On June 1985, at 4 pm, Professor Hua, a famous mathematical superstar, appeared on the platform of Tokyo University. Invited by Japanese mathematicians, he gave an academic lecture on "Some Personal Experiences of Popularizing Mathematical Methods in China". The 75-year-old Hua Lao began to speak Chinese and was translated into Japanese by a translator. Later, I came to China with the consent of the participants and switched to English. The atmosphere of the meeting suddenly became warm and harmonious, and the audience reacted strongly. Hua Lao's leg is not good. He usually walks with crutches. Japanese friends prepared a wheelchair for him. However, he stood there almost all the time talking, and even miraculously walked to a platform about a foot high in front of the blackboard and wrote and scratched on the blackboard. The more Hua Lao talks, the higher his mood becomes. He even took off his coat and tie and talked endlessly.

His speech was vivid, concise and humorous, which won the laughter and applause of Japanese colleagues from time to time. The original 45-minute report time passed quickly, and Hua Lao spoke for another 20 minutes. When Hua Lao finished speaking, he was about to stand up from his wheelchair to express his gratitude when he suddenly fell to the ground-acute myocardial infarction. The on-site doctor immediately rescued him, but all efforts were of no help. At 10: 09 that night, a mathematical superstar who has been famous in the international mathematics field for more than half a century fell down.