On Liberty John Stuart Mill - Published in 1859, John Stuart Mill's On Liberty presented one of the most eloquent defenses of individual freedom in nineteenth-century social and political philosophy and is today perhaps the most widely-read liberal argument in support of the value of liberty. Mill's passionate advocacy of spontaneity, individuality, and diversity, along with his contempt for compulsory uniformity and the despotism of popular opinion, has attracted both admiration and condemnation.

John Stuart Mill, English philosopher, political economist, civil servant and Member of Parliament, was an influential liberal thinker of the 19th century. He was an exponent of utilitarianism, an ethical theory developed by Jeremy Bentham, although his conception of it was very different from Bentham's.