Mary W. Gray Professor of Mathematics and Statistics

American University Washington DC

mgray@american.edu

Émilie Du Châtelet – A Woman as a Scientist Helsinki, 1 April 2015

A mistress of Voltaire?

A Newtonian philosopher whose

insights and analyses were

appropriated by Voltaire?

An aristocratic dilettante with few if any real accomplishments?

A scientist whose understanding of fire and light not only surpassed that of Voltaire and others of her era but led to fundamental re-thinking of the phenomenon?

A devoted mother whose desire to educate her

son inspired her to write a Leibnizian physics textbook?

The translator of Newton’s Principia whose lucid commentary made its concepts accessible to a century of Francophone scientists?

As we know, Du Châtelet has been the subject of an opera, she also appears in a 2007French film for television, Divine Emilie, and of an episode of a 2005 British and American television series Einstein’s Big Idea, which credits Émilie’s insights as presaging E = mc2

A novelist has imagined that Émilie’s last child lived to maturity, leading the life that Émilie might had lived had her brilliance and energy been more conventionally directed:

Laurel Corona, Finding Emilie: A Novel, Gallery Books, New York, 2011

Another has written a book about her for young girls:

Jacqueline Duhême. Les passions d'Emilie : La marquise du Châtelet, une femme d'exception, Gallimard-Jeunesse, Paris, 2014.

At least four plays have recently been written about Du Châtelet in English alone:

Lauren Gunderson. Émilie: La Marquise Du Châtelet Defends Her Life Tonight, Samuel French, Inc., New York, 2010.

Du Châtelet contemplates her death

In Legacy of Light Karen Zacarias conjures a parallel between the work and childbirth concerns of Du Châtelet and those of a twenty-first century astronomer

Émilie’s Voltaire begins with Voltaire in a bathtub

and continues fancifully including the largely discredited image of Émilie in men’s clothing

Arthur Giron, Émilie’s Voltaire, Samuel French, Inc., New York, 2010

Jyl Bonaguro expanded the cast to include the mathematicians Clairaut and Maupertuis

as well as Voltaire and his valet Longchamp,

Saint-Lambert, the Marquis du Châtelet and the Duc de Richelieu

Jyl Bonaguro, Urania: The Life of Émilie Du Châtelet

As with many women in science, evaluations of Du Châtelet’s contributions tend to be bimodal – discounted or inflaed

The work is forgotten, ignored and/or characterized as

insignificant, derivative, lacking in originality and creativity

Or It is praised far beyond its merits

“magnificent that the dog can play the piano at all” syndrome

In accounts at both extremes there is excessive attention to physical characteristics, typical when female protagonists are discussed –

Quick, were Newton and Euclid short or tall, handsome or not, nattily

dressed or generally disheveled?

and to social life and surroundings at court and at Cirey

Her birth Her aristocratic, but not particularly wealthy, family connections A father nurturing by the standards of the time Her husband

Similar background Even temperament Happiest in the field with his military command Friendly relations with Voltaire

Her liaison with Voltaire But specifics are not so clear Details of initial meeting Fluctuating relations Close involvement with his difficulties with authorities and financial affairs

Her affair with Saint-Lambert With rival embellished accounts

Her “late-life” pregnancy and death

Outside the scope of Du Châtelet as a scientist French translation of Mandeville’s Fable of the Bees together with a preface

Discours sur le Bonheur Examien de Genese

Scientific writings Institutions de physique Réponse de Madame la Marquise du Chastelet,

a la lettre que M. de Mairan Dissertation sur la nature et la propagation du feu Principes mathématiques de la philosophie naturelle par feue

Translation of Newton and Commentary

How much of Voltaire’s work might be hers? How much of her work may be that of Maupertuis or Clairaut or another mathematician or physicist? Did that she devoted so much time to such activities as appearing in private productions of Voltaire’s plays and operas, gambling, and engaging in court politics provide distractions that may have kept her from more scientific work? Why did she decide to have a child, contemplating that complications might lead to her death? Are there works of hers that were lost after she died and never recovered? Are there unknown unknowns?

