Brandon Oto
June 2008

Propositional Content as a Millean Defense of Artistic Expression

The philosophical question of the exact bounds, nature, and purpose of free speech and toleration within a modern society is by now a well-trafficked one, and much ink has been spilled regarding important concerns such as, “In a democratic society, where should we draw the line on permitting free expression?” Such debates are focused on fine-tuning the border of a larger issue which presupposes that free speech and expression are good to begin with, which is interesting because there’s no reason why this should be true by default. Conscientious philosophers, going to the heart of the issue, have presented a number of arguments in favor of this view, most of which are couched around negative rather than positive reasons—that is, reasons why limiting free speech is undesirable, rather than why the thing itself is a virtue in its own right. John Stuart Mill (in On Liberty) provided one of the relatively few well-reasoned examples of the latter, arguing that the presence of open speech and discourse in a society allows its members to come to better truths—either aborting their incorrect assumptions for better ones, or adjusting previous beliefs based on the arguments they hear, or simply learning more about our own views by being forced to defend them. In other words, the reason we do not block communication of certain ideas is because their very existence—whether right, wrong, or somewhere in between—tends to improve the quality of our own ideas.
Mill’s argument is a singular one because it suggests an inherent virtue of free communication that is not based on the speaker’s interests (for instance, some notion of an inalienable right to autonomy) but on improving the listener’s ability to come to better information and beliefs. The former is valid in its own way, but difficult to defend, because it fairly quickly boils down to a dogmatic belief in certain moral rights. The advantage of the latter is that it is very easy and fairly objective to see the upsides of everyone having better beliefs, at least within the realm of straightforward facts (“flour and water make bread” is a better belief than “rocks and flowers make bread” because the first is better eating).
There is a somewhat vexing problem posed to the Millean argument for free speech, however, when one applies it to instances of artistic expression. The problem is that the argument seems to only apply to speech that communicates or somehow leads to truths, and by introducing art we make it far from clear that all speech actually does this. If it does not, then it seems unaffected by and immune to the Millean defense. To further expand this point, however, we must invoke speech act theory as pioneered by J.L. Austin.

Speech act theory

In How to Do Things with Words, Austin gives a taxonomy of human expression consisting of a hierarchy of locutionary, illocutionary, and perlocutionary speech acts. A locutionary act is an expression with meaning and content; “It is raining,” “The cat is in the hat,” and “I am named Brandon” are all examples. Illocutionary acts are expressions which have the special property that in stating them (performing their action), we perform an actual act. That is, their essence lies not merely in communicating information but in carrying illocutionary force of some kind. The illocutionary force of the statement “Look out!” is to warn you of a danger, an act just as “verbful” as pounding a nail or dancing a jig. The illocutionary act of “I order you to return fire” is to give an order, just as its locutionary value is to convey that fact—the two are performed simultaneously by the same set of words. Perlocutionary acts are speech acts that generate a certain effect; a banal example would be from the above, as the perlocutionary effect of “Look out!” was with any luck to cause you to be warned (or to cause you to duck). The perlocutionary effect created by an angry tirade might be to insult you or rile you. Note that the perlocutionary act is not quite something I actually do, insofar as it is characterized by its effect, which can be indirect and beyond my control; it would be both ineffective and preposterous to try to take direct charge of the effect by saying, “I insult you!” or “I rile you!” (Contrast this with illocutionary acts, which being inherently incapsulated by their linguistic vehicle could quite reasonably be used to say “I warn you” or “I order you.”)
The specific taxonomy aside, the groundbreaking shift Austin introduced was the notion that speech need not consist only of statements with propositional content—that is, truth-evaluable statements of fact. (That humans can only make remarks like “The sky is blue” and not, for instance, “Drat!” was the tacit assumption within the scholarly ranks of philosophy before Austin, and one whose absurdity becomes so evident upon the most cursory examination of human speech that one wonders whether most philosophers have ever bought a bag of groceries.)
It should be obvious where I am headed here. Mill’s case for free speech assumes that the speech we are bandying about consists of propositional statements, and hence can lead to improving our beliefs, and hence should be protected. However, Austin makes it clear that much of speech—indeed, perhaps the majority—is not actually communicating information as much as it is performing certain apropositional actions. Can the Millean argument be used to defend speech acts with no overt propositional content? If it cannot, then it seems it cannot defend artistic expression, because prima facie a painting or a story is not communicating truth—not in some way that will directly lead to better beliefs on the part of the receiver. Perhaps other arguments could be brought to bear, but we would lose a great deal by sacrificing one of our only explanations of an inherent virtue in free expression. When we suggest that “artistic expression should be protected,” we seem to mean intuitively that there is something good about it, at least as good as other forms of expression and perhaps even more so. At the very least we mean something larger than “censoring artistic expression might have negative consequences,” which is not qualitatively any different from deciding not to censor art because doing so would be an annoying burden on the police force.
I will argue below that Mill’s argument does apply to art, because art does in fact yield truths of the kind we are interested in seeking. It can therefore be defended by the Millean case exactly as strongly as other, more obviously propositional speech.
(A note on language: since other than those explicitly defined, the precise definitions of the terms used here is not germane to the argument, I use interchangeably free speech and free expression, artist and expresser and creator, recipient and viewer and receiver, and so forth. The common meanings for such words can be used; linguistic shenanigans have not been employed.)

