No society in which these liberties are not, on the whole, respected, is free, whatever may be its form of government; and none is completely free in which they do not exist absolute and unqualified. The only freedom which deserves the name, is that of pursuing our own good in our own way, so long as we do not attempt to deprive others of theirs, or impede their efforts to obtain it. Each is the proper guardian of his own health, whether bodily, or mental and spiritual. Mankind are greater gainers by suffering each other to live as seems good to themselves, than by compelling each to live as seems good to the rest.
Though this doctrine is anything but new, and, to some persons, may have the air of a truism, there is no doctrine which stands more directly opposed to the general tendency of existing opinion and practice. Society has expended fully as much effort in the attempt (according to its lights) to compel people to conform to its notions of personal, as of social excellence. The ancient commonwealths thought themselves entitled to practise, and the ancient philosophers countenanced, the regulation of every part of private conduct by public authority, on the ground that the State had a deep interest in the whole bodily and mental discipline of every one of its citizens; a mode of thinking which may have been admissible in small republics surrounded by powerful enemies, in constant peril of being subverted by foreign attack or internal commotion, and to which even a short interval of relaxed energy and self-command might so easily be fatal, that they could not afford to wait for the salutary permanent effects of freedom. In the modern world, the greater size of political communities, and above all, the separation between spiritual and temporal authority (which placed the direction of men’s consciences in other hands than those which controlled their worldly affairs), prevented so great an interference by law in the details of private life; but the engines of moral repression have been wielded more strenuously against divergence from the reigning opinion in self-regarding, than even in social matters; religion, the most powerful of the elements which have entered into the formation of moral feeling, having almost always been governed either by the ambition of a hierarchy, seeking control over every department of human conduct, or by the spirit of Puritanism. And some of those modern reformers who have placed themselves in strongest opposition to the religions of the past, have been noway behind either churches or sects in their assertion of the right of spiritual domination: M. Comte, in particular, whose social system, as unfolded in his Traité de Politique Positive, aims at establishing (though by moral more than by legal appliances) a despotism of society over the individual, surpassing anything contemplated in the political ideal of the most rigid disciplinarian among the ancient philosophers.
Apart from the peculiar tenets of individual thinkers, there is also in the world at large an increasing inclination to stretch unduly the powers of society over the individual, both by the force of opinion and even by that of legislation: and as the tendency of all the changes taking place in the world is to strengthen society, and diminish the power of the individual, this encroachment is not one of the evils which tend spontaneously to disappear, but, on the contrary, to grow more and more formidable. The disposition of mankind, whether as rulers or as fellow-citizens to impose their own opinions and inclinations as a rule of conduct on others, is so energetically supported by some of the best and by some of the worst feelings incident to human nature, that it is hardly ever kept under restraint by anything but want of power; and as the power is not declining, but growing, unless a strong barrier of moral conviction can be raised against the mischief, we must expect, in the present circumstances of the world, to see it increase.
It will be convenient for the argument, if, instead of at once entering upon the general thesis, we confine ourselves in the first instance to a single branch of it, on which the principle here stated is, if not fully, yet to a certain point, recognised by the current opinions. This one branch is the Liberty of Thought: from which it is impossible to separate the cognate liberty of speaking and of writing. Although these liberties, to some considerable amount, form part of the political morality of all countries which profess religious toleration and free institutions, the grounds, both philosophical and practical, on which they rest, are perhaps not so familiar to the general mind, nor so thoroughly appreciated by many even of the leaders of opinion, as might have been expected. Those grounds, when rightly understood, are of much wider application than to only one division of the subject, and a thorough consideration of this part of the question will be found the best introduction to the remainder. Those to whom nothing which I am about to say will be new, may therefore, I hope, excuse me, if on a subject which for now three centuries has been