If you believe in gravity, you should believe in God.

If you are like me, then you have a bank account and a debit card. You have a 4-digit PIN that allows you to spend the money using the card. There is a maximum of 10,000 possible PIN numbers, so the number you chose is pretty rare. It isn’t the rarity of the sequence of your PIN that makes it useful; it is that the rare series of your PIN is specific to your debit card.

This is known as “specified complexity.” Your unique PIN has a level of complexity to it (it’s rarity). That complexity is specific to a real-world object (your debit card). Because your PIN matches your debit card, the bank has confidence that the entered PIN is not random and will release your funds.

We see this same kind of specified complexity in nature. Behind the randomness in our universe is a carefully constructed framework of natural laws that are finely tuned so that life can exist. These laws are complex and specific to the needs of life. If these laws varied by a tiny margin, then life would be impossible anywhere in our universe. Just like with your PIN and your debit card, it seems that this fine-tuning is not random. Let’s review how this fine-tuning gives us an excellent reason to believe that God exists.

So what are the odds?

The numbers involved in fine-tuning are enormous, so let’s get some context first. The odds of winning the lottery are about 1.4 in 10^6. If we had a planet-wide raffle and every human on the planet got a ticket, your odds of winning would be about 1 in 10^9. There have been 10^17 seconds since the big bang, and there are 10^80 atoms in the universe.[1]

Now, on to fine-tuning in the universe. As Douglas Groothius says, “The specific conditions of the universe at large reveal an intricate and finely tuned ensemble of factors that make embodied human life possible.” [2] Two examples are that gravity is finely tuned to within 1 in 10^40 and the cosmological constant that governs the universe’s expansion rate is fine-tuned to within 1 in 10^120. If either of these varied by the tiniest margin then life of any kind would be impossible.  Groothius states, “the likelihood of this constant occurring by chance is that of randomly hurling a dart from outer space and hitting a bull’s eye on earth that is less than the size of one atom.” [3]

William Lane Craig chimes in with the so-called weak force, one of the four fundamental forces of nature and operates inside the atoms’ nucleus.[4] This force is finely tuned to within 1 in 10^100 to allow life to exist. Craig reports, “scientists used to think that whatever the very early universe might have been like, given sufficient time and some luck, intelligent life forms like ourselves would eventually evolve somewhere. As a result of discoveries over the last forty years or so, we now know that assumption was wrong. In fact, quite the opposite is true.” [5] There are many other finely-tuned constants and quantities, but I’m sure you get the point. A life-permitting universe is radically less probable than a life prohibiting one.

What’s this got to do with God?

There are basically three options to explain fine-tuning, the universe had to be this way, it happened to be this way, or it was made to be this way. Now there doesn’t seem to be any reason it had to be this way. It certainly seems possible that these values could have been different. If they had to be this way, then it would be impossible that they could have been different, which we don’t have any reason to believe. As we have seen above, the happened to be this way option doesn’t seem to fare any better. Craig puts it best when he says, “The fundamental problem [with chance] is that the chances that the universe that exists should happen to be life-permitting are so remote that this alternative becomes unreasonable.” [6]

We infer by process of elimination that the universe was made to be this way. In other words, our universe had a designer that designed it to be life-permitting. He planned out the constants and quantities so that the universe could sustain life.

This doesn’t prove that God exists. As we said above, there is a chance that the values just randomly fell within life-permitting ranges. We aren’t saying that God’s existence is proven, but rather that fine-tuning gives us good reason to think that he does. As Robin Collins puts it, “All these features of the laws of nature, let alone the fact that our best theories seem to require that the universe has a beginning, give the impression in many people’s minds that the universe was created by some transcendent intelligence.” [7] It seems we have at least one reason in fine-tuning to believe that God exists. 

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[1] William Lane Craig, On Guard: Defending Your Faith with Reason and Precision – Kindle (Colorado Springs: David C. Cook), Ch 5.

[2] Douglas Groothuis, Christian Apologetics: A Comprehensive Case for Biblical Faith – Kindle (Downers Grove: InterVarsity Press, 2011), Ch 12.

[3] ibid.

[4] William Lane Craig, On Guard: Defending Your Faith with Reason and Precision – Kindle (Colorado Springs: David C. Cook), Ch 5.

[5] ibid.

[6] ibid.

[7] Robin Collins, The Teleological Argument in Philosophy of Religion: Classic and Contemporary Issues, edited by Paul Copan and Chad Meister (Malden: Blackwell Publishing, 2008), pg 102.


8 thoughts on “If you believe in gravity, you should believe in God.

  1. Definitely agree. It’s hard to look at a world so grand and immense with such complexity and think that it just happened over time when in time all I see is destruction or the second law of thermodynamics. Doesn’t mean what I see still isn’t an outlier. Good writing bro!

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