For approximately the last thirty years, Cicero’s reputation as a philosopher has been rising after close to a century of very low esteem.Footnote ¹ The alleged reasons for this disrepute are numerous and varied. Cicero was Roman, and Romans were thought to be neither scientific nor philosophical. He wrote in Latin, when the genuine language of philosophy was and is Greek. No original thinker, he was not so much a philosopher as translator and compiler, pasting together various philosophical works from the second and first century bce. This he did in his spare time, for Cicero was an amateur philosopher. His main pursuits were politics and judicial advocacy. When he turned to philosophy, he was content to adopt a form of eclecticism amenable to his own changing status in the troubled last decades of the Roman Republic. This short introduction won’t be covering Cicero’s philosophical works and their context (for which the reader should consult Chapter 1); it aims only to present the various and complementary ways in which this Companion, building on earlier studies, may answer these charges and allow us to gain a more accurate and richer picture of Cicero as a philosopher.

First, one must emphasize how crucial Cicero’s philosophical writings were to the history of Western philosophy and culture. Cicero is one of our best sources of information about the doctrines and debates of the Hellenistic philosophers whose works have been almost entirely lost. About his teachers Philo of Larissa and Antiochus of Ascalon we would know next to nothing were it not for Cicero’s dialogues. They are also our only sources about crucial physical or ethical tenets of the Stoics, the Epicureans, and the New Academy, and about many Hellenistic debates between these three schools.Footnote ²

Cicero is also the creator of a considerable proportion of the Latin philosophical vocabulary, which had a major imprint on the history of Western philosophy lasting to our own day. In Chapter 5, Carlos Lévy analyzes Cicero’s aims and methods in his translations from Greek into Latin. Cicero’s contributions covered the fields of epistemology, ethics, and physics, and helped bequeath us terms such as the “individual” and “will.”

Future generations from Seneca onwards regarded Cicero as an important philosopher whose philosophical works and positions were important in themselves. In Chapter 10, Anne-Isabelle Bouton-Touboulic focuses on Augustine’s significant debts in style and substance to Cicero’s philosophical writings. In Chapter 17, Daniel J. Kapust surveys the attitudes toward Cicero of a large number of eighteenth-century philosophers and political thinkers on a range of topics including ethics, rhetoric, civil religion, law, and the value of glory.Footnote ³ While authors in other periods have also turned to Cicero’s philosophical writings with profit,Footnote ⁴ Cicero’s thought most significantly contributed to the work of philosophers during Late Antiquity and the eighteenth-century Enlightenment.

But Cicero is not worthy of consideration merely because of reception history. Cicero’s contribution to the topics just mentioned are important in their own right. First, his De republica (On the Commonwealth), De legibus (On Laws), and De officiis (On Duties) are major works in the history of political philosophy.Footnote ⁵ Chapters 12, 14, and 15 by Gretchen Reydams-Schils, Walter Nicgorski, and Jed W. Atkins, respectively, survey Cicero’s views on human social relationships and community; his definition of res publica through liberty, his conception of equality and justice and of the best form of government; his discussions of imperialism, of justified and unjustified war, and of cosmopolitanism. While often drawing on Stoicism for these topics, Cicero offers his own views, which were informed by his study of philosophy and, perhaps above all, his experience as a Roman statesman. Moreover, as Martha C. Nussbaum shows in Chapter 18, Cicero’s discussions of cosmopolitanism, the duties of justice, and the conduct of warfare have vital relevance to current debates.

Nussbaum also devotes attention to practical ethics, where Cicero made original, albeit often overlooked, contributions on friendship and old age, which are still applicable to contemporary concerns. While practical ethics is often reduced to a personal search for peace of mind, Cicero’s approach stands out for its focus on the social and political roots and implications of emotions or duties (as emphasized in Chapters 10, 12, and 18). In the Tusculan Disputations, Cicero deals with fear (especially of death) and grief, and, as Sean McConnell shows in Chapter 10, he adopts a pragmatic approach, which can be seen as a distinctive aspect of his philosophical practice.Footnote ⁶

In fact, political philosophy and practical ethics are not so much discrete topics for Cicero as perspectives central to all his works. Cicero does not practice philosophy in a social void. In Chapter 1, Claudia Moatti puts his whole philosophical oeuvre into the context of the late Roman Republic and emphasizes his project of rationalizing Roman culture and politics. Cicero is not interested in theoretical elaboration in itself, let alone innovation, but concerned “with how the activity of philosophy might fit in with broader Roman social and cultural norms,”Footnote ⁷ and also claims to create a new style of doing philosophy.Footnote ⁸ This is why Cicero insists on judging philosophical doctrines not only on the basis of their consistency or adequacy to the facts, but also through the manner of discourse their proponents adopt and the efficiency of their arguments both inside and outside philosophical schools.Footnote ⁹ Consequently, Cicero’s letters and speeches are also relevant for understanding Cicero as a philosopher, as shown in chapters 3 and 4, by Sophie Aubert-Baillot and Catherine Steel. The letters offer insights into the elaboration of Cicero’s positions and testify to the experimental dimension of most philosophical doctrines in this corpus. The speeches use philosophy against Cicero’s opponents but also as an implicit source of insights about political values and threats. This use of philosophy is theorized by Cicero in his dialogue De oratore (On the Orator) written in 55, as shown by Gary Remer in Chapter 13. Challenging both philosophical censures of rhetoric and widespread beliefs about philosophy’s uselessness, Cicero conceives of rhetoric, politics, and philosophy as so interconnected that they are, or at least should be, a unity under the rubric “eloquence.”

