Jean le Rond d'Alembert and Adoption

Jean-Baptiste le Rond d'Alembert, pastel by Maurice Quentin de La Tour



French philosopher, mathematician, and encyclopedist

d'Alembert was a foundling, discovered near the church of St. Jean-le-Rond in Paris (hence his name), but he was in fact the son of Madame de Tencin and General Destouches-Canon. His father soon reclaimed him, placing him for fostering with a glazier's family named Rousseau, and he continued to care about him and was responsible for him receiving an excellent education, although he never publicly revealed his identity. d'Alembert refused to be reconciled with his mother when she made overtures to him.

He became a brilliant mathematician and a member of the French Academy of Sciences. He was also a philosopher and a member of the circle surrounding Diderot. He helped write the great Encyclopédie, one of the crowning achievements of the French enlightenment. His published works run to 18 volumes. He also gave much of his income to charity.


Dever, Maria, and Dever, Aileen. Relative Origins: Famous Foster and Adopted People. (Portland: National Book Company, 1992) Microsoft Encarta 98 Encyclopedia, 1993-97 Encyclopedia of Philosophy. 8 vols. (New York: Macmillan, 1967) Oxford Dictionary of the Christian Church, edited by F.L. Cross. (London: Oxford University Press, 1957) "d'Alembert, Jean-le-Rond, 1717-1783." [Includes portrait]. Available at: "Jean le Ronde d'Alembert." [Includes portrait]. Available at:'Alembert.html