It means that if you can't achieve your goal by virtue like a saint, then you can do whatever it takes to achieve your goal. This sentence reflects the requirements of bureaucratic capital in modern China for the development of capitalism.

This couplet comes from Zeng Guofan, a famous minister and "a generation of Confucian generals" in the late Qing Dynasty, and its name is no less than that of Cao Mengde. The first part is "If you are not a saint, you are an animal", and the second part is "Mo Wen gains, but requires cultivation". Its bottom line is not difficult to understand, and now it has become a famous saying; Mr. Wu thinks that the first part is ambiguous and seems to be suspected of philosophy. It was first seen in Zeng's Quezhai Diary (that is, Zeng Guofan's Diary), which was the motto that Zeng followed all his life. Mr. Wu's explanation of this couplet is not unreasonable, but in my opinion, the literal meaning of this couplet should be understood as: you can't be a saint, you can only be an animal; Don't ask about the harvest, just how to plant it properly.