The document summarizes a fable called "The Dog and the Shadow". It tells the story of a dog that carries a piece of meat in its mouth to eat at home. As it crosses a plank over a brook, it sees its shadow in the water below and mistakes it for another dog with meat. When it snaps at the shadow, it drops its real meat into the water. The moral of the story is to "beware lest you lose the substance by grasping at the shadow".