The last two decades have witnessed an incredible flowering of studies on the Roman economy, one absolutely unmatched in any other area of Roman history, and one for which ample evidence may easily be found in the important Oxford Roman Economy Project (https://www.romaneconomy.ox.ac.uk/) organized by Alan Bowman and Andrew Wilson. Where once the powerful ideological (both ethnological and Marxist) frameworks of Karl Polanyi and Moses I. Finley, who denied the applicability of modern economic theory to the ancient economy, held sway, contemporary approaches are now often strongly indebted to the so-called new institutional economics (NIE). This sea change can be seen already and with clarity in The Cambridge Economic History of the Greco-Roman World (2007), coedited by Richard P. Saller, author of the book presently under review.

According to this model, the Roman economy produced sustained but limited economic growth over a very long period due to the presence of a salubrious mix of “institutions” such as firm property rights, low taxes, efficient government, good infrastructure, and, of course, the famed Roman imperial peace (Pax Romana) that marked the two centuries following the fall of the republic amid shattering civic strife. While other equally fashionable approaches point to external shocks like climate change and disease, the ultimate decline of the Roman economy, in NIE approaches, is mostly understood to have resulted from the growth of an increasingly unwieldly, institution-weakening, and excessive government apparatus. Saller's brisk and slender new book, Pliny's Roman Economy, aligns with the NIE model but—largely inspired by the work of Joel Mokyr on the creation of a “culture of growth” in Europe before the Industrial Revolution—focuses especially on the institutional contribution of culture.

In the absence of serial or aggregate statistics from contemporary sources, Roman economic historians have tried, at least since Keith Hopkins's groundbreaking 1980 article “Taxes and Trade in the Roman Empire” (Journal of Roman Studies), to measure economic performance by using (usually archaeological) proxies: for Hopkins, shipwrecks and the volume of circulating silver coins; for others more recently, things like livestock stature, the quality of extant pottery, and now strata of lead pollution in the Greenland ice cap. Saller has rejected the full evidentiary validity of such proxies, recently arguing (in “Lead Pollution and the Roman Economy,” Journal of Roman Archaeology [with D. Pavlyshyn and I. Johnstone; 2020]) that the lead pollution data, properly understood, actually show a 20 percent decrease in economic activity over the course of the Pax Romana, a finding presumably at odds with the historical picture. Without a fine-grained proxy as a magic bullet, Saller argues, historians looking for Roman growth should cast as wide a net as possible for sources describing economic behavior, complementing archaeological evidence with textual (even literary) evidence.

Here Saller singles out Pliny's Natural History, composed by the wealthy and tireless Roman knight (eques) and government official before his tragic death in the eruption of Mount Vesuvius in 79 CE. The Elder Pliny's sprawling work, the largest extant from imperial Rome, is vast in size and encyclopedic in scope, comprising thirty-seven books overflowing with, by his own count, some twenty thousand discrete “things worth knowing,” drawn from hundreds of authorities, in every practical field of knowledge from astronomy to zoology. Whether we would ourselves classify, for example, forty or so (erroneous and often toxic) cures for rabies as res dignae or not, Pliny's stated aim in writing was utilitas (profit or usefulness) for his stated audience of humble (and alas, largely illiterate) farmers and artisans.

Pliny's Roman Economy is often an enjoyable read, especially on the topic of inventions, but its argument is stuffily understated and equivocal when not plainly anachronistic. On the one hand, Saller casts the Natural History as the truest literary witness to innovation, investment, and the culture of growth in imperial Rome and as a worthy complement to the growing corpus of archaeological data. Yet, in Mokyr's terms, as Saller acknowledges, there was barely any “culture of growth” in Pliny at all. Putting aside the fact that it was too expensive and too vertiginously comprehensive to reach a practical audience before print and wider urban literacy, the Natural History reflects the world view of its author, with its Stoic attacks on luxury and moralizing paeans to barter and ancient virtue, and not at all the world view that anticipated “the Great Enrichment,” with its mechanical philosophy, its precise instruments and quantifications, its replicable experiments, its organs for arriving at scientific consensus, its rationalizing and reformist view of commerce and commercial society, and so on. A related question arises: What would Saller have found if, for example, he compared Pliny's encyclopedia not with Ephraim Chambers's Cyclopædia but with Isidore of Seville's Etymologies, penned in seventh-century Spain rather than eighteenth-century London? Would Isidore too be a witness to economic culture in the (much later) Roman world? Or had the growth mostly stopped and the culture remained mostly the same? Saller does not ask such questions.

On the other hand, Saller finds in Pliny a Roman imperial economy that promoted “Smithian growth” and discouraged “Schumpeterian growth” (p. 137). Saller, knowing the causes of growth according to Enlightenment and modern economists, roots them out like a truffle-hunting dog in the first-century forest. We might, adopting the recent schema of Peter Thiel and with no less anachronism, just as well suggest that Pliny's Roman economy promoted one-to-n growth but discouraged zero-to-one growth. For Saller, Pliny, who saw the Rome of his day as poor in discoveries compared with a Hellenistic and mythical past of more abundant inventa, is aware of the Schumpeterian link between competition and innovation (and growth), yet Pliny's language of innovation focuses chiefly not on human agency but on a mysterious and passive process of fortuitous discovery and divine beneficence. A richer or more creative book, one that went beyond the search for retroactive simulacra of deracinated modern economic doctrines in ancient books, might have formulated its problematique not in only one direction (modern to ancient) but in both directions; Saller seems uninterested in the fact—to pick just one—that innovating entrepreneurship was sometimes theorized in the twentieth century, within Schumpeter's own milieu, with the aid of explicitly classical concepts, like the entrepreneur as daimōn-inspired or as a Solon-style “founder.”

Perhaps Pliny's Natural History can be read as a sort of cultural-economic index of its day, analogous with Diderot's Encyclopédie for its own age, but let it then tell us what it knows rather than what we know. The shortcomings of Pliny's Roman Economy speak, ultimately, not to any defect in Saller's acknowledged mastery of the history of the Roman economy but to how difficult (and how dangerous) it is to do revisionist economic history in a modern key from ancient literary sources.