Lagrange, Joseph (1736-1813)
French mathematician and mathematical physicist who was the greatest mathematician of the eighteenth century. His work Mécanique Analytique (Analytical Mechanics) (1788) was a mathematical masterpiece. It contained clear, symmetrical notation and covered almost every area of pure mathematics.
It was the first book of mechanics Eric Weisstein's World of Physics published without the use of a single diagram. Lagrange succeeded Euler as the director of the Berlin Academy.
Lagrange developed the calculus of variations Eric Weisstein's World of Math which was later expanded by Weierstraß.
Lagrange also established the theory of differential equations, Eric Weisstein's World of Math and provided many new solutions and theorems in number theory, Eric Weisstein's World of Math including Wilson's theorem.
Eric Weisstein's World of Math Lagrange's classic Théorie des fonctions analytiques laid some of the foundations of group theory, Eric Weisstein's World of Math anticipating Galois.
Lagrange also invented the method of solvingdifferential equations Eric Weisstein's World of Math known as variation of parameters.
Eric Weisstein's World of Math Lagrange commented that "I have always observed that the pretensions of all people are in exact inverse ratio to their merits; this is one of the axioms of morals" (Bell 1937, p. 160).