The Infidel and the Professor: The Friendship of Adam Smith and David Hume

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Dennis C. Rasmussen for AdamSmithWorks

September 1, 2018
The Infidel and the Professor: David Hume, Adam Smith, and the Friendship That Shaped Modern Thought (Princeton University Press, 2017)
The Infidel and the Professor is the first book to center on Adam Smith’s friendship with David Hume, which is arguably the greatest friendship in the history of philosophy. The book follows the course of their friendship from their first meeting in 1749 until Hume’s death more than a quarter of a century later, examining both their personal interactions and the impact that each had on the other’s outlook. 
My primary aim in writing the book was to tell the story of Hume and Smith’s friendship in an accessible and entertaining way in hopes of reaching as broad an audience as possible. But I also sought to make a number of contributions to the scholarly literature on these thinkers. Some of these contributions are outlined in what follows, starting with a few broad points and then moving to some more specific ones.

The Infidel and the Professor
First, and most obviously, the book draws on all of the available evidence to provide the fullest account yet of Hume and Smith’s personal and intellectual relationship. My primary source, naturally, is the full range of Hume’s and Smith’s works. As I seek to demonstrate, there are numerous references to Hume, both explicit and implicit, throughout virtually everything Smith wrote. The reverse is less true, as Hume—the older of the two by a dozen years—had composed almost all of his writings before Smith began to publish his (though Hume did write an anonymous review of The Theory of Moral Sentiments soon after its release). 
I also analyze their correspondence—there are fifty-six surviving letters between them—and draw on a host of other contemporaneous and near-contemporaneous sources, including Dugald Stewart’s biography of Smith; the myriad writings of James Boswell; and the autobiography of the Moderate minister Alexander Carlyle and the journal of the playwright John Home, both of whom traveled in the same circles as Hume and Smith. I also make use of the private correspondence of a number of their acquaintances; the periodicals, book reviews, and obituaries of the day; and the anecdotes collected by Henry Mackenzie and John Ramsay of Ochtertyre, among others.
In this same vein, the book offers the first systematic treatment of Smith’s responses to Hume’s thought over the course of his career, from his early essay on the history of astronomy (written by 1746) through the final revisions of The Theory of Moral Sentiments (1790). While the influence of Hume is apparent in almost all of Smith’s works, Smith did not simply adopt his friend’s views wholesale. On the contrary, he modified almost everything he touched. There have been a number of journal articles and book chapters examining Hume’s influence on Smith with respect to a particular question or theme—Hume and Smith on sympathy, for instance, or Hume and Smith on justice—but none examine their intellectual relationship in anything like a comprehensive manner. 
Throughout the book I discuss Smith’s responses to Hume on a wide variety of topics: epistemology and religion in the astronomy essay (chapter 2); economics and politics in Smith’s jurisprudence lectures (chapter 3); sympathy, utility, justice, and religion in The Theory of Moral Sentiments (chapter 5); politics, the advantages and drawbacks of commercial society, the benefits of free trade, the question of church establishment, and the American conflict in An Inquiry into the Nature and Causes of the Wealth of Nations (chapter 9); and religion and virtue in the final revisions of The Theory of Moral Sentiments (epilogue).
Smith’s religious views have been the subject of much scholarly debate, and I contend that they were substantially closer to Hume’s—that is, substantially more skeptical—than is usually assumed. This is not to say, of course, that Smith was an atheist. On the contrary, it seems likely that he believed in a distant, perhaps benevolent, higher power. But he was almost certainly not a believing Christian, and he was suspicious of most forms of religious devotion. I therefore describe him as a “skeptical deist” (as opposed to an outright skeptic like Hume). Here too I draw on the full range of Smith’s corpus, from his astronomy essay through the final edition of The Theory of Moral Sentiments, as well as his correspondence, in making my case. 
One of the running themes of the book is the divergence between Hume and Smith in terms of the public postures that they adopted with regard to religion: whereas Hume was fairly forthright about his lack of faith, Smith generally went to great lengths, in both his writings and his personal life, to avoid revealing much about his religious beliefs (or lack thereof). Contemporaries frequently noted that Smith was “very guarded in conversation” when the topic of religion came up, and the little that he wrote on the topic is sufficiently ambiguous to leave many readers unsure of his ultimate convictions. These contrary postures led to equally contrary reputations: Hume was christened “the Great Infidel” and was deemed unfit to teach the young—he twice sought professorships, but in both cases the clergy opposed his candidacy decisively—while Smith became a respected professor of moral philosophy. (Hence the contrast implicit in the title, The Infidel and the Professor.)

