Political Philosophy Fall 2022

Mill’s Libertarianism


On Liberty falls into four broad parts:

  1. Introductory: Mill sets out his reasons for writing the book and the abstract propositions he will defend (ch. 1).
  2. Liberty of Thought and Expression: Mill argues for liberty in one particular set of cases, thought and expression (ch. 2).
  3. Liberty of Action: Mill defends liberty for actions in general (chs. 3-4).
  4. Specific policy implications (ch. 5).

Today we will talk about the third and fourth parts: Mill’s defense of liberty in general, rather than liberty for the special case of thought and expression.

In these chapters, Mill makes a case for thinking that individuals should be free to do nearly any self-regarding action, that is, anything that effects only their own lives. His case for liberty of action is similar to his case for liberty of thought and expression. He argues that individuals need to discover things for themselves and that society benefits from the innovations made by people with unusual abilities and tastes.

One point that I will try to make is that Mill goes beyond the obvious points about why individual liberty makes people happy. He rests a lot on cases where individuals make bad choices for themselves. Even then, he says, the utilitarian goal of promoting happiness is best achieved by leaving them at liberty rather than interfering with their choices.

The Harm Principle

In the introductory chapter, Mill says that his project is to find a principle for deciding when society may and may not limit individual liberty. Then he announces what that principle is.

That principle is, that the sole end for which mankind are warranted, individually or collectively, in interfering with the liberty of action of any of their number, is self-protection. That the only purpose for which power can be rightfully exercised over any member of a civilized community, against his will, is to prevent harm to others. (ch. 1, par. 9)

This is known as the Harm Principle. It seems to be quite uncompromising: we are only allowed to limit an individual’s liberty to prevent that person from harming others, period. The most natural understanding of “harm” is an action that makes someone worse off than they would have been without the action.

However, there is reason to wonder if this is what Mill has in mind since he lists several cases in which society can force people to do things for the benefit of others as opposed to preventing them from harming others. Here are some examples of things that Mill thinks the state can force people to do: give evidence in court (ch. 1, ¶11); contribute to the common defense and other public goods (ch. 4, ¶3); offer aid (ch. 1, ¶11); abstain from fixing prices with competing firms (ch. 4, ¶4); sent their children to school (ch. 5, ¶12-14).

The beginning of chapter 4 suggests something different. There, Mill defines “harm” as a violation of an individual’s rights. If that is what he means, it pushes the question back to what rights we have. I think Mill has to choose between two options:

  1. A list of rights drawn roughly from common sense, much like what you find in Locke.

  2. A list of rights derived from utilitarianism, as Mill suggests in chapter 5 of Utilitarianism.

Mill does not go into this. But I think he is rhetorically suggesting the first while actually relying on the second.


One thing that Mill seems pretty clear about is that there is a distinction between actions that harm others and actions that merely offend others. According to the harm principle, society may limit liberty to prevent harmful actions, but it may not do so in order to prevent merely offensive ones. Here is Mill’s argument for this distinction.

But the strongest of all the arguments against the interference of the public with purely personal conduct, is that when it does interfere, the odds are that it interferes wrongly, and in the wrong place.

On questions of social morality, of duty to others, the opinion of the public, that is, of an overruling majority, though often wrong, is likely to be still oftener right; because on such questions they are only required to judge of their own interests; of the manner in which some mode of conduct, if allowed to be practised, would affect themselves.

But the opinion of a similar majority, imposed as a law on the minority, on questions of self-regarding conduct, is quite as likely to be wrong as right; for in these cases public opinion means, at the best, some people’s opinion of what is good or bad for other people; while very often it does not even mean that; the public, with the most perfect indifference, passing over the pleasure or convenience of those whose conduct they censure, and considering only their own preference.

There are many who consider as an injury to themselves any conduct which they have a distaste for, and resent it as an outrage to their feelings; as a religious bigot, when charged with disregarding the religious feelings of others, has been known to retort that they disregard his feelings, by persisting in their abominable worship or creed. But there is no parity between the feeling of a person for his own opinion, and the feeling of another who is offended at his holding it; no more than between the desire of a thief to take a purse, and the desire of the right owner to keep it. And a person’s taste is as much his own peculiar concern as his opinion or his purse.

