3: Mill's On Liberty
Avoiding Two Types of Tyranny: The Need for a Principle
Mill's concern in On Liberty (1859) is with "the nature and limits of the power which can be legitimately exercised by society over the individual" (p. 1).
His concern is not with "those backward states of society in which the race itself is in its nonage" (p. 10), but with what he calls a "civilized community" (p.9), i.e. society in developed democratic states, such as Britain and the U.S.
By "individual[s]" he means "human beings in the maturity of their faculties" (p. 9), i.e. adults.
Mill holds that there are two ways in which power can be exercised over the individual, or two different forms that "the tyranny of the majority" (Alexis de Tocqueville's phrase, from Democracy in America (1835 (Vol. I) and 1840 (Vol. II), quoted, p. 4) may take:
(1) "the tyranny of the magistrate" (p. 4), i.e. by law.
(2) "social tyranny" (p. 4), i.e. by "tyranny of the prevailing opinion and feeling... the tendency of society to impose... civil penalties, its own ideas and practices as rules of conduct on those who dissent from them; to fetter the development and, if possible, prevent the formation of any individuality not in harmony with its ways, and compel all characters to fashion themselves upon the model of its own" (p. 4-5
Mill is concerned, in the end, with "legitimately exercised" power, with the "limit to the legitimate interference of collective opinion with individual independence" (p. 5). This is opposed to the illegitimate interference with individual liberty, which is tyranny.
He believes that "Some rules of conduct... must be imposed – by law in the first place, and by opinion on many things which are not fit objects subjects for the operation of law." (p. 5)
So far, "The likings and dislikings of society, or of some powerful portion of it, are thus the main thing which has practically determined the rules laid down for general observance, under the penalties of law and opinion." (p. 7)
So far, "There is, in fact, no recognized principle by which the propriety or impropriety of government interference is cutomarily tested. People decide according to their personal preferences." (p. 8)
The result is, "And it seems to me that in consequence of this absence of rule or principle, one side is at present as often wrong as the other; the interference of government is, with about equal frequency, improperly invoked and improperly condemned." (p. 9)
The Harm Principle
"The object of this essay is to assert one very simple principle, as entitled to govern absolutely the dealings of society with the individual in the way of compulsion and control, whether the means used be physical force in the form of legal penalties or the moral coercion of public opinion. 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... the conduct from which it is desired to deter him must be calculated to produce evil to someone else." (p. 9)
"If anyone does an act hurtful to others, there is a prima facie case for punishing him by law or, where legal penalties are not safely applicable, by general disapprobation." (p. 10)
"Whenever, in short, there is a definite damage, or a definite risk of damage, either to an individual or to the public, the case is taken out of the province of liberty and placed in that of morality or law." (p. 80)
Thus, the law, or private persons, cannot legitimately interfere with a person's liberty if the person is:
(a) not harming himself or others
or is
(b) only harming himself
People may indeed remonstrate with him, reason with him, persuade him, entreat him, to stop. They may also shun him and advise other people to do the same. But if he is doing either (a) or (b) then this is not enough to justify "compelling him or visiting him with any evil in case he do otherwise" (p. 9).
Note that Mill does not here define harm. But it is at least true that the harm must be "tangible, secular, material – physical or financial, or, if emotional, focused and direct – rather than moral or spiritual" (Richard Posner, "On Liberty: A Revaluation", in On Liberty (Rethinking the Western Tradition), ed. David Bromwich (New Haven: Yale University Press, 2003) p. 197)
Legitimate restriction ............................... Illegitimate restriction
Slander ................................................. Giving Offense
Dynamiting competitor's plant ................... Competing by lowering prices or
improving service or product quality
Rape .................................................... Consensual sexual activity
Stopping someone from harming another .... Stopping him from harming himself
Mill thus rejects both:
(i) Hostile interferences with a person's liberty;
(ii) Well-intentioned interferences with a person's liberty.
Justification for Harm Principle
"all restraint, qua restraint, is an evil" (p. 94)
All restriction or curtailment of a person's liberty is, according to Mill, an evil to that person. All restriction or curtailment of a person's liberty, either by a law (legislation by the state) or by society is prima facie wrong. Justification has to be given for each and every restriction or curtailment of liberty, by law or society.
