Speakpigeon said:
And that would be wrong. There are two cases where both P1 and P2 are true. Something you could check easily enough for yourself.
No, what I said is that if P2 is true (i.e., if S2 is false, i.e., if you do not pray), then P1 is false
No.
P1 and P2 can be both true
and at the same time. That's what I meant here. So, it not true to say as you do here that if P2 is true, then P1 is false.
EB
I already explained to you that if P2 is true, then the consequent of P1 is false, so (again, assuming P2 is true) P1 is true if and only if its antecedent is also false, i.e., if and only if it is false that there is no god, iff there is a god. So, again, granting that you do not pray (so, P2 is true), it's obvious to me that P1 is true if and only if there is a god. Since I have no good reason to believe there is a god, and it's transparent to me that P1 is true iff there is a god, I also have no good reason to believe P1 is true, given that P2 is.
Now, you say that P1 and P2 can be both true at the same time. If you're talking about the statements by their logical form (and regardless of meaning), and you're always using the material conditional "if", then sure. When you include what the statements actually are, it's apparent that they're both true (as material conditionals; else, you equivocate on "if" as Bomb#20 explained in the other thread) if and only if you do not pray (which is true) and there is a god. But since I have no good reason to believe there is a god, I have no good reason to accept P1.
Alternatively, you can take a look at Bomb#20's proof, which is probably clearer. A subtlety: his argument is somewhat different from mine because he points out that you're equivocating on "if" because you use it to refer to both the material and the counterfactual conditional, whereas I assumed for the sake of the argument in that reply that it is a material conditional throughout your argument, in which case the problem is that P1 and P2 are transparently both true if and only if you do not pray and there is a god, so given that I grant that you do not pray, obviously I have no good reason to accept P1 since I have no good reason to believe there is a god.
But I think Bomb#20's reply is clearer than mine, so I recommend it.