1608-1679

Italian mathematician and physiologist who developed a three-forces theory to explain the elliptical orbits of Jupiter's satellites (1666), which influenced Isaac Newton's work on universal gravitation. Borelli's observations of comets helped undermine the Aristotelian concept of the heavens by showing their absolute distance from Earth changed and that they were above the Moon. He also correctly explained muscular action and bone movements in terms of levers, but incorrectly attempted to extend this analysis to the internal organs.