When one asks what event marks the fall of the Roman Republic, it is tempting to answer Caesar's crossing of the Rubicon – ‘a momentous deed’, in the words of E.S. Gruen – in 49 bce as inaugurating a chain of events after which ‘Republican institutions endured largely as archaisms’ (E.S. Gruen, The Last Generation of the Roman Republic [1974], p. 1). To be sure, Gruen does not suggest that 49 was the end of the Republic, nor does he think that the fall of the Republic brought about the civil war, but rather the opposite. Yet choosing 49 as the turning point is not the only way to go; we might point to the years 44, 43, 31 or 27 bce just as easily. ‘Our whole picture of what republican politics consisted of in Rome’, as H. Flower puts it, ‘depends on when and how we think it came to an end’ (H. Flower, Roman Republics [2010], p. 15). A further difficulty is the fact that, as M. emphasises towards the beginning of her fine new book, what we might call the Roman Republic – a regime centring on ‘the ideal of a self-governing citizen body’ – was not understood as a ‘res publica in these terms’ by the Romans themselves, and as such, ‘they also did not identify a moment at which this system ceased to exist’ (p. 12).

Rather than look to formal constitutional analysis to make sense of Roman political thinking, a move that would be at odds with ‘a discourse community that largely avoided systematizing its terminology, formalizing its constitution, or extrapolating abstract principles from norms and customs’ (p. 20), M. turns to a metaphor through which Roman writers – including Varro, Cicero, Sallust, Horace, Livy, Ovid, Velleius, Valerius Maximus, Manilius, Seneca (the Younger and the Elder) and Lucan – ‘responded to constitutional change’ (p. 22). That metaphor is, as the title indicates, the body politic.

M. begins with an introductory chapter in which she lays out her interpretative framework with respect to metaphor; she draws on H. Blumenberg and is particularly interested in changes in metaphorical language over time. M. also explains her usage of the terms ‘Roman Republic’ and ‘Roman Republicanism’ in the introduction (p. 3). Given that the Romans themselves did not have any single term ‘to specify that political system that evolved after the mythologized expulsion of the kings’ (p. 4), M. deploys the terms (featuring upper-case Rs) in a descriptive rather than normative sense, entailing ‘the questions, problems, and concepts that Roman themselves regarded as politically important’ (p. 20). Such a move is salutary – after all, writers such as Tacitus expressed ‘republican’ claims, and ‘republican’ writers, such as Cicero, could make arguments that lent themselves to autocracy.

Through five chapters M. develops her argument with care and precision. Chapter 1, ‘The Divided Body Politic’, centres on Menenius Agrippa's story of the body divided against itself in 494 bce, along with its afterlife in Cicero and Sallust; Chapter 2, ‘The Sick Body Politic’, turns to metaphors of illness and their relationship to vice in Varro and Cicero, with Cicero holding ‘the paradoxical idea that violence is both the disease from which Rome suffers and the cure for its ills’ (p. 85). ‘The Augustan Transformation’, Chapter 3, explores the increased emphasis on the head of state metaphor in Horace, Ovid and Livy. Given the wariness with which such a metaphor had been viewed, it was a crucial move in that ‘Only after it had been rehabilitated as a positive signifier of statesmanship … could [the head metaphor] be used in relation to contemporary affairs’ (p. 130). Chapter 4, ‘Julio-Claudian Consensus and Civil War’, features a series of writers for whom the quality of the princeps serves to differentiate a ruler like Caligula from a ruler like Claudius, who functioned as a healer of the body politic, a differentiation that in turn ‘reflected the growing entrenchment of autocracy in the Roman political imagination’ (p. 162). ‘Addressing Autocracy under Nero’, the fifth and final substantive chapter, shows Seneca assimilating the body politic to Nero himself, enabling him to argue that the ‘mercy that he shows to others is therefore also that which he shows to himself’ (p. 173), while Lucan subverts the pro-autocracy dimensions of medical metaphors to deploy them ‘in opposition to rather than in service of autocracy’ (p. 186).

M.'s book is an outstanding work of intellectual history and classical scholarship, but it is in its normative implications that I, as a political theorist, found it to be even more impressive. I note, first, M.'s concluding engagement with Florus, for whom the ‘duality of mind and body’ is part and parcel of his ‘prioritization of peace over liberty’ (p. 203), a priority that is evident in his portrayal of the emergence of sole rule as necessary to prevent civil war. Not only, though, is it the case ‘that the implementation of sole rule did not solve the problem of civil war’, but he and other post-Republican writers ‘lost sight of the conditions under which they had ever survived without’ civic ‘heads and healers’ (p. 204). That is, in legitimising the Imperial present by making it continuous with the non-Imperial past, they ‘helped cement the Principate as Rome's governing form for centuries to come’ (p. 204). The flexibility of Republican terminology, in short, helped legitimise its political antithesis.

More striking, perhaps: M. shows that what scholars such as Philip Pettit and Quentin Skinner term as republicanism – or what M. calls, for analytic reasons, ‘Roman Republicanism’ – is a deeply flexible, and deeply underdetermined, array of ideas. Take the example of Cicero. Cicero made frequent use of ‘disease imagery’ in his writings (p. 78). He did so with respect to Catiline and Clodius, but he also did so in his more philosophical writings, as in Rep. 1.63 and Off. 1.85. While ‘exemplary statesmanship’ functioned analogously to the medical craft to yield ‘a viable solution to the decline of the body politic’ (p. 81), it did so by means of the political equivalent to particularly aggressive forms of treatment, namely violence (p. 85). Ciceronian political thought, in short, legitimised violence – both intra- and extra-judicial.

M. shows that, with respect to Cicero's rhetorical and conceptual legacy, ‘[t]he utility and danger of medical imagery lay in the ease with which it could be coopted in the service of nearly any political end’ (p. 88). This is not, of course, to suggest that philosophical republicanism necessarily entails such ambivalence; rather, it is to suggest that we should be cautious in seeking to make systematic normative use of ideas that ‘are not worked out in the mind of the philosopher, but rather in the shared experience of a messy and complicated world’ (p. 22). In Rome, Cicero's metaphors could ‘undermine the constitution they were invoked to protect’ (p. 196) – a fluidity echoed in the invocation of disease and illness metaphors, along with the health and purity of the body politic, by a range of modern-day populist opponents of constitutional government.