Once upon a time there was a serpent who was badly injured in a fight with another animal. It managed to slither away to safety but would have surely died if a benevolent man had not seen it suffering by the side of the road. The goodly man carefully wrapped the snake up and took it to his house, where he bestowed the kindest and gentlest care on the snake until it was healed and could return to the wild. Just as the man was releasing the serpent back into the grass, the ungrateful snake turned and bit him on the hand.
“What did you do that for?” cried the man, who knew that the bite of this particular snake was usually fatal. “Didn’t I take care of you when no one else would?”
The snake shrugged (no small feat for a snake!) and replied to the benevolent–and now doomed– man, “What did you expect? You knew I was a snake when you picked me up.”