This short, engaging but rather curious book rummages through the Natural History of the elder Pliny for examples of his economic observations and reasoning in order to see what they reveal about Roman attitudes to innovation and economic growth. A brief Introduction helpfully outlines the structure and argument of the book, which has three salient points. Since proxy data, Richard Saller argues, are not capable of replacing the lack of direct data to measure economic performance in the Roman world, we need to revisit the economic attitudes expressed in surviving authors. By performance, he means sustained growth due to continuing innovation, not a one-off boom due to increased trade resulting from the unification and pacification of Rome's empire, which is what he thinks the archaeological evidence does attest. He picks Pliny's Natural History because of its size and content — 400,000 words on 20,000 ‘worthwhile facts’ (35) — and avowed aim of ‘usefulness’ (utilitas), which he compares to eighteenth-century encyclopaedias.

S. discusses in ch. 2 the purpose and intended audience of Pliny's Natural History. Pliny's claim of ‘usefulness’ to farmers and artisans is, as other scholars have noted, a literary trope; his real aim was a comprehensive compilation — achieved through obsessive note-taking — to preserve past knowledge of the natural world for an educated elite audience. If indeed, adds S., they could find what they wanted in his thirty-seven volumes, noting in an excursus that Pliny records sixty remedies for rabies scattered over ten books. Ch. 3 observes, following Beagon, that while Pliny occasionally recognises that the discovery of and trade in new resources brought by Roman imperialism has ‘improved life’ (50), his overriding view is that nature is divine and is being abused through human greed, a Stoic idea with contemporary resonance (138). S.'s principal addition to study of the Natural History is his review in chs 4 and 5 of passages where Pliny mentions innovations and their impact or makes economic observations. Again, while Pliny occasionally laments the scarcity of Roman innovations, which he, like some modern scholars, attributes to the absence of competitor states (70–7), he only offers a hotchpotch of technical tips to do with agriculture and a few economic observations about commerce and markets, almost all derivative and banal. What Pliny prizes is knowledge; commerce and innovation he tends to associate with greed. In ch. 6, S. notes that Pliny was only cited as an authority in Late Antiquity to the Renaissance, and he outlines the difference, with an excursus on fulling, between Pliny's work and the ‘dictionaries … of Arts and Sciences’ of John Harris (1704–10) and Ephraim Chambers (1728) which explicitly aimed to promulgate new discoveries that could improve the human condition.

S. claims in his first chapter that proxy data, from shipwreck statistics to Greenland ice cores, remain inconclusive for assessing sustained growth, even if bundled into an Economic Complexity Index (see Kevin Ennis’ excursus on Morgantina at 25–31). The case, however, is patchy and superficial, and needs to be made properly elsewhere. It would have sufficed here to say that mentality still matters for assessing sustained growth, and for mentality we still need to read ancient authors. Disappointingly, however, S.'s Conclusion is an inconclusive as his proxy data: Pliny occasionally shows awareness of the value of innovation and laments its (supposed) absence at Rome, but overall shows no positive interest in it. So which was the real Pliny? Like other writings of the Neronian age about the natural world and its marvels, the Natural History, published under Titus but begun under Nero, was meant to be read to diners for entertainment, just as Pliny had had his sources read to him while dining (33). Pliny was not really different from Cicero nor more ‘practical’ (133–4); the Natural History records mainly Greek knowledge and is imbued with a hostility to profit (‘greed’) adopted from Greek tradition. No elite Roman, as far as we know, compiled useful knowledge about ‘Arts and Sciences’ like Harris and Chambers (not themselves of elite origin). There were, however, many Roman technical, commercial and financial innovations conducive to sustained growth (some noted dismissively at 78) which somehow did get disseminated. The Periplus Maris Erythraei (‘Voyage round the Red Sea’), for instance, is a rare survival of a practical treatise by a non-elite author, which happens to be contemporary with Pliny, whose own description (6.101) of the Red Sea route fails to mention the important new Roman-period port of Myos Hormos. It is unclear whether Pliny's apparent disinterest in Roman innovations was more literary than real; maybe reading and writing in the Greek literary tradition did make the Roman elite less disposed to take an interest in the innovations being made around them and to invest in their development and application.