Cicero’s later philosophical dialogues, written in the 40s under Caesar’s dictatorship, are obviously not public speeches, but he conceived them as a continuation of eloquence and politics (from which he was forced to retire after Caesar’s victory over Pompey) by other means.Footnote ¹⁰ It is crucial to take this agenda into account if we are to read Cicero’s dialogues on their own terms. In Chapters 8 and 9, Clara Auvray-Assayas and Elisabeth Begemann show how preserving human responsibility both at the individual and the political level is a crucial issue in Cicero’s approach to cosmology and theology. In De natura deorum (On the Nature of the Gods), Cicero emphasizes the historical, anthropological, and psychological aspects of Greek theology and uses skeptical arguments to define precise limits for political thinking on religion, while De divinatione (On Divination) and De fato (On Fate) can be read as seeking to combine Greek thought and Roman practice and as exhortations to act in the service of the res publica after the death of Caesar.

In response to all of these arguments for treating Cicero as an important philosopher, one might counter that he was content with an eclectic philosophy suited to the practical concerns of his Roman readers and that this is a long way from offering a systematic doctrine addressing philosophy’s core issues in ontology and epistemology. Recent scholarship has shown, on the contrary, not only that Cicero’s approach to philosophy as described so far is consistent throughout his late dialogues, and perhaps even his whole oeuvre,Footnote ¹¹ but also that it is all of a piece with his affiliation to the New Academy. Cicero, like many other ancient and modern thinkers, has suffered greatly from the widespread disrepute of skepticism as a philosophy. But shunning new doctrines in favor of a critical survey of available ones, putting them into their cultural context, or assessing their practical implications are not the marginal approaches of an outsider but part and parcel of Cicero’s skeptical practice of philosophy.

Cicero often praises the New Academy for preserving the freedom (libertas) of judgment of its followers, unlike other schools that submit them to an authority: such a conception of philosophy is both epistemological and pedagogical, but also has political implications since libertas was an important republican value.Footnote ¹² Yet there is still much debate about which type of skepticism should be attributed to Cicero. This problem is addressed by Tobias Reinhardt in Chapter 7, which shows that Cicero’s stance in his Academica (Academic Books) shares certain features with mitigated skepticism but is formally a radical skepticism, and that his dialogues are unique sources about the enactment or the living practice of an Academic skeptical stance.Footnote ¹³

Did Cicero really invent this Academic stance or did he borrow it from his Academic teachers? Was his epistemological contribution essentially literary (translating, selecting characters and a setting for each dialogue, adducing prefaces and Roman examples)Footnote ¹⁴ or really philosophical? A very promising line followed by recent scholarship has consisted in showing that this opposition misses the point. Cicero wrote dialogues for philosophical reasons. In Chapter 2, Charles Brittain and Peter Osorio present a few examples from the late and early dialogues to argue that Cicero’s texts systematically enact, as well as represent, an Academic pedagogical methodology. While the dialogues mostly present doctrines which are not Cicero’s own, they stage or frame original and searching philosophical debates between these doctrines.

Cicero’s dialogues on ethics are a very good example, as shown by Raphael Woolf in Chapter 11: in De finibus (On Ends), Cicero writes as a skeptic, using the arguments to encourage his readers to consider the importance of accounting for a plurality of ethical goods and whether, once we do that, we can still usefully adhere to a “full-fledged” ethical theory. Thus, Cicero’s philosophical stance can be captured only from a careful reading of each dialogue as a whole.Footnote ¹⁵ Cicero’s dialogues must be read in the same manner as Plato’s dialogues have been read during the last thirty years or so, that is to say as philosophical dialogues, in which no character (even a character bearing his name)Footnote ¹⁶ can be assumed to be a straightforward mouthpiece of the author and each argument must be read in its dramatic context. As a matter of fact, as shown by Malcolm Schofield in Chapter 6, Cicero himself identified with Plato in all his richness and abundance as a writer, thinker, and model for the politically engaged intellectual, but the imprint of Plato on Cicero’s works evolved and is still much debated.

This introduction has tried to present the various ways in which Cicero has been read anew as a genuine philosopher during the last three decades or so, and how these approaches are represented in the eighteen chapters of this Companion. Our goal is to offer an overview and assessment of recent research on Cicero’s philosophy and to encourage new research in this area. These lines of inquiry have been and are being pursued by many scholars all over the world and will surely not converge into one single picture of Cicero’s philosophy. Some scholars focus only on Cicero’s “strictly” philosophical dialogues, many take into account some or all of his other writings, while others study their various uses through different periods and cultures. Some scrutinize Cicero’s arguments against the background of his Greek sources, others reconstruct his cultural and political agendas in the context of the late Roman Republic, and others emphasize their relevance to contemporary philosophical debates. Some view Cicero’s Academic stance as radically skeptical, while others insist on the imprint of Stoicism or of Plato on many of his positions. Some emphasize Cicero’s continuity across his entire body of philosophical writing, whereas others point out the various changes in style or substance between these works. Despite this diversity, all these approaches share the fundamental conviction that Cicero’s philosophy will not be recovered against or at the expense of his other achievements and identities as a writer, advocate, politician, and Roman man of the first century bce, but only in coordination with these other dimensions of his life. There is no one single way of reading Cicero as a philosopher; it clearly requires us to widen and diversify our practice and notion of philosophy. Renewed attention to Cicero can thus benefit the discipline of philosophy today, just as it did in the eighteenth century. Let us hope our century too will be Ciceronian.