God is so quiet

[SteveII]

It would be up to the atheist to explain everything without logical contradictions. Proving that possible worlds semantics must assume existence is a far cry from having an explanatory ultimate for it. You can't use logic to create existence (a concept has no causal power)--you must answer the actual question--why is there something rather than nothing. If you listen to Dean Rickles again, you will notice that he never actually answers the question posed to him. You can say that is a meaningless question, but that is really just part and parcel to admitting you are stuck with a brute fact--a fact you can't explain.

We know the universe exists, and we can prove it.  Have you an example of a nothing that could exist in it's place?

What you don't want to do is interchange the word 'universe' (a concrete contingent object) with 'exist' (a concept). They are not even synonyms. You can easily posit a possible world where something else besides our universe exists. 

To ask why is there A and not B, we first both have to be sure that A and B are possibilities, we know that A (The universe) does exist, there is no, not universe to exist is there ?

Actually, we are NOT asking why there is A and not B. We are asking why is there A instead of not A. In other words "why is there a universe where there didn't have to be one?" 

The reason he says it is meaningless as I understand it is because nothing is not a possible scenario.  It's a bit like asking why is that cloud not a non cloud.

When you say "nothing is not a possible scenario", okay, I don't think that nothing is a possible scenario either (for different reasons). However it seems you might be taking that sentence to mean that the universe must then exist necessarily, in which cae you are very much mistaken. Rickles makes it quite clear that concrete objects (and he mentions the universe as one of his examples) are all contingent entities--relying on something else for their existence. His answer is that the concept of existence must necessarily exist because you need it as a foundation to explain literally everything else. Concepts cannot cause anything. He never told us what he thought the cause of everything else was.