What does Qian Zhongshu's Fortress Besieged mainly want to express?

Qian Zhongshu's Fortress Besieged was a famous novel. It mainly talked about a person who was trapped in a siege and had a deep thought and exploration of the outside world and his own heart. Through the story of a typical Chinese family, the novel reveals the complexity of social class and human nature, expressing the author's deep insight into human nature and criticism of social reality. Through describing the relationship between the protagonist Fang Hongjian and his wife Zhao Hsin-mei, the novel reveals the conflict between traditional and modern marriage concepts. In the novel, Zhao Hsin-mei was a well-educated person. He believed that marriage should be a pure love relationship. Fang Hong-chien was different. He was skeptical of traditional marriage concepts and believed that marriage could be a compromise and union. This difference in thinking led to their feelings gradually drifting apart and eventually walking to the edge of breaking up their marriage. The novel also revealed the complexity of human nature through the description of the protagonist Fang Hongjian's character and mental journey. At first, he was a man with noble ideals and beliefs, but as time passed, he gradually found himself trapped in a siege and could not escape the shackles of reality. He experienced the inner struggle and pain, but at the same time, he also felt the cruelty and hypocrisy of social reality. Fortress Besieged mainly wanted to express the complexity of human nature and the defects of social reality, as well as the deep thinking of human nature and the concept of marriage. It is a novel with profound ideology and cultural value, and also a classic of modern Chinese literature.