Émilie Du Châtelet
   HOME

TheInfoList



OR:

Gabrielle Émilie Le Tonnelier de Breteuil, Marquise du Châtelet (; 17 December 1706 – 10 September 1749) was a French
mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...
and physicist. Her most recognized achievement is her philosophical magnum opus, ''Institutions de Physique'' (Paris, 1740, first edition; ''Foundations of Physics''). She then revised the text substantially for a second edition with the slightly modified title ''Institutions physiques'' (Paris, 1742). It circulated widely, generated heated debates, and was translated into German and Italian in 1743. The ''Institutions'' covers a wide range of topics, including the principles of knowledge, the existence of God, hypotheses, space, time, matter and the forces of nature. Several chapters treat Newton's theory of universal gravity and associated phenomena. Later in life, she translated into French, and wrote an extensive commentary on,
Isaac Newton Sir Isaac Newton () was an English polymath active as a mathematician, physicist, astronomer, alchemist, theologian, and author. Newton was a key figure in the Scientific Revolution and the Age of Enlightenment, Enlightenment that followed ...
's ''
Philosophiæ Naturalis Principia Mathematica (English: ''The Mathematical Principles of Natural Philosophy''), often referred to as simply the (), is a book by Isaac Newton that expounds Newton's laws of motion and his law of universal gravitation. The ''Principia'' is written in Lati ...
''. The text, published posthumously in 1756, is still considered the standard French translation to this day. Du Châtelet participated in the famous ''
vis viva ''Vis viva'' (from the Latin for "living force") is a historical term used to describe a quantity similar to kinetic energy in an early formulation of the principle of conservation of energy. Overview Proposed by Gottfried Leibniz over the period ...
'' debate, concerning the best way to measure the force of a body and the best means of thinking about conservation principles. Posthumously, her ideas were represented prominently in the most famous text of the
French Enlightenment French may refer to: * Something of, from, or related to France ** French language, which originated in France ** French people, a nation and ethnic group ** French cuisine, cooking traditions and practices Arts and media * The French (band) ...
, the ''
Encyclopédie , better known as ''Encyclopédie'' (), was a general encyclopedia published in France between 1751 and 1772, with later supplements, revised editions, and translations. It had many writers, known as the Encyclopédistes. It was edited by Denis ...
'' of
Denis Diderot Denis Diderot (; ; 5 October 171331 July 1784) was a French philosopher, art critic, and writer, best known for serving as co-founder, chief editor, and contributor to the along with Jean le Rond d'Alembert. He was a prominent figure during th ...
and
Jean le Rond d'Alembert Jean-Baptiste le Rond d'Alembert ( ; ; 16 November 1717 – 29 October 1783) was a French mathematician, mechanician, physicist, philosopher, and music theorist. Until 1759 he was, together with Denis Diderot, a co-editor of the ''Encyclopé ...
, first published shortly after du Châtelet's death. She is also known as the intellectual collaborator with and romantic partner of
Voltaire François-Marie Arouet (; 21 November 169430 May 1778), known by his ''Pen name, nom de plume'' Voltaire (, ; ), was a French Age of Enlightenment, Enlightenment writer, philosopher (''philosophe''), satirist, and historian. Famous for his wit ...
. In the two centuries since her death, numerous biographies, books, and plays have been written about her life and work. In the early twenty-first century, her life and ideas have generated renewed interest.


Contribution to philosophy

Du Châtelet wrote a number of significant scientific and philosophical works, including an essay on the nature of fire which was published by the Royal Academy of Sciences in Paris, as well as her ''magnum opus'', the ''Institutions de physique,'' which was also translated into German and Italian. In addition to her original works, Du Châtelet also produced influential translations of major works by authors such as Bernard Mandeville and
Isaac Newton Sir Isaac Newton () was an English polymath active as a mathematician, physicist, astronomer, alchemist, theologian, and author. Newton was a key figure in the Scientific Revolution and the Age of Enlightenment, Enlightenment that followed ...
. Because of her well-known collaboration and romantic involvement with
Voltaire François-Marie Arouet (; 21 November 169430 May 1778), known by his ''Pen name, nom de plume'' Voltaire (, ; ), was a French Age of Enlightenment, Enlightenment writer, philosopher (''philosophe''), satirist, and historian. Famous for his wit ...
that spanned much of her adult life, her accomplishments have often been subsumed under his, and historical accounts have often mentioned her only within the context of Voltaire's life and work during the period of the early French Enlightenment. However, the nature of their relationship was collaborative. Voltaire acknowledged that du Châtelet's mathematical expertise was a crucial aid in understanding the technical parts of Newton's ''Principia'' while writing his popularization of the Newtonian philosophy, ''Éléments de la philosophie de Newton''. Recently, scholars have taken a renewed interest in du Châtelet, which has resulted in a renewed appreciation of her original contributions. Historical evidence indicates that her work had a very significant influence on the philosophical and scientific conversations of the 1730s and 1740s – in fact, she was famous and respected by the greatest thinkers of her time.
Francesco Algarotti Count Francesco Algarotti (11 December 1712 – 3 May 1764) was an Italian polymath, philosopher, poet, essayist, anglophile, art critic and art collector. He was a man of broad knowledge, an expert in Newtonianism, architecture and opera. He w ...
styled the dialogue of ''Il Newtonianismo per le dame'' based on conversations he observed between du Châtelet and Voltaire at Cirey. Du Châtelet corresponded with the renowned mathematicians
Johann II Bernoulli Johann II Bernoulli (also known as Jean; 18 May 1710, Basel – 17 July 1790, Basel) was the youngest of the three sons of the Swiss mathematician Johann Bernoulli. He studied law and mathematics, and, after travelling in France, was for five y ...
and
Leonhard Euler Leonhard Euler ( ; ; ; 15 April 170718 September 1783) was a Swiss polymath who was active as a mathematician, physicist, astronomer, logician, geographer, and engineer. He founded the studies of graph theory and topology and made influential ...
, early developers of calculus. She was also tutored by Bernoulli's prodigy students,
Pierre Louis Moreau de Maupertuis Pierre Louis Moreau de Maupertuis (; ; 1698 – 27 July 1759) was a French mathematician, philosopher and man of letters. He became the director of the Académie des Sciences and the first president of the Prussian Academy of Science, at the i ...
and
Alexis Claude Clairaut Alexis Claude Clairaut (; ; 13 May 1713 – 17 May 1765) was a French mathematician, astronomer, and geophysicist. He was a prominent Newtonian whose work helped to establish the validity of the principles and results that Sir Isaac Newton had o ...
. Frederick the Great of Prussia, who re-founded the Academy of Sciences in Berlin, was her great admirer, and corresponded with both Voltaire and du Châtelet regularly. He introduced du Châtelet to Leibniz's philosophy by sending her the works of Christian Wolff, and du Châtelet sent him a copy of her ''Institutions''. Her works were published and republished in Paris, London, and Amsterdam; they were translated into German and Italian; and, they were discussed in the most important scholarly journals of the era, including the '' Memoires des Trévoux'', the ''
Journal des Sçavans The (later renamed and then , ), established by Denis de Sallo, is the earliest academic journal published in Europe. It is thought to be the earliest published scientific journal. It currently focuses on European history and premodern literatu ...
'', the '' Göttingische Zeitungen von gelehrten Sachen'', and others. Many of her ideas were represented in various sections of the ''Encyclopédie'' of Diderot and D'Alembert, and some of the articles in the ''Encyclopédie'' are a direct copy of her work.


