Buddhism

natural energy that created your life, my life, every life on earth and elsewhere. Only "no-thing", an absolute vacuum, is truly dead. Even the most seemingly inanimate object is full of energy, subatomic life zooming with energy, mocking the macroscopic levels it creates and is created from. The brick in the wall, seemingly inanimate, seemingly lifeless, still possesses tremendous energy of all it's atoms, "holding" the air away, the bricks above it, and takes more energy than it possesses to be overcome.
Yes you will reincarnate somewhere, but think about this: what really are the chances you will reincarnate on earth immediately after this life?
The sun's rays, just as every star, radiate 360 degrees, three dimensionally. Radiating away from our energy source, not stopping until they encounter, become a part of, or bounce away from an object. That object may be a small particle near the sun. It may be another space body an unfathomable distance from us.
Once dead, there are no words, no thoughts. You're still, however, just kind of "there". It can be disorienting after years living in the animal you reside and it will feel, immediately, "cold". You will seek warmth, other energy, move through other living and (seemingly to us, non-living) beings, experience their thoughts, sights, sounds, fears, energy for a short time. Eventually, you will "expand". This is very, very difficult to put into words, there just aren't adequate sets of them to describe the experience. Once you do, you will: "go into the light". Time becomes meaningless as you travel with it, then somehow, somewhere, you will rejoin the matrix of another life.
The natural cause you seek is all around you. It will not "speak" like the supernatural we define. God, the devil, santa klaus and the easter bunny will melt away.

"I've been dead once, it's very liberating" -- Jack Nicholson as the Joker in "Batman".