French mathematician, philosopher, and a leading figure of the Enlightenment.

Studied theology and mathematics at the Jansenist Collège des Quatre-Nations. Admitted to the Académie des Sciences in Paris (1741).

Outlined his principle of mechanics, known as the principe de d’Alembert, in his Traité de dynamique (1743). Won the prize of the Academy of Berlin for his Réflexions sur la cause générale des vents (1746).

Published important works on partial differential equations, and the motions of fluids and vibrating strings.

Associated with Diderot as one of the editors of the twenty-eight volume Encyclopédie, for which he wrote the Discours préliminaire (1751), as well as numerous other scientific and literary articles.

Published many of his philosophical works in the five volume Mélanges de littérature et de philosophie (1753-67).

Elected to the Académie française (1754); named its Perpetual Secretary (1772).

Born in Paris.