When Confucius saw a person wearing clothes of mourning, even if it was someone he saw every day, his face would express grief. When he saw someone wearing a court cap or a blind person, even if it was someone he saw every day, he would become solemn.
If Confucius was riding in his carriage and he came across someone in mourning, or someone carrying official documents, he would bow down and grasp the crossbar.
If he was served a rare delicacy at a banquet, he would rise and express his appreciation.
He would also change his expression at the clap of thunder or a strong gust of wind.