Biography


Early life

Émilie du Châtelet was born on 17 December 1706 in
Paris Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, largest city of France. With an estimated population of 2,048,472 residents in January 2025 in an area of more than , Paris is the List of ci ...
, the only daughter amongst six children. Three brothers lived to adulthood: René-Alexandre Le Tonnelier de Breteuil (1698–1720), Charles-Auguste Le Tonnelier de Breteuil (1701–1731) and abbot (1710–1781). Her eldest brother, René-Alexandre, died in 1720, and the next brother, Charles-Auguste, died in 1731. However, her younger brother, Elisabeth-Théodore, lived to a successful old age, becoming an abbot and eventually a bishop. Two other brothers died very young. Du Châtelet also had a half-sister, Michelle, born in 1686, of her father and Anne Bellinzani, an intelligent woman who was interested in astronomy and married to an important Parisian official. Her father was
Louis Nicolas le Tonnelier de Breteuil Louis Nicolas Le Tonnelier, Baron of Breteuil (14 September 1648, in Montpellier – 24 May 1728), baron of Preuilly and Baron de Breteuil, of Breteuil was an officer in the royal household of Louis XIV. He is also notable as the father of the ...
(1648–1728), a member of the lesser nobility. At the time of du Châtelet's birth, her father held the position of the Principal Secretary and Introducer of Ambassadors to King
Louis XIV LouisXIV (Louis-Dieudonné; 5 September 16381 September 1715), also known as Louis the Great () or the Sun King (), was King of France from 1643 until his death in 1715. His verified reign of 72 years and 110 days is the List of longest-reign ...
. He held a weekly ''
salon Salon may refer to: Common meanings * Beauty salon A beauty salon or beauty parlor is an establishment that provides Cosmetics, cosmetic treatments for people. Other variations of this type of business include hair salons, spas, day spas, ...
'' on Thursdays, to which well-respected writers and scientists were invited. Her mother was Gabrielle Anne de Froulay (1670–1740), Baronne de Breteuil and daughter of soldier (1601–1671). Her paternal grandfather was administrator (1609–1685). Her paternal uncle was cleric Claude Le Tonnelier de Breteuil (1644–1698). Among her cousins was nobleman François Victor Le Tonnelier de Breteuil (1686–1743), son of her uncle François Le Tonnelier de Breteuil (1638–1705). Among her nephews was aristocrat, diplomat and statesman Louis Auguste Le Tonnelier de Breteuil (1730–1807).


Early education

Du Châtelet's education has been the subject of much speculation, and nothing is known with certainty. Among their acquaintances was Fontenelle, the perpetual secretary of the French
Académie des Sciences The French Academy of Sciences (, ) is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French Scientific method, scientific research. It was at the forefron ...
. Du Châtelet's father Louis-Nicolas, recognizing her early brilliance, arranged for Fontenelle to visit and talk about astronomy with her when she was 10 years old. Her mother, Gabrielle-Anne de Froulay, had been brought up in a convent, which was at that time the predominant educational institution available to French girls and women. While some sources believe her mother did not approve of her intelligent daughter, or of her husband's encouragement of Émilie's intellectual curiosity, there are also other indications that her mother not only approved of du Châtelet's early education, but actually encouraged her to vigorously question stated fact. In either case, such encouragement would have been seen as unusual for parents of their time and status. When she was small, her father arranged training for her in physical activities such as
fencing Fencing is a combat sport that features sword fighting. It consists of three primary disciplines: Foil (fencing), foil, épée, and Sabre (fencing), sabre (also spelled ''saber''), each with its own blade and set of rules. Most competitive fe ...
and riding, and as she grew older, he brought tutors to the house for her. As a result, by the age of twelve she was fluent in
Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...
,
Italian Italian(s) may refer to: * Anything of, from, or related to the people of Italy over the centuries ** Italians, a Romance ethnic group related to or simply a citizen of the Italian Republic or Italian Kingdom ** Italian language, a Romance languag ...
,
Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...
and German; she was later to publish translations into French of Greek and Latin plays and philosophy. She received education in mathematics, literature, and science. Du Châtelet also liked to dance, was a passable performer on the
harpsichord A harpsichord is a musical instrument played by means of a musical keyboard, keyboard. Depressing a key raises its back end within the instrument, which in turn raises a mechanism with a small plectrum made from quill or plastic that plucks one ...
, sang opera, and was an amateur actress. As a teenager, short of money for books, she used her mathematical skills to devise highly successful strategies for gambling.


