While the Principia is primarily a work of mathematical physics, there are some interesting theological interludes. In the second edition of the Principia, Newton suggests that comets might refuel the sun, replenishing the energy lost illuminating the earth. Newton’s intuition, informed by his concept of God’s providence, suggested to him that the God-given purpose of comets in the creation was to keep the sun healthy. Such speculation, while consistent with Newton’s view that God sustains the universe