From the mundane to the philosophical: topic-modelling Voltaire and Rousseau’s correspondence

Voltaire and Rousseau’s correspondence are two fascinating collections which have perhaps not received the amount of attention than they could have due to the nature of these texts. Written over five decades, these letters cover a wide range of topics, from the mundanity of everyday concerns to more elaborate subjects. Getting an overall picture of these correspondences is challenging for the simple reader. This is unfortunate since these correspondences not only constitute a window into the private lives of Voltaire and Rousseau, or show an unfiltered expression of their respective thoughts, but they are also an example of the eclecticism professed by the philosophes. Fortunately modern computational techniques can truly help in providing an overview of the content of these letters and hopefully recapture – in a somewhat organized fashion – this very eclecticism of the Lumières. Thanks to the collaboration between the Voltaire Foundation and the ARTFL Project, I will be briefly discussing how topic-modeling can be used to draw an overall picture of these correspondences, and show a couple of examples of the model built from the Voltaire letters.

The ARTFL Project has long been engaged in exploring 18th-century discourses using digital tools, and the thematic opacity of correspondences is an ideal use-case for topic-modelling. This particular algorithm was designed to generate clusters of closely related words (or topics) by analyzing all word co-occurrences in any given corpus. Because these topics are extracted from their source texts, they are understood to describe the contents of the corpus analyzed. We recently released a topic-modelling browser – called TopoLogic – which was designed to explore such clusters of co-occurring words, and ran a preliminary experiment against the French Revolutionary Collection, the results of which can be seen here. When we built the topic models for Voltaire and Rousseau’s correspondences, we made sure to use the same parameters for both collections such that 40 topics (or discourses) were generated from each set of letters. We also only used those letters written by Voltaire on one side, and Rousseau on the other, hoping that we could perhaps make some comparisons between both models.

Let’s start with the Voltaire model, from which you can see the first 20 topics below:

As a first view into the topic model, the browser gives us the top 10 words for each topic, as well as their overall prevalence in the letters by Voltaire. From there we can further explore any topic, such as 16, which seems to map to Voltaire’s idea of the philosophe fighting against religious intolerance. By clicking on the topic however, we get an overview of how the topic is distributed in time, most important words in the topic, correlated topics, as well as documents where the topic is prominent (see figure below).

Let’s focus on several sections of this overview. We note below that the terms of philosophe and philosophie are weighted far more heavily than any other term, suggesting perhaps that all other words in this cluster may just constitute different characteristics of the philosophe in Voltaire’s eyes: religious concerns (prêtre, jésuite, religion, tolérance), attributes (honnête, sage), means of expression (article, livre).

All of these observations can of course be verified by exploring letters that feature topic 16 in a prominent way, which the browser does list. We can also see how the philosophe discourse evolves over the more than sixty years of Voltaire’s letters. Unsurprisingly, as his public involvement in religious affairs increases, the prevalence of such terms discussing his idea of the philosophe rises as well in his letters.

Among the discourses which tend to follow the same trend over time (see figure below), the cluster of terms related to justice (topic 5) stands out, once again showing that his public involvement is mirrored in his private correspondence. While these aspects are nothing really new, they provide for the prospective reader an easy way to find those letters that do discuss these topics.

Another interesting aspect of topic-modeling is that we can also examine the discursive make-up of any of Voltaire’s letters, and see if there are any other letters that share the same themes. Let’s examine Voltaire’s famous letter to Rousseau in which he mocks the citoyen de Genève’s position on the impact of literature in the second discourse (see figure below): ‘Les Lettres nourissent l’âme, la rectifient, la consolent’.