Art as speech act

What, then, is the function of a piece of art? First, we must decide what we mean by art, and in order to capture the largest category of meaning we should neither specify a medium nor be too picky about definitions. Therefore we will define art as any instance of writing, visual art, media, performance art, or indeed any act that is created by one person, communicates something to another, and is defined by the expresser as art.
This last point may prompt some dissent, but it seems to fit our intuitive understanding of the word. If John paints on a wall and says it is waterproofing, people will willingly call it home improvement; if John paints on a wall and says it is art, some people may decry it as poor or ugly, others may call it “not art” intending to mean that it is insufficiently “artistic” to merit the term, but in general most would say that it is John’s privilege to imagine his paltry splashes of color as a form of visual art. On the other hand, if John calls it waterproofing and others try to call it art, intuitively we would say that they are finding something he had not intended—they might call it beautiful but probably should not call it a work of art, since that would seem to be “hijacking” his original intention. In a very liberal sense we might call anything art, from a flower to a sunset, but this is extending the term to much further lengths than are helpful here. So we will let the artist label his art, and let his art be whatever he pleases, so long as he actually created it in its unique form.
Already we seem to be suggesting that art is, in some sense, a vehicle for intention. We are quite comfortable with expressions like “What is the artist trying to say with this piece?” or “What does it mean?” This seems to place it both close to and far from the concept of communication, because while it connotes that there is some message to be found in art, it also connotes that the message is vague, unclear, and somehow encoded. More importantly, it is not only unclear on the surface with a concrete meaning somewhere beneath—the unclearness goes all the way to the bottom, and there is no guarantee of ever finding the “true meaning” of a piece of art.
Critics argue further against this notion of “propositional art” by observing that we would be hard-pressed to show how art can be used to clearly and explicitly communicate simple information—presumably a simple task for a medium endowed with propositional power. It would be silly to use a painting to depict the data of a spreadsheet, unless it were simply a painting of the spreadsheet, which we would probably be inclined to call not-art anyway.

“Without propositional content, there is little sense to be made of the claim that the material might promote progress towards the truth: truths come to be known by us through the propositions that express them. . . . not all expressive acts take the form, or have the function, of communicating propositions.” (McKinnon 138)

