The Art of War by active 6th century B.C. Sunzi

33. If there is disturbance in the camp, the general’s authority is

weak. If the banners and flags are shifted about, sedition is afoot. If the officers are angry, it means that the men are weary. [Tu Mu understands the sentence differently: "If all the officers of an army are angry with their general, it means that they are broken with fatigue" owing to the exertions which he has demanded from them.]