Yang Chu's younger brother, named Pu, went out one day wearing a suit of white clothes. It came on to rain, so that he had to change and came back dressed in a suit of black. His dog failed to recognize him in this garb, and rushed out at him, barking. This made Yang Pu angry, and he was going to give the dog a beating, when Yang Chu said: 'Do not beat him. You are no wiser than he. For, suppose your dog went away white and came home black, do you mean to tell me that you would not think it strange?'