The usual way to express this criticism is to show that we cannot evaluate the truth value of a work of art. If you say, “God created the Earth in seven days,” and I say, “That’s wrong; here is a drawing of God!”, how do you respond? “That’s wrong”? It seems to be neither wrong nor right, simply beside the point, because it makes no assertion and does not engage in the debate. It is like responding by standing on my head and blowing bubbles.
Furthermore, if we accept that art is somehow an expression of the artist’s intentions, then we seem to run afoul of the entire battalion of scholars and critics, hailing from the school of “New Criticism” and invoking the “intentional fallacy,” who opine that the artist’s intentions are entirely beside the point, and not a valid consideration. Then, following the guidance of the same luminaries, we must also ignore the reader’s role in the work to avoid the “affective fallacy.” On the surface we have simply recognized that the subjectivity of any individual—creator, observer, or other—is not actually a measurable quality in an objective work. Digging deeper, however, it becomes clear that we have managed to completely strip the work of any claim to being a vessel of meaning at all, a move which would damage our efforts so gravely they would never be repaired.
The trouble here is that there are at least two possible identities to a work of art, and only one of them is relevant to the question of free or unfree expression. The first possibility is the identity of a work of craftsmanship, like a well-carved chair. From this stance, we take visual composition classes to improve our abilities, we admire the vocabulary of William Safire as an advanced application, and we scrupulously break down the scansion of a Petrarchan sonnet as an exercise in understanding the technique. This sense of art is mechanical and skill-based, and I am not especially interested in it, in particular because it is not inherently a public process: just as one can carve chairs in the comfort of the home, art produced in this sense need never reach an audience, and few critics would object to art that nobody sees. The second identity, however, is that of a meaning-evoking signal, and this is more complex but the more interesting aspect, and the one we really refer to when we call art art. In any case, this distinction is a necessary one to keep in mind, as we will talk here about art only in the latter sense.
Nevertheless, however, MacKinnon and her philosophical associates have an altogether valid point of objection, and defending the role of art as proposition-bearing (or as I am calling it, a meaning-evoking signal—let us refer to this role as MES for short) runs into several distinct challenges. Let us examine them in order.

Objection 1: Unclearness

As complained previously, can a message claim to be an MES if its meaning is unclear?
The most stringent objection to this comes from the realm of classical logic, where we are awash with propositional statements like “The grass is green” and “I am the Queen of England.” These are, of course, intended to be building blocks for deductive syllogisms, and their simple propositional form is necessary for this.
But just as contemporary philosophers readily point out deductive logic’s general inability to be applied to actual life, we can easily accuse the propositional format of impossible idealism. Even a remark like “The grass is green” is quite debatable should we get haughty about definitions and data-gathering for greenness and this particular grass, and we should be so lucky for this to be the most difficult example. In reality, of course, the statements we deal with in life—even those which do purport to convey information, not just perform one of Austin’s actions—are of far greater complexity and are correspondingly all the more difficult to evaluate.
How would one evaluate a statement like “Within power lies danger”? Examples of assassinated monarchs could be sought from historians, but of course in the end some will inevitably fall to disagreement due to how they interpret the lessons of life and how they understand the claim itself. This is annoying, in that we would prefer the kind of easier evaluability of the green grass claim, but it is the kind of thing we cannot avoid; such statements have flavors of relativism, perhaps some unascertainable elements, and often require subjective judgment, and in the end it is not possible for mere mortals to rule on them definitively. But strictly speaking, definitiveness on the greenness of the grass was philosophically impossible too, and it does not seem like this should nullify our ability to nevertheless move towards the best possible judgment. Even science can formulate a theory it cannot entirely verify; we may call it shaky science, but we do not say that it accomplishes nothing.
In short, these MES-type statements we are so comfortable with in ordinary language (and that logicians are so uncomfortable with) are indeed propositional, but in a loose sense. Perhaps it would be better to avoid the word, lest it run afoul of its strict logical definition, but we are at a shortage for better terms. These statements are truth-evaluable, but behind a kind of skeptical barrier; they concern matters past a certain threshold of complexity, or containing a certain level of relativity, that prevents their ever being conclusively and universally ruled upon. To put it somewhat more flippantly, they can be evaluated for truth . . . but you will never finish evaluating.
In this light, it seems now more reasonable to suggest that a work of art can be both meaning-bearing and also unclear. Even remarking on the greenness of the grass requires some linguistic and contextual interpretation; we need merely scale this up to levels exponentally more challenging, and we have the “statements” that are art. So if we advise freedom of speech in the case of remarks about the grass, surely we should also do so in the case of art.

