and accompanied by what they offer as refutations. He must be able to hear them from persons who actually believe them...he must know them in their most plausible and persuasive form.”

“THE subject of this Essay is not the so-called Liberty of the Will, so unfortunately opposed to the misnamed doctrine of Philosophical Necessity; but Civil, or Social Liberty: the nature and limits of the power which can be legitimately exercised by society over the individual. A question seldom stated, and hardly ever discussed, in general terms, but which profoundly influences the practical controversies of the age by its latent presence, and is likely soon to make itself recognized as the vital question of the future. It is so far from being new, that, in a certain sense, it has divided mankind, almost from the remotest ages, but in the stage of progress into which the more civilized portions of the species have now entered, it presents itself under new conditions, and requires a different and more fundamental treatment.”

“No one can be a great thinker who does not recognize that as a thinker it is his first duty to follow his intellect to whatever conclusions it may lead.”

“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 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. 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 someone 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.”

“The liberty of the individual must be thus far limited, he must not make himself a nuisance to other people.”