I. THE FAILURE OF THE TREATISE

The year 1740 was a disappointing one for David Hume. After leaving the University of Edinburgh at the age of fourteen or fifteen, and overcoming a severe crisis of philosophical confidence in his late teens, Hume had spent nearly all of his twenties conceiving, gestating, and finally delivering through the press his Treatise of Human Nature—only to witness a stillbirth, as the work on which he had labored for so long “fell dead-born from the Press.” When the first two volumes of this self-consciously ambitious attempt “to introduce the experimental Method of Reasoning into Moral Subjects” appeared in 1739, Hume eagerly awaited the response of the learned public and actively solicited the opinions of respected intellectual friends, in some cases sending or presenting copies.Footnote ⁵ The response to this publicity campaign was utterly underwhelming. Reviews of the Treatise were dilatory, few, and dismissive in tone, tending to berate the author for his obscurity rather than engage with his reasoning.Footnote ⁶ Even well-wishing friends were sometimes unable to follow Hume's arguments. By the time Hume published the third and, in the event, final volume of the Treatise over a year after the first two, in 1740, he had already begun the rearguard action that was to culminate in an almost total repudiation of the Treatise in later years, assuring readers in the advertisement that “tho' this be a third volume of the Treatise of Human Nature, yet 'tis in some measure independent of the other two, and requires not that the reader shou'd enter into all the abstract reasonings contain'd in them.”Footnote ⁷

The failure of the Treatise frustrated and demoralized Hume for three different reasons. First, the work was, metaphorically, his baby. At the time, he had dedicated nearly a third of his life, in one form or another, to the creation of the Treatise, and he was deeply invested psychologically in its fortunes. Hume's reviewer in The History of the Works of the Learned complained sarcastically that the Treatise “abounds throughout with Egotisms” and that the “Author would scarcely use that Form of Speech more frequently, if he had written his own Memoirs.”Footnote ⁸ The pronoun “I” is indeed ubiquitous in the Treatise. To a certain extent, the first person singular represents the inquisitive epistemologist experimenting on himself: “Upon opening my eyes, and turning them to the surrounding objects, I perceive many visible bodies; and upon shutting them again, and considering the distance betwixt these bodies, I acquire the idea of extension.”Footnote ⁹ But often Hume's “I” is the brash know-it-all, zealously proselytizing a new doctrine: “This argument I esteem just and decisive,” Hume says of his argument for identifying pride and beauty with pleasure, “but in order to give greater authority to the present reasoning, let us suppose it false for a moment, and see what will follow.” A restatement ensues, then the confident pronouncement that Hume's “system, then, seems already sufficiently confirm'd by experience; tho' we have not yet exhausted all our arguments.”Footnote ¹⁰ At every turn, the language of the Treatise betrays just how deep the author's investment is in his ideas, and how strongly he believes in himself.Footnote ¹¹ The rhetoric of the Treatise (and its eagerness to convince makes it nothing if not rhetorical) is confident, even blustering. Hume wears his mind on his sleeve.

Further, the years of study and thought which the Treatise represented were a vocational investment in addition to a personal one for Hume, a younger son of gentle birth whose income of about fifty pounds a year he hoped to supplement by the profession of letters. Hume had studied the law but disliked it, and a foray into the mercantile world of Bristol in 1734 had lasted only a few months. Hume's surviving correspondence from the mid- to late 1730s does not show him worrying excessively about money per se, and he never knew the true writer's indigence experienced by contemporaries like Samuel Johnson, but it certainly contains, intermingled with and linked to discussions of philosophical ideas, periodic anxiety about developing a career, which would bring with it not only income but also an identity in the world: “I have a great inclination to go down to Scotland this spring to see my friends, and have your advice concerning my philosophical discoveries,” he tells Henry Home in 1737, while negotiations with the printers of the Treatise were under way,

In a letter to his trusted childhood friend Michael Ramsay, written just a month after the Treatise's publication, Hume makes it explicit that he sees his book as the key to his future:

The words Hume uses for what he wants from his philosophical work, “settlement,” “fortune,” and “footing,” cover both economic security and a stable place in hierarchies of rank and class. The indifferent reception of the Treatise, despite the fifty pounds he had been paid for the first two volumes, thus left Hume at a loss.