Tombe d’Émilie du Châtelet [1706-1749] Femme de sciences, traductrice de Newton, amie de Voltaire

Achieved some regard during her lifetime through correspondence with leading philosophers, physicists and mathematicians

Her contributions – however extensive - were quickly forgotten Voltaire wrote an extravagant Éloge, long on praise but short on credit for her accomplishments Principia translation was published only 10 years after her death and partly because of the interest in cosmology inspired by return of Halley’s comet

Twenty-first century recognition has in some cases been exaggerated – see in particular the E = mc2 attribution

Some have found her work “essentially derivative” of a number of her male contemporaries, particularly Voltaire

A number of her contemporaries give her credit for original thought - but not in the sense of proving new theorems, the usual criterion for being called a mathematician

In Du Châtelet’s short but colorful life there are many incidents that lend themselves to reporting from selective perspectives and several treatises the origin and fateof which are unclear.

We focus on three:

The publication of Éléments de la philosophie de Newton attributed to Voltaire but dedicated to Du Châtelet

The papers submitted to the 1736 Académie des Sciences prize essay

competition on the “Nature and Propagation of Fire” together with Institutions de physique

The posthumously published translation/commentary on Newton’s Principia Mathematica

Sifting out fact from fiction is made difficult by the scarcity of sources. We have Published and unpublished writings by Du Châtelet, especially the trove of writings found by Wade in St. Petersburg

Letters to and from friends and colleagues,

Voltaire’s problematic Éloge and Mémoire survivors write the history

Some of the approach of authors can be inferred from the titles they chose: Mitford: Voltaire in Love [1957] Edwards: The Divine Mistress: A Biography of Émilie du Châtelet, The Beloved of Voltaire [1970] Hamel: An eighteenth-century Marquise: a study of Émilie du Châtelet and her times [1910] Bodanis: Passionate Minds: Émilie du Châtelet, Voltaire, and the Great Love Affair of the Enlightenment [2006] Zinsser: Daring Genius of the Enlightenment (originally La Dame d’Esprit: A Biography of the Marquise Du Châtelet) [2006] Arianrhod: Seduced by Logic: Émilie Du Châtelet, Mary Somerville and the Newtonian Revolution [2012] Badinter: Émilie, Émilie: l’ambition feminine au XVIIIe [1983]

Roughly in order, the portrayals range from not very informative romanticism to a serious analysis of the work of Du Châtelet

Only Arianrhod addresses in any detail the actual mathematics

to be found in her works

Not all have much to say about the three topics of central interest, but when they do, the perspectives can be quite different

Edwards, Hame and Mitford are the least informative about Du Châtelet as philosopher and scientist

Badinter and Zinsser have the most to say about her work as well as her life

Mitford and Edwards focus heavily on the relationship with Voltaire

Hamel relies heavily on the letters and other writing of those from the aristocratic and intellectual assemblages she frequented

Edwards: In his Mémoire Voltaire notes that he “failed to mention that he and Du Châtelet also collaborated on a major project, a long and intricately detailed treatise on the work of Sir Isaac Newton.”

Voltaire might be referring to Élements, where in the frontispiece we see Du Châtelet hovering above, but no acknowledged co-authorship. Or he might be asserting his role in her later independent work, or the part Du Châtelet played in his separate submission to the Académie contest. Edwards largely credits Voltaire as author, citing her apprenticeship as encouraging her to continue her studies, but his claim that it was easy to identify her contributions, resulting in her widespread recognition as “an independent thinker, a woman of powerful intellect” appear inconsistent with his attribution.

Was Voltaire motivated by his association with Newtonians during his exile in England, did he want to add to his reputation as philosopher, poet, dramatist and historian? Or did he take up the project to engage and maintain the interest of Du Châtelet at the beginning of their relationship? Although Élements was intended for a wider audience, did Voltaire actually undertake sufficient study of the algebra and geometry of the original to be the principal author? Does his glowing “Minerve dictait et j’ecrivais” imply co-authorship as well as acknowledgement of assistance/ Or was omitting recognition of Du Châtlet as co-author necessary to give the work credibility – for at the time who could take seriously the contribution of a scandalous woman pretending to be a scientist?

