Yan Zi was a famous prime minister of the State of Qi during the Spring and Autumn Period.
One day, Yan Zi went out in a carriage driven by his coachman. The coachman's wife, who had never seen Yan Zi before, wished to see him. Peeping from behind the door, she observed Yan Zi. She was impressed that, despite being the prime minister, he behaved with great modesty. In contrast, her own husband sat under the large canopy, driving the carriage with an air of haughty arrogance, considering himself unexcelled in the world. She felt deeply ashamed of him.
Upon the coachman's return home, his wife immediately asked for a divorce. Baffled and angry, the coachman demanded a reason.
His wife replied, "Yan Zi is less than six chi tall (a Chinese unit of length, about 1/3 meter), yet his heart is filled with aspirations and his mind with knowledge. Though he is the prime minister, he is courteous and treats people prudently. But you? You are a full eight chi tall, yet you forget you are merely a coachman. By the side of the prime minister, you dare to look so cocky, always considering yourself right, and brandish the whip in utter complacency. You are so immodest that I can no longer live with you."
Hearing his wife's words, the coachman felt deeply ashamed. From then on, he became very careful and prudent in his actions and treated people with modesty.
Yan Zi noticed the significant change in the coachman's behavior and inquired about the reason. The coachman told Yan Zi in detail about his wife's criticism. Deeply moved by this, Yan Zi later recommended the coachman to become a da fu (a senior official).