Pedro Martínez: I'm not sure we fully agree. I say that proof of the existence of something can take many forms. In the case of God, the kalam cosmological argument comes to mind. We know from science that this universe had a beginning in time. We can trace events back to the singularity. We can't go farther back than that. And we know that the universe is expanding. To expand, it must have necessarily come from a starting point. (scientists can back up the process mathematically and they come up to a single point - the singularity). That singularity contained in it all the matter and energy that is now contained in our universe. Before the "Big Bang" there was likely nothing. We can't know. But something set off the Big Bang. You don't get an effect without a cause. God is that Uncaused Cause.