I've been living for thirty-seven years. That's not terribly old by today's standards, but a long time has gone by. Richard Nixon was President of the United States when I was born, all four Beatles and Elvis Presley were still alive, the Vietnam War wasn't over yet, and the United States had not launched its first space shuttle mission.
During those thirty-seven years, many people have come and gone in my life: grandparents and other older relatives, friends, schoolmates, teachers, prominent historical figures and celebrities I've never met, etc.
It's amazing to reflect upon the large numbers of people you meet during a lifetime, and how often, they are an important part of your daily life for years and years, and then leave your life through various circumstances and are never heard from again. Think back to people you went to school with: some of them were close friends, undoubtedly, whom you saw day after day, year after year. Then, everybody graduates and goes on to separate lives...often never again seeing or speaking to people with whom they had spent many days together over the course of years.
Very close friends and relatives aside, many of the people I was close to ten years ago are no longer a part of my life (or I, of theirs). This is even more the case for people I knew twenty years ago...or thirty. It's like they never existed, and yet you remember some of them and wonder how people drift apart over the course of a lifetime. I'm quite convinced that twenty years from now, if I'm still living, the people with whom I associate daily will be people I'm not even acquainted with now, while most of the people I associate with daily today will have gone on to fates unknown to me.