Pierre Simon (pjɛr simɔ̃), Marquis de Laplace. 1749–1827, French mathematician, physicist, and astronomer. He formulated the nebular hypothesis (1796). He also developed the theory of probability
Laplace in American English
(laˈplas)
Marquis Pierre Siˈmon de (pjɛʀsiˈmɔ̃̃ də) 1749-1827; Fr. mathematician & astronomer