The discovery in twentieth century that the universe is not an unchanging, eternal entity was a complete shock to secular minds. It was utterly unanticipated.
Early Christian and Muslim scholars used mathematical reasoning to demonstrate that it was impossible to have an infinite past. Because an infinite past would involve an actually infinite number of invents, their conclusion was that the universe's age must be finite. That is, it must have had a beginning.
Here is an example involving marbles: Imagine I had an infinite number of marbles in my possession, and I wanted to give you some. In fact, suppose I wanted to give you an infinite number of marbles.
One way I could do that would be to give you the entire pile of marbles. In that case I would have zero marbles left for myself. Infinity minus infinity equals zero.
Another way to do it would be to give you all of the odd-numbered marbles. Then I would still have an infinity left over for myself, and you would have an infinity too. Infinity minus infinity equals infinity.
Or I could give you all of the marbles numbered four and higher. That way, you would have an infinity of marbles, but I would have only three marbles left. Infinity minus infinity equals three.
Do you realize how the idea of an infinite number of things leads to contradictory results? In the first case, infinity minus infinity is zero; in the second case, infinity minus infinity is infinity; and in the third case, infinity minus infinity is three. In each case, we've subtracted the identical number from the identical number, but we have come up with nonidentical results.
That's because the idea of an actual infinity exist only in our minds. Working within certain rules, mathematicians can deal with infinite quantities and infinite numbers in the conceptual realm.
However, and here's the point, it's not the descriptive of what can happen in the real world. The point of the illustration is that you couldn't have an infinite number of events in the past. Substitute past events for marbles, and you can see the absurdities that would result. So the universe can't have an infinite number of events in its past; it must have had a beginning.
In light of all the evidence for a beginning of the space-time universe, the Beginner must be outside the space-time universe. When God is suggested as the Beginner, then who made God? If everything needs a cause, then God needs a cause too.
As we have seen, the Law of Causality is the very foundation of science. Science is a search for causes, and that search is based on our consistent observation that everything that has a beginning has a cause. In fact, the question "Who made God?" points out how seriously we take the Law of Causality. It's taken for granted that virtually everything needs a cause.
So why then doesn't God need a cause? Because the skeptical contention misunderstands the Law of Causality. The Law of Causality does not say that everything needs a cause. God did not come to be. No one made God. He is unmade. As an eternal being, God did not have a beginning, so he didn't need a cause.
But wait, if you can have an eternal God, then I can have an eternal universe! After all, if the universe is eternal, then it did not have a cause. Yes, it is logically possible that the universe is eternal and therefore didn't have a cause.
In fact, it is one of only two possibilities: Either the universe, or something outside the universe, is eternal. Since something undeniably exists today, then something must have always existed; we have only two choices: The universe, or something that caused the universe.
The problem is that while it is logically possible that the universe is eternal, it does not seem to be actually possible. For all scientific and philosophical evidence tells us the universe cannot be eternal. So by ruling out one of the two options, we are left with only other option, something outside the universe is eternal.
When you get right down to it, there are only two possibilities for anything that exists: Either, one, it has always existed and is therefore uncaused, or, two, it had a beginning and was caused by something else, it can't be self-caused, because it would have had to exist already in order to cause anything.
According to the overwhelming evidence, the universe had a beginning, so it must be caused by something else, by something outside itself. Notice that this conclusion is consistent with theistic religions, but it is not based on those religions, it is based on good reason and evidence.
So what is this First Cause like? One might think you need to rely on a bible or some so-called religious revelation to answer that question, but, again, we don't need anyone's scripture to figure that out. Einstein was right when he said, "Science without religion is lame; religion without science is blind."
Religion can be informed and confirmed by science, as it is by the Co