Marriage

On 12 June 1725, she married the Marquis Florent-Claude du Chastellet-Lomont (1695–1765).The ''Lomont'' suffix indicates the branch of the ''du Chastellet'' family; another such branch was the ''du Chastellet-Clemont''. Her marriage conferred the title of Marquise du Chastellet.The spelling ''Châtelet'' (replacing the ''s'' by a circumflex over the ''a'') was introduced by
Voltaire François-Marie Arouet (; 21 November 169430 May 1778), known by his ''Pen name, nom de plume'' Voltaire (, ; ), was a French Age of Enlightenment, Enlightenment writer, philosopher (''philosophe''), satirist, and historian. Famous for his wit ...
, and has now become standard. ()
Like many marriages among the nobility, theirs was arranged. As a wedding gift, her husband was made governor of
Semur-en-Auxois Semur-en-Auxois () is a Communes of France, commune of the Côte-d'Or Departments of France, department in eastern France. The politician François Patriat, the engineers Edmé Régnier L'Aîné (1751–1825) and Émile Dorand (1866-1922), and th ...
in
Burgundy Burgundy ( ; ; Burgundian: ''Bregogne'') is a historical territory and former administrative region and province of east-central France. The province was once home to the Dukes of Burgundy from the early 11th until the late 15th century. ...
by his father; the recently married couple moved there at the end of September 1725. Du Châtelet was eighteen at the time, her husband thirty-four. Émilie du Châtelet and the Marquis Florent-Claude du Chastellet-Lomont had three children: Françoise-Gabrielle-Pauline (1726–1754), married in 1743 to Alfonso Carafa, Duca di Montenero (1713–1760), Louis Marie Florent (1727–1793), and Victor-Esprit (1733–1734). Victor-Esprit died as an infant in late summer 1734, likely the last Sunday in August. On 4 September 1749 Émilie du Châtelet gave birth to Stanislas-Adélaïde du Châtelet, daughter of Jean François de Saint-Lambert. She died as a toddler in Lunéville on 6 May 1751.


Resumption of studies

After bearing three children, Émilie, Marquise du Châtelet, considered her marital responsibilities fulfilled and reached an agreement with her husband to live separate lives while still maintaining one household. In 1733, aged 26, du Châtelet resumed her mathematical studies. Initially, she was tutored in algebra and calculus by Moreau de Maupertuis, a member of the Academy of Sciences; although
mathematics Mathematics is a field of study that discovers and organizes methods, Mathematical theory, theories and theorems that are developed and Mathematical proof, proved for the needs of empirical sciences and mathematics itself. There are many ar ...
was not his forte, he had received a solid education from
Johann Bernoulli Johann Bernoulli (also known as Jean in French or John in English; – 1 January 1748) was a Swiss people, Swiss mathematician and was one of the many prominent mathematicians in the Bernoulli family. He is known for his contributions to infin ...
, who also taught
Leonhard Euler Leonhard Euler ( ; ; ; 15 April 170718 September 1783) was a Swiss polymath who was active as a mathematician, physicist, astronomer, logician, geographer, and engineer. He founded the studies of graph theory and topology and made influential ...
. However by 1735 du Châtelet had turned for her mathematical training to
Alexis Clairaut Alexis Claude Clairaut (; ; 13 May 1713 – 17 May 1765) was a French mathematician, astronomer, and geophysicist. He was a prominent Newtonian whose work helped to establish the validity of the principles and results that Isaac Newton, Sir Isaa ...
, a mathematical prodigy known best for Clairaut's equation and Clairaut's theorem. Du Châtelet resourcefully sought some of France's best tutors and scholars to mentor her in mathematics. On one occasion at the Café Gradot, a place where men frequently gathered for intellectual discussion, she was politely ejected when she attempted to join one of her teachers. Undeterred, she returned and entered after having men's clothing made for her.


Relationship with Voltaire

Du Châtelet may have met Voltaire in her childhood at one of her father's '' salons''; Voltaire himself dates their meeting to 1729, when he returned from his exile in London. However, their friendship developed from May 1733 when she re-entered society after the birth of her third child. Du Châtelet invited Voltaire to live at her country house at Cirey in
Haute-Marne Haute-Marne (; English: Upper Marne) is a department in the Grand Est region of Northeastern France. Named after the river Marne, its prefecture is Chaumont. In 2019, it had a population of 172,512.Elements of the Philosophy of Newton ''Elements of the Philosophy of Newton'' () is a book written by the philosopher Voltaire and co-authored by mathematician and physicist Emilie du Chatelet, Émilie du Châtelet in 1738 that helped to popularize the theories and thought of Isaac ...
''. This was through a poem dedicated to her at the beginning of the text and in the preface, where Voltaire praised her study and contributions. The book's chapters on
optics Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of optical instruments, instruments that use or Photodetector, detect it. Optics usually describes t ...
show strong similarities with her own ''Essai sur l'optique''. She was able to contribute further to the campaign by a laudatory review in the '' Journal des savants''. Sharing a passion for science, Voltaire and du Châtelet collaborated scientifically. They set up a laboratory in du Châtelet's home in Lorraine. In a healthy competition, they both entered the 1738 Paris Academy prize contest on the nature of fire, since du Châtelet disagreed with Voltaire's essay. Although neither of them won, both essays received honourable mention and were published. She thus became the first woman to have a scientific paper published by the Academy.