Objection 2: Ownership

Another problem, perhaps a more compelling one, with allowing art to assert claims is the question of whose claims they are.
It seems implicit but vital to the definition of an assertion of belief or truth that it is linked to the individual proclaiming it. Anything else is somewhat incoherent, for how can one assert on behalf of anyone else? The very notion of me “asserting” indicates that it is I who asserts, and places my credibility and backing behind the claim. Indeed, any assertion I make is also an illocutionary speech act asserting an objective truth, namely that I as an individual hold a certain belief. If I asserted things willy-nilly and they were regularly uncovered as falsehoods—or were patently false to begin with, such as “A is ~A”—I would be perceived either as insane or a liar, because I am failing at the level of perceiving truth, or failing at the level of communicating it, but either way the credibility that makes one listen to my claims has run dry.
When someone makes a libelous statement, or advertises false claims, or incites a mob to riot, the law holds him responsible. We might argue for or against these restrictions on grounds of free speech, but in any case it is clear that we grant ownership of a speech act to the speaker who produced it—just as we grant the same ownership to the producer of other “verbful” actions, such as buying bread, picking roses, or dancing.
Once again, however, this intuitive truth explodes into a mass of contradiction when we apply the standards of speech (or indeed, of any action) to art. Who is responsible for a work of art? Certainly the artist, insofar as he actually produced it, though we could also point fingers of varying size at the woman who commissioned it or the man who exhibited it. However, this is again treating the piece in the sense of craft and not of speech or MES; in the latter sense, we are interested not in who put pen to paper or paint to canvass, but in who bears responsibility for asserting the knowledge claim.
Can this be the artist? By the simplest analysis it should be, but our intuitive understanding of art is more complex. For instance, what responsibility does the recipient bear? Some would say all, for in receiving art I can interpret it to mean whatever I please, and while my interpretation may be debated, it seems impossible to call it wrong. Some would say that it is wrong if it clashes with the artist’s original intentions, but in the modern sphere of artistic criticism this is considered naïve.
It seems much more sophisticated to give sole responsibility of ownership to the recipient, but under the MES theory this also seems absurd. How can I communicate a message without any say in its content? Is this actually a message? If I sent a friend a letter that I suppose to have meaning, but composed it exclusively of Rorschach-style ink blots, would we consider it coherent? Certainly it would seem that I cannot call him next week and complain that he didn’t come by my house with his antique violin as I asked, but much more than that, it would seem that I cannot expect anything I encoded to be received at all; the fidelity of input to output is 0%. Obviously, we would not call this a message, since it transmits no information. Even if my friend later informs me of all the wonderful things he read in my letter, we would still not call it a message, because what he read is not a logical consequence of what I wrote. We are both merely imagining separate letters, with no connection between them.
By this way of thinking, we can either allow the viewer of a painting to interpret it as he wishes, or we can allow that the painting has things to say intrinsically, but not both, because the two possibilities are mutually exclusive.
The solution to this dilemma is not altogether elegant, for it recognizes the natural complexities of the world and particularly of what we call art. Indeed, it recognizes that art itself is inherently a “bad” medium of communication, insofar as it does have low fidelity at each level between artist and recipient; perhaps, in fact, it is these very shortcomings that make it effective for its particular uses, but we will examine that later.
In any case, we break down the artistic process into three steps, admittedly somewhat arbitrary, but the analysis applies regardless. The first step is the artist’s production of the art, committing his ideas into a unique form; the second step is the intermediary stage wherein the art exists in a certain state; the third step is the recipient’s interpretation, where the piece is received and turned back into ideas.
The critical understanding comes when we allow “dilution” at each stage. Much like Heisenberg’s Uncertainty Principle, this is simply the allowance—or rather, the acknowledgement that a certain allowance is unavoidable—of modification and inherent drift in meaning at all three levels. First, the artist may not have a clear and coherent message to present, and even if he does it will not survive the transition to its medium in a perfect translation. (Of course, no means of communication is perfect, until we develop flawless mind-transfer rays, but the expressions of art are admittedly particularly loose; in some sense, this is how we distinguish artistic forms from more mechanical ones.) Some ambiguity is thus introduced. Then the piece must make its way to the recipient, and in doing so it is influenced by any number of variables, such as the environment in which it is presented (the book’s design and typesetting, the gallery’s lighting and curating, the lighting and audience in the theater), the cultural situation in which it is received, and any messages that accompany it (such as advertising or “word-of-mouth” expectations that precede it). Finally, the piece is received by the target, and must be inserted into his worldview, past his perceptual filters, and lodge itself somehow into his matrix of beliefs, prior knowledge, and wordly understanding.
Is it any wonder that the final message may, like a long game of “Telephone,” be wildly different from the original intention? No. Does this mean that there is no transmission of meaning at all? Also no.
Recognizing that a medium of communication is bad, in the sense of fidelity, does not mean that it ceases to be a medium altogether. Even if the artist’s intended message was inchoate or vague to begin with, he set out to create a certain stimulus or environment for thoughts to be created. The recipient does obtain meaning from the artistic vehicle, and this is the point to emphasize, rather than the potential lack of fidelity between this message and the one the artist originally conceived.
Again, it may be helpful to recognize that we are not treading off the map here; this is the same basic nature that is present in all communication, merely at the distant end of the spectrum. In no case do we ever instantiate the exact concepts present in our minds into the minds of another; always we must first translate them into a medium, send that along, and let it be decoded, and at each step there is a loss of fidelity. Generally we hope to minimize this, which is why in a concrete transmission such as a financial report we try to use clear language, a neutral format, and hope that the writer is good (i.e. capable of high-quality encoding) and the reader is good (i.e. capable of high-quality decoding). However, we must always allow “errors” and ambiguity, holes that are created at each stage which must be filled in by the recipient’s own imagination. No medium is a privileged means of “true” communication, and art is no exception.

