When I was twenty I thought that life came to a point in some openly dramatic way (like in the movies) and somehow you got into adulthood at some point and then you were set, on a plateau that went on forever and ever. Remember the contralto in Pirates of Penzance, accused of being old and of having wrinkles and gray hair? And she defends herself by saying (singing, rather), "They gradually got so." When I was twenty-five and sang in the chorus, my mother laughed and laughed at that line and I wondered why.
All my best,