The only justification for restricting or curtailing a person's liberty is that (i) by exercising her/his liberty the person is harming another person [without or against her/his informed consent when he/she is an adult] and (ii) the effect of such restriction or curtailment results in more benefit than harm overall.
Mill does NOT argue that people have a right to liberty. Rather, he argues that granting people liberty will have the effect that utility will be increased (people's welfare will be increased overall):
"I forego any advantage which could be derived to my argument from the idea of abstract right as a thing independent of utility. I regard utility as the ultimate appeal on all ethical questions; but it must be utility in the largest sense, grounded on the permanent interests of man as a progressive being. Those interests, I contend, authorize the subjection of individual spontaneity to external control only in respect to those of each which concern the interest of other people." (p. 10)
Five Liberties
Mill is concerned to defend at least four kinds of liberty as absolute liberties, such that they can never be restricted or curtailed:
(1) Liberty of belief and feeling
(2) Liberty of expression of belief and feeling
(3) Liberty of self-regarding action of any kind
(4) Liberty of consensual other-regarding action of any kind
There is also a fifth kind of liberty:
(5) Liberty of non-consensual other-regarding action
This fifth kind of liberty, Mill argues, is not absolute. It is morally permissible to restrict this form of liberty if two conditions are met:
(a) The exercise of the liberty -- i.e. the action -- harms the other person(s);
(b) The effect of the restriction/curtailment of the liberty, either by another person or by a law, results in more benefit than harm (i.e. greater overall utility).
His argument, then, is that liberties (1)-(4) can never be morally permissibly restricted or curtailed, either by law or by society. One ought to be:
(1) Free to believe and feel whatever one wants
(2) Free to express and publish whatever one wants
(3) Free to do to oneself whatever one wants
(4) Free to do with and to others whatever they freely, knowingly consent to one doing with and to them, and vice versa
However, in the case of liberty (5), when it is a non-consenting other-regarding action that harms another, and when the overall benefit of restriction/curtailment is greater than the cost of restricting liberty, then it is morally permissible to restrict or curtail a person's liberty, either by the intervention of other persons, or by a law. Even here, however, Mill's normal concern is with a law that restricts or curtails liberty, rather than the intervention of other persons (privately).
(1) Liberty of Belief and Feeling
"This, then, is the appropriate region of human liberty. It comprises, first, the inward domain of consciousness, demanding liberty of conscience in the most comprehensive sense, liberty of thought and feeling, absolute freedom of opinion and sentiment on thought and feeling, practical or speculative, scientific, moral, or theological." (p. 11)
= You ought to have the freedom, that is, you ought not to be prevented by the actions of law or society, to believe whatever you want, on any matter whatsoever, and to have any feeling you want, about anything whatsoever.
For example, you ought to be able to believe: "Down with Big Brother" (1984). There should be no such crime as 'thought-crime'. Note that 'there should be no such crime as thought-crime' cuts both ways. Evil thoughts, or anti-liberal thoughts, can't be crimes either.