The final, and perhaps most important, reason for Hume's deep disappointment in the failure of the Treatise to gain popular success lay in the arguments contained within the work. For Hume, “vivacity” is a crucial criterion for belief, and thus for truth. The correctness of an argument is inseparable from its ability to be vividly present to a reader or listener:

Any attempt to discern the truth that goes beyond pure logic, i.e. any “probable reasoning,” is to be judged by the influence it exercises over human feeling. “Sentiment,” placed here between “taste” and “philosophy” just as it hovers ambiguously between the structural pillars of “impression” and “idea” throughout Book I, is a crucial term.Footnote ¹⁵ Associated with both “emotion” and “judgment,” “sentiment” is the term that Hume uses to suggest that the two are ultimately cognate. It follows that if Hume is unable to present his empirical ideas in a way that his readers can follow and respond to, those ideas are not true. Or, as he puts it in the advertisement to the first two volumes of the Treatise, “The approbation of the public I consider as the greatest reward of my labours; but am determined to regard its judgment, whatever it be, as my best instruction.”Footnote ¹⁶

This connection between vivacity and belief, between rhetoric and truth, with “sentiment” as the mediating term, runs throughout Hume's thought. His 1734 “Letter to a Physician,” one of his earliest and most revealing accounts of his philosophical development and method, describes deep anxiety about his perceived failure to present his ideas so as to make a powerful impression:

In 1740 Hume published a sixpenny Abstract of his Treatise, hoping to stir up conversation and promote sales. As such, it represents a homology between Hume's marketing tactics and his epistemology: making the arguments of the Treatise “intelligible” to readers—the Abstract's avowed purpose—will both promote sales and make the arguments of the larger work more believable; that is, so to speak, more true. Given the short compass of thirty-one pages, Hume is explicitly selective about which arguments of the Treatise he will attempt to summarize: he discusses ideas and impressions, causation and custom, belief, substance, infinite divisibility, and (very briefly) the passions and free will. Vivacity and its importance to belief are given central placement, with “sentiment” again linking the emotional realm of “feeling” to the epistemological realm of “belief”:

Hume's commitment to the epistemological importance of vivacity also makes his later phrase “dead-born from the press” an appropriate epitaph for the Treatise; as G. B. Hill observed, Hume's expression is a quotation from Pope's Epilogue to the Satires, in which the poet concludes a series of Horatian imitations by reflecting on the power of satire to bring otherwise unaccountable public figures to justice:

The Treatise is written in a completely different genre than Pope's Satires but mutatis mutandis the principle that “all but truth” is ephemeral applies equally well to both. Hume's allusion to Pope in My Life shows that even at death's door he continued to hold the view that success with readers, the vivacity and intelligibility with which a philosophical work creates belief in the reader, is not merely a question of profit or prestige, but also bears fundamentally on whether the work in question is “truth.”

II. THE ESSAYS AS ESSAYS

The Treatise has, of course, achieved canonical philosophical status in our own century; no doubt the callow, excited Hume who sold the first two volumes to the publisher J. M. Noon for fifty pounds and a dozen copies would feel that both his effort and his doctrines were vindicated could he see his work in print and receiving the meticulous and reverent attention of numerous philosophers and intellectual historians today.Footnote ²⁰ But the modern importance of Hume, and of the philosophical Hume of the Treatise in particular, should not prevent us from observing that when it became clear that this work had not found the understanding audience that he had hoped for and expected, Hume declared it a failure, disparaged it in later years as a piece of premature juvenilia, and promptly set about transforming and restating his ideas in forms which ultimately achieved great contemporary success, among both intellectual elites and the reading public as a whole. It is this transformation and restatement, representation as re-presentation, that I wish to examine by turning to Hume's Four Philosophers essays, “The Epicurean,” “The Stoic,” “The Platonist,” and “The Sceptic.”

If Hume's Treatise suffered popular neglect in his own time, the works that immediately followed it (and were partially composed contemporaneously with it), the Essays, Moral and Political, are little analyzed today; no true scholarly edition exists, for example.Footnote ²¹ These Essays were published, at Edinburgh, in two volumes, which appeared approximately a year apart in 1741 and 1742; the first volume went into a second edition within six months. The Four Philosophers were essays 6–9 in the second volume, which appeared in January 1742, old style.Footnote ²²

In a sense, the rise to scholarly eminence of the Treatise and the descent into obscurity of the Essays are equally unsurprising. The Treatise was a long and complex book by an anonymous author, and one whose claims seemed to threaten basic tenets of Augustan theology and common sense; many of Hume's Essays, in contrast, are given over to a sort of light Addisonian banter which has been out of favor with the English-reading public since well before the turn of the twentieth century. There is evidence, however, that Hume regarded the Essays as complementary and even continuous parts of the same project as the Treatise. The advertisement to the first two volumes of the Treatise promises that their account of “the subjects of the understanding and passions” will be followed, if the author “should have the good fortune to meet with success”, by “the examination of morals, politics, and criticism.” In the event, of course, only the third volume, “Of Morals,” was published. But since politics and criticism form much of the material of the 1741–2 Essays, it is certainly plausible that Hume recast the anticipated later volumes of his Treatise into essay form. Furthermore, the four-volume collection Essays and Treatises on Several Subjects, which Hume published in 1753–4 and republished eight further times before his death, combines the 1741–2 Essays with the Enquiry Concerning Human Understanding and the Enquiry Concerning the Principles of Morals, from 1748 and 1751 respectively, which are themselves more explicit rewritings of the first two volumes of the Treatise.Footnote ²³ Over the course of his career, in other words, Hume clearly came to think of the essay as his generic vehicle of choice for practicing philosophy—and, like Walt Whitman, he assembled his accumulating works into a rolling, agglutinative collection.Footnote ²⁴

