Émilie du Châtelet, full name Gabrielle Émilie Le Tonnelier de Breteuil, Marquise du Châtelet, was born on the seventeenth of December, 1706, in Paris. She was an Enlightenment-age physicist, mathematician and author.
Châtelet was one of six children, and the only girl among them. Only three of her brothers lived to adulthood, as was unfortunately common at the time, and two more of her brothers died in young adulthood.
Only one of her brothers lived to old age, Elisabeth-Theodore, who became a bishop. Châtelet also had an illegitimate half-sister, Michelle.
Châtelet was born into a high-class family. Her father, Louis Nicolas le Tonnelier de Breteuil, was of minor nobility and was the Principal Secretary and Introducer of Ambassadors for King Louis XIV.
Châtelet was soon introduced to her father’s acquaintance Bernard le Bovier de Fontenelle, the secretary of the Academie des Sciences. Her father arranged for Fontenelle to tutor Châtelet starting at age ten.
By age twelve, Châtelet was fluent in German, Latin, Italian and Greek, as well as her native French. Her father encouraged her to learn riding and fencing, and brought more tutors for her.
Châtelet’s mother’s opinion on this is unclear, as by some accounts she did not approve of her educated daughter, and by others she actively encouraged Châtelet in her critical thinking skills and to learn as much as she could.
However, after Châtelet began publishing translations of Greek and Latin philosophy, her mother attempted to have her sent to a convent. Châtelet’s father prevented it from happening.
While still a teenager and short on money, Châtelet applied her mathematical skill to gambling, and was quite successful.
Châtelet married the Marquis Florent-Claude du Chastellet-Lomont on June 12, 1725. This made her the Marquise du Chastellet (later standardized to Châtelet). She was eighteen at the time, and her husband was thirty. They had three children together, though two died young.
In 1729, Châtelet met the philosopher and writer Voltaire, and they quickly became friends. She invited him to live at Cirey-sur-Blaise, her country house in northeastern France.
There is little evidence that they were ever lovers, and they worked alongside each other, Châtelet publishing numerous scientific articles and various translations during that time.
After beginning an affair with the poet Jean Francois de Saint-Lambert in may of 1748, Châtelet became pregnant but suspected that not all was well. She sent a letter to a friend, fearing that she would not survive it, and a week after giving birth to a daughter died of a pulmonary embolism. Her daughter lived only for a year and a half.