Credit where it’s due
For much of the twentieth century Smith’s moral philosophy was seen as little more than a series of footnotes to Hume’s, but I argue that his version of moral sentimentalism in fact incorporates several significant improvements on his friend’s. Virtually the whole of The Theory of Moral Sentiments shows unmistakable signs of Hume’s influence, down to the very examples that Smith uses, and the similarities between their moral theories are broad and deep: both view morality as an eminently practical and human phenomenon, rather than one based on any kind of sacred, mysterious, or otherworldly authority; both hold that morality derives from human sentiments rather than reason; and both posit that right and wrong are established by the sentiments that we feel when we adopt the proper perspective, one that corrects for personal biases and misinformation—Hume’s “common point of view” and Smith’s “impartial spectator.” 
Yet, as I show in chapter 5, Smith deviated from Hume’s moral theory on four major topics: the nature of sympathy (which Smith argues almost always involves a kind of imaginative projection into the situation of another person, rather than the straightforward emotional “contagion” that Hume posits), the role of utility (which Smith argues plays a smaller role in moral judgment than Hume claims), the foundation of justice (which Smith argues springs not from reflection on its usefulness, as Hume contends, but rather from the sentiment of resentment), and the effects of religion (which Smith maintains has more practical benefits than Hume allows). In all of these cases Smith’s views are more nuanced, and arguably more sophisticated and persuasive, than Hume’s.
On the other hand, I also argue that, just as Smith’s contributions to moral philosophy have been unduly neglected in favor of Hume’s, Hume’s contributions to political economy have been unduly neglected in favor of Smith’s. As an economist, Hume has long been regarded as a minor predecessor of Smith, insofar as he is taken notice of at all, but in fact he argued for free trade and stressed the moral, social, and political benefits of commerce several decades before Wealth of Nations appeared. 
Hume’s essay “Of Luxury” (later retitled “Of Refinement in the Arts”) is one of the most forceful, comprehensive, yet succinct defenses of the modern, liberal, commercial order ever written. As I argue in chapter 9, it is striking how many of the central arguments of Wealth of Nations build on Hume’s insights. Here too, though, Smith diverged from Hume’s views in important respects, above all in his greater readiness to acknowledge potential drawbacks of commercial society. Smith accepts that commercial society necessarily produces massive inequalities; that an extensive division of labor can exact an immense cost in human dignity by rendering people feeble and ignorant; that wealthy merchants and manufacturers will often collude against the public interest; and that the desire for wealth often leads people to submit to endless toil and anxiety in the pursuit of frivolous material goods that provide only fleeting satisfaction. 
This is not to say that Smith’s embrace of commercial society was in any way partial or halfhearted. On the contrary, he joined Hume in regarding commercial society as unequivocally preferable to the alternatives. Yet even as Smith agreed with Hume that the benefits of commercial society—liberty, security, prosperity, and the rest—vastly outweigh the costs, he was far more willing to acknowledge that there are costs involved, and to seek ways to ameliorate them.

Friendship, even in death
Smith resolutely refused to posthumously publish Hume’s Dialogues Concerning Natural Religion, despite Hume’s request that he do so, and his behavior in this instance is almost universally regarded as unnecessarily cautious, utterly inexplicable, or even an act of betrayal—a denial of his best friend’s dying wish. I argue in chapter 10, however, that this episode was far less acrimonious and philosophically charged than is generally assumed. A number of scholars have claimed that Smith refused to publish the Dialogues because he was disturbed or even scandalized by the contents of the work, but if Smith’s religious views were as close to Hume’s as I suggest throughout the book then this explanation seems unlikely. 
The likeliest explanation, in my view, is also the simplest: as Smith himself indicated in a draft letter to their mutual publisher, William Strahan, he was wary of the public “clamor” that the book would provoke and the effects that this clamor would have on his own “quiet” and Hume’s posthumous reputation. Was this, then, an instance of excessive caution, or even cowardice? If it was, then it was a failing that was not unique to Smith: every one of Hume’s friends who knew about the Dialogues urged him not to publish it. 
If the unanimous counsel of Hume’s friends is not enough to exonerate Smith, then Hume’s own words and actions should be. After all, Hume himself had refrained from publishing the work for two and a half decades, for the very same reason that Smith refused to do so: because (as he explained to Strahan) it would create a “clamor” that would prevent him from living “quietly.” Even the wording of their explanations is nearly identical. The more perplexing question is not why Smith refused to publish the Dialogues but rather why Hume was suddenly so adamant about publication after holding the work back for twenty-five years, and even more why he sought to foist this obligation on Smith. Hume may have reckoned that he had little left to lose at that point, with one foot almost in the grave, but obviously Smith was not in the same position. Moreover, Hume knew full well that Smith was always anxious to preserve his privacy and tranquility—his “quiet.” All things considered, then, I suggest that Hume’s part in this exchange is more difficult to account for than Smith’s.
Finally, I provide the fullest account yet of the abuse that Smith suffered as a result of his Letter from Adam Smith, LL.D. to William Strahan, Esq. (1777)—the only work other than his two books that he published under his own name during his lifetime. The Letter to Strahan is an ostensible letter on Hume’s last days, death, and character that was published alongside Hume’s brief autobiography, My Own Life, and because of Hume’s reputation for impiety it proved immensely controversial. 
In his Letter, Smith chronicles—some would say flaunts—the cheerfulness and equanimity of Hume’s final days and describes his unbelieving friend as a paragon of wisdom and virtue, all of which generated outrage among the devout. Smith later commented that this work “brought upon me ten times more abuse than the very violent attack I had made upon the whole commercial system of Great Britain.” Virtually all Smith scholars are familiar with this line because of the colorful reference to Wealth of Nations, but far fewer know the precise nature and extent of the abuse that Smith faced as a consequence of his tribute to his friend. In chapter 12, I document the (often vicious) reactions to the Letter to Strahan by George Horne, Samuel Johnson, James Boswell, Edmund Burke, and many others, ranging from just after its publication to well into the nineteenth century.
In all, I hope that The Infidel and the Professor will provide a useful introduction to Hume and Smith for readers who are unfamiliar with these thinkers while at the same time contributing to the scholarly literature in all the ways described above.

P.S. Rasmussen subsequently recorded this #AMA (Ask Me Anything) in October of 2019 in response to readers' questions.