Something that's been bugging me lately is that the popular concept of reincarnation is linear. Life after life, starting long ago and moving closer to the present life each time. Bridey Murphy as an example. Why does it have to be liear though? It's pretty much a given that we are vehicles for immortal souls that come to this plane, or level, or reality, to learn or experience in a body made of mud that which it can't on it's own level or reality.
So, if that's true, then let's take it a step further, assuming that that immortal soul instead of inhabiting a single body, life after life, past to future, instead actually inhabits no body at all, but controls, possibly through the silver cord linking the earthly body to the astral, many bodies in many eras, epochs even, worlds even. Hundreds, or thousands, or millions, or billions, or trillions, of lives lived, experienced, learned from. Which could mean that each of the billions of persons on the Earth could belong to a single soul. Not billions of souls as is popularly believed, but just one soul controlling billions of beings and learning, and experiencing a billion things at once.