Émilie du Châtelet
Gabrielle Émilie Le Tonnelier de Breteuil, Marquise du Châtelet was a French mathematician and physicist.
Her most recognized achievement is her philosophical magnum opus, Institutions de Physique. She then revised the text substantially for a second edition with the slightly modified title Institutions physiques. 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's Philosophiæ Naturalis Principia Mathematica. The text, published posthumously in 1756, is still considered the standard French translation to this day.
Du Châtelet participated in the famous vis viva 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, the Encyclopédie of Denis Diderot and Jean le Rond d'Alembert, first published shortly after du Châtelet's death.
She is also known as the intellectual collaborator with and romantic partner of Voltaire. 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.Because of her well-known collaboration and romantic involvement with Voltaire 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 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 and Leonhard Euler, early developers of calculus. She was also tutored by Bernoulli's prodigy students, Pierre Louis Moreau de Maupertuis and Alexis Claude Clairaut. 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 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, the only daughter amongst six children. Three brothers lived to adulthood: René-Alexandre Le Tonnelier de Breteuil, Charles-Auguste Le Tonnelier de Breteuil and abbot . 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, 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. He held a weekly salon on Thursdays, to which well-respected writers and scientists were invited. Her mother was Gabrielle Anne de Froulay, Baronne de Breteuil and daughter of soldier . Her paternal grandfather was administrator . Her paternal uncle was cleric Claude Le Tonnelier de Breteuil. Among her cousins was nobleman François Victor Le Tonnelier de Breteuil, son of her uncle François Le Tonnelier de Breteuil. Among her nephews was aristocrat, diplomat and statesman Louis Auguste Le Tonnelier de Breteuil.
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. 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 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, Italian, Greek 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, 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. Her marriage conferred the title of Marquise du Chastellet. Like many marriages among the nobility, theirs was arranged. As a wedding gift, her husband was made governor of Semur-en-Auxois in Burgundy 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, married in 1743 to Alfonso Carafa, Duca di Montenero, Louis Marie Florent, and Victor-Esprit. 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 was not his forte, he had received a solid education from Johann Bernoulli, who also taught Leonhard Euler. However by 1735 du Châtelet had turned for her mathematical training to Alexis Clairaut, 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, northeastern France, and he became her long-time companion. There she studied physics and mathematics, and published scientific articles and translations. To judge from Voltaire's letters to friends and their commentaries on each other's work, they lived together with great mutual liking and respect. As a literary rather than scientific person, Voltaire implicitly acknowledged her contributions to his 1738 Elements of the Philosophy of Newton. 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 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.