Social life after living with Voltaire

Du Châtelet's relationship with Voltaire caused her to give up most of her social life to become more involved with her study in mathematics with the teacher of Pierre-Louis Moreau de Maupertuis. He introduced the ideas of Isaac Newton to her. Letters written by du Châtelet explain how she felt during the transition from Parisian socialite to rural scholar, from "one life to the next".


Later pregnancy and death

In May 1748, du Châtelet began an affair with the poet Jean François de Saint-Lambert and became pregnant. In a letter to a friend, she confided her fears that she would not survive her pregnancy. On the night of 4 September 1749 she gave birth to a daughter, Stanislas-Adélaïde. Du Châtelet died on 10 September 1749 at Château de Lunéville, from a
pulmonary embolism Pulmonary embolism (PE) is a blockage of an pulmonary artery, artery in the lungs by a substance that has moved from elsewhere in the body through the bloodstream (embolism). Symptoms of a PE may include dyspnea, shortness of breath, chest pain ...
. She was 42. Her infant daughter died 20 months later.


Scientific research and publications


Criticizing Locke and the debate on ''thinking matter''

In her writings, du Châtelet criticized
John Locke John Locke (; 29 August 1632 (Old Style and New Style dates, O.S.) – 28 October 1704 (Old Style and New Style dates, O.S.)) was an English philosopher and physician, widely regarded as one of the most influential of the Enlightenment thi ...
's philosophy. She emphasizes the necessity of the verification of knowledge through experience: "Locke's idea of the possibility of ''thinking matter'' is abstruse". Her critique on Locke originated in her commentary on Bernard de Mandeville's '' The Fable of the Bees''. She resolutely favored universal principles that precondition human knowledge and action, and maintained that this kind of law is innate. Du Châtelet claimed the necessity of a universal presupposition, because if there were no such beginning, all our knowledge is relative. In that way, Du Châtelet rejected Locke's aversion to innate ideas and prior principles. She also reversed Locke's negation of the principle of contradiction, which would constitute the basis of her methodic reflections in the ''Institutions''. On the contrary, she affirmed her arguments in favor of the necessity of prior and universal principles. "Two and two could then make as well 4 as 6 if prior principles did not exist." References by Pierre Louis Moreau de Maupertuis and Julien Offray de La Mettrie to du Châtelet's deliberations on motion, free will, ''thinking matter'', numbers, and the way to conduct
metaphysics Metaphysics is the branch of philosophy that examines the basic structure of reality. It is traditionally seen as the study of mind-independent features of the world, but some theorists view it as an inquiry into the conceptual framework of ...
are a sign of the importance of her reflections. She rebuts the claim to finding truth by using mathematical laws, and argues against Maupertuis.


Fire, heat, and combustion

In 1737, the Royal Academy of Science in Paris (now
French Academy of Sciences The French Academy of Sciences (, ) is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French Scientific method, scientific research. It was at the forefron ...
) announced an essay competition on the question of the nature and propagation of fire, to be awarded the following year.
Voltaire François-Marie Arouet (; 21 November 169430 May 1778), known by his ''Pen name, nom de plume'' Voltaire (, ; ), was a French Age of Enlightenment, Enlightenment writer, philosopher (''philosophe''), satirist, and historian. Famous for his wit ...
, who was then working with Du Châtelet at her estate in Cirey, entered the competition. Eventually, Du Châtelet decided to enter herself, though without informing Voltaire, with whom she had significant theoretical disagreements. While neither of them won the competition, their essays were judged to be of sufficient quality to be published in the collections of the Academy, alongside the winning essays. Her ''Dissertation sur la nature et la propagation du feu'' thus appeared in 1739, the first time the Academy published a work written by a woman. Du Châtelet's essay takes the position that fire is a distinctive type of matter, a common view in the period, and sought to use mechanical theory to understand its properties. For instance, she argued that it is a massless particle, whereas Voltaire had claimed fire had weight. She also speculated that there may be colors in other suns that are not found in the spectrum of sunlight on Earth.


''Institutions de Physique''

Her book ''Institutions de Physique'' ("Lessons in Physics") was published in 1740; it was presented as a review of new ideas in science and philosophy to be studied by her 13-year-old son, but it incorporated and sought to reconcile complex ideas from the leading thinkers of the time. The book and subsequent debate contributed to her becoming a member of the Academy of Sciences of the Institute of Bologna in 1746. Du Châtelet originally preferred anonymity in her role as the author, because she wished to conceal her gender. Ultimately, however, ''Institutions'' was convincing to salon-dwelling intellectuals in spite of the commonplace sexism. ''Institutions'' discussed, refuted, and synthesized many ideas of prominent mathematicians and physicists of the time. In particular, the text is famous for discussing ideas that originated with G. W. Leibniz and Christian Wolff, and for using the principle of sufficient reason often associated with their philosophical work. This main work is equally famous for providing a detailed discussion and evaluation of ideas that originated with Isaac Newton and his followers. That combination is more remarkable than it might seem now, since the ideas of Leibniz and Newton were regarded as fundamentally opposed to one another by most of the major philosophical figures of the eighteenth century. In chapter I, du Châtelet included a description of her rules of reasoning, based largely on Descartes’s principle of contradiction and Leibniz’s principle of sufficient reason. In chapter II, she applied these rules of reasoning to metaphysics, discussing God, space, time, and matter. In chapters III through VI, du Châtelet continued to discuss the role of God and his relationship to his creation. In chapter VII, she broke down the concept of matter into three parts: the macroscopic substance available to sensory perception, the atoms composing that macroscopic material, and an even smaller constituent unit similarly imperceptible to human senses. However, she carefully added that there was no way to know how many levels truly existed. The remainder of ''Institutions'' considered more metaphysics and classical mechanics. Du Châtelet discussed the concepts of space and time in a manner more consistent with modern relativity than her contemporaries. She described both space and time in the abstract, as representations of the relationships between coexistent bodies rather than physical substances. This included an acknowledgement that "absolute" place is an idealization and that "relative" place is the only real, measurable quantity. Du Châtelet also presented a thorough explanation of Newton’s laws of motion and their function on earth.