Even by the standards of Hume's 1741–2 essays generally, the Four Philosophers essays have received little critical attention.Footnote ²⁵ For eighteenth-century readers, however, they were seen as part of Hume's larger philosophical, as distinguished from merely critical or political, oeuvre; thus the 1758 French translation of the Enquiries Concerning Human Understanding also included “Les Quatre Philosophes du même Auteur” at the end of the second volume.Footnote ²⁶ Reading these essays not as marginal or ephemeral finger-pieces but as truly Humean philosophical compositions, with the same claim to attentive analysis as his better-known works, shows how these essays work together as a group to further the philosophical project both undertaken in the Treatise and continued in the Essays and thereafter, using contemporary generic conventions and expectations to present at least some of Hume's more abstruse ideas in a form that allowed him to secure the popular audience which both his pride and epistemological commitments had led him to hope for with the Treatise.Footnote ²⁷

By calling his moral, political, aesthetic, and epistemological texts “essays,” Hume locates them within an eighteenth-century generic context which was anchored by Addison and Steele's Spectator but saw itself as part of a rhetorical and belletristic tradition descended from Cicero and other classical touchstones.Footnote ²⁸ Hume's advertisement to the first volume of Essays Moral and Political claims that most of his essays “were wrote with a View of being publish'd as Weekly-Papers, and were intended to comprehend the Designs of both the Spectators and the Craftsmen,” i.e. the belletristic and the political.Footnote ²⁹ Though Hume's essays were not in fact published periodically, his volume recalls multivolume editions of essays like the Spectator.Footnote ³⁰ “Of Essay-Writing,” the programmatic essay which begins the 1742 volume of Essays Moral and Political in which the Four Philosophers were first published, finds the narrator describing himself as “a Kind of Resident or Ambassador from the Dominions of Learning to those of Conversation,” i.e. a popularizer of “the higher and more difficult operations of the mind”—like the Treatise.Footnote ³¹ Hume is here consciously adopting the mantle of the Spectator, who resolved to bring “Philosophy out of Closets and Libraries, Schools and Colleges, to dwell in Clubs and Assemblies, at Tea-tables, and in Coffee-houses.”Footnote ³²

Hume's Essays Moral and Political as a whole represent a continuation and expansion of Addison and Steele's project. The “Philosophy” of the Spectator is primarily ethical and aesthetic in scope, organizing its adjustments of etiquette and considerations of the eighteenth-century good life around a Christianized set of neoclassical concepts well summarized by the word “decorum.” Spectator 104 is helpfully representative: Steele cites Cicero's judgment that “Virtue and Decency are so nearly related, that it is difficult to separate them from each other but in our Imagination,” and then mobilizes this authority to condemn women who wear masculine riding costumes.Footnote ³³ But this synthesis of the weighty and the ephemeral, the philosopher and the tea table, can make the Spectator uncomfortable; thus Addison separates out the Saturday edition for papers of particular moral and religious seriousness. In contrast, Hume's philosophical project consists in precisely this mingling of the sociable and the philosophical. In “Of the Delicacy of Taste and Passion,” which inaugurates the 1741 volume, Hume puts his reader on notice that the beauties of rhetoric and weighty philosophical issues are fundamentally akin: the man of “Delicacy of Sentiment,” Hume claims, “receives more enjoyment from a Poem or a Piece of Reasoning than the most expensive Luxury can afford.”Footnote ³⁴

III. THE FOUR PHILOSOPHERS: THE ESSAYS AS DIALOGUE

The Four Philosophers essays follow in the tracks of both Cicero (whose De Finibus, which successively considers the doctrines of Epicureans, Stoics, and Sceptics, is a clear precedent) and the Spectator, but they do so in order to circle back, ultimately, to the Treatise.Footnote ³⁵ To show how Hume accomplishes this end, it is worth beginning with the straightforward observation that the Four Philosophers essays are to be read as a cohesive whole. The advertisement to Hume's first volume of essays includes the disclaimer that “the Reader must not look for any Connexion among these Essays, but must consider each of them as a work apart,” and although several of the essays canvas related material or examine an issue from multiple perspectives (such as the political series that constitutes essays 8–11 of Volume 1) it is broadly true that before the Four Philosophers each essay stands on its own.Footnote ³⁶ The parallel titles of essays 6–9 of Volume 2, however, signal to the reader examining the table of contents that they are to be considered together, and this impression is reinforced by the way in which each essay either anticipates or responds to the arguments of the others. The Epicurean's dismissal of “the severe Philosophers” who “have undertaken, the producing of an artificial Happiness” is an obvious salvo against the Stoic's valorization of “utmost Art and Industry” in his opening lines, just as the Platonist's low opinion of “the ignorant Applauses of Men” devalues the Stoic's aspirations to “an immortal Fame among all the Sons of Men.”Footnote ³⁷ Without ceasing to write within the essay genre, in other words, Hume has made his essays speak directly to each other and thus entered into a philosophical dialogue. The Spectator integrated Ciceronian content into the short prose essay; Hume now adds Ciceronian form.Footnote ³⁸

