You can't judge a book by its cover. This Chou Shi is like this. There are many standards, or angles, to judge the value of a person or a thing. The same thing, measured by different standards or from different angles, draws different conclusions. A pear looks like a gourd from the front and a circle from the bottom up, which is the change of cognitive feeling brought about by the change of angle. A smooth hair will become more rugged than a mountain under a high-power microscope, which is a cognitive change brought about by the change of standards. From the perspective of ordinary people, Chou Shi is useless and extremely ugly when measured by the general use of stones; However, in the eyes of scientists, judging Chou Shi by scientific standards unknown to ordinary people, it has deep roots and great uses, is unknown and indisputable. Therefore, Ugly Times takes ugliness as beauty and hides beauty in secular ugliness. The author convinces people by reasoning, and through strong contrast, shows the noble character of ugliness, obscurity, unyielding misunderstanding and fear of violence.