Forces Vives

In 1741, du Châtelet published a book entitled ''Réponse de Madame la Marquise du Chastelet, a la lettre que M. de Mairan''. D'Ortous de Mairan, secretary of the Academy of Sciences, had published a set of arguments addressed to her regarding the appropriate mathematical expression for ''forces vives'' ("living forces"). Du Châtelet presented a point-by-point rebuttal of de Mairan's arguments, causing him to withdraw from the controversy.
Immanuel Kant Immanuel Kant (born Emanuel Kant; 22 April 1724 – 12 February 1804) was a German Philosophy, philosopher and one of the central Age of Enlightenment, Enlightenment thinkers. Born in Königsberg, Kant's comprehensive and systematic works ...
's first publication in 1747, '
Thoughts on the True Estimation of Living Forces ''Thoughts on the True Estimation of Living Forces'' () is Immanuel Kant's first published work, published in 1749. It is the first of Kant's works on natural philosophy. The ''True Estimation'' is divided into a preface and three chapters. Chap ...
' (''Gedanken zur wahren Schätzung der lebendigen Kräfte''), focused on du Châtelet's pamphlet rebutting the arguments of the secretary of the French Academy of Sciences, Mairan. Kant's opponent,
Johann Augustus Eberhard Johann Augustus Eberhard (August 31, 1739January 6, 1809) was a German theologian and "popular philosopher". Life and career Eberhard was born at Halberstadt in the Principality of Halberstadt, where his father was a school teacher and the singi ...
, accused Kant of taking ideas from du Châtelet. In his ''
Observations on the Feeling of the Beautiful and Sublime ''Observations on the Feeling of the Beautiful and Sublime'' () is a 1764 book by Immanuel Kant. The first complete translation into English was published in 1799. The second, by John T. Goldthwait, was published in 1960 by the University of Ca ...
'', Kant wrote
ad hominem , short for , refers to several types of arguments that are usually fallacious. Often currently this term refers to a rhetorical strategy where the speaker attacks the character, motive, or some other attribute of the person making an argument ...
and sexist critiques of learned women of the time, including Mme Du Châtelet, rather than writing about their work. Kant stated: "A woman who has a head full of Greek, like Mme. Dacier, or who conducts disputations about mechanics, like the Marquise du Châtelet might as well also wear a beard; for that might perhaps better express the mien of depth for which they strive."


