Cicero is back! I make that declaration for two reasons. First, Cicero’s political theory—long obscured by the dark shadow cast by the nineteenth-century historian Theodor Mommsen—has lately returned as a subject of serious scholarly study. A generation ago, a few lonely voices within our discipline sang Cicero’s intellectual praises. Now books on his political thought pour forth from academic presses, and articles on the topic regularly appear in top mainstream journals.

The second rationale for my proclamation stems from the extent to which scholars have begun to track the various facets of the Ciceronian reception in the subsequent history of Western political theory. Cicero was, of course, the only theorist of any consequence from classical (pre-Christian) antiquity whose writings were available without a break throughout the following centuries. In recent times, numerous scholars have turned their attention to elements of his legacy. One thinks of Dean Hammer, Dan Kapust and Gary Remer, among others, who have contributed to the revival of interest in how Cicero has been adopted and adapted by a plethora of successors. From Moral Theology to Moral Philosophy constitutes an especially substantial and admirable addition to this literature.

Any effort in a short review such as this to summarize with acuity the complexities of Tim Stuart-Buttle’s argument is surely doomed to failure: the scope and quality of scholarship on display are just that sophisticated. So instead let me offer a few take-away points that I found to be especially insightful and compelling. Stuart-Buttle’s big picture project, as I understand it, is to investigate the lineages and transformations of English moral and social philosophy over the course of the seventeenth and eighteenth centuries through the prism of Ciceronian thought. One might imagine that this had already been accomplished in the work of Knud Haakonssen and those who have taken a similar approach. For them the key figures were thinkers such as Hugo Grotius and Samuel Pufendorf, whose modifications of natural law doctrines purportedly set the stage for the emergence of the agenda pursued by David Hume. But Stuart-Buttle narrates a very different tale that opens with John Locke (of all people!). The story—as the book’s main title suggests—walks us through the stages that lead from the profoundly religious Lockean outlook to the Humean effort to establish a wholly and unabashedly secular foundation for all forms (moral, social, and political) of human interaction. On the surface, this may appear quite a leap indeed.

So, how does Stuart-Buttle accomplish such a feat? He foregrounds a key aspect of Cicero’s thought that has nevertheless received precious little attention: his oft-expressed commitment to the moderate skepticism of the New (or Third) Academy. A virtual article of faith holds Cicero to be a Stoic sage and an implacable foe of Epicureanism. Yet a direct encounter with Cicero’s writings yields the conclusion that his philosophical framework was characterized by a studied anti-dogmatism. In step with Carneades, the reputed founder of the Academy in its skeptical phase, Cicero consistently subscribed to the position that all knowledge claims are probabilistic and provisional, and thus always open to criticism and reevaluation. Some of Cicero’s acolytes across the ages—I would cite the twelfth-century philosopher John of Salisbury as but one instance—conscientiously embraced this dimension of their master’s teachings. As Stuart-Buttle demonstrates, scholars manifest a pronounced disinclination to consider the implications of Ciceronian modern skepticism for modern moral and social philosophy. They do so, however, at their own peril.

In considering Stuart-Buttle’s narrative, it may seem exceedingly strange to associate Locke, given the deeply Christian religious roots of his moral philosophy (unsystematic though it may have been), with any sort of skepticism. In general, despite the pleas of scholars such as Neal Wood, Raymond Polin, and John Marshall, the mainstream literature on Locke has in general concertedly resisted drawing connections between Locke and Cicero. Yet, by means of a careful and thorough historical and textual inquiry, Stuart-Buttle suggests a set of complementary grounds for positing just such an association between Cicero’s espousal of New Academic skepticism and Locke.

The first is epistemological. A major component of Locke’s philosophical agenda arose from his alignment with the growing scientific emphasis on the primacy of empirical knowledge, a theory with which his name has become synonymous. Although not dispositive, the fact that the epigraph of the Essay Concerning Human Understanding is drawn from Cicero’s De natura deorum is certainly suggestive. As Stuart-Buttle observes, Locke shared Cicero’s desire to dispense with “the absurdity of man wasting ink—and spilling blood—in defense of opinions and doctrines which were entirely incomprehensible” (p. 22). In related fashion, Locke found in Cicero a comrade in the fight against sectarianism, which “undermined the bonds which held communities together” and “precluded citizens from exercising their independent judgment on questions which ought to be of the greatest concern to them as members of political and religious societies” (p. 23). In other words, Ciceronian moderate skepticism warded off the tendency for group-think—whether informal or imposed—to restrict human autonomy and deny moral agency. Cicero’s thought also promoted acknowledgment of the limits of humanity’s rational capacities, setting constraints on assertions of moral certitude based on supposed privileged access to truths that only “right reason” could sustain. Locke did not, of course, deny that such moral truths exist, only that they ultimately pertain to revelation to which no person, without displaying a pronounced lack of humility (a Christian virtue), could claim with certainty. Finally, and perhaps most profoundly, Stuart-Buttle identifies as Ciceronian a tendency he finds in Locke to concern himself with the question of “why,” without great philosophical perspicuity, people live with one another for the most part according to moral and social norms. In other words, Locke supposedly follows Cicero in downplaying the overarching “ought” questions in favor of the observation that human beings do in fact engage with their fellows in a cooperative and harmonious, rather than rancorous, fashion. Stuart-Buttle ascribes this phenomenon to a fundamental human concern for “reputation,” which serves as a sort of self-correcting mechanism that keeps most people in line most of the time.

It is beside the point to ask whether—if Stuart-Buttle’s narrative holds water—Locke “got” Cicero accurately or not. To do that would be to invoke a purity test that demands too much of any scholar. Indeed, this is why I have misgivings about Stuart-Buttle’s occasional use of the word “influence” to frame his account. Too much of the story he tells belies the attempt to judge “who influenced whom and how.” The famed historian of political thought Francis Oakley once bemoaned the “anxieties of influence” (a phrase obviously derived from Harold Bloom) that he considered rampant among intellectual historians, primarily of the Cambridge School persuasion. But—and this is what Stuart-Buttle illustrates brilliantly—the real challenge is to uncover with precision how texts by an author such as Cicero were read and redefined along the way. A path from Locke to Hume that Stuart-Buttle charts would seem, on the face of it, highly implausible. From Moral Theology to Moral Philosophy demonstrates how that route may be navigated in a truly sensible and feasible fashion when one relies on Cicero as the guide.