Through careful study of the names, the subjects, time of birth, literary genre and symmetric pairs in the text, dialogues and conflict in the work, the article objectively defines the basic thoughts of Du chu ty tuong hich van (Proclamation to the Officers), which was not the thoughts against "foreign invaders", but against "internal enemies". The thoughts of struggling against the "enemies" of the officers themselves. They included cowardice, irresponsibility, quiet-seeking and pleasureloving spirit, and personal interests. That was an extremely tough fight which suffered heavy losses. If the "internal enemies" had not been defeated, it was inevitable that we would have been defeated by "foreign invaders". That struggle was extremely .urgent and fierce, similar to the fight against "foreign invaders", so Tran Quoc Tuan used the Proclamation, which was full of militant spirit, as a tool to launch the fight against those "internal enemies". Du chu ty tuong hich van is not only a powerful writing containing militant spirit against "internal enemies", but also a work of deep humane spirit in trusting and heighten the dignity as well as the good inclination of human beings.