What does the mouse in the fortune-telling storehouse mean?

Reese's hamster philosophy comes from Biography of Reese, the original text is:

Li Sizhe, Chu Shangcai also. When I was young, I was a small official in the county. I was terrified to see that the rat food in the toilet of the official residence was unclean and close to the dog. As soon as you enter the warehouse, you can see the mice in the warehouse, eating millet and living under the big guard, and you can't see the worries of people and dogs. So Lisnai sighed: "Man's virtue is like a mouse, in his own ears!" "

Vernacular translation is:

Li Si, a native of Shangcai, Chu, worked as a small official in the county when he was young. When he saw that the mouse in the toilet where the petty official lived was dirty and ate unclean things, the mouse was always frightened whenever someone or a dog approached.

After that, he went to the granary and saw a mouse in it. The mice in the granary are fat and bright, eating food, not afraid of people, swaggering and carefree.

Suddenly Reese felt: whether a person has talent or not is like a mouse, depending on what kind of environment he is in.

Extended data

Reese spent most of his life pursuing legalism. After he was reused by the Qin government, with his outstanding political talent and foresight, he helped the Qin Dynasty to complete the great cause of unifying the six countries and conformed to the trend of historical development.

After the establishment of the Qin Dynasty, Li Si was promoted to prime minister. He continued to assist Qin Shihuang and made outstanding contributions to consolidating the Qin regime, safeguarding national unity and promoting economic and cultural development. He suggested that Qin Shihuang abolish the enfeoffment system and implement the county system. He also put forward the suggestion of unifying the characters, and then made great efforts in unifying laws, currencies, weights and measures, and car tracks.