When we look at topical representation of this letter in the browser, we can note that the model found a number of different topics within this letter, which when combined do provide an overview of its contents. In it, Voltaire discusses – with much irony – his own experience as a writer (topic 33), which includes his role as historiographe du roi (topic 36), as well as the many controversies he was involved in (topic 10). He sarcastically laments the fact that he cannot afford to live with savages in a distant land (topic 25) because his health requires him to be treated by a doctor (topic 26 and 35). And as a whole, he defends the role of literature as a positive good for man (topic 0). Of course, one could argue that this topical structure is approximate, prone to discussion, and this is certainly true. However, this approximation is now available for all 15,000 letters, which then allows the computer to compare and group letters by this very topical structure. In this same document view, we can see documents which share a similar mixture of topics, such as a letter to Ivan Shuvalov from 1757 where Voltaire discusses his writing of history while displaying a very keen concern for the perception and impact of his writing, or another to D’Alembert where he complains about his bad health while stressing the importance of writing about useful things (‘il y avait cent choses utiles à dire qu’on n’a point dittes encore’).

One last aspect of the topic model is to examine the individual uses of words and the different contexts in which they are used. If we look at the uses of écrivain in the correspondences (see figure below), we can see how that its uses span across different types of discourses related to reason, the writing of history, or the public role of the writer. Looking at the actual word associations, we also note potentially interesting patterns. In the case of words that share similar topic distributions (used with a similar mix of discourses), a group of terms related to ignorance seems to dominate: fausseté, mensonge, ignorance, vérité, erreur, fable… This may allude to a sense of mission in Voltaire’s writings: to correct inaccuracies, to dispel lies, to reestablish the truth in the face of ignorance. Looking this time at words that tend to co-occur with écrivain, we get a very different picture, with terms that relate more to the activity of writing and the product of that writing. These two views on word associations do not contradict one another, but suggest different ways of thinking of the role of the écrivain as depicted in Voltaire’s letters.

To finish, let’s take a look at the topic model of Rousseau’s correspondence, and in particular how we can relate it to that of Voltaire. A quick overview of the first 20 topics in Rousseau’s letters reveals a similar – yet distinct – picture of the topical composition of his correspondence (see figure below).

Using the browser, we could track down Rousseau’s response to Voltaire’s criticism of the second discourse, and see if other letters discuss similar themes. This is all within the scope of this browser. For the sake of brevity however, and to show how topic models can be used to run comparative experiments, we wanted to focus on Rousseau’s usage of the word écrivain in order to see if and how it differed from what was suggested in the Voltaire model. As we can see below, Rousseau tends to use the term in similar contexts: the écrivain is invoked first and foremost as a conveyor of truth. But looking more closely at word associations, a distinctive pattern does emerge: such terms as lâche, haine, hypocrite, acharnement, or jalousie highlight a well-known trait of Rousseau, his paranoia in the face of his success as a writer. Clicking on any these words in the browser would allow a researcher to track down the individual uses of these terms as they relate to écrivain, and find those letters to discuss his persecution complex.

To conclude, we are well aware that any analysis provided here is purely built on the patterns derived from the topic models, and as such, remain unproven until verified by a close reading of the letters themselves. However, we hope to have shown how using a tool such as topic modeling can potentially provide new insights into the correspondences of Voltaire and Rousseau, or at the very least offer better guidance to scholars working on these two incredibly rich collections.

Clovis Gladstone

This article was first published in the Café Lumières blog in June 2020.

Clovis Gladstone’s Rousseau et le matérialisme appeared in Oxford University Studies in the Enlightenment 2020:8.


Prof. Catriona Seth, ‘Girls with Books. Reading, Contagion and Acquired Immunity in Eighteenth-Century Fiction’: The Inaugural Lecture of the eighth Oxford Marshal Foch Professor

Prof. Catriona Seth, outside the Taylorian Institution, Oxford. Photograph: Henrike Lähnemann.

On 9 May, Oxford’s eighth Marshal Foch Professor of French Literature gave her inaugural lecture to a packed hall at the Taylorian Institute. As she noted in her introductory remarks, the date is significant: 9 May is Europe day, commemorating the 1950 Schuman Declaration. What is also significant is that the eighth Marshal Foch Professor is the first to deliver her lecture at all: Catriona Seth is the first woman to hold the professorship.

