*Sighs* I wonder why I'm wasting my time even trying but...
*And yes I am way, massively oversimplifying neurology here to make a point...*
Let's say there is X number of neurons, glia cells, neural stems cells, and so forth in an average human brain.
Let's say there is Y number of ways those neurons, glia cells, neural stem cells, and so forth can be arranged in a functioning brain.
X times Y gives up a (just for the sake of this argument) a total number of possible neurological configurations for a human brain. We could, if we squint sideways and really, really stretch the definition, call these "potential selves" if we want to speak really off the cuff, non-technically and not very usefully.
So (X times Y) is this... *scoffs* mythical pool of "potential selves." This number is massive. It is not infinite nor practically infinite or any other meaningless begging the question special pleading term but let's say it's just mind boggingly huge, fine.
So we compare (X times Y) to Z where Z is the total number of "People" who have ever existed which (and yes this is a totally nearly meaningless term I know bear with me...) let's use the 107 billion figure that the BBC used to answer the "Do the dead outnumber the living?" question.*
So the ratio of Z to (X times Y) does fit working definition of the useless, made up, pointless equation Jabba keeps alluding too.
(And yes I know there is a crap ton wrong with this, I know, I know)
Even given all that and ignoring the career anyone with even a layman's knowledge of neurology or statistics could make out of listing everything wrong with that... even given all that..
IT STILL DOESN'T WORK!
Out of all those "Potential selves" there is nothing that makes "Selves" of me, Jabba, Hitler, Churchhill, or every other Tom, Dick, and Harry currently or previously alive any more or less likely then all the potential "selves" that didn't exist.
How this is an after the fact rationalization and a Texas Sharpshooter fallacy has been explained to Jabba multiple times.
I've dismissed Jabba's nonsense several times as reducible to "If accept that I am right, then I am right" but it doesn't each reach that level.
Even if I agree with him, I can't agree with him. He has a false pretense that doesn't even lead to his false conclusion.
*
http://www.bbc.com/news/magazine-16870579