Mill on Liberty of Thought and Discussion

Of course, Mill was not the first author to defend freedom of thought. John Locke upheld a “perfect freedom” of all men to order their actions as they think fit. Locke’s friend Anthony Collins wrote in 1713 that “we have a right to know or may lawfully know any truth. And a right to know truth whatsoever implies a right to think freely.” John Milton argued that God does not “captivate [man] under a perpetual childhood of prescription, but trusts him with the gift of reason to be his own chooser.” But these earlier authors still defended limits on inquiry. Freedom of thought was needed within the space of religious dogmas assumed to be true. Freedom to question the key religious doctrines themselves, as opposed to interpretations of them, was not in the cards. They implied that it would be perverse of us, even paradoxical, to question the very God that entrusted us with the freedom to question matters.

Perhaps influenced by Rene Descartes, Mill defends the freedom to question everything. He is most famous for what we now call the Harm Principle: “[T]he 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. His own good, either physical or moral, is not a sufficient warrant” (68). Questioning received opinions does not constitute harm to others, and people should be free to hold opinions which may harm themselves.

How does Mill arrive at this “one very simple principle,” and how do we distinguish the harms this principle covers from mere “hurts” which may permissibly set back some people’s interests? Though he sometimes uses the language of rights, Mill is not a natural rights proponent: “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” (70). Note that Mill means “progressive” as voluntary and experimental efforts to improve oneself and society, as contrasted with American political Progressivism, which advocated for widespread state intervention to “improve” society according to the opinion of experts, coercively if need be.

Mill is best read as a rule utilitarian advocating for the maximization of mankind’s moral development and diverse excellences beyond simple pleasures or preference satisfaction. We evaluate the rightness or wrongness of rules rather than individual actions because, as F. A. Hayek observed, we are rule-​followers as much as we are goal-​pursuers. We should follow those rules which tend to allow the promotion of human excellence better than alternative rules. Such rules allow promotion of these goods while also providing peace of mind and stability of expectations, unlike an “act utilitarian” approach that may permit numerous unforeseeable interventions which undermine our ability to form long-​term plans.

Mill focuses here on rules that foster the ability of mankind to seek truth in normative matters. These include principled respect for freedom of conscience, liberty of pursuits, and freedom of association. Interfering with or socially oppressing such freedoms are wrongful infringements, and thus material not dignitary harms. By contrast, a “hurt” that merely sets back another’s interests or offends their sensibilities, but without violating any rightful moral claims, doesn’t rise to the level of what most serious versions of rule utilitarianism would regard as warranting prevention. A company may be hurt by losing business to a more efficient or in-​demand competitor, but a rule which requires that we protect companies from losing business would create severe economic inefficiencies detracting from the overall good that the rules of a free market best allow. Likewise, a rule which requires that we never offend others would be unworkable.

While Mill focuses on individuals, his gaze is never far from collective harms: “[T]he peculiar evil of silencing the expression of an opinion is that it is robbing the human race, posterity as well as existing generations, those who dissent from the opinion, still more than those who hold it. If the opinion is right, they are deprived of the opportunity of exchanging error for truth; if wrong, they lose, what is almost as great a benefit, the clearer perception and livelier impression of truth produced by its collision with error” (76, emphasis added). More on these matters below.

Tolerance of different religions or ways of life is often practiced begrudgingly, in recognition that it’s more practical to “live and let live” than engage in constant battles with those who disagree. But this attitude reflects a sort of strategic resignation among parties roughly equal in power, a mere modus vivendi, rather than a principled commitment to respect for other persons. Mill recognizes that this is a thin reed and aims to justify the virtue of tolerance as a passionate commitment to respecting the sovereignty of every individual’s conscience, regardless of how much social power one might otherwise have. Once certain views gain social dominance, for better or worse, the “disposition of mankind, whether as rulers or as fellow citizens, to impose their own opinions and inclinations as a rule of conduct on others is so energetically supported by some of the best and by some of the worst feelings incident to human nature that it is hardly ever kept under restraint by anything but want of power.” (73).