Indeed, the skillful and gradual transition from the genre of essay to the genre of dialogue is an important part of the effect of the first essay, “The Epicurean.” Before this essay inaugurates the Four Philosophers series, all of Hume's essays are written in a stable essayistic persona, speaking in a single first-person voice.Footnote ³⁹ “The Epicurean” inaugurates an unannounced shift into a series of dramatic voices, by means of which the viewpoint of the single narrator is replaced by a succession of four characters who talk both to the reader and to each other. Particularly in the first edition, Hume deliberately avoids signposting this shift in voice, so that the reader only gradually discovers that he or she (Hume consciously addresses his essays to both male and female readers) is no longer hearing the dicta of a single speaker.Footnote ⁴⁰ “The Epicurean” opens with a statement whose balanced and general style follows Hume's practice in the volume thus far and anticipates Samuel Johnson's Rambler of a decade later: “It is a great mortification to the vanity of man, that his utmost art and industry can never equal the meanest of nature's productions, either for beauty or value.”Footnote ⁴¹ The reader who has just completed Hume's previous essay, “Of the Rise and Progress of the Arts and Sciences,” perceives this sentence almost as a direct continuation of the statement with which that essay ended:

Upon careful rereading, these two sentences are totally different in content: the essayist in “Of the Rise” is arguing that a single genius such as Homer or Virgil can discourage potential followers and thus lead to the decline of the arts, while the Epicurean is arguing that human works will always be inferior to those of nature. On first reading, however, the shared register and vocabulary (“arts,” “sciences,” “soil,” and “produce” in “Of the Rise” anticipate “art,” “industry,” “nature,” and “productions” in “The Epicurean”) make the two sentences appear to be part of a single argument. It is only on the third page of the essay, with the second-person “You pretend to make me happy by reason”, that the reader becomes fully aware that he or she is reading not a spectatorial treatment of Epicureanism in general but rather a dramatic monologue from an exponent of that philosophy. Over the course of the “The Epicurean,” tone and style continue to transform, drawing the reader further away from the essay genre into that of the dialogue, culminating in a form that is almost dramatic. The first person singular, which appears only once in the first two paragraphs, occurs nine times in the second two. At the top of the fifth page of the essay, an allegorical procession of personified Pleasure and a train of Cupids approaches the speaker; a dinner banquet follows. Finally, with the dramatic character of the text fully established by the interpolated protests of the speaker's dinner companions as he withdraws into the woods (“But whither do you go? Or what new pleasures call you from our society?”), the essay ends with the speaker crooning into the ear of his lover Caelia, who almost blurs into the reader: “But while youth and passion, my fair one, prompt our eager desires, we must find gayer subjects of discourse, to intermix with these amorous caresses.”Footnote ⁴³ The reader begins reading the essay with the voice of Mr. Spectator in his or her ear, and ends it hearing a serenade from Robert Herrick.

Hume biographer Roderick Graham considers “The Epicurean” to be an amateurish, melodramatic performance; Timothy Engström argues that it is written “with such hyperbole that the effect is ironic and emptying of the position's command over the reader.”Footnote ⁴⁴ The latter is not exactly wrong, but seeing the essay as spinning out of rhetorical control or viewing it as nothing more than a joke at the Epicurean narrator's expense equally miss the point that Hume is making about philosophical reasoning. As noted above, Hume insists again and again in the Treatise on the crucial importance of “vividness” in forming our beliefs, and describes how practices like pilgrimages, Roman Catholic ritual or dogmatic (religious) education create belief by substituting pageantry and repetition for reasoned argument.Footnote ⁴⁵ Like Stanley Fish's Milton seducing the reader into a sense of his or her own sinfulness through his attractive depiction of Satan in Paradise Lost, Hume concludes “The Epicurean” with Caelia's willing seduction because the essay itself is a seduction, at the level both of genre—the reader is drawn into a dialogue without receiving any signal that he or she is departing from the temperate monologic voice of the essays thus far—and of argument, as the narrator's raptures represent an attempt to overwhelm the reader with “vivacity” or “liveliness” rather than a more closely reasoned argument.Footnote ⁴⁶

