The Scientific Revolution represented a major change in views of the physical universe that began in the 17th century. Prior medieval science was based on reasoning and tradition rather than experimentation. The Scientific Revolution established new principles of science based on questioning old assumptions, empirical evidence through experimentation and observation, and reason over religious dogma. Major developments included Copernicus establishing a heliocentric model of the solar system, Kepler's laws of planetary motion, Galileo's astronomical observations with the telescope, and Newton's formulation of universal gravitation and the laws of motion.