Advocacy of kinetic energy

Although in the early eighteenth century the concepts of force and
momentum In Newtonian mechanics, momentum (: momenta or momentums; more specifically linear momentum or translational momentum) is the product of the mass and velocity of an object. It is a vector quantity, possessing a magnitude and a direction. ...
had been long understood, the idea of energy as being transferable between different systems was still in its infancy, and would not be fully resolved until the nineteenth century. It is now accepted that the total mechanical momentum of a system is conserved and that none is lost to friction. Simply put, there is no 'momentum friction', and momentum cannot transfer between different forms, and particularly, there is no 'potential momentum'. In the twentieth century,
Emmy Noether Amalie Emmy Noether (23 March 1882 – 14 April 1935) was a German mathematician who made many important contributions to abstract algebra. She also proved Noether's theorem, Noether's first and Noether's second theorem, second theorems, which ...
proved this to be true for all problems where the initial state is
symmetric Symmetry () in everyday life refers to a sense of harmonious and beautiful proportion and balance. In mathematics, the term has a more precise definition and is usually used to refer to an object that is invariant under some transformations ...
in generalized coordinates. E.g., mechanical energy, either kinetic or potential, may be lost to another form, but the total is conserved in time. Du Châtelet's contribution was the hypothesis of the conservation of total energy, as distinct from momentum. In doing so, she became the first to elucidate the concept of energy as such, and to quantify its relationship to mass and velocity based on her own empirical studies. Inspired by the theories of
Gottfried Leibniz Gottfried Wilhelm Leibniz (or Leibnitz; – 14 November 1716) was a German polymath active as a mathematician, philosopher, scientist and diplomat who is credited, alongside Isaac Newton, Sir Isaac Newton, with the creation of calculus in ad ...
, she repeated and publicized an experiment originally devised by
Willem 's Gravesande Willem Jacob 's Gravesande (26 September 1688 – 28 February 1742) was a Dutch mathematician and natural philosopher, chiefly remembered for developing experimental demonstrations of the laws of classical mechanics and the first experimental m ...
in which heavy balls were dropped from different heights into a sheet of soft clay. Each ball's
kinetic energy In physics, the kinetic energy of an object is the form of energy that it possesses due to its motion. In classical mechanics, the kinetic energy of a non-rotating object of mass ''m'' traveling at a speed ''v'' is \fracmv^2.Resnick, Rober ...
– as indicated by the quantity of material displaced – was shown to be proportional to the square of the
velocity Velocity is a measurement of speed in a certain direction of motion. It is a fundamental concept in kinematics, the branch of classical mechanics that describes the motion of physical objects. Velocity is a vector (geometry), vector Physical q ...
: She showed that if two balls were identical except for their mass, they would make the same size indentation in the clay if the quantity mv^2 (then called ''
vis viva ''Vis viva'' (from the Latin for "living force") is a historical term used to describe a quantity similar to kinetic energy in an early formulation of the principle of conservation of energy. Overview Proposed by Gottfried Leibniz over the period ...
'') were the same for each ball. Newton's work assumed the exact conservation of only mechanical momentum. A broad range of mechanical problems in physics are soluble only if energy conservation is included. The collision and scattering of two point masses is one example.
Leonhard Euler Leonhard Euler ( ; ; ; 15 April 170718 September 1783) was a Swiss polymath who was active as a mathematician, physicist, astronomer, logician, geographer, and engineer. He founded the studies of graph theory and topology and made influential ...
and
Joseph-Louis Lagrange Joseph-Louis Lagrange (born Giuseppe Luigi LagrangiaPhilosophiae Naturalis Principia Mathematica Philosophy ('love of wisdom' in Ancient Greek) is a systematic study of general and fundamental questions concerning topics like existence, reason, knowledge, value, mind, and language. It is a rational and critical inquiry that reflects on ...
'' (often referred to as simply the ''Principia''), including her derivation of the notion of
conservation of energy The law of conservation of energy states that the total energy of an isolated system remains constant; it is said to be Conservation law, ''conserved'' over time. In the case of a Closed system#In thermodynamics, closed system, the principle s ...
from its principles of mechanics. Despite modern misconceptions, Newton's work on his ''Principia'' was not perfect. Du Châtelet took on the task of not only translating his work from Latin to French, but adding important information to it as well. Her commentary was as essential to her contemporaries as her spreading of Newton's ideas. Du Châtelet's commentary was very extensive, comprising almost two-thirds of volume II of her edition. To undertake a formidable project such as this, du Châtelet prepared to translate the ''Principia'' by continuing her studies in
analytic geometry In mathematics, analytic geometry, also known as coordinate geometry or Cartesian geometry, is the study of geometry using a coordinate system. This contrasts with synthetic geometry. Analytic geometry is used in physics and engineering, and als ...
, mastering
calculus Calculus is the mathematics, mathematical study of continuous change, in the same way that geometry is the study of shape, and algebra is the study of generalizations of arithmetic operations. Originally called infinitesimal calculus or "the ...
, and reading important works in experimental physics. It was her rigorous preparation that allowed her to add a lot more accurate information to her commentary, both from herself and other scientists she studied or worked with. She was one of only 20 or so people in the 1700s who could understand such advanced math and apply the knowledge to other works. This helped du Châtelet greatly, not only with her work on the ''Principia'' but also in her other important works like the ''Institutions de Physique''. Du Châtelet made very important corrections in her translation that helped support Newton's theories about the universe. Newton, based on the theory of fluids, suggested that gravitational attraction would cause the poles of the earth to flatten, thus causing the earth to bulge outwards at the
equator The equator is the circle of latitude that divides Earth into the Northern Hemisphere, Northern and Southern Hemisphere, Southern Hemispheres of Earth, hemispheres. It is an imaginary line located at 0 degrees latitude, about in circumferen ...
. In Clairaut's ''Memoire'', which confirmed Newton's hypothesis about the shape of the Earth and gave more accurate approximations, Clairaut discovered a way to determine the shape of the other planets in the
Solar System The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Sola ...
. Du Châtelet used Clairaut's proposal that the planets had different densities in her commentary to correct Newton's belief that the Earth and the other planets were made of
homogeneous Homogeneity and heterogeneity are concepts relating to the uniformity of a substance, process or image. A homogeneous feature is uniform in composition or character (i.e., color, shape, size, weight, height, distribution, texture, language, i ...
substances. Du Châtelet used the work of
Daniel Bernoulli Daniel Bernoulli ( ; ; – 27 March 1782) was a Swiss people, Swiss-France, French mathematician and physicist and was one of the many prominent mathematicians in the Bernoulli family from Basel. He is particularly remembered for his applicati ...
, a Swiss mathematician and physicist, to further explain Newton's theory of the
tide Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another. Tide tables ...
s. This proof depended upon the
three-body problem In physics, specifically classical mechanics, the three-body problem is to take the initial positions and velocities (or momenta) of three point masses orbiting each other in space and then calculate their subsequent trajectories using Newton' ...
which still confounded even the best mathematicians in 18th century Europe. Using Clairaut's hypothesis about the differing of the planets' densities, Bernoulli theorized that the moon was 70 times denser than Newton had believed. Du Châtelet used this discovery in her commentary of the ''Principia'', further supporting Newton's theory about the
law of gravitation Newton's law of universal gravitation describes gravity as a force by stating that every particle attracts every other particle in the universe with a force that is proportional to the product of their masses and inversely proportional to the ...
. Published ten years after her death, today du Châtelet's translation of the ''Principia'' is still the standard translation of the work into French, and remains the only complete rendition in that language. Her translation was so important that it was the only one in any language used by Newtonian expert I. Bernard Cohen to write his own English version of Newton's ''Principia''. Du Châtelet not only used the works of other great scientists to revise Newton's work, but she added her own thoughts and ideas as a scientist in her own right. Her contributions in the French translation made Newton and his ideas look even better in the
scientific community The scientific community is a diverse network of interacting scientists. It includes many "working group, sub-communities" working on particular scientific fields, and within particular institutions; interdisciplinary and cross-institutional acti ...
and around the world, and recognition for this is owed to du Châtelet. This enormous project, along with her ''Foundations of Physics'', proved du Châtelet's abilities as a great mathematician. Her translation and commentary of the ''Principia'' contributed to the completion of the
scientific revolution The Scientific Revolution was a series of events that marked the emergence of History of science, modern science during the early modern period, when developments in History of mathematics#Mathematics during the Scientific Revolution, mathemati ...
in France and to its acceptance in Europe.


