The Law of Falling Bodies states that the space traversed by a body falling to the earth is directly proportional to the square of the time of the fall. See an animated demonstration of the law of falling bodies on an inclined plane . The reason that we intuitively think that lighter objects fall more slowly than heavy objects is two-fold. First, we have observed very light objects, such as feathers and snow flakes, fall slowly because of wind resistance. Second, we confuse force with speed.
Heavier objects fall with more force because weight is a component of force.
However, speed and force are different measures. Ptolomy was the authority on astronomy in the Ancient World. He maintained that the earth was the center of the universe and that it was stationary and immovable. The stars, the planets, the moon and the sun revolved around the earth in celestial spheres. Everything in the heavens was perfect and unchanging while the earth was corrupt.