Is absence of proof, proof of absence? Do religious people have an advantage in terms of proof?

There are only 2 options:

A. God exists

B. God doesnt exist

One could say, because there is no proof for A, B is true.

One could even say it in a different way: A is true because there is no proof for B.

So to conclude, absence of proof is not proof of absence when you have two contradicting options, both without proof, where one must be correct.

Therefore, we would be dealing with 50% chance of God existing, since by laws of probability, when two options have unknown probability where one option must be true, it is treated as 50% probability.

When probability is equally unknown on both sides, it follows that both sides are equally possible since unknown probability of one side equals unknown probability of the other side.

Its not a proof that God doesnt exist, but it is a proof that their specific "completely good" God cannot exist.

No, there are far more options than that.

There could be multiple gods of different natures. Even if there was only one god there would be as many options as there are permutations of a single god.

Absence of proof can be proof of absence when the proposition in question should by definition produce evidence (proof). If I define rain such that it would fill an open top beaker left in the open, then the lack of water in the beaker is proof that there was no rain.

Absence of proof can be proof of absence when the proposition in question should by definition produce evidence (proof). If I define rain such that it would fill an open top beaker left in the open, then the lack of water in the beaker is proof that there was no rain.

Actually, that would at best only be proof of no detectable rain.

The definition of rain implies detectability. That is the point.

Is absence of proof, proof of absence? Do religious people have an advantage in terms of proof?

The definition of rain implies detectability. That is the point.

So an undetectable rain would be a possibility with any definition which doesnt include detectability.

And its impossible to detect undetectable rain, thus impossible to prove that undetectable rain doesnt exist.

And Christians will never agree to define God as detectable unless he is actually detectable.

Yes, in scientific terminology that would be an "unfalsifiable hypothesis" which by their nature are also useless hypotheses as they predict nothing and can't be differentiated from contradictory hypotheses in the same category.

Any theory of god that falls under this category is also useless for the same reasons. If there is no way to know if the theory is true there is no way to differentiate the theory from competing theories.

What they agree to is irrelevant. They have scripture. The implications of that scripture are inescapable.

They can claim to believe in an undetectable god, but that would require the renouncement of the scripture as the source of their knowledge.

I have never even met a Christian who follows scriptures to the letter and literally.

There is more evidence for aliens that there ever is or will be  for a "god" that is claimed to be Omnipresence refers who exists everywhere all at once. Omnipotence describes an all-powerful god, and omniscience referring to an all-knowing god.

When probability is equally unknown on both sides, it follows that both sides are equally possible since unknown probability of one side equals unknown probability of the other side.

There is more evidence for aliens that there ever is or will be  for a "god" that is claimed to be Omnipresence refers who exists everywhere all at once. Omnipotence describes an all-powerful god, and omniscience referring to an all-knowing god.

Well, I agree, and many will probably lose faith if aliens are detected.

But some will find a way to explain how God created aliens, just forgot to mention it in the Bible.

Probability is determined by using known past examples as a means of assessing the likelihood of future outcomes. So once it is established that the answer is unknown, probability is definitionally excluded.

The ideas at that point shift. Once we get to the unknown we're now into the realm of philosophy. That is, if a proposition is unknowable then we act in accordance with logical defaults. In terms of existence, the default position is that nothing exists until it is demonstrated to exist, which is why the burden of proof is on theists.

Actually, when probability is unknown, it follows that each point of probability (0 to 100) is equally likely. 

That results in average (50%) as what is the obvious position for probability of probability.

That can be your default position, but one can also go with the idea that things dont exist only when demonstrated to not exist

Then one would be in the position of accepting every unproven proposition simultaneously, even when they contradict each other.

This is a contradiction. You're arguing by not knowing what the probability is, we therefore know what the probability is (50%).

As a matter of practicality we would be right to act as if the probability were even because we have no other choice. But that is very different from asserting the probability is in fact equal.

Is the spirit of God a thing?

Then one would be in the position of accepting every unproven proposition simultaneously, even when they contradict each other.

Accepting as possibility, yes, not as total truth.

We know that both options are of equally unknown probability.

This translates to 50% probability, since 50% = 50%.

Think of it with this example. If you were given the option to enter doors which might kill you or do nothing at all, would you enter those doors?

I hope IlDiavolo  takes up his brilliant thread again once he has time to researched further.

That default position is fallacious. To say nothing exists until proven is false. There are many things that exist, have existed long before proven to me.

Until you are presented with a valid reason to take the possibility of their existence seriously, you assume they don't.