Ask a 20-year-old who is old and she is likely to say anybody over 40. At 30 you are likely to shift that to maybe 50. At 40, 60 is old. Our perception of who is old keeps moving as we age. Not long ago, an 82-year-old very seriously spoke to me about “that young man of 50”. But it is true that the answer to “who is old” has changed from what it was a hundred years ago. That’s because, the “who is old” question needs to be seen in the context of life expectancy, or the age at which an average person dies. World Bank data puts this number at 52.5 for the world in 1960 and at 71.8 in 2015. The generation that will live to be a 100 may have possibly already been born.
The answer of “who is old” matters in ways that have nothing to do with vanity. It matters to each of us and it matters to a world that is living longer and longer.