Jean le Rond d'Alembert

Jean Le Rond d'Alembert (November 16, 1717 - October 29, 1783) was a French mathematician, mechanician, physicist and philosopher. He was also one of the editors of "L'Encyclopédie", an early French encyclopedia. D'Alembert's method for the wave equation is named after him.

Childhood

Born on November 16, 1717 in Paris, d'Alembert was the illegitimate child of the writer Claudine Guérin de Tencin and the chevalier Louis-Camus Destouches (and artillery officer). Destouches was abroad at the time of d'Alembert's birth, and a couple of days after birth his mother left him on the steps of the Saint-Jean-le-Rond de Paris church. According to custom he is named after the protecting saint of the church. d'Alembert is placed in the home for found children, but is quickly adopted by the wife of a glazier. Destouches secretly pays for the education of Jean le Rond because he does not want his parentage officially recognised.

Studies

D'Alembert first visited a private school. The chevalier Destouches left d'Alembert an annuity of 1'200 livres at his death in 1726. Due to the influence of the Destouches family, at the age of twelve d'Alembert entered the Quatre-Nations jansenist collège (the institution was also known under the name Mazarin). Here he studied philosophy, law, and art, receiving bachelier in 1735. In his later life d'Alembert scorned the Cartesian principles he had been taught by the Jansenists: "physical premotion, innate ideas and the vortices". The Jansenists steered d'Alembert toward an ecclesiastical career, attempting to deter him from pursuits such as poetry and mathematics. Theology was, however, "rather unsubstantial fodder" to d'Alembert. He entered into Law School for two years, and was nominated avocat in 1738. He was also interested in medicine and mathematics. Jean le Rond was first registered under the name Daremberg, but later changed it to d'Alembert. In July of 1739 he made his first contribution to the field of mathematics, pointing out the errors he had detected in l'analyse démontrée (published 1708 by Charles René Reynaud) in a communication addressed to the Académie des Sciences. At the time l'analyse démontrée was a standard work, which d'Alembert himself had used to study the foundations of mathematics.

In 1740 he submited his second scientific work from the field of fluid mechanics Memoire sur le refraction des corps solides, which was recognized by Clairaut. In this work d'Alembert theoretically explained refraction.

D'Alembert died in Paris.

L'Encyclopédie

Literature