I have 7 more years before I’m 80. Now there’s a thought!
At the end, you simply think differently about things. You notice that a lot of your friends are dead or dying and you may be in the next wave. This puts a different cast on life than when you are beginning and can’t imagine death.
Toward the end, your experiences help you get ready to die. The real object is to have made your life count, to have contributed to the collective experience. That contribution plays back to you. All this seems obvious. Even such a seemingly small thing as rescuing a dog is important.
There are actually two vectors: self-realization and social contribution. In the richest lives, these two merge (think Carter); in the poorest, they split (think Trump).