The previous essay, “Of the Rise and Progress of the Arts and Sciences,” offers a complementary insight into Hume's purpose. The argument of the Epicurean, for Hume, does not resemble the dogmas and rituals described as cementing belief in the Treatise merely by virtue of its appeal to vividness, but also in its reliance on authority and tradition rather than individual reasoning. Hume dismisses the ancient philosophical schools in “Of the Rise”: “Consider the Blind Submission of the ancient Philosophers to the several Masters in each School . . . Upon the Revival of Learning, those Sects of Stoics and Epicureans, Platonists and Pythagoricians, cou'd never regain any Credit or Authority.”Footnote ⁴⁷ Though none of the philosopher–narrators cite authorities of their respective schools directly, Hume has planted the idea in the attentive reader's mind that their pronouncements are not to taken as based purely on reason.Footnote ⁴⁸

Obviously, the surprise trick that makes “The Epicurean” effective cannot be repeated in “The Stoic,” but the second essay in the series has its own set of rhetorical techniques. The opening paragraph matches the neutral, learned tone of the first paragraph of the previous essay, reversing the hierarchical status of the words “art” and “nature” to refute the Epicurean's metaphor of life as a spontaneous product of nature and replace it with the metaphor of life as a painstakingly crafted artifact. Hume continues this negation by paralleling the first-person effusions of the Epicurean with a long series of second-person Stoic exhortations, with repeated imperatives and uses of “thou” and “thy”: “let [Nature] conduct the Machine, which she has so wisely fram'd” is rebutted by “Hearken to [Nature's] Voice, which so plainly tells thee, that thou thyself shou'd'st also be the Object of thy Industry.”Footnote ⁴⁹ The Epicurean thus imagines that the good life is like nature and the Stoic imagines that it is like art, while the Platonist, whose somewhat perfunctory essay comes third, constructs an analogy according to which the relationship between human art and the human mind suggests a similar relationship between nature and the divine mind, which should be our true object of contemplation and veneration.

Hume recycles the terms “art” and “nature” through the first three essays, building ever more complex analogical systems with them, in order to set the first three philosophers up for the deflating insight of the Sceptic, who is allowed the last (and longest) word: “When a Philosopher has once laid hold of a favorite Principle, which perhaps accounts for many natural Effects, he extends the same Principle over the whole Creation, and reduces to it every Phenomenon, tho' by the most violent and absurd Reasoning.”Footnote ⁵⁰ The reader's initial impression is that the Sceptic is Hume's avatar, and the first three philosophers are negative examples, the Humean equivalent of Socratic fall guys like Hippias or the Thomist pseudo-objections (“Surely God can't be both three and one!”) that the Angelic Doctor demolishes so efficiently in the Summa Theologica.Footnote ⁵¹

Certainly the Sceptic propounds the set of views closest to those of Hume as expressed elsewhere in the Essays and in the Treatise; it is also worth noting that the other three philosophers are given a footnote which identifies their ruling passion (so that the Stoic is, for example, “The Man of Action and Virtue”), while the Sceptic is not so described. But an account of the four essays which sees the Epicurean, Stoic, and Platonist as wrong-headed projectors corrected by the Sceptic ignores the way in which Hume's first three philosophers make arguments that in other places, particularly in the Treatise, come out of his own mouth in propria persona. The most obvious example of this is the Stoic's use of hunting as a metaphor for life on page 120 of Volume 2, employed after he has warmed to the topic of labor and standing in rough parallel to the Epicurean dinner party of pages 107 ff. of Volume 2:

This description closely follows Hume's use of the same metaphor in “Of curiosity, or the love of truth,” the final section of Book II of the Treatise: “there cannot be two passions more nearly resembling each other, than those of hunting and philosophy . . . the pleasure of hunting consists in the action of mind and body; the motion, the attention, the difficulty, and the uncertainty.”Footnote ⁵² Likewise the Epicurean identifies pleasure with virtue (“Pleasure smiles at my Languor. She beckons to her sister, Virtue, to come to her Assistance.”) in a way that is less theoretically sophisticated than, but perfectly consistent with, Hume's argument in the Treatise that “the distinction of vice and virtue arises from the four principles of the advantage and of the pleasure of the person himself, and of others”.Footnote ⁵³ Even the Platonist, whose views in general are scarcely accorded the dignity of refutation by the Sceptic, repeats, in his claim that applause for human works is really directed towards the mind from which they originated, the argument of the Treatise that “when we praise any actions, we regard only the motives that produced them, and consider the actions as signs or indications of certain principles in the mind and temper.”Footnote ⁵⁴ Conversely, the Sceptic's epistemology, according to which knowledge is the conformity of our mental conceptions to reality (“I endeavour only, by my Enquiries, to know the real Situations of the Planets; that is . . . to give them, in my Mind or Conception, the same Relations, that they bear towards each other in the Heavens”) is utterly at odds with the epistemology of Treatise 1.4.4 (Volume 1, page 152), which argues that if we accept, as the Sceptic does, that certain properties of external objects exist in our minds alone, we must doubt the existence of an external world entirely.Footnote ⁵⁵

