Is the universe a giant organism, and we are a mere facet of it's existence...our lives in this solar system perform some function...
What if we are consciously existing on several different planes at once, but our attention can only focus on one thing at a time, so when we are in this dimension we forget our existence in another. But when we switch to another, we forget our existence here.
What if our ideas and dreams are echos from that other dimension...our multi-planal existence mingling in our subconscious? Can we die in one plane and continue living in another?
What if when we die, we simply resume activities in another dimension, having no idea what happened? What if every time we fall ill, one of our other lives just died?
Anything is possible. We can never know for sure.