Mitford – and recall her book is Voltaire in Love – says Voltaire performed a service to France by forcing himself to understand the original so that he could make it clear to others. On the other hand, Clairaut later advised Voltaire to devote his time to philosophy and poetry and give up science, in which he would never rise above mediocrity.

Considering that she had completed her translation of the Aeneid at about the same time, Du Châtelet’s Latin as well as her understanding of mathematics was probably superior to Voltaire’s.

Boldanis identifies Du Châtelet as a co-author, but his evaluations are generally overly generous to her without specific analysis of why, other than referring to her comments that she decided to write her own original works of natural philosophy because of the “false steps” and “confused ideas” of another – presumably Voltaire – that she had previously encountered. Although focusing primarily on the social context of her work, Hamel also raises the question of joint authorship.

Others are not so wedded to the idea of co-authorship. The Zinsser-edited Selected Philosophical and Scientific Writings of Émilie Du Châtelet, for example, does not include Élements as a work of Du Châtelet.

By the mid-1730’s Du Châtelet and Voltaire were established at their retreat at Cirey, where Voltaire presided over elaborate experiments, focused in particular on efforts to

show that fire was actually matter, that is, that it had weight. Much havoc, but no definite conclusions resulted. Only Zinsser has detailed – if imaginative - descriptions, concluding that Voltaire intended all of the elaborate equipment for his own use, with Du Châtelet as an assistant, not as a partner. Increasingly disenchanted, she

worked in secrecy and at night to try to substantiate her own view of the nature of fire and of light.

Although accounts of the two experiments differ, most biographers emphasize her courage in proceeding on her own, with even those most inclined to see her work as derivative considering her Académie submission as totally independent – an 84-page document produced in a month. Would Voltaire have tried to sabotage her work had he known? Did she fear humiliation or anticipate sweet revenge?

The two independent solutions submitted to the Académie received what we might call honorable mention. Both were Newtonian in approach whereas the

three winners, among them Euler, adhered to the Cartesian view prevalent in the Académie at that time.

Between the submission and preparing the work for publication the following year, Du Châtelet had been studying the work of Leibniz and Wolff in preparation for writing her Institutions de physique and sought unsuccessfully to alter the Newtonian formulation f = ma to the vis viva formulation f = ma2 that appeared in Institutions.

This created a substantial controversy in the French scientific

community, including a dispute with the Académie secretary Mairan.

Although at the time Du Châtelet received credit for her contribution to the evolution of the vis viva theory, biographers tend to ignore or else to exaggerate the effect of her influence seeing her work as precursor to Einstein or even as foundational to the technologies of the Internet.

Du Châtelet’s announced intention in writing Institutions de physique was to provide a textbook for her young son. The less scientifically inclined of her biographers refer to it merely as a book dedicated to him.

Even though presented as an attempt to reconcile complex ideas from leading theories of the time, it was broadly well received by the educated populace and scientific journals but fell out of use as physics moved from natural philosophy to a experimental focus. A Hagengruber-edited volume has analyzed its influence in the Newton/Leibniz debate.

Arianrhod deals best with the discussion in the last chapter of vis viva that captured the attention of the scientific community as a skillful blend of the Newtonian and Leibnizian approaches. It was considered by Voltaire to be an abandonment of Newton.

The publication of Institutions de physique marked a coming of age and solidified her growing reputation among the Intellectuals of the Enlightenment in the judgment of those of her biographers who seriously analyzed her work.

After the publication of Institutions de physique, Du Châtelet turned to what began as a translation but became much more as she struggle frantically to finish the Commentary as she foresaw her death.

What should dominate an assessment of the originality of her work are the Institutions de physique and the Principia translation and commentary as it is very clear that Voltaire had very little to do with either.

