Sort of a complicated question, I'll try to ask. How was I born me and not another?

[FatAndFaithless]

It still doesn't make any sense.  If "you" never existed, then we wouldn't be able to calculate the odds because we wouldn't have a "you" to use in the numerator.  You can't calculate a probability when one of the variables is a giant "unknown" or "incoherence".

So we don't know whether or not being born is just an inevitability, or if it's a huge off chance that only happens to some people, while some people that would have been may have ended up to just be other non conscious matter drifting around in space? Because to me it sounds like somewhere in there, there's something that would be observable and answerable.

Please tell me how we would determine "how many people could have been," and are now "matter drifting around in space."