Fellow of the British Academy, Member of the Académie Royale de Belgique, President of the Société Française d’étude du dix-huitième siècle, and Member of the Franco-British Council, Seth’s accolades testify to the respect for her research across Europe, and reflect her European academic career (which has included posts in the UK, France and Germany). She has published monographs on eighteenth-century French poets, on the history of smallpox, and on Marie-Antoinette; she has established the Pléiade editions of Laclos’s Les Liaisons dangereuses, and Germaine de Staël’s novels and De la littérature; she has published on the gothic novel, on women’s writing, on book illustration, and on the history of childhood, not to mention her article, with Katherine Astbury, on Bernardin de Saint-Pierre’s boxer shorts…[1] Beyond the headline undergarment, the latter is actually about a woman’s correspondence: that of Bernardin’s sister, Catherine. Indeed, much of Seth’s research to date has uncovered – and helped restore to the canon – the neglected history of what women read and wrote during the eighteenth and early nineteenth centuries. As the title of her lecture hinted, among many other things, Seth’s work has changed our understanding of the history of ‘girls with books’.

We were introduced to many such girls over the course of the hour: from Rousseau’s Julie and the women who devoured her story, to Laclos’s Merteuil who herself devoured La Nouvelle Héloïse (as well as every man, woman and child who crossed her path). Seth discussed less well-known women, too, showing that they were not only readers of novels, but often their champion and their raison d’être. Her analysis of Bougeant’s Voyage merveilleux du prince Fan-Férédin dans la Romancie (1735), for instance, highlighted that without women, this novel would not have existed. It was Prince Fan-Férédin’s mother who introduced him to novels and set off his travels in ‘la Romancie’, and without Bougeant’s female dedicatee, Madame C** B**, for whom he claimed to have written the novel, there would have been no text at all.

Weaving together some of the strands of her research, Seth merged close reading with cultural history, medical humanities, and the visual arts. Her argument centred on a metaphor and an analogy, both of which bridged the fields of medicine and literature. The metaphor (that reading the body is a metaphor for reading texts), and the analogy (that as inoculation can protect the body, so book-based instruction can protect the mind), are central to the two most famous eighteenth-century French epistolary novels: La Nouvelle Héloïse and Les Liaisons dangereuses. Both of these novels suggest that reading books in the right way can provide you with what Seth calls a ‘textually transmitted immunity’, to protect you from irksome textually transmitted diseases such as a romantic imagination or, worse, libertinage. The prophylactic needed is not a barrier, but an inoculation.

Gravelot (illustrator) and Mire (engraver), ‘L’Inoculation de l’amour’ (La Nouvelle Héloïse, 1761), Bryn Mawr Collections, accessed 12 May 2019.

Rousseau shows us this in La Nouvelle Héloïse. Wolmar attempts to cure Julie and Saint-Preux of their love for one another, for example, but never quite succeeds. As Julie contracts smallpox, recovers, but is scarred for life, so she manages to get over her love for Saint-Preux, but will always bear its scars; the physical trace of the disease – like the trace of her love for Saint-Preux – remains. Building on the argument of scholars such as, of course, Jean Starobinski, Seth explained that this is how Rousseau expected the novel to function: as a literary inoculation that infects readers with a carefully administered dose of morally harmful material, in order to protect them from greater, worldly hazards.[2] Since French society was rife with moral sickness, Rousseau believed, the only way to stem the contagion was to inoculate girls with books. However, the remedy was not fool-proof. Inoculation produced side effects, as Seth touched upon with reference to the work of Claude Labrosse on contemporary readers’ reactions to La Nouvelle Héloïse.[3] In their letters to Rousseau and their pilgrimages to the shores of Lake Geneva, Seth suggested that readers were not content with having received their treatment: they now wanted to see the doctor.

