This shows that the standards of right and wrong, good and evil are artificial and vary according to time, region (space), customs and habits. It is not feasible if you don't understand the changes of the past and the present, stick to traditional forms of moral standards, and the mud will not be changed. However, nowadays, people don't learn from the past and the present, misunderstand the sense of freedom, and do whatever they love, regardless of others or the interaction in society. This is also the truth of not understanding "practice in shape". Therefore, "only saints can then practice the form". In a certain situation, a certain era, a certain region, we should abide by their customary norms. ( Mencius and Deligence)