A French mathematician and astronomer who, at the age of 24 was named "the Newton of France" for certain of his discoveries. In the years 1799-1825 his great work, the Mecanique celeste, which, as its author stated, "offers a complete solution of the great mechanical problem presented by the solar system," appeared in 5 volumes, published in Paris. In his second great work, the Exposition du systeme du monde, Paris, 1796, appeared his statement of his famous "nebular hypothesis," the origins of which he seems to attribute to Buffon, apparently unaware that Immanuel Kant had at least partially anticipated him in his Allgemeine Naturgeschichte, General History of Nature, published in 1755.