Looking at modern society, we see a dramatic increase in the number of middle-aged persons returning to school, women who are past menopause having children, senior athletes still performing well, and middle-aged TV and movie stars posing for nude photographs. In the US, the 77-year- old John Glenn attracted the world's attention when he returned to space last year.
放眼現代社會，重返學校就讀的中老年人劇增、已過更年期的女性仍能植入受精卵懷孕生產、老年運動員叱吒體壇、高齡的影視偶像拍寫真集，美國七十七高齡的太空人葛倫上太空更成為舉世注目的焦點… …。