The Sceptic's final, extended meditation on the limitations of philosophy (particularly its powerlessness in the face of human suffering) is important to the effect of the four essays as a whole, but not because it refutes or cancels out the statements that have gone before. Indeed, by not affixing a pair of descriptive epithets to the term “Sceptic” as he had done for the previous three philosophers, and otherwise leading the reader to expect that the Sceptic will demolish his colleagues' arguments, Hume is able to re-create the effect of ironically eluding the reader's expectation that was so successful with “The Epicurean”. The reader, if he or she is aware of Hume's authorship of the Treatise and thus of his skeptical sympathies, or perhaps has noticed that the author excepts “Sceptics” from censure in “Of the Rise and Progress of the Arts and Sciences,” expects the final essay in the series of four to have the last word, and finds the Sceptic's tolerant insistence on the variety of human temperament a salutary corrective to the unbalanced and intolerant views of the first three philosophers. But the very length of the fourth essay (almost exactly as long as the other three essays combined) makes the reader aware that the Sceptic, who expatiates on epistemological and scientific issues in which the other three philosophers take no interest, is himself an imperfect observer with a limited viewpoint, drawn by his own “predominant Inclination.”Footnote ⁵⁶ Furthermore, by the end of the essay, the Sceptic has offered two positive forms of philosophical reasoning which he considers legitimate, albeit imperfect, and they turn out to be restatements of the Epicurean and the Stoic positions: he acknowledges the power of reflections on the “shortness and uncertainty of Life” to lure us into “the flowery Fields of Indolence and Pleasure,” a clear acknowledgement of the Epicurean argument; and he argues for the influence of “a comparison of our own Condition with the Conditions of others,” something not unlike the Stoic valorization of “Glory,” which is the “portion of virtue.”Footnote ⁵⁷ Instead of refuting the essays that have gone before, the Sceptic has pointed out the flaws in their arguments and then adopted those very arguments anyway. The Sceptic has attempted to deconstruct his more earnest and positive colleagues, but the reader can see that they have returned the favor. Even his opening statement that the “infirmity of philosophers” lies in their intolerant belief that their “Pursuits are always . . . the most engaging: the Objects of [their] Passion, the most valuable: And the Road, which [they] pursue, the only one that leads to Happiness,” is repeated from the Platonist, who remarks that “In vain, by pompous Phrase and passionate Expression, each recommends his own Pursuit, and invites the credulous Hearers to an imitation of his Life and Manners.”Footnote ⁵⁸ The Platonist takes this observation and promptly turns to his own hobbyhorse, veneration of the divine; the reader must ask whether the Sceptic does the same.Footnote ⁵⁹

The Sceptic insists that a philosopher's worldview is a construct, that what Pope called the “ruling passion” predetermines the outcome of philosophical inquiry, but he cannot prove that this invalidates philosophical conclusions. Passions, in the end, trump reason, and abstractions like “glory” or “virtue” are in the end pragmatic compromises with the world around us: at the end of “The Sceptic” the reader reaches the conclusion, in other words, that Hume attempted so valiantly to present through the lengthy and complex reasoning of the Treatise.

The genre of the philosophical dialogue, on which Hume draws so skillfully in this set of essays, contributes to this effect. An obvious effect of arguments in dialogic form is to draw attention, as Hume wishes to do, to the importance of rhetorical technique in the presentation of philosophical assertions. Adam Potkay has argued that the model of ancient political eloquence provides the underlying metaphor for Hume's model of perception generally:

Potkay discusses at length Hume's politically oriented “Of Eloquence,” but does not comment on the Four Philosophers, which first appear in the same 1742 volume. I would argue that philosophical dialogue, in addition to the political oratory which Potkay emphasizes, provides a metaphorical ground for Hume's epistemology: our senses are, figuratively speaking, as likely to be persuaded by the blandishments of the Epicurean as by the foot-stamping of Demosthenes.Footnote ⁶¹

The genre of dialogue had strong philosophical associations for educated eighteenth-century readers. As Michael B. Prince has documented, the philosophical dialogue was a popular and prestigious genre in the eighteenth century, with a well-known ancient heritage and contemporary practitioners that included not only Shaftesbury but also Berkeley, Mandeville, and others.Footnote ⁶² In his discussion of Hume's Dialogues Concerning Natural Religion (written around 1750, within a decade of the Four Philosophers essays, but published only posthumously), Prince describes the genre's appeal as a vehicle for religious discourse because “it was thought to replicate in formal terms the conceptual movement of rational Christianity . . . [A]s within a providentially ordered nature, an initial appearance of randomness, multiplicity, and indeterminacy would give way to a final point of unity and order.”Footnote ⁶³ In Prince's view, the Hume of the Dialogues brings about the end of the philosophical dialogue as Berkeley and Shaftesbury had practiced it; Hume's trio of Philo, Cleanthes, and Demea offer no final resolution, of course, and Hume subverts the expected isomorphism between form and content for his own skeptical ends.

