What I am saying is that Jabba observing his own existence is a foregone conclusion under both of his hypotheses; therefore, his observing his existence is useless for discriminating between those hypotheses.
If I'm understanding it correctly, your argument is that his P(E | H) is implicitly P(E | H, E) and likewise for ~H, because it's impossible to observe your own non-existence, and hence P(E | H) = P(E | ~H)? You seem to reach the same conclusion as me, that contrary to his claims his likelihoods are equal, but I don't think your argument for it is correct.
To see this, let's introduce the hypothesis G being "the electrical wire is live" and ~G being "the electrical wire isn't live", and E is still "I exist". G here has the same function as H in
Jabba's argument. Let's use, say, P(E | G) = 0.01 and P(E | ~G) = 0.99. Here you should argue the same thing, that because it's impossible for me to observe my own non-existence, what I implicitly have would be P(E | G, E) and P(E | ~G, E), both of course being 1. Yet it is clearly true that, after having touched the wire and having survived, I should conclude that the wire likely wasn't live.
It's trivially true that you can not observe your own non-existence, but that doesn't mean anything and you can't just insert E into the likelihoods like that.
I don't think anyone is saying that you can never make a deduction based on your own existence.
Yet that seems exactly what some people have done with the Texas Sharpshooter/special case argument. Because his E is "
I exist" therefor he is considering himself a "special case" hence error. This is false, as can be seen above by keeping E the same but changing the H to the electrical wire thing.
If I misunderstood that particular argument then please explain.
The HARKing argument seems to be that, because his E is considered after the fact (ie he hypothesizes about it after he already knows that he exists) therefor error. Yet by the same substitution of G for H, and assuming I just now started hypothesizing about a wire from 10 years ago, that in no way negates the argument regarding that wire from 10 years ago.
Also, if I misunderstood then please explain.
I thought you had also written that you agreed that the conjunction fallacy applied to Jabba's argument. Am I misremembering, or did you change your mind about that, because I fail to see how it applies.
I thought that at some point he made a claim about the probability of his body existing to be lower than the probability of both his body and his immortal soul existing. If I'm wrong then I'll gladly withdraw my claim. Personally I'm not all that fond of "fallacy-calling" as a method of debate anyway, a fallacy is just a name for a particular reasoning error, and if someone makes such a reasoning error then their opponent might just as well simply explain the error.