Side-effects were not the only problem; some readers signally failed to acquire immunity. Merteuil may have read and admired La Nouvelle Héloïse, as well as bundles of other people’s letters, but she failed to learn the lesson that her own letters could also be read in a way that her outward appearance could not… at least initially. The famous autobiographical letter 81, and letter 85 recounting her entrapment of Prévan, eventually uncover the true Merteuil behind her carefully constructed façade. In the end, Merteuil is not only publicly disgraced, but is also irremediably scarred by smallpox. Her punishment for failing to learn her lesson about the nature of texts, therefore, is to have her body finally betray her soul. Whether she likes it or not, everyone can now read her like a book. Seth argues that by leaving Merteuil vulnerable to smallpox (at a time when inoculation was becoming recognised as a cure), Laclos uses her as an illustration of what happens if one is not ‘inoculated’, by one’s reading, against the ills of society.

Seth closed by highlighting the present-day stakes of her argument, with a reference to Boko Haram’s abduction of over 250 school girls from their secondary school in Nigeria in April 2014. Citing New York Times journalist Nicholas Kristof (a peer from Seth’s years as an undergraduate at Magdalen College), Seth reminded us that still today, girls’ education is perceived as a threat by certain extremist groups because of its ability to transform society. The socially transformative potential of education is precisely what made it the site of countless disputes during the eighteenth century and, as Seth showed, these disputes show no sign of abating. Borrowing Kristof’s words, she noted, ‘the greatest threat to extremism isn’t a drone overhead but a girl with a book.’[4] The new Marshal Foch Professor thus concluded with a health warning, or rather a call to arms: ‘reading can seriously damage your ignorance’.

– Gemma Tidman

[1] For a list of Seth’s major publications, see her faculty profile. For the latter article, see Katherine Astbury and Catriona Seth, ‘Unblocking Enlightenment Loos, Bernardin’s Boxer Shorts and Other Day-to-Day Practicalities in Eighteenth-Century Normandy: A Whistle-Stop Tour of Catherine de Saint-Pierre’s Networks’, Nottingham French Studies, 54.2 (2015), 210–23.

[2] Starobinski, Le Remède dans le mal: critique et légitimation de l’artifice à l’âge des Lumières (Paris: Gallimard, 1989).

[3] Labrosse, Lire au XVIIIe siècle: La Nouvelle Héloïse et ses lecteurs (Lyon: Presses universitaires de Lyon, 1985).

[4] Nicholas Kristof, ‘Honoring the Missing Schoolgirls’, The New York Times (7 May 2014).

Rousseau on stage: Vitam impendere vero


Fig. 1: João Luís Paixão in the role of Pygmalion, in the research project Performing Premodernity’s production of Rousseau’s Pygmalion at the Castle Theatre of Český Krumlov 2015. Photo by Maria Gullstam.

In the Lettre à d’Alembert (1758) – Jean-Jacques Rousseau’s critical assessment of the Parisian theatre – the philosopher writes in a footnote: ‘[J]’ai presque toujours écrit contre mon propre intérêt. Vitam impendere vero. Voilà la devise que j’ai choisie et dont je me sens digne. Lecteurs, je puis me tromper moi-même, mais non pas vous tromper volontairement; craignez mes erreurs et non ma mauvaise foi. L’amour du bien public est la seule passion qui me fait parler au public.’[1] Rousseau claims to be writing with the ‘public good’ in mind, even though it might go against his own interests – such as his love for theatre and opera. When approaching Rousseau’s writings for and about theatre, we need to consider the often forgotten parts of his œuvre, as well as highlight the relation between these works and his political, musical, and literary writings. There are still numerous links to be made, and the task of making the connections is not always easy.

An illustrative example of this is Rousseau’s essay De l’imitation théâtrale – a translation and adaptation of parts of the tenth book of Plato’s Republic, with personal annotations by Rousseau himself. Originally, the text was composed in connection with the Lettre à d’Alembert in 1758, and Rousseau planned to publish the two texts together. However, he writes in the preface of De l’imitation théâtrale, ‘n’ayant pu commodément l’y faire entrer, je le mis à part pour être employé ailleurs’.[2] A few years later, Rousseau finds himself in a similar situation when publishing Julie, ou La Nouvelle Heloïse in 1761. Its preface in dialogue form had to be published separately from the novel, ‘sa forme et sa longueur ne m’ayant permis de le mettre que par extrait à la tête du recueil’, as its author writes in the avertissement of the separate publication.[3] Interestingly, he then attempts to publish it together with De l’imitation théâtrale, though without success.