Prince's argument is rooted primarily in Philo's (and, he argues, Hume's) critique in the Dialogues of induction of the kind required to make deistic arguments from design work. This is one function of the form of dialogue; Hume's Sceptic opens his essay with a very similar critique of his interlocutors. But the hybrid features of dialogue and essay at work in the Four Philosophers also point to a different philosophical value—vivacity—which crucially informs, I have argued, Hume's thought over his entire career. In the Dialogues Philo is at great pains to set the limits of analogical and inductive reasoning. Our experience does not supply a firm basis for inferences about the nature of God: “Does not the great disproportion bar all comparison and influence?”Footnote ⁶⁴ But it leads Philo to more modest claims, for instance that “the cause or causes of order in the universe probably bear some remote analogy to human intelligence.”Footnote ⁶⁵ Hume's dialogic writings ask their readers to accept nothing more than a modest analogy between character and reader—both are hearing the text speak, both are open to entering the dialogue. By replacing the authoritative voice of discursive philosophy with multiple viewpoints, the dialogue enacts within the text the process of convincing and being convinced, of rhetoric shaping a speaker's argument and acting on a listener, and asks the reader to apply it analogically to him- or herself.

Hume is following his classical precedents here. Texts like Cicero's Tusculan Disputations use the dialogue as a way of introducing the student of philosophy to multiple approaches and lines of argument while still directing the reader or listener towards the author's set of beliefs—in the case of Cicero, Academic Scepticism. Dialogue in this case serves as something like a textbook in the history and practice of philosophy, a way of demonstrating how it is done.Footnote ⁶⁶

Hume cultivated dialogue in his own life. Although he made a point of never replying in print to pamphlets published against him, Hume was eager for philosophical conversation and correspondence, which he saw as a way of furthering the advancement of learning.Footnote ⁶⁷ Despite his frequently expressed mistrust of philosophical “schools” and “systems,” a 1753 letter to an adversary who had attempted to refute his Enquiry Concerning the Principles of Morals shows Hume himself willing to imagine that he is a member of one ancient philosophical sect among many:

In this connection, we might recall Hume's vocational anxiety in the era of the Treatise and the Essays, his need to find a “footing” and a “settlement” in the world.Footnote ⁶⁹ As this letter from a decade later shows, becoming a philosopher entails entering into a dialogue, finding a place within the larger conversation and attempting to make one's own speeches heard.

IV. CONCLUSION: ESSAY, DIALOGUE, SENTIMENT

The Four Philosophers essays use dialogical effects to underline the subjectivity and contingency of philosophical reasoning. Dialogue allows Hume to align his speakers with their respective philosophies on the basis of their temperaments rather than the content of their propositions; he makes it clear that his speakers are not Stoics or Epicureans because of a set of views they hold, although they do hold strong and distinctive views, but rather because of the sort of men they are (men of “Elegance and Pleasure,” or “Action and Virtue.”)Footnote ⁷⁰ Hume thus anticipates Herder's aphorism that “jeder vernünftelt doch nur nach seiner Empfindung” and enacts his similar statement in Book I of the Treatise that “all probable reasoning is nothing but a species of sensation. 'Tis not solely in poetry and music, we must follow our taste and sentiment, but likewise in philosophy.”Footnote ⁷¹

I have argued above that “sentiment” is a crucial term in Hume's epistemology of vivacity because it occupies a middle place in the polarity of “understanding” and “passion” which Hume establishes in the Treatise. The term “sentiment,” which all four of Hume's Philosophers use in their respective essays, is also highly relevant to Hume's mobilization of dialogic form to further his philosophical program. This is because “sentiment” forms a semantic bridge not only between the otherwise opposed concepts of “judgment” and “emotion” within the epistemological system of the individual, but also between the individual's relations to ideas and to other people. In the mid-eighteenth century, as now, a “sentiment” can be directed towards either a thought or a person. We might say, in the terms of the Four Philosophers, that the Stoic has sentiments about virtue, while the Epicurean has sentiments for Caelia. The multiple meanings of sentiment thus allow it to be both a form of common currency for philosophers (Cicero the Academic and Brutus the Stoic could both talk about sentiment, if they spoke English, because it is relevant to both their systems) and also a condition allowing exchange to happen (their affable sentiments for each other would keep the conversation going). If dialogue shows us that philosophy is cognate with rhetoric, it does so by reminding us that both operate on our sentiments.