Mill believes that there are four arguments to support this liberty of belief and feeling:
(1) Perhaps the opinion we would suppress is true
"We can never be sure that the opinion we are endeavoring to stifle is a false opinion.. the opinion which it is attempted to suppress by authority may possibly be true... All silencing of discussion is an assumption of infallibility." (p. 16)
"First, if any opinion is compelled to silence, that opinion may, for aught we can certainly know, be true. To deny this is to assume our own infallibility." (p. 50)
(2) Perhaps the opinion we would suppress is partly true
"the conflicting doctrines, instead of being one true and the other false, share the truth between them, and the nonconforming opinion is needed to supply the remainder of the truth of which the received doctrine embodies only a part." (p. 44)
"Secondly, though the silenced opinion be an error, it may, and very commonly does, contain a portion of the truth; and since the general or prevailing opinion on any subject is rarely or never the whole truth, it is only by the collision of adverse opinions that the remainder of the truth has any chance of being supplied." (p. 50)
(3) We need the false opinion in order to make sure the true opinion is not
held as a mere uncontested prejudice
"if we were sure [that the opinion was false], stifling it would be an evil still" (p. 16)
"however true it [the opposite opinion] may be, if it is not fully, frequently, and fearlessly discussed, it will be held as a dead dogma, not a living truth" (p. 34)
"Nor is it enough that he should hear the arguments of adversaries from his own teachers, presented as they state them, and accompanied by what they offer as refutations. That is not the way to do justice to the arguments or bring them into real contact with his own mind. He must be able to hear them from persons who actually believe them, who defend them in earnest and do their very utmost for them, He must know them in their most plausible and persuasive form; he must feel the whole force of the difficulty which the true view of the subject has to encounter and dispose of, else he will never really possess himself of the portion of truth which meets and removes that difficulty." (p. 35)
"Thirdly, even if the received opinion be not only true, but the whole truth; unless it is suffered to be, and actually is, vigorously and earnestly contested, it will, by most of those who receive it, be held in the manner of a prejudice, with little comprehension or feeling of its rational grounds." (p. 50)
(4) We need the false opinion in order to bring home to ourselves the meaning of the true opinion
"fourthly, the meaning of the doctrine itself will be in danger of being lost or enfeebled, and deprived of its vital effect on the character and conduct: the dogma becoming a mere formal profession, inefficacious for good, but cumbering the ground and preventing the growth of any real and heartfelt conviction from reason or personal experience." (p. 50)
Examples of what people should be free to believe, either because it is true, or partly true, or because it stops us from holding the opposite (true) opinion as a mere prejudice, or because it brings home to us the meaning of the opposite (true) opinion:
(a) All religion is superstitious rubbish that makes life easier for people;
(b) Lee Harvey Oswald was not working alone when he shot JFK;
(c) Women are inferior to men at math and science;
(d) All homosexuals are degenerate animals who will burn in hell;
(e) Certain races are intellectually inferior to others, at least in terms of their performance on standard IQ tests;
(f) The Holocaust is just a myth spreading by lying Jews.
Note: Mill is not saying that none of these beliefs or feelings is to be condemned. Mill is saying that you may not, by law or by society, prevent a person from believing anything, or feeling anything. Everyone ought to be free to have, e.g., offensive, insulting beliefs, and to feel, e.g., contempt and hatred for others, either all others or certain groups (in the sense that neither a person nor a law should prevent them from believing or feeling in that way, by killing them, or drugging them, or beating them up, or any form of coercion.)
You should, however, condemn them for these beliefs and feelings, as much as possible: "Cruelty of disposition; malice and ill-nature; that most antisocial and odious of all passions, envy; dissimulation and insincerity, irascibility on insufficient cause, and resentment disproportioned to the provocation; the love of domineering over others; the desire to engross more than one's fair share of advantages... these are moral vices and constitute a bad and odious moral character" and "are properly immoral and fit subjects of disapprobation which may rise to abhorrence" (p. 76-77).
(2) Liberty of Expression and Publication
"The liberty of expressing and publishing opinions may seem to fall under a different principle, since it belongs to that part of the conduct which concerns other people, but, being almost of as much importance as the liberty of thought itself and resting in great part on the same reasons, is practically inseparable from it." (p. 11-12)
= You ought to have the freedom, that is, you ought not to be prevented by the actions of other moral agents, or by the law, to express in speech or writing whatever you want, on any matter whatsoever, and to publish whatever you want, about anything whatsoever.
Mill himself, however, offers the following rule concerning freedom of expression:
"even opinions lose their immunity when the circumstances in which they are expressed are such as to constitute their expression a positive instigation to some mischievous act. An opinion that corn dealers are starvers of the poor, or that private property is theft, ought to be unmolested when simply circulated through the press, but may [NOTE: "may"] justly incur punishment when delivered orally to an excited mob assembled before the house of a corn dealer, or when handed about among the same mob in the form of a placard." (p. 53)
Mill, therefore, holds that when the expression of a belief or feeling constitutes an instigation to harm others, it may justifiably be restricted.
The following are examples of expressions of belief or feeling that are considered by some philosophers to fall into this category. (However, you may disagree with these philosophers about these examples.)