Free thought in search of truth requires engagement with all relevant information and reasons. “Relevant” need not mean “truth conducive.” Explicit or propositional knowledge is often a matter of justified true belief. To be justified—and to know that one is justified—one must have undefeated opinions. To have undefeated opinions, one must have access to relevant contrary arguments and views that one’s undefeated opinion can defeat. This process is fallible and open-​ended. Someday an unforeseen argument might defeat one’s own opinion. But that access and open-​ended process require discussion and exposure to diverse viewpoints and perspectives. A single mind, or a like-​minded group, probably can’t anticipate by itself all competing opinions due to evaluative bias and informational limits. We need interlocutors who think differently in order to challenge (and possibly overrule) some of our current views at a given time. The best chance for maximal exposure to contestation is to allow free association among diverse agents. Free association entails free movement. Just as censorship directly blocks sources of contestation, thus limiting one’s ability to explore potential defeaters, restriction of movement hinders the ability of people to have the fullest interactive access to other perspectives.

By contrast, nobody can claim the privileged epistemic authority to thwart opinions they deem unworthy or dangerous. Everyone knows they are fallible, but “few think it necessary to take any precautions against their own fallibility” (77). Those who desire to suppress an opinion are not infallible and so lack authority to decide the question for all mankind while excluding “every other person from the means of judging.” To suppress an opinion they are sure is false is to assume that their felt certainty “is the same thing as absolute certainty.” All silencing of discussion is an assumption of infallibility” (77). Clearly, feelings don’t make it so.

Given our proneness to error, does this mean we can’t act until we have certainty? If so, wouldn’t that paralyze our ability to take any actions should the views on which they rest turn out to be false? Not so, Mill replies. Of course, we can’t wait until we have absolute certainty to perform any actions, since that would be mass suicide, but it doesn’t follow that all views about how to act are on equal footing. He distinguishes between presuming an opinion to be true because it has survived refutation from every attempt to contest it “and assuming its truth for the purpose of not permitting its refutation.” Complete liberty of disproving our opinion is the very condition which justifies us in assuming its truth for purposes of action, and “on no other terms can a being with human faculties have any rational assurance of being right” (79). Opinions must earn their status as true through exposure to dissent.

How do we identify whose opinions we can trust when truth can be so elusive? Mill suggests we pay attention to a person who has “kept his mind open to criticism of his opinions and conduct. Because it has been his practice to listen to all that could be said against him” (80). The opinions of those willing to engage in good-​faith discussion and debate will tend to be, if not always closer to the truth, more trustworthy as markers of its sincere pursuit. By contrast, those who defend opinions by rooting them in mere sectarian prejudice or custom (e.g. “This is how our group has always done things!”) have no response to others who defend a conflicting set of opinions, even when rooted in their own set of prejudices and customs. Those who aren’t open to criticism of their views have no way of assuring themselves, let alone us, that those views are justified. Simply asserting certainty or truth, while shutting down dissent, won’t work because anyone can do the same with innumerable conflicting opinions. Certainty is the conclusion of hard-​fought engagement with dissent: “To call any proposition certain, while there is anyone who would deny its certainty if permitted, but who is not permitted, is to assume that we ourselves, and those who agree with us, are the judges of certainty, and judges without hearing the other side” (81).

At this point, one might reply to Mill that the opinions best suited for regulating society have more to do with their usefulness than their truth. Allowing people to question the veracity of these useful opinions or customs risks undermining their crucial role in maintaining social order or stability. Plato even suggests “noble lies” may be necessary to promote social harmony and persuade people of their place in the “natural” hierarchy. Mill undercuts such appeals by noting that the “usefulness of an opinion is itself a matter of opinion—as disputable, as open to discussion, and requiring discussion as much as the opinion itself.” We disagree not only about what is useful, but why a given opinion may or may not be useful, depending on the ends which it serves. Just as nobody has a monopoly on truth as such, nobody has a monopoly on the truth about what is useful or counterproductive: “There is the same need of an infallible judge of opinions to decide an opinion to be noxious as to decide it to be false, unless the opinion condemned has full opportunity of defending itself” (82).

