Old age was growing inside me. It kept catching my eye from the depths of the mirror. I was paralyzed sometimes as I saw it make its way for me so steadily when nothing inside me was ready for it.

Simone de Beauvoir (1908-1986) French author, existentialist philosopher, feminist theorist

Force of Circumstance [La Force de Choses], Part 1 ch. 4 (1963) [tr. Howard (1965)]
    (Source)

At age 41.