I enjoyed reading your response here Greenslade,

I do think it's a very big question that is being posed here personally because as I see it proceeds from the point of view that life is fixed in the here and now , these two alone support the concepts of both time and space. It seems to suggest that this you now is the only you now.

But theres always that odd anomaly (or perfectly normal depending on your point of view) of dreams. dreams whereby the consciousness seems to be able to visit the future and the past. Consciousness appears quiet mercurial to me any way, Even in waking life now, I would suggest that you are not the same person as you were 10 years ago. Even on a day to day basis, The Person relaxed is not the same person fixed in concentration.

Then there's progressive hypnosis of course, Like regression hypnosis only you are hypnotized and taken to a future life..so you begin to see how it go's beyond time and space a little.

I have not here even begun to explore the particular branch of quantum mechanics which suggests parallel universes exist, with versions of us in them as I think it would muddy the waters.

I can sum it up simply by using an often used cliche. " He has not been himself lately" or "She is not her usual self"...Who are they then ? Where did the other one..The one we know go?

As I was saying, It is a very big question posed the OP