(a) When expressing myself very loudly would precipitate an avalanche.
(b) When my independent theater workshop, "Mock Bank Robbery #1", looks and seems to everyone in the bank like it is the real thing.
(c) When my expression of my views about someone leads others to form an adverse opinion of her and makes her the object of ridicule or abuse (defamation and the right to a fair trial).
(d) "The most stringent protection of free speech would not protect a man in falsely shouting fire in a theatre and causing a panic. [...] The question in every case is whether the words used are in such circumstances and are of such a nature as to create a clear and present danger that they will bring about the substantive evils that Congress has a right to prevent." [added emphasis]
(Justice Holmes, Schenck v. United States, 249 U. S. Supreme Court 47 (1919)) [Note that Holmes says "falsely". If there is indeed a fire, then one is protected in shouting "Fire!"].
(e) When the act of expression is an order or a threat or when it is a signal between confederates.
(f) "Suppose some misanthropic inventor were to discover a simple method whereby anyone could make nerve gas in his kitchen out of gasoline, table salt and urine. It seems just as clear to me that he could be prohibited from passing out his recipe on handbills or broadcasting it on television as that he could be prohibited from passing out free samples of his product"
(T. M. Scanlon, "A Theory of Freedom of Expression", 1972)
Q: Are they all instigations to harm others?
Q: Would Mill agree that they are permissibly restrictable or curtailable?
(3) Liberty of Self-Regarding Action
Action that is "self-regarding" (p. 13) is action that only involves oneself. A self-regarding action is one that does not involve anyone except oneself in the full description of the action. For example, drinking a glass of water is a self-regarding action.
Other-regarding action is action that involves another person. An other-regarding action is one that does involve someone else in the full description of the action. For example, buying a glass of lemonade is an other-regarding action, since I cannot buy something from myself. (Really the action is "buying a glass of lemonade from someone else".)
One question this raises is the following: if someone else is affected in any way by my performing a self-regarding action, is the action still self-regarding?
So, for example, if I drink a glass of bat's blood, and you watch me, and you become violently sick, is it still the case that my action is self-regarding?
Possible answer: It can be described without reference to you. It is merely a side-effect of my performing the action that you are affected. It is true that feeling nauseous is a harm.
Another question this raises is whether, if the action is self-regarding, may be nevertheless be prohibited because, when carried out in public, it causes offence to others?
Mill says the following:
"Again, there are many acts which, being directly injurious only to the agents themselves, ought not to be legally interdicted, but which, if done publicly, are a violation of good manners and, coming thus within the category of offenses against others, may rightly be prohibited. Of this kind are offences against decency; on which it is unnecessary to dwell, the rather as they are only connected indirectly with our subject, the objection to publicity being equally strong in the case of many actions not in themselves condemnable, nor supposed to be so." (p. 97)
Here Mill argues that self-regarding actions that, when done publicly, are such that they are "offences against others", are such that they "may rightly be prohibited". Some have argued that Mill is contradicting himself here. However, since his position is still that no self-regarding action that is performed in private may be prohibited, he may be said to be avoiding a contradiction.
The point is that the self-regarding / other-regarding distinction is an entirely different distinction from the private / public distinction.
In the case of the liberty of self-regarding actions, Mill's concern is another kind of reaction to self-regarding actions, such as "moral" outrage at self-regarding actions that are conducted in private. If, for example, my self-regarding action conducted in private is such that it "morally" outrages you, then according to Mill, this is never a justification for intervention.
Mill's point here is a strong one. His point is that self-regarding actions in themselves cannot be immoral. No amount of anything that an agent does to himself or herself can be immoral. This is because morality (and hence immorality) requires that there be at least two persons. There are no moral duties to oneself; hence, it is logically impossible, in doing something to oneself, to violate morality. There are only moral duties to others. It is a category mistake to morally condemn self-regarding action; one may only condemn it on non-moral grounds (e.g. that it is stupid). Immorality only begins with others are involved (indeed, only begins when others are harmed without their consent.) Hence anyone who holds that a self-regarding action is immoral fails to understand what morality is. Robinson Crusoe, alone on his island, is simply unable to do anything immoral (leaving aside animals, the eco-system, etc., and assuming that he cannot affect others from a distance).
