theory three, for me.
i find it highly improbable for a judging being such as god to exist. I could imagine something creating the first *whatever*, from which the universe as we know it developed, but too much of a hypothesis to predict an afterlife, simply because the thought of "nothing" is too abstract for a human to think.
Bluntly: I am, because without me being able to think this, I wouldn't realize the world being. The world world wouldn't "be" to me. A world my senses can not sense, does not exist - to me. And I can not know which never came through my senses into my mind.
Anyway, from the belief of no sense of life comes freedom to do what you want. This leads to free hedonism - the search for the most fun possible. Quite liberating for many, I guess. To me, it's no beautiful conclusion, but I found no way yet, to deny it.
Seems I'm not that good at having fun xD