Now the whole universe is a vast, interlocking chain of things that come into existence. Each of these things must therefore have a cause. My parents caused me, my grandparents caused them, et cetera. But it is not that simple. I would not be here without billions of causes, from the Big Bang through the cooling of the galaxies and the evolution of the protein molecule to the marriages of my ancestors. The universe is a vast and complex chain of causes. But does the universe as a whole have a cause? Is there a first cause, an uncaused cause, a transcendent cause of the whole chain of causes? If not, then there is an infinite regress of causes, with no first link in the great cosmic chain. If so, then there is an eternal, necessary, independent, self-explanatory being with nothing above it, before it, or supporting it. It would have to explain itself as well as everything else, for if it needed something else as its explanation, its reason, its cause, then it would not be the first and uncaused cause. Such a being would have to be God, of course. If we can prove there is such a first cause, we will have proved there is a God.
Why must there be a first cause? Because if there isn't, then the whole universe is unexplained, and we have violated our Principle of Sufficient Reason for everything. If there is no first cause, each particular thing in the universe is explained in the short run, or proximately, by some other thing, but nothing is explained in the long run, or ultimately, and the universe as a whole is not explained. Everyone and everything says in turn, "Don't look to me for the final explanation. I'm just an instrument. Something else caused me." If that's all there is, then we have an endless passing of the buck. God is the one who says, "The buck stops here."...
Many [philosophers] say the proofs don't prove God but only some vague first cause or other. "God of Abraham, Isaac, and Jacob, not the God of philosophers and scholars", cries Pascal, who was a passionate Christian but did not believe you could logically prove God's existence. It is true that the proofs do not prove everything the Christian means by God, but they do prove a transcendent, eternal, uncaused, immortal, self-existing, independent, all-perfect being. That certainly sounds more like God than like Superman! It's a pretty thick slice of God, at any rate—much too much for any atheist to digest.
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