I think, therefore I'm not sure

Lazy Philosophizing

The subjective improbability of existence has always puzzled me.  In some ways it seems a blatant and outrageous fact, yet it defies any objective description which can capture the incredulity felt subjectively.

It goes like this. I didn't exist.  I wasn't here in, for example 3rd of March 1950.  I won't exist on the 3rd of March 2090.  There is only a very small and noticeably finite time that I exist.  So how come 'now' is within that tiny time that I exist?  And why am I at all? If any one of a zillion dice rolls had turned out differently I wouldn't ever have been, assuming this corporeal thing is the only thing that ever could be me.  I'm looking at total improbability.  And yet it is the case.

Objectively viewed there's no problem.  Any self aware creature that crawled out of the slime would have this egotistical perception.  They would say that wouldn't they?  But it's baffling when you are that creature. The objective explanation doesn't help my predicament and,  if you share my line of reasoning, it doesn't help with yours either.

If you take the subjective view,  it can lead you to the following theories of existence:

1) I'm here.  It was an amazing occurrence of incalculable improbability.
2) In some way it was inevitable that I was here and that I am always here,  although memory fails me on what exactly I was doing on 3rd March 1950
3) I'm not really here at all

In terms of theories,  2 and 3 pose no statistical challenges.  Both effectively say that nothing improbable is going on (if you buy the theory).  1,  is effectively the null hypothesis,  and given it's self-professed total improbability must be wrong.

So what about the idea that we are continuously existent?  the theory that this point of awareness is just passing through a body,  that it came from another,  that it will pass on to another.  And in between the changes,  drafts from the waters of lethe conveniently take away the memories from one phase to the other. Internally, the maths of this just don't stack up:  there are more people now than there were.  Where did these new ones all come from?  oh yeah,  I know,  they used to be Tigers.  But what about when there wasn't any life on earth?  And in any case in what sense is the existence continued?  The only way I can distinguish myself from others is by my memory,  however recorded,  from the outward appearance of my body to the hidden memories in my head. These are the things that prevent me and others from mistaking me for someone else.Take them away and there's no continuity.

The other theory is to say that the self is an illusion.  This sounds great, but how exactly does that work? I can't decide to suddenly be in a different body with a different set of memories.  I'm stuck with this one. The good old cogito ergo sum is very persuasive.  It keeps telling you that you *do* exist.  I suppose a 'selfless' version would be "something is thinking therefore the thinking thing exists" but no matter how I cut it,  I'm not able to be Descartes.

I'm too lazy to bother reading loads of stuff.  I'm presuming this line of thought has a lot of history and has a name and everything but I'm not aware of what it is.  Anybody got some pointers?