ocr: From these theories, Leonardo assumes the same may be true of the earth's moon and thus writes ofits watery surface. The persona ofhis famed 'adversary" argues that any water on the moon would naturally fall to the earth by the action of gravity. Leonardo retorts that if the moon's water fell, the moon itself would fall, adding: "Therefore, not falling, itisa clear proof that the water up there and earth are sustained with their other elements,just as the heavy and light elements down here sustain themselves In a space that is lighter than themselves. AIn - effect, he concludes that the moon h ...