Adou's Bagua. On the morning of May 30, 1974, he suddenly expressed a desire to meet someone, and hoped to do so within an hour. This was quite rare in his later years. After a few casual greetings, he immediately said, 'Dr. Li, you are from Shanghai. Is there a sea in Shanghai?' Li Zhengdao was quite surprised and did not expect such a strange question, momentarily taken aback. After a few seconds, he replied, 'I don't know about that.' He then continued, 'Where there is Shanghai, there is the sea; otherwise, it doesn't make sense. The sea is a town.' It turned out he wanted to discuss with Li Zhengdao the concepts of symmetry and asymmetry, as well as balance in physics. He also had a deeper understanding of various physical theories, discussing everything from cosmic time to space, from fundamental particles to electromagnetic waves. His historical contributions will be judged by history, but he was a person who loved learning and was full of interest in new things, with an active mind and a non-conservative attitude. He even made efforts to learn English. He said, 'In the past, there was no time to study science, which left me with regrets.' I believe if he were still alive and learned about encryption and blockchain technology, he would also have a keen interest; he is a person of eternal significance. Li Zhengdao later recalled, 'At that time, he was already 81 years old, and his movements were not very convenient, but his quick reaction speed, agile thinking, and attention to and understanding of the frontiers of physical science were truly admirable and worthy of respect.'