"A person who shows rashness, obstinacy, self-conceit -- who cannot live within moderate means; who cannot restrain himself from hurtful indulgence; who pursues animal pleasures at the expense of those of feeling and intellect... [...] [these] self-regarding faults... are not properly immoralities, and, to whatever pitch they may be carried, do not constitute wickedness. They may be proof of any amount of folly or want of personal dignity and self-respect, but they are only a subject of moral reprobation when they involve a breach of duty to others. [...] The term duty to oneself, when it means anything more than prudence, means self-respect or self-development, and for none of these is anyone accountable to his fellow creatures, because for none of them is it for the good of mankind that he be held accountable to them." (p. 76-78)
The two kinds of self-regarding actions that normally provoke the reaction that what one is doing to oneself is "immoral" are:
(1) Harms to oneself (e.g. shooting heroin, getting tattoos)
(2) "Perverse", "immoral", etc., self-regarding actions (e.g. masturbation)
Mill is unequivocal in insisting that other moral agents, or the law, are never justified in intervening in self-regarding actions:
"His own good, either physical or moral, is not a sufficient warrant. He cannot rightfully be compelled to do or forbear because it will be better for him to do so, because it will make him happier, because, in the opinions of others, to do so would be wise, or even right. These are good reasons for remonstrating with him, or reasoning with him, or persuading him, or entreating him, but not for compelling him, or visiting him with any evil in case he do otherwise. 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, his own body and mind, the individual is sovereign." (p. 9)
"the principle requires liberty of tastes and pursuits, of framing the plan of our life to suit our own character, of doing as we like, subject to such consequences as may follow, without impediment from our fellow creatures, so long as what we do does not harm them, even though they think our conduct foolish, perverse, or wrong." (p. 12)
Mill's position is that it is morally impermissible, or wrong, to intervene in the case of self-regarding actions. Intervening to stop a person person performing a self-regarding action is an other-regarding action. Since one is, by intervening, restricting her liberty, one is harming her. If her action is self-regarding, then by definition she is not harming another person. She is not harming anyone else, and you are harming her. Your action is not an action of self-defense, or of defending anyone else. You are simply harming someone who is not harming anyone else (except perhaps herself). It is morally impermissible, or wrong, to harm someone who is not harming anyone else (even if she is harming herself).
Of course, Mill has in mind not actions that are self-harming, but actions that are not self-harming (e.g. masturbation, drinking alcohol, reading atheistic books). However, the argument works just as well for actions that are self-harming.
The claim that self-harm must never be prevented is premised on the assumption that the person in question is (a) deliberately intending to harm herself, and (b) is rational and not suffering from condition such that she is not in control of her own actions, and (c) is not acting under duress.
Thus, you may indeed prevent a person from crossing a dangerous bridge when you know the bridge is dangerous, and she does not, and she does not intend to put herself in danger. And you may indeed prevent a person from deliberately crossing a dangerous bridge if she is high on drugs. And you may indeed prevent a person from deliberately crossing a dangerous bridge if someone else is forcing her to cross.
However, if she knows the bridge is dangerous, and is in control of her own actions, and her deliberate action of crossing the dangerous bridge is her own free action, then you may NOT prevent her by holding her back, knocking her out, drugging her, etc. All that you may do is endeavor in any way possible, short of coercion, in preventing her from crossing.
Mill imagines that one argues with her, tries to persuade her, advises her, pleads with her, etc. One might ask, however, whether, e.g., running ahead and smashing the dangerous bridge counts as not preventing her. It is certainly not a form of coercion.
In terms of a law, Mill's argument is that there may not be a law that says, e.g. "Do not cross bridges when you believe it is dangerous". (Assuming that no-one else may be harmed by your crossing a dangerous bridge.)
Here Mill argues against paternalism, or restricting/curtailing a person's liberty for that person's own good. Here "good" is normally understood as physical well-being. This is paternalism proper.
However, there is another kind of good, "spiritual well-being", or "the good of one's soul", that may also be invoked. This may be called "moralistic" paternalism. This is not normally defended by those who defend paternalism proper.
