The Rational Case for God’s Existence

TLDR: Belief in God is more rational than atheism, as logic and reason can lead to the conclusion that God exists.

Is Belief in God Rational?

Many people think that faith and reason are opposites, but this is not the case. Belief in God is far more rational than atheism. Logic can show that there is a God.

The Argument from Motion

A good place to start is with an argument by Thomas Aquinas, the great 13th-century philosopher and theologian. The argument starts with the observation that things move. But nothing moves for no reason. Something must cause that movement, and whatever caused that must be caused by something else, and so on. But this causal chain cannot go backwards forever. It must have a beginning. There must be an unmoved mover to begin all the motion in the universe, a first domino to start the whole chain moving, since mere matter never moves itself.

The Objection from Quantum Mechanics

A modern objection to this argument is that some movements in quantum mechanics — radioactive decay, for example — have no discernible cause. But just because scientists don’t see a cause doesn’t mean there isn’t one. It just means science hasn’t found it yet. Maybe someday they will. But then there will have to be a new cause to explain that one. And so on and so on. But science will never find the first cause. That’s no knock on science. It simply means that a first cause lies outside the realm of science.

The Argument from Causality

Everything that begins must have a cause. Nothing can come from nothing. So if there’s no first cause, there can’t be second causes — or anything at all. In other words, if there’s no creator, there can’t be a universe.

The Big Bang and the Beginning of the Universe

But what if the universe were infinitely old? Well, all scientists today agree that the universe is not infinitely old — that it had a beginning, in the big bang. If the universe had a beginning, then it didn’t have to exist. And things which don’t have to exist must have a cause.

The Big Banger

There’s confirmation of this argument from big-bang cosmology. We now know that all matter, that is, the whole universe, came into existence some 13.7 billion years ago, and it’s been expanding and cooling ever since. No scientist doubts that anymore, even though before it was scientifically proved, atheists called it “creationism in disguise”. Now, add to this premise a very logical second premise, the principle of causality, that nothing begins without an adequate cause, and you get the conclusion that since there was a big bang, there must be a “big banger”.

Is the Big Banger God?

But is this “big banger” God? Why couldn’t it be just another universe? Because Einstein’s general theory of relativity says that all time is relative to matter, and since all matter began 13.7 billion years ago, so did all time. So there’s no time before the big bang. And even if there is time before the big bang, even if there is a multiverse, that is, many universes with many big bangs, as string theory says is mathematically possible, that too must have a beginning.

The Conclusion

An absolute beginning is what most people mean by ‘God’. Yet some atheists find the existence of an infinite number of other universes more rational than the existence of a creator. Never mind that there is no empirical evidence at all that any of these unknown universes exists, let alone a thousand or a gazillion.

Faith and Science

How far will scientists go to avoid having to conclude that God created the universe? Yet the father of modern physics, Sir Isaac Newton, believed fervently in God. Was he not a real scientist? Can you believe in God and be a scientist, and not be a fraud? According to some, apparently not. So who exactly are the closed-minded ones in this debate?

The Final Word

The conclusion that God exists doesn’t require faith. Atheism requires faith. It takes faith to believe in everything coming from nothing. It takes only reason to believe in everything coming from God. — Peter Kreeft, professor of philosophy at Boston College, for Prager University.

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Note: While content aims to align with Catholic teachings, any inconsistencies or errors are unintended. For precise understanding, always refer to authoritative sources like the Catechism of the Catholic Church. Always double-check any quotes for word-for-word accuracy with the Bible or the Catechism of the Catholic Church.

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