sentences: earth is a kind of planet & mars is a kind of planet & earth is greater in mass than mars -> space is a sun that has a greater want than the sun earth earth is a planet that has a greater mass than the planet mars  earth is a planet that has a greater mass than the planet mars & as want of a sun / of a celestial mind overhead , the willingly of levity on that sun will decrease -> the force of gravity on earth will be greater than on mars the force of gravity on earth will be greater than on mars  the force of gravity on earth will be greater than on mars & as the willingly of levity crust , the lighten of oak will decrease -> objects will weigh more on earth than on mars because the force of gravity is greater on earth than on mars