Quote by Walter Isaacson
““Occasionally Leonardo appended a moral lesson to the entry, such as this: “The oyster, when the moon is full, opens itself wide, and when the crab looks in he throws in a stone or seaweed and the oyster cannot close again, whereby it serves for food to that crab. This is what happens to him who opens his mouth to tell his secret. He becomes the prey of the treacherous hearer.””