Serious biographers emphasize the accomplishment that her “Newton” represents, not only as a translation but as a commentary. Authors’ discernment of the significance of Du Châtelet’s work can be initially recognized in part by whether they refer to the end product as only a translation or whether then focus on the commentary, which occupied her up until her death in September 1749. Her extensive understanding of the mathematics of the original was developed through long and intensive study with Maupertuis, König, Jacquier and Clairaut. The translation was granted permission to be published in 1746 and was substantially completed by the next year.

Three sources of Newton were available in France in the 1740’s 1) The vernacular popularization of Algarotti and the earlier

Voltaire/Du Châtelet Éléments 2) Specialized Mémoires by Académie members covering

specific points

3) Newton’s own writings in Latin and English, very

difficult to penetrate by even the well-trained

Did Du Châtelet feel that the Éléments needed to be supplemented by the propagation of Newton’s actual original work?

Or was it the residual belief that her contribution to Éléments had not been adequately

recognized?

Or was it the belief that as a service to science and satisfaction to herself she was

compelled to bring clarity and accessibility to Newton’s work?

The Principia project had been taken up in the early 1740’s, put aside and revived several times. While it was in progress Du Châtelet also wrote Discours sur la Bonheur, worked on her five volume Examen de Genese and was heavily involved in the financial affairs of her husband’s family. With the complete of the translation came the conviction that more was needed – under the premonition of an early death. The nature of the Du Châtelet/Voltaire relationship had changed from that of lovers to that of sometimes contentious friends and she had begun a liaison with Saint-Lambert. At what was for the mid 18th century an advanced age she became pregnant. Her husband rushed to be with her long enough to give the color of fatherhood to the expected child, but subsequently neither he nor Saint-Lambert nor Voltaire concerned himself much with the child, who died before the age of two.

Overview of the theory of gravity Summary of the more complex topics of the Principia Chapter on the shape of the earth, based on the work by Maupertuis and Condamine Daniel Bernoulli’s work on tides Some topics from astronomy Some extracts from the mathematical work of Clairaut Summary of the work of Newton and his earliest Continental followers Converted Newton’s geometric approach to one that was calculus based Du Châtelet deposited with the king’s library her notebooks showing her progress on the work, authenticating it through drawing, additions, and revisions. Unfortunately eight volumes of her correspondence with Voltaire were apparently destroyed, perhaps by Saint-Lambert, with whom they were reported to have been left.

There are fanciful descriptions of varying accuracy of Du Châtelet’s last days and death that she delivered her child almost unnoticed and placed her upon a geometry book

that Voltaire threw himself down the stairs in his grief – a few day after relating how much more difficult had been his birth pangs with his Catalina

that Saint-Lambert cradled her head as she struggled with her last breath

Some biographers end their accounts abruptly with her death

Others present a synopsis of the remainder of Voltaire’s life, including his return to his affair with his niece and an unhappy sojourn in Berlin

Still others relate Saint-Lamber’st success in acquiring another mistress from a well-known figure (Rousseau)

As noted, Voltaire’s self-serving Élage and Mémoire created an image of Du Châtelet that it took centuries to overcome

Ten years after her death, inspired perhaps by the return of Halley’s comet, Clairaut assembled her papers and oversaw the publication of her “Newton.”

Diderot and d’Alembert credited her for her contributions to the knowledge of Newton through her translation and Commentary, but she was soon forgotten.

In the books considered, there is not, in my opinion a feminist perspective on Du Châtelet’s work per se, nor really on her career. Mitford’s portrayal of her as a flighty socialite and scientific dilettante being the furthest from such.

Unlike Kovalevskaya, Germain, and Noether, Du Châtelet has never become a major icon among women in the mathematical sciences

Why Lack of discernable original contributions as a mathematician, certainly Tendency to avoid as heroines those who may be considered as coquettes or society dilitantes no matter their contributions No discernable concern for the position or involvement in science of other women or other involvement in “feminist” causes No concern for the education or advancement of women, including her daughter

Is Discours sur le bonheur a “revolutionary cry for female independence” as charactierzed by Arianthod, who does see her as a heroine for young women and for “any thinking person” as Voltaire predicted?

Not to my knowledge or observation