It should be noted that not all paternalistic laws are laws about self-regarding action. Some paternalistic laws (e.g. wear a helmet when riding a motorcycle) do concern self-regarding action. Some laws (e.g. do not gamble) concern other-regarding action.
(a) Paternalistic self-regarding laws: Seat-belt laws, motorcycle and bicycle helmet laws, laws that prohibit swimming at public beaches without a lifeguard present, laws prohibiting children or women to work at certain kinds of jobs, laws prohibiting the use of drugs, laws prohibiting suicide and attempted suicide.
(b) Paternalistic other-regarding laws: Laws requiring people to hold licenses if they seek to practice certain professions, laws prohibiting gambling, laws regulating the rates of interest for loans, laws prohibiting dueling, and laws that prohibit selling oneself into slavery.
Both of these kinds of laws concern paternalism proper.
A further case of laws, for example, e.g. laws prohibiting certain kinds of sexual acts between consenting adults, or laws prohibiting prostitution, may be considered paternalistic laws proper, if one counts them as protecting people from e.g. diseases. However, normally, such laws are there to protect the individuals from "moral" harm. Hence they are "moralistic" paternalistic laws. They are laws against "moral" corruption.
Concerning the case of self-regarding action that "morally" offends or outrages others, Mill is unequivocal that reactions are never a justification of any kind for intervention. In fact, Mill holds that such reactions are utterly confused. How can a self-regarding action be immoral?
(4) Liberty of Consensual Other-Regarding Action
Mill says surprisingly little about such action. He does, however, argue that such action is never to be prevented:
"But there is a sphere of action in which society, as distinguished from the individual, has, if any, only an indirect interest; comprehending all that portion of a person's life and conduct which affects only himself, or if it also affects others, only with their free, voluntary, and undeceived consent and participation... the liberty, within the same limits, of combination among individuals, freedom to unite for any purpose not involving harm to others: the persons combining being supposed to be of full age and not forced or deceived." (p. 11)
This argument protects prostitution (but not, of course, child prostitution or the "white slave trade").
Mill does not discuss the case of people consenting to being harmed by others. For example, if, as in the movie Fight Club, I ask you to hit me, then this is an other-regarding action that is consensual, even though it involves harm. It does seem, however, that Mill holds that such an action can never be prevented by others (so long as those engaged in the consensual harmful activity are doing so deliberately and knowingly and are not under the influence of drugs or duress). Boxing, for example, would be such a case.
(5) Liberty of Non-Consensual Other-Regarding Action
Again, Mill does not normally distinguish simply between an action done to another that the other person consents to, and an action done to another that the other person does not consent to. Mill's concern is with an action done to another that the other person does not consent to and that is harmful. I shall simply refer to this as action that is harmful to another.
"Some rules of conduct, therefore, must be imposed -- [1] by law in the first place, and [2] by opinion on many things which are not fit subjects for the law".
(p. 5)
= Some conduct is to be prohibited by law; some conduct is not fit for prohibition by law, but should be prohibited by [moral] opinion.
"If anyone does an act hurtful to others, there is a prima facie case for punishing him [1] by law or, where legal penalties are not safely applicable, [2] by general disapprobation." (p. 10)
= If an act is hurtful/harmful to others, then it may be the case (i.e. if, in addition, overall benefit outweighs cost) that this act should be criminalized, or, if this is not safely applicable, it may be the case that this act should be [morally] condemned.
It is not enough, then, for an action to be harmful. For there to be a law against it, it must also be the case that restricting or curtailing the liberty of the agent or agents produces more overall benefit.
"There are also many positive acts for the benefit of others which he may rightfully be compelled to perform, such as to give evidence in a court of law, to bear his fair share in the common defense or in any other joint work necessary to the interest of the society of which he enjoys the protection, and to perform certain acts of individual beneficence, such as saving a fellow creature's life or interposing to protect the defenseless against ill usage -- things which whenever it is obviously a man's duty to do he may be rightfully be made responsible to society for not doing. A person may cause evil to others not only by his actions but by his inaction, and in either case he is justly accountable to them for his injury. The latter case, it is true, requires a much more cautious exercise of compulsion than the former. To make anyone answerable for doing evil to others is the rule; to make him answerable for not preventing evil is, comparatively speaking, the exception. Yet there are many cases clear enough and grave enough to justify that exception." (p. 11)
= If there is an act, the doing of which is beneficial to others, and the failure to do which is harmful to others, then the law may require the performance of that act.