Objection 3: Nature of message

Finally, we come to perhaps the most organic and confusing objection, which is simply a lack of understanding about what the message within art might be. We have been very free so far with terms, calling it everything from a proposition to a meaning to a truth to ideas to thoughts to content, but this is avoiding the problem. A propositional statement like “It is night” is clear in terms of what it asserts, but a fictional novel is much less so; even if we admit the previously-discussed concepts of allowable ambiguity and joint authorship, just what is the content being extracted here?
We can now examine the term I have coined, the meaning-evoking signal, or MES. Why have I used such curious terminology?
Starting from the end, I use signal to indicate that we are dealing with some vector of communication, but not the tight and concrete type meant to define a message as strictly as possible; it is looser and consciously so. It signals but does not clearly delineate.
Meaning-evoking, on the other hand, gets at the heart of what art is. Its role is to evoke certain notions, sensations, beliefs about the world, and understandings of the truth. To evoke is a process that involves both sender and receiver; the stage must be set in a particular way to create the desired circumstances for understanding, and the recipient must engage in that process actively and blend his previous understandings with the new material in a cohesive way.
What is this meaning that we are evoking? At last, we must make some subjective judgments of the sort that will send art scholars running in angry circles; however, I believe that this is an analysis which will ring true to the nature of art most of us grasp. If this is intuition-mongering, so be it; we are producing only a naturalistic defense of art as we understand it.
The meaning we are after is certain truths about life. These can be great or small; the greater are perhaps more significant, but also more difficult to evoke properly, and indeed it is truths that seem objectively “insignificant” in the grand scheme that are often the most important to us, such as musings on love or death; we are wholly human creatures and our experiences—and priorities—are subjectively human. Nevertheless, the meaning being sought after is invariably a statement about life, and the reason it is not simply asserted as a direct claim is that it is a truth which cannot be reduced to words. We might refer to the emotions produced in us, or try to examine the artistic (craft-based) methods used to create them, but the actual effect of a piece of art that we appreciate is to resonate in a way that is not wholly articulable—for if it were, the art would not be needed. We look at a painting and we feel that it touches upon some inutterable essence of reality that we cannot completely define (though we can hint at it in circumlocutory ways), yet is as true as any proposition. We must recognize certain aspects of this reality, or it will fall flat; this is why some art is meaningless to us, seeming to speak the wrong language. Yet if we have enough common ground that we can anchor the territory of the art in our own mental landscape, then we can find a footing and look through the eyes the artist has offered, and see something as compelling as the truest of facts.
We can now better understand the way the “poor” medium of art serves these ends, for the artist can pour these meanings into his form, and the recipient can dig them out, and it does not especially matter whether these are the same meanings, because the art has still served its purpose for both parties. One gets to speak; the other, learn. Faithful reproduction is not necessary.
Without art, we would find ourselves unable to express these types of meanings. Perhaps it is necessary to the nature of such a medium that it should be so ambiguous and low-fidelity, or perhaps it is merely an unfortunate fact. Whatever the case, we lack another way of evoking these meanings. Art is not the best way, perhaps not even a very good one, but it is the only one; there is no natural language, no combination of concrete propositional claims, which will evoke the same meaning. If we remove art, we perform what Austin would call locutionary disablement: we are removing our ability to say certain things.