In a sense, all of the Four Philosophers essays are about how dialogue happens, but the most self-conscious and sophisticated analysis comes from the Sceptic, in a paragraph that concludes that the best dialogues are the ones that acknowledge difference yet seek common ground:

Not coincidentally, this passage has the most concentrated distribution of the word “sentiment” in all of the Four Philosophers essays: it occurs five times in the single paragraph from which I have quoted, in several subtly different registers, and once more in the first line of the paragraph that follows.

A reexamination of the Treatise in light of the Four Philosophers essays reveals that dialogic tension has been part of Hume's project from the start—although in its earlier form, Hume's dialogues are with, and within, himself. The famous and much-analyzed conclusion of Book I, “Of the Understanding,” combines skeptical arguments against personal identity with confessions on the part of the narrator that his philosophical conclusions alter as his temperament varies, with the final result that he enters into a dialogue with his earlier writing self, whose sentiments were different:

The warmly written final pages of Book I in particular show the narrator questioning himself repeatedly, as he comes to terms with his own personal instability, and the way in which both his beliefs and his attitudes towards philosophy itself vacillate wildly depending on his environment and mood: “But what have I here said, that reflections very refin'd and metaphysical have little or no influence upon us? This opinion I can scarce forbear retracting, and condemning from my present feeling and experience.”Footnote ⁷⁴ Hume knew well the changeability and instability of his own mind, as his 1734 letter to a physician indicates.Footnote ⁷⁵

In addition to the debate between selves at different points in time (such a debate itself standing in debate with Hume's apparent skepticism in places about the identity of the self), the Treatise also dramatizes synchronic conflict between the faculties of the mind itself, as common sense and philosophical reason grapple for belief:

Similarly, “Of the Passions” depicts different emotions mixing with each other, creating varied effects in varied proportions.Footnote ⁷⁷ The necessity of conversing with one's own earlier self, and even within oneself, in addition to conversing with others, makes dialogue a natural vehicle for philosophical inquiry.

To summarize: Hume, writing in the early 1740s, feels that the Treatise has failed to convey his views to contemporary readers. In addition to the typical ambition of a young author, Hume is eager to make his ideas widely known because his philosophy suggests to him that ideas that no one understands are for that reason not true—that “vividness” and “convincingness” are as crucial to epistemology as they are to rhetoric—both of which, of course, appeal ultimately to “sentiment.” Finding a place in the world as a successful philosopher, for Hume, thus entails becoming a convincing one. Instead of creating a persona called “The Philosopher” or the like to expound the views of the Treatise again, he turns to a hybrid form, combining elements of the genres of Addisonian essay and Ciceronian philosophical dialogue, to enact rather than merely state the work's main epistemological and ethical arguments. By leaving the dialogic nature of the series implicit, disguised (at least initially) under the discursive structure of an essay, Hume surprises the reader into being “seduced” by different chains of analogical reasoning that blend philosophical argument with dramatic and rhetorical appeal; first the Epicurean, then the Stoic, illustrate the argument that “When I am convinc'd of any principle, 'tis only an idea, which strikes more strongly upon me” more suggestively than Book I of the Treatise could.Footnote ⁷⁸ Stretching the claims of analogy to their breaking point with the metaphysics of the Platonist, Hume releases the tension with the Sceptic's explanation that each philosopher's “predominant inclination” imprisons him within a single set of values and beliefs, using the first three philosophers, in other words, as model cases for the argument denying human freedom which falls at the end of Book II of the Treatise. Over the course of the final long essay the reader realizes that the Sceptic, whose ideas are generally closest to Hume's, is just as bound by his own prejudices as his predecessors, and comes to recognize that philosophical consolations, though they are susceptible of doubt in an absolute sense, are still necessary, much the same conclusion that Hume's narrator arrives at in the final pages of Book I of the Treatise.

By showing rather than telling, and drawing on his readers' generic expectations and his own facility for dramatic irony, Hume is able to present, in a simplified yet subtle form, three central and controversial claims—the centrality of vivacity as epistemological criterion, the ascendancy of causality over the free human will, and the inability of the human mind ever to cease from philosophizing—from his three-volume magnum opus, but in seventy-three octavo pages and with enough room for both a pastoral love scene and Thucydides' account of Athenian jollity during the plague. The Sceptic, in the end, closes with a wry and fully Humean statement that the pleasure of philosophy lies not in the prospect of reaching certain and irrefutable conclusions, a lost cause, but rather in the pursuit, that is to say the dialogue, itself: