metis
aged ecumenical anthropologist
Another thing too, even if (let's say for sake of argument) that God did exist without having a cause. He/she created the universe with a purpose. He/she must've had some kind of idea, plan, thought, blueprint, reason for the creation. This means a sequence of thoughts for the planning. That sequence of thoughts must've had a beginning. So the act of causing the universe wasn't the "First Cause" but rather that "First Thought." But... did God really not think about before that? Was that thought just a random thought? Like "Oh, I havent' thought about this before, but maybe I should create something, perhaps a universe? What is a universe? Let's think about that for a second." Well. Then the actual first cause was random! So at some point either we get a random event or we have an eternal/infinite regression.
The above is a very good point, imo, and where I first ran across it was with the Buddhist monk and former scientist Matthieu Ricard. On of his points is that if there's a creator-god, then this deity must change at least somewhat because one must change at least a bit in order to bring about change. And if this creator-god changes even a smidgen, then something outside of itself must prompt it in some way to change.
It's certainly not proof in and of itself, but it is logical, and what else do we have to work with?