A cook once roasted a duck for its master. He looked so delicious that he could not resist the temptation and ate up one of the drumsticks. When he sat down to eat the meal, he quickly noticed the missing leg. He asked him what had happened to the other leg. The cook told him that it had one leg only. The master said that there was no such thing as a one-legged duck but the cook insisted that every duck had only one leg.