An alternate defense: Art as perlocutionary effector

There is an alternative method of defending against the above objections, one that requires returning to Austin; it is less comprehensive, but if Austin’s speech act theory is accepted, simpler.
While we can characterize the actions of art as expressing a locution, albeit a vague one, as we have done above, it may bear fruit to instead identify its function as perlocutionary—that is, art exists as a device to cause certain effects in the recipient. By this way of thinking, it is less correct to imagine a work of art as a message-bearing vehicle itself than as a catalyst or trigger that elicits the correct responses in the mind of the recipient—that is, the art does not actually contain the message, but has the power to instantiate it. This is falls equally well under the heading of a meaning-evoking signal, and may yield a more intuitive understanding of how art overcomes the propositional objections above.
However, it is less than clear how any speech act can create certain beliefs or emotions as a perlocutionary effect without also containing those propositions as a locution. If it does not contain them somehow, in some form within its content, then the statement is merely activating or “reminding” the recipient of something he already has within his understanding, and this seems to be of minimal use in establishing better truths.
But perhaps this is an erroneous way of thinking. Perhaps truths of the sort expressed by art are indeed already present within us, or constructible from existing components, in the same way that the basic truths of arithmetic are known intuitively but the truth of a complex algebraic formula, though it demands no additional concepts, may be difficult to spot. If art is an “instruction set” for a certain internal process—e.g. “Think of something blue” does not actually contain the property of blueness but in most cases should lead the listener to experiencing it—it would seem to accurately function in the propositional role without actually being propositional in the usual sense. It may be an unreliable method to suit this function, but that is nothing new.

Art in the Millean argument

Where do we stand, then, in defending art under the Millean “better truths” defense?
The original concern was that we could not understand how art contained truths at all, or led to better ones, and that Mills’s argument was therefore powerless to defend it. Other arguments might be found, but the loss would be serious. Aside from it being prima facie unclear what the proposition in a piece of art might consist of, it seemed both too unclear and too authorless to count as communication.
It seems we have countered these objections, which leaves us back where we started. Can Mill defend artistic expression? It seems so. The same reasons we would offer to oppose the censorship of public assertions of truth or belief can be used to oppose the censorship of art. It also fails in the same ways, for instance in that we are disinclined to defend both art and assertion that violate certain standards of incitement or libel. (After, we might simply take a clearly libelous remark, market it as “fiction” or write it on a canvass in colorful characters, and this should not change its legal standing.) Indeed, one of the advantages of this analysis is that it places no firm line between art and non-art, which lets us avoid having to define “what is art?” There is no definite distinction in reality, and creating one in law is both infeasible and unnatural. We will also not attempt to separate art that possesses the ability to evoke meaning from that which does not; this is merely the above distinction under new names, and the whole basis of our argument is that the process is too vague and subjective to accept such pigeonholes.
One other consequence of this analysis is that, while art receives the same protections as other speech, it receives no greater protection; no special status is accorded to art merely for being art. This seems reasonable, in that within our analysis we are hard-pressed to say why it should receive any such privilege. The only possible reason that art might be considered more important than other speech is that its “topics,” or the meanings it treats with, tend to be matters particularly important to us, rather than mere banalities. But this is true for all speech that comes into contention; the issue of free speech never arises with simple speech that interests nobody and elicits neither praise nor outrage.
The conclusions to be drawn are simple. Artistic expression of any kind should never be censored except when it manifests in ways that society has concluded should always be prevented, “artistic” or not. (Where these taboo areas are established is a matter not treated with here, although notions like the harm principle are probably good tools; this is the general question of free speech and broader than I aim to address.) The aesthetic value or skill level of a work of art do not factor into consideration. Educational, moral, religious, or political virtues are not relevant, nor are prurience or unpleasant subject matter. Noble or base intentions by the artist are not relevant, nor are potentially deplorable interpretations of the work by certain members of the public.
Art is, perhaps, a unique and fascinating enterprise that can offer great benefits to the world, or even cause great harm. Undoubtedly it can be better or worse in quality, or appeal to different people for different reasons. However, this is all fodder for artists and their fellow travelers; on the question of how and when to censor artistic expression, philosophers must remain mute, stating only that conclusions on this point must be identical to those made for speech in general—no more and no less.

References

Austin, John Langshaw. How to do things with Words. Harvard University Press, 1975.
McKinnon, Catriona. Toleration: A Critical Introduction. Oxon: Routledge, 2006.
Mill, John Stuart. On Liberty. 1859.