To know, is to know that you know nothing. That is the meaning of true knowledge. When you say something, say what you know. When you don't know something, say you don't know. That is knowledge.
If names are not correct, then language is not in accord with the truth of things. If language is not in accord with the truth of things, then affairs cannot be carried out successfully.
Be faithful and true of word; let thy walk be plain and lowly: thou wilt get on, though in savage land. If thy words be not faithful and true, thy walk plain and lowly, wilt thou get on, though in thine own home? Standing, see these words ranged before thee; driving, see them written upon the yoke. Then thou wilt get on.
Let the states of equilibrium and harmony exist in perfection, and a happy order will prevail throughout heaven and earth, and all things will be nourished and flourish.