Fig. 2: Laila Cathleen Neuman as Galathée and João Luís Paixão as Pygmalion, in the research project Performing Premodernity’s production of Rousseau’s Pygmalion at the House of Nobility (Riddarhuset) in Stockholm 2016. Photo by Maria Gullstam.

Two years later, in 1763, Rousseau has new plans to publish his ‘extrait de divers endroits où Platon traite de l’Imitation théatrâle’[4] – this time together with the Essai sur l’origine des langues and Lévite d’Ephraïm, and he starts to write a preface (Projet de préface).[5] But, just as in previous attempts, this third initiative to publish De l’imitation théâtrale is never finalised. Instead, the text is published on its own in 1764.

Rousseau saw fit to publish his essay on theatrical imitation together with texts ranging over a whole spectrum of topics and genres: his apparently complex treatise the Lettre à d’Alembert – criticising the Parisian theatre from both an anthropological and a moral perspective; the Préface to his novel Julie, ou La Nouvelle Heloïse, which when published separately in 1761 carried the subtitle Entretien sur les romans; further, the Essai sur l’origine des langues, which has strong connections to both Rousseau’s political writings (through its kinship with the Discours sur l’inégalité) and his writings on music (parts of the Essai started to develop in his unpublished response to Rameau’s accusations in the Erreurs sur la musique dans ‘l’Encyclopédie’); and finally, his moral tale Le Lévite d’Ephraïm. Thus, Rousseau could see connections between his essay on theatrical imitation and all these works. This is just one example amongst his many works for or about theatre that need to be reincorporated in his œuvre as a whole.

Rousseau loved drama passionately, he was aware of the consequences of attacking the Parisian theatre, and yet he criticised the Comédie-Française so fiercely in his Lettre à d’Alembert that this work’s inflammatory reputation still echoes in the twenty-first century. The Lettre’s notoriety has kept most theatre scholars from further exploring Rousseau’s own works for the stage, while the widespread labelling of Rousseau as an homme à paradoxes has every so often justified loose ends within Rousseau studies on the topic. Rousseau’s seemingly dual position in relation to theatre does entail numerous challenges. Our volume Rousseau on stage: playwright, musician, spectator does not claim to resolve these challenges, but to aim, nonetheless, at probing certain difficulties and starting to unravel others. The point of departure for Rousseau on stage is Rousseau’s passionate and double relationship to theatre as expressed and elaborated in the Lettre à d’Alembert, his theoretical texts on music and opera, his compositions for the stage and many descriptions of his experiences as a theatre-goer. Its authors and editors hope to add to the recent increasing interest in Rousseau as playwright, musician and spectator.

– Maria Gullstam and Michael O’Dea

[1] Jean-Jacques Rousseau, Œuvres complètes, ed. Bernard Gagnebin and Marcel Raymond, 5 vols (Paris, 1959-1895) (henceforward OC), vol.5, Lettre à d’Alembert, ed. Bernard Gagnebin and Jean Rousset, p.120.

[2] Rousseau, OC, vol.5, ‘Avertissement’ in De l’imitation théâtrale, ed. André Wyss, p.1195.

[3] Rousseau, OC, vol.2, Préface de la Nouvelle Héloïse, ou Entretien sur les romans, ‘Avertissement’, ed. Henri Coulet and Bernard Guyon, p.9.

[4] Rousseau, OC, vol.5, ‘Avertissement’ in De l’imitation théâtrale, p.1195.

[5] Neuchâtel, Bibliothèque publique et universitaire, MS R 91.

