French physicist who formulated the least action principle, which states that nature chooses the most economical path for moving bodies, light rays, etc. The principle was mathematically refined later by William Rowan Hamilton. Maupertuis claimed that the principle provided a metaphysical proof of the existence of God. Maupertuis also investigated polydactylism and the transmission of abnormal characteristics. His interest in the subject was founded in embryology, however, rather than heredity. He was the driving force behind expeditions to Lapland, near the North Pole, and Peru, on the equator, to measure the difference in the Earth's radius. He accompanied the team (which included Clairaut) to Lapland and, in 1747, the two groups proved Newton's prediction that the earth was an oblate spheroid to be correct, while Descartes's theory which predicted an ovate Earth to be wrong.

Additional biographies: MacTutor (St. Andrews), Bonn