Disapproval of acting and the theatre was a distinguishing Roman characteristic, in the eyes of many ancient authors. The significance Romans attached to the different ways actors were viewed in Greece and in Rome is indicated by Cornelius Nepos, in the preface to his Lives, where he sets out some of the principal contrasts between Greek and Roman culture ... While Greeks admired actors, according to Nepos, to display oneself on stage, to make a spectacle of oneself, was considered by Romans to be shameful. Other writers, too, saw differing attitudes to the theatre as a significant indicator of the contrast between Greek and Roman culture.

The rhetoric of Roman moralising has often seemed alien to modern readers. This book, in linking together studies of apparently diverse topics, might be seen as appropriating a trope of Roman moralistic discourse, presenting arguments concerning different subjects as parallel so that they may serve to reinforce one another. A better understanding of this and similar literary devices, as they operate in Roman moralising texts, can help us to make sense of some features of those texts which modern readers have found puzzling. We begin with an apparently bizarre example of this kind of rhetoric (included in the book of rhetorical exercises put together by the elder Seneca).

Pleasure was a problem for members of the Roman elite – or so moralists felt. In his treatise on the good life, Seneca stresses the insidious threat posed by the attractions of sensual pleasure, while asserting that only the subhuman will want to surrender themselves completely ... Seneca’s language presents pleasure as fluid, both engulfing and invading its hapless victims. His insistence on its seductive dangers could be read as betraying a certain fascination with pleasure.

The Romans laid claim to a particular pre-eminence in the spheres of both fighting and morality. Seneca presents the activities of the guardian of morals as parallel to those of the general; each has made a vital contribution to the res publica. As a Stoic, Seneca was committed to the notion that the ties which bind all human beings to one another transcend those which bind the individual to any particular state, and yet for the Romans there was only one res publica, Rome itself. By using the traditional vocabulary of Roman moralists, by taking as examples the figures of Scipio and Cato, Seneca situated his text in a long line of Roman moralising. Seneca wrote his moral and philosophical works over two hundred years after the time of the elder Cato, who lived in the second century BCE; Cato’s writings in turn referred back to the virtues of still earlier Romans, maiores nostri (’our ancestors’). The highpoint of Roman moral virtue was always already situated in an idealised past.

The immorality of the ancient Romans is a commonplace in modern representations of Roman antiquity. In nineteenth-century history painting, twentieth-century sword and sandal movies and twenty-first-century TV shows alike, inebriated Roman voluptuaries lounge on their couches surrounded by gleaming marble, while they savour exotic foods and grope scantily dressed women and boys.Romans behaving badly certainly have box-office appeal but the details of their excesses in the modern imaginary are deeply rooted in the preoccupations of cultural commentators in Roman antiquity. The speeches of Cicero, the histories of Sallust, Livy and Tacitus, the philosophical works of Seneca, the Elder Pliny’s observations about the natural world – all these texts (and more) return obsessively to the vices of their authors’ fellow Romans, charting their sexual misbehaviour, their insatiable desire for luxury, their inability to subordinate their own pleasure to the public good.

The ancient Romans have been so domesticated that many modern western men (fewer women, perhaps) have been able to imagine themselves, their rusty Latin refreshed, easily adapting to life in the time of Cicero or the younger Pliny. But language is not the only barrier which separates us from the Romans. Entire vocabularies of gesture differ from one culture to another. For Romans, a particular physical movement could have a meaning quite at variance with one a modern Briton might attribute to it – even indicating a category of behaviour for which we have no close equivalent.

In 62 BCE, a young and politically ambitious Roman aristocrat, Publius Clodius, is said to have disguised himself as a women in order to infiltrate the rites of the Bona Dea, which it was sacrilege for men to observe. His purpose, according to his detractors, was to seduce the wife of Julius Caesar, the Pontifex Maximus, in whose house the ceremony was taking place. A man dressed as a woman, the profanation of religious rites, adultery with the wife of one of the leading men in Rome and the adulterer already notorious for his pernicious and disruptive political dealings – this incident, related or alluded to by numerous Roman authors, summed up the disorder of the final years of the republic. For Roman writers, adultery among the elite was a telling symptom of disease in the body politic.

What should we make of the glaring absence of the emperor Nero from Seneca’s Epistulae morales – not mentioned once in 124, often lengthy, letters, written by a man who had been for many years one of his closest associates? Although Seneca does sometimes allude to the question of how frank advice may be offered to the powerful, the letters barely touch on imperial politics, beyond advising their addressee that he would be better off withdrawing from the public sphere. Yet if Nero is not present explicitly, there are a number of respects in which Nero’s domination of others as well as his failure to exercise control over himself are constructed as implicit and potent anti-models in the letters. When Seneca reflects on the dynamics of vice in its more florid and imaginative forms (the examples analyzed here are letters 90 and 114), his terms frequently resonate quite specifically with ancient accounts of Neronian Rome (notably those of Tacitus and Suetonius) and other works of Neronian literature (particularly Petronius and Persius). As it turns out, highly refined vices even play a notable role in Seneca’s model of the development of philosophy.