It is easy for any one to imagine an ideal public, which leaves the freedom and choice of individuals in all uncertain matters undisturbed, and only requires them to abstain from modes of conduct which universal experience has condemned. But where has there been seen a public which set any such limit to its censorship? or when does the public trouble itself about universal experience? In its interferences with personal conduct it is seldom thinking of anything but the enormity of acting or feeling differently from itself (On Liberty, ch. 4, ¶12; breaks in the paragraph added)

Mill’s argument is that the public will get it wrong if they try to regulate offensive thoughts. Why? He draws a distinction between “questions of social morality” and “questions of self-regarding conduct.” He says that the public will generally be right when it comes to social morality because they are affected by their decisions.

However, the public will generally be wrong when it comes to regulating people’s opinions because they are not generally affected by their decisions. Consequently, he believes, we should pay no attention to the feelings of someone who is offended by another person’s opinions.

Individual Benefits of Liberty

Mill is a utilitarian, so he has to show that the extensive individual liberty that he advocates is the best way of promoting utility. He tries to do this by showing that individual liberty benefits individuals and also that it benefits society.

Mill’s first line of arguments for the individual benefits of liberty are pretty much what you would expect. He maintains that individuals will, generally speaking, make choices that make themselves happy. So leaving individuals at liberty to decide what to do is a good way of making them happy. This is probably true but not terribly interesting: anyone could have thought of this so we don’t need Mill’s big brain to make the point.

What I think is most interesting about Mill is that most of the arguments make a case for liberty even when individuals do not make good choices. After all, no one is perfect and we are all subject to well known flaws in our decision making. More importantly, the people Mill is arguing against will typically believe that individuals do not make the correct choices for themselves. Mill side-steps their arguments by maintaining that individual liberty is still superior to the alternatives even when individuals do not choose well.

We will spend most of our time on his arguments for this second point. As I suggested last time, they will fall into two categories. One will concern the benefits of liberty for individuals while the other will concern the benefits for society. Again, the argument has to be that leaving individuals at liberty to act in ways that Mill acknowledges are bad is better than interfering with their liberty, both for the individuals concerned and society at large. How does he make that kind of argument?

Examples: Religious Persecution and Marriage

Here are two examples of the kinds of interference with individual liberty that Mill has in mind.

One concerns the persecution of Mormons in the United States (see ch. 4, ¶22). Mill takes this to be a good example of how intolerant democratic societies can be. He’s right! It is also an episode of American history that is often swept under the rug. It should be acknowledged along with slavery, Japanese internment, the dispossession of Native Americans, and all the rest of the more familiar cases, in my opinion.

The other concerns Mill’s argument that individuals should not be allowed to sell themselves into slavery. (More precisely, the state should not enforce any such contracts.) That seems to run afoul of his idea that individuals should be free to do any merely self-regarding act that they choose. It’s my life, after all, why can’t I spend it as a slave if that’s what I want? I don’t mean to be flip. I could agree to an onerous labor agreement in order to support my family. Or maybe I think it is important to commit myself to a monastic life. These are both things that someone may rationally decide to do.

I think Mill’s idea was that liberty is important for self-development. People who sell themselves into slavery lose the chance at development. Since Mill’s case for liberty rests on its role in individual development, it does not extend to this case. Just to be clear: that is speculation on my part, it is not something that Mill explicitly says.

I also want to point out that Mill was really talking about marriage. He is not actually worried about the widespread use of voluntary slavery contracts. His real target is divorce laws that made it very difficult for women to get out of bad marriages. Here is what the law was like in his time, according to Colin Heydt, the author of the entry on Mill in the Internet Encyclopedia of Philosophy.

(1)  British women had fewer grounds for divorce than men until 1923; (2) Husbands controlled their wive’s personal property (with the occasional exception of land) until the Married Women’s Property Acts of 1870 and 1882; (3) Children were the husband’s; (4) Rape was impossible within a marriage; and (5) Wives lacked crucial features of legal personhood, since the husband was taken as the representative of the family (thereby eliminating the need for women’s suffrage).

Mill is saying that marriage in his time was similar to voluntary slavery. He is arguing that the fact that women enter marriage voluntarily doesn’t make this OK. This is a theme he expanded on in his On the Subjection of Women (1869).

You might agree with his conclusion that the marriage laws were bad but dispute his reasons for saying so. That is, you might think it’s unfair or unequal and not, as he says, that it is inconsistent with women’s liberty.

Key Concepts

  1. The distinction between harm and offense.
  2. Why individual liberty of action makes individuals better off.
  3. Why individual liberty makes society better off.


Mill, John Stuart. (1859) 2000. On Liberty. Edited by Mark C. Rooks. British Philosophy: 1600-1900. Charlottesville, VA: InteLex Corporation.