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book1859

On Liberty

Disciplines:
political philosophy
ethics

Summary

Mill's On Liberty (1859) is the definitive liberal statement of individual freedom, grounding liberty in the harm principle and defending intellectual diversity as essential to truth.

Core Contribution

Mill argues that the only legitimate basis for coercing individuals is preventing harm to others; thought, expression, and lifestyle choices that affect only oneself are protected absolutely; and the free marketplace of ideas is necessary because we can never be certain our views are right.

Key Spikes & Highlights

  • Harm principle (the only purpose for which power can rightfully be exercised over another is to prevent harm to others)
  • Free marketplace of ideas (suppressing an opinion harms not just the dissenter but society, which loses the chance to correct error)
  • Individuality chapter (Chapter 3 argues that cultivating one's own nature is a positive good, not just a negative freedom)
  • Tyranny of custom (social conformity and pressure to conform are as dangerous to liberty as legal prohibition)

Historical Influences

John Stuart Mill

Intellectual Lineage

Classical liberalism Utilitarian traditionEnlightenment thought

Allied Works

Utilitarianism The Subjection of Women A Theory of Justice

Contemporaries & Peers

Utilitarianism The Subjection of Women Two Treatises of Government

Minds Influenced

No recorded minds influenced.

Intellectual Posterity

Harm principle Free speech defenseLiberal individual rights tradition

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