Why I know I was born an atheist

Well I actually remember the time in my life when I first thought about death. My dad was reading me a children's book called "The Five Chinese Brothers." I know what house I was in, so I have an idea of my age (about 3 or 4). The book touches on death, so I tried to imagine what it would be like to be dead. I grew up in a science oriented community (my dad worked as an engineer at a remote government lab, so the gov provided all the engineers and scientists there with housing). My older brother was a huge science nerd... he was probably about 13 or 14 at the time... so I'm sure he'd been telling me all about the Apollo missions that were going on then. So I imagined that being dead was like floating in outer space: completely black and soundless... this terrified me at first... but then I realized (to my great relief) that I wouldn't be there to experience it!  I did not invent a god or an afterlife. I had not had any religious training yet: no bible stories, or anything like that. I did get that later on in catechism classes, but at that point none of those stories (about god or an afterlife) occurred to me.

Thus I was an atheist by default (an implicit atheist) even at that age. (3 or 4).

Some illustrations from "The Five Chinese Brothers":