It means that if you can't achieve your goal by virtuous means like a sage, then you can achieve your goal by unscrupulous means. This sentence reflects the requirements of the development of capitalism by bureaucratic capital in modern China.

This couplet comes from Zeng Guofan, a famous minister in the late Qing Dynasty and a generation of Confucianism, whose name does not diminish that of Cao Mengde. The first part is "If you are not a sage, you are an animal", and the second part is "Mo Wen reaps, but asks for cultivation". Its bottom line is not difficult to understand, and now it has become a famous saying; Mr. Wu thinks that there are some ambiguities in the Part I, which seems to be suspected of Cao Mengde's philosophy. Originally seen in Zeng's Diary of Quezhai (that is, Zeng Guofan's Diary), it 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: if you can't be a sage, you can only become an animal; Don't ask about the harvest, just ask how the cultivation is more appropriate.