Some authors, such as Samuel Johnson, believed that freedom was not necessary for finding truth because truth always prevails in the end despite opposition. For instance, Christianity eventually dominated Europe after overcoming persistent and repeated efforts to suppress it. But Mill cautions against generalizing from particular cases, especially if this tempts one to believe that tyranny can only hinder the pursuit of truth but never destroy it. Experience refutes “the pleasant falsehood” that truth always triumphs over persecution (89). He cites a number of heretics who were martyred by the authorities, whose views would never again see the light of day. Such tyranny has a chilling effect on those who might otherwise challenge orthodoxy: “The greatest harm done is to those who are not heretics, and whose whole mental development is cramped and their reason cowed by the fear of heresy. Who can compute what the world loses in the multitude of promising intellects combined with timid characters, who dare not follow out any bold, vigorous, independent train of thought, lest it should land them in something which would admit of being considered irreligious or immoral?” (95). Roads not taken leave us with what is never seen.

Mill adheres to the dictum that what one thinks, while important, is less important than that one thinks. A great thinker must recognize that “it is his first duty to follow his intellect to whatever conclusions it may lead,” and Mill insists that truth gains more by “the errors of one who, with due study and preparation, thinks for himself than by the true opinions of those who only hold them because they do not suffer themselves to think” (95). This claim extends to the importance of lesser intellects thinking for themselves, rather than deferring in a servile fashion to the opinions of those whose motives may be nefarious.

Thought and discussion also don’t cease to be open-​ended processes in a world where we may have arrived at many or all relevant true opinions. Even here, he who refuses to admit his opinion might be false still “ought to be moved by the consideration that, however true it may be, if it is not fully, frequently, and fearlessly discussed, it will be held as a dead dogma, not a living truth.” Truth held dogmatically “is but one superstition the more, accidentally clinging to the words which enunciate a truth” (97). Mill famously quips, “He who knows only his own side of the case knows little of that.” While a person’s reasons may be good, and no one may have been able to refute them, he has no ground for preferring either opinion “if he is equally unable to refute the reasons on the opposite side” or even know what those reasons are (98). Moreover, he must hear adversarial arguments from persons who believe them, who defend them in earnest, because sincere dissenters are better placed to offer reasons he can’t anticipate on his own (99).

So far, the discussion has treated truth and falsehood as binaries, but Mill observes that in many (perhaps most) cases, opinions and doctrines are partially true and partially false: “when the conflicting doctrines, instead of being one true and the other false, share the truth between them … the nonconforming opinion is needed to apply the remainder of the truth of which the received doctrine embodies only a part” (108). Here again, only through diversity of opinion is there “a chance of fair play to all sides of the truth” (111).

Mill emphasizes the value of actively engaging with justified and true opinions because dogmatically accepting them keeps them from connecting with the inner life of the human being. Passive acceptance brings no lively apprehension of the truth, as “both teachers and learners go to sleep at their post as soon as there is no enemy in the field” (105). Knowledge for Mill is not an end itself but a means for improving oneself and society. Lively apprehension must be exercised through continual thought and discussion about the opinions one holds. Otherwise, these opinions will tend to atrophy like unexercised muscles, and one will be less motivated to feel their truth viscerally and less eager to apply them in creative and entrepreneurial ways.

