Professor Hyeong-Seog Kim was born in Pyongyang in 1920 and lived a 100-year-old life. After graduating from the Department of Philosophy at Jochi University in Japan, he served as a professor at the Department of Philosophy at Yonsei University after going through a vice principal and a teacher at Joongang Middle and High School. Afterward, he served as a research exchange professor at Harvard in the United States, the director of the Yonsei University Student Counseling Center, and the director of the Yonsei University Institute of Humanities and he has been an honorary professor at Yonsei University since 1985. Regarded as one of Korea's top three philosophers, he is a philosopher and essayist and has worked on his life as a lecturer and writer for 35 years since his retirement in 1985. He emphasizes that the golden age of life is from 60 to 75 years old, and is represented as a 100-year-old philosopher and senior mentor. Even now, he is actively writing, broadcasting, and giving lectures such as <100years old Diary>, <The Dialogue of Eternity and Love>, and < Happiness Preparation>.