Possible Influence on

Immanuel Kant Immanuel Kant (born Emanuel Kant; 22 April 1724 – 12 February 1804) was a German Philosophy, philosopher and one of the central Age of Enlightenment, Enlightenment thinkers. Born in Königsberg, Kant's comprehensive and systematic works ...

Kant mostly engaged with Georg Friedrich Meier’s Excerpts from the Doctrine of Reason (1752) in his logic lectures. It is highly plausible that Du Châtelet’s presence was recognized by contemporaries such as Baumgarten, which alludes to a connection that might have broader implications for Kant’s knowledge of Du Châtelet. Notably, Meier’s involvement in the publication of Christine Ziegler (later Unzer)’s work Grundriss einer Weltweisheit für das Frauenzimmer (A Sketch of a World Wisdom for Women) suggests a potential linkage to Du Châtelet’s philosophical ideas. Hence, Du Châtelet’s name held certain significance within Meier’s sphere of influence. The immediate translation of the Institutions into German following its release also implies its likely role in paving the philosophical path for Kant’s later endeavors.


Illusions and happiness

In '' Discours sur le bonheur'', Émilie Du Châtelet argues that illusions are an instrument for happiness. To be happy, “one must have freed oneself of prejudice, one must be virtuous, healthy, have tastes and passions, and be susceptible to illusions...”. She mentions many things one needs for happiness, but emphasizes the necessity of illusions and that one should not dismiss all illusions. One should not abandon all illusions because they can bestow positivity and hope, which can ameliorate one's well-being. But Du Châtelet also warns against trusting all illusions, because many illusions are harmful to oneself. They may cause negativity through a false reality, which can cause disappointment or even limit one’s abilities. This lack of self-awareness from so many illusions may cause one to be self-deceived. She suggests a balance of trusting and rejecting illusions for happiness, so as not to become self-deceived. In ''Foundation of Physics'', Émilie Du Châtelet discusses avoiding error by applying two principles – the
principle of contradiction In logic, the law of noncontradiction (LNC; also known as the law of contradiction, principle of non-contradiction (PNC), or the principle of contradiction) states that for any given proposition, the proposition and its negation cannot both be s ...
and the
principle of sufficient reason The principle of sufficient reason states that everything must have a Reason (argument), reason or a cause. The principle was articulated and made prominent by Gottfried Wilhelm Leibniz, with many antecedents, and was further used and developed by ...
. Du Châtelet presumed that all knowledge is developed from more fundamental knowledge that relies on infallible knowledge. She states that this infallible fundamental knowledge is most reliable because it is self-explanatory and exists with a small number of conclusions. Her logic and principles are used for an arguably less flawed understanding of
physics Physics is the scientific study of matter, its Elementary particle, fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge whi ...
,
metaphysics Metaphysics is the branch of philosophy that examines the basic structure of reality. It is traditionally seen as the study of mind-independent features of the world, but some theorists view it as an inquiry into the conceptual framework of ...
, and
morals Morality () is the categorization of intentions, decisions and actions into those that are ''proper'', or ''right'', and those that are ''improper'', or ''wrong''. Morality can be a body of standards or principles derived from a code of conduc ...
. The principle of contradiction essentially claims that the thing implying a contradiction is impossible. So, if one does not use the principle of contradiction, one will have errors including the failure to reject a contradiction-causing element. To get from the possible or impossible to the actual or real, the principle of sufficient reason was revised by Du Châtelet from Leibniz's concept and integrated into science. The principle of sufficient reason suggests that every true thing has a reason for being so, and things without a reason do not exist. In essence, every effect has a cause, so the element in question must have a reasonable cause to be so. In application, Émilie Du Châtelet proposed that being happy and immoral are
mutually exclusive In logic and probability theory, two events (or propositions) are mutually exclusive or disjoint if they cannot both occur at the same time. A clear example is the set of outcomes of a single coin toss, which can result in either heads or tails ...
. According to Du Châtelet, this principle is embedded within the hearts of all individuals, and even wicked individuals have an undeniable consciousness of this contradiction that is grueling. It suggests one cannot be living a happy life while living immorally. So, her suggested happiness requires illusions with a virtuous life. These illusions are naturally given like passions and tastes, and cannot be created. Du Châtelet recommended we maintain the illusions we receive and work to not dismantle the trustworthy illusions, because we cannot get them back. In other words, true happiness is a blending of illusions and morality. If one merely attempts to be moral, one will not obtain the happiness one deeply seeks. If one just strives for the illusions, one will not get the happiness that is genuinely desired. One needs to endeavor in both illusions and happiness to get the sincerest happiness.


Other contributions


Development of financial derivatives

Du Châtelet lost the considerable sum for the time of 84,000 francs—some of it borrowed—in one evening at the table at the Court of Fontainebleau, to card cheats. To raise the money to pay back her debts, she devised an ingenious financing arrangement similar to modern derivatives, whereby she paid tax collectors a fairly low sum for the right to their future earnings (they were allowed to keep a portion of the taxes they collected for the King), and promised to pay the court gamblers part of these future earnings.


