John Stuart Mill, On Liberty (1859)

Posted: Mon, Mar 2, 2026

Today

  • A new approach [25 min]
  • Thinking through the harm principle through cases
  • Questions about the term paper? [save 10 min]

Mill’s new approach

  • Rejecting the social contract tradition: p. 582
  • Coming out as a utilitarian: p. 567
  • Well-being: But what makes our lives go well? p. 581
    • Rejecting Hobbesian mechanical philosophy
    • The tree metaphor for Enlightenment humanism:
      • What distinguishes us as human beings is our daringness to use our reason to govern ourselves for ourselves.
      • We are not machines; machines work for us.
      • No individual two trees are, or should be, alike.
      • Trees live and thrive in forests—culture and society become proper subjects of political philosophy and normative critique.

Two particular urgent threats in the background:

  • Democracy by majoritarian rule ⇒ threat of moralistic and paternalistic legislation
  • The Industrial Revolution ⇒ pressure to conform like machines ⇒ threat to individuality

Mill’s “one very simple principle”

Statements of the harm principle (pp. 166–67):

  • “whether the means used be physical force in the form of legal penalties, or the moral coercion of public opinion”
    • Cf. p. 582
  • “the sole end . . . is self-protection”
    • Cf. p. 567
  • “the only purpose . . . is to prevent harm to others”
    • Purpose vs. condition?
  • “His own good, either physical or moral, is not a sufficient warrant”
    • But does it count at all?
  • “To justify that, the conduct from which it is desired to deter him must be calculated to produce evil to some one 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.”
    • Self-regarding (part of) conduct: Fully private, not subject to interference, fully one’s own responsibility (“experiments of living,” p. 580).
      • Except voluntary slavery (p. 589).
      • Except children (p. 567).
      • Except “barbarians” (p. 567).
    • Other-regarding (part of) conduct: Subject to interference when justified by considerations of harm to others.
      • Balanced against the nature and severity of the interference: Unlike legal sanctions, moral sanctions are strengthened by others’ self-regarding interests (pp. 583–84).
      • Balanced against the nature and severity of the harm: Breach of “distinct and assignable obligation” (p. 585), corn-dealer example (p. 579).
      • Balanced against the likelihood of the harm: “a definite risk of damage” can be as harmful as “a definite damage” (p. 586).
      • Balanced against societal interests: “for the sake of the greater good of human freedom” (p. 586).
      • When interference is not justified, the conduct is merely an “offense” or “nuisance”—these seem to be terms of art.

Now, some cases

  1. Classic paternalistic legislation: Seat belt, drinking age, recreational drug, and gambling laws.
  2. Classic moralistic legislation: Prohibitions of adultery, fornication, public indecency, miscegenation, same-sex intimacy, and polygamy
  3. Conspiracy theories: Flat earth, climate denial, and microchipped vaccines