Bernard Lamy

Bernard Lamy (1640 to 1715) was a French priest of the Oratory, born in Le Mans and active in Cartesian teaching at Saumur, Angers, Grenoble and finally Rouen. He was both a mathematician and a prolific author on rhetoric, biblical scholarship and perspective. His Traite de mecanique of 1679 states the parallelogram of forces, a result Pierre Varignon reached independently at about the same time, and he also wrote on geometry, algebra and the geometry of painting. His anonymous treatise on the art of speaking of 1675 became an influential rhetoric handbook, and his enthusiasm for Descartes brought him a royal decree against his lectures and a period of exile in 1676. He is remembered in mathematics chiefly for his early statement of the composition of forces.