Biblical scholarship

Du Châtelet wrote a critical analysis of the entire Bible. A synthesis of her remarks on the
Book of Genesis The Book of Genesis (from Greek language, Greek ; ; ) is the first book of the Hebrew Bible and the Christian Old Testament. Its Hebrew name is the same as its incipit, first word, (In the beginning (phrase), 'In the beginning'). Genesis purpor ...
was published in English in 1967 by Ira O. Wade of Princeton in his book ''Voltaire and Madame du Châtelet: An Essay on Intellectual Activity at Cirey'' and a book of her complete notes was published in 2011, in the original French, edited and annotated by Bertram Eugene Schwarzbach.


Translation of the ''Fable of the Bees'', and other works

Du Châtelet translated '' The Fable of the Bees'' in a free adaptation. She also wrote works on optics, rational linguistics, and the nature of free will.


Support of women's education

In her first independent work, the preface to her translation of the ''Fable of the Bees'', du Châtelet argued strongly for
women's education Female education is a catch-all term for a complex set of issues and debates surrounding education (primary education, secondary education, tertiary education, and health education in particular) for girls and women. It is frequently called girls ...
, particularly a strong secondary education as was available for young men in the French '' collèges''. By denying women a good education, she argued, society prevents women from becoming eminent in the arts and sciences.


Legacy

Du Châtelet made a crucial scientific contribution in making Newton's historic work more accessible in a timely, accurate and insightful French translation, augmented by her own original concept of energy conservation. A main-belt minor planet and a crater on Venus have been named in her honor, and she is the subject of three plays: ''Legacy of Light'' by Karen Zacarías; ''Émilie: La Marquise Du Châtelet Defends Her Life Tonight'' by Lauren Gunderson and ''Urania: the Life of Émilie du Châtelet'' by Jyl Bonaguro. The opera ''
Émilie Émilie () is a French female given name. It is the feminine form of the male name Émile. People named Émilie and Emilie include: * Émilie Ambre (1849–1898), French opera singer * Emilie Autumn (born 1979), American singer-songwriter, poet ...
'' by Kaija Saariaho is about the last moments of her life. Du Châtelet is often represented in portraits with mathematical iconography, such as holding a pair of
dividers Calipers or callipers are an instrument used to Measurement, measure the linear dimensions of an object or hole; namely, the length, width, thickness, diameter or depth of an object or hole. The word "caliper" comes from a corrupt form of calibe ...
or a page of geometrical calculations. In the early nineteenth century, a French pamphlet of celebrated women (''Femmes célèbres'') introduced a possibly apocryphal story of her childhood. According to this story, a servant fashioned a doll for her by dressing up wooden dividers as a doll; however, du Châtelet undressed the dividers, and intuiting their original purpose, drew a circle with them. The Institut Émilie du Châtelet, which was founded in France in 2006, supports "the development and diffusion of research on women, sex, and gender". Since 2016, the French Society of Physics (la Société Française de Physique) has awarded the Émilie Du Châtelet Prize to a physicist or team of researchers for excellence in Physics.
Duke University Duke University is a Private university, private research university in Durham, North Carolina, United States. Founded by Methodists and Quakers in the present-day city of Trinity, North Carolina, Trinity in 1838, the school moved to Durham in 1 ...
also presents an annual Du Châtelet Prize in Philosophy of Physics "for previously unpublished work in philosophy of physics by a graduate student or junior scholar". On December 17, 2021,
Google Doodle Google Doodle is a special, temporary alteration of the logo on Google's homepages intended to commemorate holidays, events, achievements, and historical figures. The first Google Doodle honored the 1998 edition of the long-running annual Bu ...
honored du Châtelet. Émilie du Châtelet was portrayed by the actress
Hélène de Fougerolles Hélène Christine Marie Rigoine de Fougerolles (; born 25 February 1973) is a French people, French actress who was twice nominated for the César Award for Most Promising Actress (known as the French Academy Awards, Oscar) for Arthur Joffé's L ...
in the docudrama ''Einstein's Big Idea''.


Works

Scientific * ''Dissertation sur la nature et la propagation du feu'' (1st edition, 1739; 2nd edition, 1744) * ''Institutions de physique'' (1st edition, 1740; 2nd edition, 1742) * ''Principes mathématiques de la philosophie naturelle par feue Madame la Marquise du Châtelet'' (1st edition, 1756; 2nd edition, 1759) Other * ''Examen de la Genèse'' * ''Examen des Livres du Nouveau Testament'' * ''Discours sur le bonheur''


See also

*
Timeline of women in science This is a timeline of women in science, spanning from ancient history up to the 21st century. While the timeline primarily focuses on women involved with natural sciences such as astronomy, biology, chemistry and physics, it also includes women f ...


Explanatory notes


Notes


References

* Team, Project Vox.
Du Châtelet (1706–1749)
. ''Project Vox''. Retrieved 2023-10-20. * * * * *


Further reading

* * * * *


External links


Émilie Du Châtelet (1706-1749)
''Project Vox'' * Zinsser, Judith. 2007
Mentors, the marquise Du Châtelet and historical memory
*

Agnes Scott College Agnes Scott College is a Private university, private Women's Colleges in the Southern United States, women's Liberal arts colleges in the United States, liberal arts college in Decatur, Georgia. The college enrolls approximately 1,000 undergra ...

Correspondence between Frederick the Great and the Marquise du Châtelet
Digital edition of Trier University Library (French and German text) * {{DEFAULTSORT:Chatelet, Emilie Du 1706 births 1749 deaths 18th-century French mathematicians 18th-century French philosophers 18th-century French women scientists 18th-century French women writers 18th-century French writers Scientists from Paris French marchionesses Contributors to the Encyclopédie (1751–1772) French physicists French women scientists Women encyclopedists French women mathematicians French women physicists Deaths in childbirth Deaths from pulmonary embolism 18th-century French translators French women philosophers Latin–French translators 18th-century French scientists Muses (persons)