Description
Jean le Rond d’Alembert (1717-83) was the illegitimate son of Madame de Tencin and General Destouches-Canon and was named after the St Jean
le Rond church on the steps of which he was found.

D’Alembert always refused to be reconciled with his mother but his father reclaimed him and placed him in fostering with a glazier’s family named Rousseau. He provided for his education whilst never publicly revealing his identity.

After graduating from the Collège des Quatres Nations, d’Alembert went through studies of law and medicine. His interests, however, always lay predominantly with maths and in May 1741 he was admitted to the Paris Academy of Science on the basis of his work on Reyneau, mechanics and integral calculus.

His work was distinguished. In 1746 he edited Encyclopédie with Diderot and was a pioneer in the study of partial differential equations and their use in physics. He was one of the first to understand the importance of functions and defined the derivative of a function as the limit of a quotient of increments. In addition, he solved the procession of equinoxes and was the first to find and solve the wave equation, whilst in mechanics he created d’Alembert’s principle which permits the reduction of a problem in dynamics to one in statics.

His achievements were, however, frequently tainted. In 1747 he won the prize of the Prussian Academy but his work was criticised for being mathematically sound but based on poor physical evidence, a flaw running through many of his ideas.

His personality also had a major effect on the way his scientific work developed. There was a permanent rivalry between d’Alembert and Clairaut stemming back from their time at the Paris Academy of Science, and a previously good relationship between d’Alembert and Euler turned sour partly over issues at the Berlin Academy. Relations were made worse because d’Alembert also felt that Euler was stealing his ideas without giving him enough credit. In reality d’Alembert’s work was usually so muddled that Euler could not follow it and had to start from scratch.

In the later part of his life, d’Alembert turned more towards literature and philosophy. On 28th November 1754 he was elected to the French Academy but after a bout of illness, d’Alembert claimed from 1765 that he could no longer concentrate on mathematics. He suffered bad health for many years and died because of a bladder illness. As a known unbeliever, he was buried in a common, unmarked grave.

14/05/2003
Created by: Tudor. Rebecca on 14/05/2003