However, Mill's argument here is ambiguous between:
(i) It is wrong to fail to prevent harm to others;
(ii) To fail to prevent harm to others is to harm others (and it is wrong to harm others).
Claim (ii) is more contentious. Failure to prevent harm to others, it can be argued, is just that. It is not itself harm to others. It may be wrong to fail to prevent harm to others. Nevertheless, it is not the same as harming others. If I watch a man walk under a falling piano, and I do nothing to help him (for example by shouting or pulling him out of the way), then I have failed to prevent him from being harmed. But have I harmed him? Presumably, I was wrong to fail to prevent the falling piano from harming him. Nevertheless, this does not necessarily entail that I harmed him.
"That principle is that the sole end for which mankind are warranted, individually [2] or collectively [1], 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... the conduct from which it is desired to deter him must be calculated to produce evil to someone else." (p. 9)
Conclusion: The only basis on which anyone may be prevented from acting, or be made to act, either by another moral agent, or by the law, is when that person's action is non-consensually harmful to others, or is a failure to prevent unwanted harm to others.
The argument would go as follows:
(i) It is prima facie wrong to harm someone.
(ii) To restrict a person's liberty is to harm someone.
----> It is prima facie wrong to restrict a person's liberty.
Note that it is only prima facie wrong to harm someone, since, in the case of some harms (e.g. imprisonment of a convicted murderer), it is not wrong to harm the person. This is because the person is question is harming others. His harming others justifies harming him. This is why Mill uses the expression "self-protection".
This argument, when applied to a possible law, would go as follows:
(1) The law, 'Do not do Y', restricts people's liberty to do Y, and hence, harms people.
(2) It is always wrong to harm people unless they are harming others.
(3) Doing Y is either harmful to others, or it is not.
(4) If doing Y is not harmful to others, then, since the law prohibiting doing Y harms people, and since they are not harming others, then the law 'Do not do Y' is not warranted.
(5) If doing Y is harmful to others, but if the overall benefit of having the law 'Do not do Y' is less than the overall cost of having this law, then the law is not warranted.
(6) If doing Y is harmful to others, and if the overall benefit of having the law 'Do not do Y' is greater than the overall cost of having this law, then the law is warranted.
It is important to note that there are cases of harmful actions that it would be worse to criminalize than not. For example, lies (or most lies) may be said to be harmful to others. Thus there could be a law prohibiting lying. But a law prohibiting lying would be disastrous. It would be extremely difficult and expensive to enforce, it would create an environment of fear, it would affect social interactions in a negative way, and so forth (at least, that is the argument; its soundness depends on the truth of those claims). Hence, condemnation of lying is left to morality, not law, except for special cases that can be clearly identified and that are potentially gravely harmful, e.g. perjury in court, or falsely shouting "Fire!" in a crowded theater. As Mill says:
"Encroachment on their rights; infliction on them of any loss or damage not justified by his own rights; falsehood or duplicity in dealing with them; unfair or ungenerous use of advantages over them; even selfish abstinence from defending them against injury -- these are fit objects of moral reprobation and, in grave circumstances, of moral retribution and punishment." (p. 76)
Finally, there remains the question of whether there should be laws that enable me to do things, because otherwise my liberty is restricted.
For example, if it is a restriction of my liberty to prevent me from having sexual relations with other consenting adults, is it a restriction of my liberty that I am not able to marry them? Is the state restricting my liberty by not recognizing homosexual marriage, and by not granting the various rights and privileges that go with marriage?
This is the distinction between negative liberty and positive liberty. Negative liberty is the absence of restrictions. Positive liberty, on the other hand, is the provision of resources, aids, etc., for the exercise of one's liberty. Mill's concern is with negative liberty rather than positive liberty.