Being practical and upholding one’s moral duties were important ideas disseminated by Zhou Zuoren around 1933. It was meant to express intellectuals’ responsibilities during the Sino-Japanese War. However, after his defection to the Japanese, the context was changed, and history did not evolve as he expected. His call for a practical interpretation of moral duties degenerated from a lofty expression of responsibilities to a low excuse for his own immoral behavior. Zhou Zuoren tried to find a theoretical way to face the problem of nation-state identity during the Japanese occupation, but failed. What he wrote in the reminiscences in his late years implies that he did not believe in the practical interpretation of moral duties, revealing his guilt for betraying the nation.