George H. Smith observes a similar argument in Milton’s Areopagitica, where liberty is defended as the best “school of virtue.” Milton “contended that virtue and vice flowed from the same source, namely, the inner dispositions of the individual and that dispositions are ultimately determined by the judgments of reason.” Because reason is the seat of man’s moral agency, an action can be deemed virtuous only insofar as it flows from a free, uncoerced choice. The “trial of virtue” requires a free society in which individuals are free to form their own judgments and learn from their mistakes. Mill would likely agree that people forced by custom or opinion to live in ways they wouldn’t freely choose are deprived of the ability to be virtuous in any sense, religious or secular.

Finally, Mill recognizes that free discussion will often result in discord rather than harmony, especially if people are emotionally invested in their opinions: “I acknowledge that the tendency of all opinions to become sectarian is not cured by the freest discussion, but is often heightened and exacerbated thereby.” His main interest, however, is not that we try to convince partisan interlocutors who vehemently disagree—or “own” them in a debate—but to demonstrate to calmer and disinterested bystanders “that this collision of opinions works its salutary effect” (115). Mill may have anticipated the increased distrust and polarization we see today when he warned that the “worst offence of [intemperate discussion] which can be committed by a polemic is to stigmatise those who hold the contrary opinion as bad and immoral men” (117).

Of course, all of this discussion presupposes a personal commitment both to finding truth and letting others engage in their own search. But do significant numbers of people really care about subjecting their views to scrutiny? Many people instead invest in a view (or personality cult) and then retrofit their other beliefs to accommodate these. Searching for truth is hard and takes strenuous effort. We must acknowledge “rational ignorance”: Most people may be busy enough with other affairs that they lack the time and resources to engage in comprehensive Millian justificatory exercises. Faith in authority or the prevailing perceived consensus rather than free thought is easier in terms of effort and social acceptance. While there may be no decisive argument for why we should all seek truth continually, Mill offers powerful and undefeated arguments for why we ought not hinder those who do seek it. For the purposes of On Liberty, he may have little concern for those people content to follow custom or received opinion without question. But he would likely still counsel toleration of their freedom not to think, precisely because no belief, let alone justified true belief, can be forced on a mind.

What about clearly false and offensive opinions? Unlike merely false opinions, these may have no epistemic value, not even as contrasting elements by which to test one’s own justifications. It’s not clear how entertaining a racial slur or blood libel can serve as ways to strengthen one’s own arguments in collision with error. If such utterances serve no epistemic value, why should they be protected on rule utilitarian grounds when the offense or hurt they cause may far outweigh any conceivable benefits? Strictly speaking, they may not violate the Harm Principle, but they don’t seem to fit Mill’s arguments for protecting false opinion either.

Mill may have two responses. First, even use of vile speech can remind those who condemn the views motivating it to stay vigilant about maintaining the best arguments against such views. This is not in order to convince those who say vile things, who might never revise their behavior and opinions, but instead bystanders who risk being taken in by racist or anti-​Semitic invective. Second, allowing those with detestable opinions to speak freely shines light on them, providing the rest of us opportunities to condemn or at least be wary of such figures. We may want to know who the jerks are so that we can act accordingly. Besides, forbidding vile speech does nothing to address the sentiments or ignorance behind this speech. If anything, it may just drive those views underground and leave us ignorant of hate sources.

Before concluding, we should note an unfortunate passage that bears mentioning: “Despotism is a legitimate mode of government in dealing with barbarians, provided the end be their improvement … Liberty, as a principle, has no application to any state of things anterior to the time when mankind have become capable of being improved by free and equal discussion” (69). This passage is hopefully more of an anomalous reflection of Victorian bias than Mill’s settled view. Regardless, nothing in the larger arguments of On Liberty commits him to this opinion. Regarding entire peoples as young children needing improvement is clearly mistaken and groundless. Furthermore, if we understand the capability of improvement as a continuum rather than a bright line—which I gather any sensible theories of developmental psychology would—then the opposite of despotism is needed to help young and immature people develop the skills that allow them to fully think for themselves. That can’t magically start at some arbitrary point in time but must be fostered through a liberal education reflecting each youth’s rate of maturation.