Is there only a stone metaphor to sum it up?

No, Yu Zhi and Shi Yu are two different people. Although the names are similar, they are also two independent names. Yu Zhi is a modern writer in China. Representative works include Ten Years of Life and Death and After the Spring Rain in Lin 'an. Yu Shi, an ancient writer in China, was active in the Tang Dynasty, leaving many excellent poems and works, and was known as the master of the Tang Poetry School.