It is without a doubt one of the most important facts that sentient beings need to keep in mind when they float through life.
Matter has not been created in billions of years yet life begins and ends, over and over and over again, with these same molecules.
When I speak of reincarnation, THIS is what I speak about. Our spirit returns in the form of the material that once made us in our current and past forms. Sometimes we get lucky and a lot of the same material is used and we are old souls with wisdom beyond our present years. Other times we are just a small piece of them and need to learn the lessons again.
And one day, one day very soon, our pieces will all return to the mass of molecules that has the potential to become, ANYTHING. Until then, well, we get to choose what we become.