The absurdity of the idea isn't relevant, neither is the truth of his existence/non-existence, what matter is what is reasonable to believe given the evidence available - There is no evidence for any malevolent deities, nothing what-so-ever indicating that one exists and the universe is not better explained by one than it is by his absence, therefore there is not reasonable to believe in one - If it is not reasonable to believe in this deity then any doubts raised regarding his non-existence are also not reasonable.
Thus, I can say that beyond all reasonable doubt, such a being does not exist.
Keep in mind 'beyond reasonable doubt' does not mean 'necessarily'. A parallel case might be a trial, A man is accused of murdered his wife, the murder weapon has his prints on it and he was known to have threatened her, the neighbours testified that they were having an extremely heated argument prior to the event, the man's defence is that "someone was sick of us arguing so he put a knife in my hand and stabbed her with it" - There is however no evidence of this person existing and no reason to believe he does exists, the situation is not better explained by this mystery man it is made worse - This is still a doubt over the guilt of the man murdering his wife, but this doubt is NOT a reasonable one.
Any time you are not talking about necessity you leave open the potential for doubt, this doesn't make the doubts reasonable.
Thus, I can say that beyond all reasonable doubt, such a being does not exist.
Keep in mind 'beyond reasonable doubt' does not mean 'necessarily'. A parallel case might be a trial, A man is accused of murdered his wife, the murder weapon has his prints on it and he was known to have threatened her, the neighbours testified that they were having an extremely heated argument prior to the event, the man's defence is that "someone was sick of us arguing so he put a knife in my hand and stabbed her with it" - There is however no evidence of this person existing and no reason to believe he does exists, the situation is not better explained by this mystery man it is made worse - This is still a doubt over the guilt of the man murdering his wife, but this doubt is NOT a reasonable one.
Any time you are not talking about necessity you leave open the potential for doubt, this doesn't make the doubts reasonable.
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