On Liberty

About this book

On Liberty is John Stuart Mill’s essay on how far society and the state may rightly interfere with the individual. It was published in 1859, the same year as Darwin’s On the Origin of Species, and it remains the most widely read statement of the liberal case for personal freedom. Mill dedicated the book to his wife, Harriet Taylor Mill, who had died the year before, and said that it was as much her work as his.

The book has endured because it states one clear principle and then tests it. Mill’s “one very simple principle,” usually called the harm principle, holds that the only purpose for which power can rightly be exercised over a member of a civilized community against his will is to prevent harm to others. Nearly every later argument about censorship, drugs, dress, religion or private conduct has had to take a position on that sentence.

The story

On Liberty is an argument, not a narrative, and it is organized in five chapters. The introduction sets out the problem: as democracies replace monarchies, the old danger of tyranny by rulers gives way to a new one, tyranny by majority opinion and custom. The second chapter, on liberty of thought and discussion, is the most famous. It argues that silencing an opinion is wrong whether the opinion is true, false or partly true, because in each case society loses something by not hearing it.

The third chapter defends individuality as an element of well-being, the fourth sets limits on society’s authority over the person, and the fifth works through applications: trade, the sale of poisons, drunkenness, education, marriage and the growth of state bureaucracy.

Themes and historical context

Mill wrote in mid-Victorian Britain, a prosperous, increasingly democratic society that he feared was also increasingly conformist. He had been raised by his father, James Mill, as a strict utilitarian in the school of Jeremy Bentham, and he kept that framework. On Liberty is a utilitarian defense of freedom: liberty matters because, in the long run, a society that lets people think, speak and experiment with ways of living does better than one that does not. Mill does not appeal to natural rights.

The book was controversial from the start, and philosophers have argued ever since about whether the harm principle can be applied consistently, what counts as harm, and whether Mill’s own exceptions (children, the “backward” societies he excluded, and various cases in chapter five) undermine the rule. Those debates are part of the reason the book is still assigned. It is short enough to be read whole and clear enough to be argued with.

Mill was writing before the modern welfare state, before mass media and before most of the twentieth century’s experiments in censorship and propaganda. Readers will find that some of his examples are dated while the questions are not.

Who should read it

On Liberty is about 50,000 words and can be read in a few sittings. Mill’s sentences are long but orderly, and he signposts his argument carefully, so the book is more approachable than most nineteenth-century philosophy. Readers with no background can begin with chapter two on its own. Those who go on to his Utilitarianism and The Subjection of Women will see the same method applied to ethics and to the position of women.

Edition notes

The Project Gutenberg edition was produced by Curtis Weyant, Martin Pettit and the Online Distributed Proofreading Team.