@RexRed,
Just a second, if you define God as a set of contradictions, it is obvious that He cannot exist, not only as physical presence, but as math logic constract as well. Nothing that is self-contrading can exist in logic.
My understanding of God is not after your representation: 1. Omnipotent 2. Omniscient 3. Omnipresent and 4. Good-willed 'Old Man', who is somehow concerned about us and is obliged to protect us from ourselves and from the nonsence we are doing every day.
Actually nothing that is omnipotent can exist in math logic (we are not talking about the physical world yet).
Suppose you are almighty. Can you make a clonning of yourself - obviously yes. This clonning is exact copy of you, so he is almighty as well. If you are still almighty can you beat him in wrestling. Yes. But if you beat him is he still almighty - no. Even accepting that you both are all the time equal, can you change this situation - no.
So you can't make a clonning of yourself, hence you are not almighty, hence an almighty being cannot exist in our understanting of the world, hence the very assumption that God is almighty has as an objective to preset its inability to exist.
What about 'knowing everything'. Can you know the things that are unknowable? Is you knowledge 'stationary' or dynamic? If it is stationary there is no way to get knowing newly appeared things? If it is changing and improving by continuously acquiring new knowledge & skills, your past knowledge could not have been classified as ''all-knowing'.
What about the omnipresence? Can s.th of the physical world be in such quantum state that it is present everywhere at one and the same time? The whole Universe will comprise this thing, only this and nothing else.
What about the good will. Why are some good people suffering and good things happen to bad people? Can a world exist in which good things will happen to good people only, and bad people will be striken by thinders. What will happen when some people are good to some people, and bad and evil to some other people?
The very assignment of the definition of God presupposes that such thing or being or whatever cannot exist. Isn't that Jesuitism: I will present a watermelon rind as a definition of s.th. and then I will prove that this s.th. cannot be anthing else, but a watermelin rind.