21. Evidence for God's existence - The Contingency argument

God is the best explanation why anything at all exists. This is the most fundamental question of philosophy. Suppose you were hiking through the woods and found a ball lying on the ground. You would naturally wonder how it came to be there. If your hiking buddy said to you, “Forget about it! It just exists inexplicably!”, you would think that he was either joking or else just wanted you to keep moving. No one would take seriously the idea that the ball just exists without any explanation. Why not? Because the ball is contingent in its existence. It can exist, but it doesn’t have to exist.

So what makes the ball different from, say, unicorns, which can exist but do not exist? Very simply, there is something that explains the ball’s existence, typically a causal explanation. Now, notice that merely increasing the size of the ball, even until it becomes coextensive with the universe, does nothing to provide or remove the need for an explanation of its existence. So, what is the explanation of the universe, where by “the universe” or all of spacetime reality? The explanation of the universe can be found only in a transcendent reality beyond the universe, beyond space and time, which is metaphysically necessary in its existence. Now, there’s only one way we can think of to get a contingent entity like the universe from a necessarily existing cause, and that is if the cause is a personal agent who can freely choose to create a contingent reality. It therefore follows that the best explanation of the existence of the contingent universe is a transcendent personal being, which is what everybody means by “God.”

We can summarize this reasoning as follows: