When I was about 4 or 5, yet I don't remember the moment that triggered it, maybe because I went to a catholic school that that day we learnt about heaven or something along those lines. It's something that hung over me for years, what happens next? Is there an afterlife? What if I was born into the wrong religion? But then in my twenties, I finally accepted death as a fact of life.
I know it is coming, and I do not fear it, because I believe there is nothing on the other side of death to fear. I hope to be spared as much pain as possible on the approach path. I was perfectly content before I was born, and I think of death as the same state. What I am grateful for is the gift of intelligence, and for life, love, wonder, and laughter. You can't say it wasn't interesting. My lifetime's memories are what I have brought home from the trip. I will require them for eternity no more than that little souvenir of the Eiffel Tower I brought home from Paris.