Nouvelles perspectives sur les manuscrits des Lumières

Dans le cadre superbe de l’hôtel de Lauzun, l’Institut d’études avancées de Paris a accueilli le 26 mai 2014 une journée d’étude destinée à faire le point sur certaines des découvertes récentes dans la recherche sur les manuscrits du Siècle des Lumières. Depuis quelques années, l’actualité attire l’attention sur certains manuscrits mythiques, comme celui d’Histoire de ma vie de Casanova qui a rejoint les collections publiques de la Bibliothèque nationale de France en 2010 grâce à un mécène, ou bien tout récemment, le rouleau des 120 journées de Sodome de Sade enfin de retour à Paris, pour y être exposé à l’automne au Musée des Lettres et Manuscrits.


Le manuscrit des 120 journées de Sodome

Les salles de vente bruissent des papiers des écrivains du XVIIIe siècle: ceux d’Emilie du Châtelet sont passés il y a peu aux enchères ainsi que dernièrement ceux de Portalis, l’un des auteurs du Code civil, dont la Cour de Cassation a réussi à acquérir le dossier génétique complet d’une de ses œuvres, la Consultation sur la validité des mariages protestants de France, qui comprend une copie au net annotée de la main de Voltaire.

Tandis que les manuscrits sortent des coffres et s’exposent derrière des vitrines ou sur des écrans numériques, de leur côté les chercheurs se lancent dans leur patiente analyse. Ce fut le but de cette journée, organisée par Nicholas Cronk, Nathalie Ferrand et Andrew Jainchill en collaboration avec l’équipe Ecritures du XVIIIe siècle de l’Institut des Textes et Manuscrits Modernes, de montrer tout l’intérêt, pour la compréhension et l’interprétation des œuvres, de l’étude de leurs états préparatoires et remaniés.

La page de titre des Considérations sur le gouvernement du marquis d’Argenson (1764)

La page de titre des Considérations sur le gouvernement du marquis d’Argenson (1764)

Ouvrant la matinée avec une intervention consacrée au marquis d’Argenson, Andrew Jainchill (Queen’s University, IEA) a présenté quatre états manuscrits de ses Considérations sur le gouvernement ancien et présent de la France, l’une des critiques les plus vives de la monarchie française au XVIIIe siècle – citée plusieurs fois dans le Contrat Social – dont il put interpréter l’évolution en fonction des additions de l’auteur dans ses différentes versions.

Après la théorie politique, c’est la philosophie naturelle de Mme du Châtelet qui fut l’objet d’une étude menée par Karen Detlefsen (U. of Pennsylvania) et Andrew Janiak (Duke U.), à partir d’une comparaison des manuscrits de ses Institutions de physique conservés à Paris et à Saint-Pétersbourg. Dans l’après-midi, Nicholas Cronk (U. of Oxford, IEA) a présenté les dernières découvertes dans le domaine voltairien, et a montré à quel point la recherche des manuscrits est féconde – y compris pour des auteurs canoniques comme Voltaire dont on croit tout savoir –, puisqu’on continue de découvrir de nouveaux manuscrits qui renouvellent les connaissances établies.

Au plus près du papier et des instruments d’écriture des auteurs, Claire Bustarret (CNRS-EHESS) a ensuite présenté les apports de la codicologie pour déterminer les campagnes d’écriture au sein de corpus manuscrits imposants, comme dans le cas des papiers de Condorcet. La journée s’est achevée par une intervention de Nathalie Ferrand (CNRS-ENS) sur l’importance croissante accordée aux manuscrits d’auteurs au sein des études dix-huitiémistes et sur le rôle qu’ont pu jouer les manuscrits des Lumières dans l’émergence progressive de la critique génétique au cours du XXe siècle, concluant par l’interprétation génétique d’une page de La Nouvelle Héloïse que Rousseau récrit en puisant au lyrisme du Tasse.

– Nathalie Ferrand, Ecole normale supérieure-CNRS

Caption: Page de corrections de La Nouvelle Héloïse de la main de J.-J. Rousseau

Caption: Page de corrections de La Nouvelle Héloïse de la main de J.-J. Rousseau