Gottfried Wilhelm Leibniz was a German philosopher, mathematician, a metaphysician and an expert in logic who is recognized for his independent invention of the differential and integral calculus (imagine being able to include “I invented calculus” on your resume)! To put it bluntly, Leibniz was a smart dude!
While it is impressive to be able to “invent calculus,” in my opinion, the cherry on top of all of his accomplishments was his work in the field of apologetics. In fact, Leibniz crafted his own logically deductive argument for the existence of God. His case is so powerful that it is still being presented and debated in academia today by philosophers such as William Lane Craig.
Needless to say, just as calculus is still going strong, so is Leibniz’s argument for God’s existence!
Some refer to his case as “The Argument from Contingency,” but it is most commonly known as “The Leibnizian Cosmological Argument.” Consider the deep thoughts of Leibniz one step at a time:
1- Everything that exists has an explanation of its existence — either in the necessity of its own nature or in an external cause.
2- If the universe has an explanation of its existence, that explanation is God.
3- The universe exists.
4- Therefore, the explanation of the universe’s existence is God.
The fourth step of the argument is a deductive conclusion that follows logically if the three premises are true. Moreover, this also means that if the three premises are merely probably true, then one is completely rational in affirming the final conclusion. So, the question is raised: are the premises true or probably true?
Surely, no reasonable person will deny the third premise! Of course, some might argue that the universe does not exist exactly as it appears to exist, but they still affirm that the universe exists in some form or fashion. Perhaps one thinks the universe is not composed of matter and we live in a digital reality like the Matrix, but then, the Matrix would be the universe and the Matrix exists. So, premise (3) is virtually undeniable.
What about the first premise? Is it true or probably true?
Some committed atheists contend that while this is true of everything else, the universe is different. They go on to deny this first premise by saying things like, “the universe just exists without an explanation and there is no explanation needed!”
Hiking Trips & Unreasonable Buddies
William Lane Craig offers a fantastic thought experiment demonstrating the absurdity of such a response. Imagine that you are on a hiking trip in the Colorado Rocky Mountains with a friend who happens to be a scientist. While on your journey you look at the trees, the rushing river, and the mountain peaks. You survey the boulders along the trail, the chipmunks scurrying by your hiking boots, and the birds soaring high above. You marvel at the mist in the air and the colorful rainbows stretched throughout the canvas of the sky. You feel the warmth of the sunlight on your face as it shines through breaks in the clouds.
Your hiking buddy is a scientist and can provide an explanation to everything you observe and empirically experience through your five senses. You are grateful for your scientifically-minded friend and you love learning from him.
But then, out of the corner of your eye, you spot a translucent and shiny spherical object (the size of a volleyball) similar to the Palantír “crystal ball” in the Lord of the Rings, but also unlike anything you have ever seen or imagined! You are enthralled by its majesty and you look forward to hearing your friend provide an explanation as to why this mesmerizing spherical object exists.
To your surprise, your hiking buddy suddenly changes his tune. He says, “Oh don’t worry about that stupid round thing; it just exists inexplicably!”
When you press him as to why he seeks to find — and loves to share — explanations for everything else that exists, but dismisses an explanation for the shiny sphere, he provides nothing but arbitrary words. He simply asserts, without any reason at all: “That’s the one thing that does NOT have an explanation of its existence so stop asking about it. Just ignore it and let’s keep hiking!”
When you realize he is opposed to the sphere having an explanation because it would destroy his assumed worldview, it is easy to see that his response is guilty of what has come to be known as “the Taxi Cab Fallacy.” This logical error occurs when one hops in the “taxi-cab” and assumes a certain worldview attempting to make particular points but then jumps out of the system of thought when it goes against a certain presupposition they blindly support. In this case, the hiking buddy seems to be assuming that everything that exists always has an explanation — except for the one thing that would destroy his worldview of atheism. Thus, he dives out of the taxi-cab before reaching its logical destination. You know his response is insufficient. Not only is it arbitrary, it is given without any reason at all; thus, it is unreasonable.
One might contend that the universe is exempt from the first premise of Leibniz’s argument because it is so unfathomably huge! However, size does not matter? Consider the shiny sphere once again. I noted that it was approximately the size of a volleyball in the thought experiment. It is insufficient to arbitrarily assert that everything has an explanation of its existence except for shiny crystal ball type things that are roughly the size of a volleyball. Well, if that is not a valid response, does anything change if the size of the shiny sphere is increased to the size of a basketball? What about the size of a sphere comparable to that of a car, a house, a small moon, a Death Star, a planet, or a galaxy?
No, just because the size of a thing gets bigger, and bigger, there is no reason to suddenly think that an explanation is no longer required once it reaches a certain size. From this it follows that if the sphere were increased to the size of the universe, it still demands an explanation. This is true not only of things the size of our universe, but it is true of the universe itself. There must be an explanation as to WHY it exists.
Both the third and the first premise of Leiniz’s argument seem to stand strong. But what about the second step of the argument? Why think that if the universe has an explanation of its existence then the explanation must be God? And if it is not acceptable for the universe to just exist inexplicably, then is God not going to run into the same problem? The answer is found in the important distinction offered in the first premise between things that exist contingently and things that exist necessarily.
If X exists necessarily, then it is impossible for X not to exist.
Possible examples of necessarily existing things would include mathematical objects, the laws of logic, and other abstract objects. Philosophers discuss and debate whether abstract objects exist or not, but the fact remains that if things like numbers actually exist, then these would be an example of something that exists necessarily. Contingently existing things, on the other hand, can fail to exist, do not have to exist, and they depend on other things for their existence.
The universe seems to be a contingent thing. After all, science demonstrates that the universe has not always existed. That is to say, a state of affairs was such that the universe did not exist, but now it does. Thus, it seems that the universe has failed to exist in the past, and thus, is not a necessary entity. If time and space are contingent, then all of the contents of this spacetime universe seem to be contingent as well. The only explanation of the existence of a contingent spacetime universe is that space and time rest on a non-contingent entity. This being would have to be something that cannot NOT exist, because of the necessity of its own nature. It would exist no matter what.
Why Is God the Answer?
To answer this question we must focus on the universe! That is to say, what exactly is the universe? The universe is everything nature! Science is the study of nature, so the universe is all things that are potentially tested or discovered scientifically. It is everything in space and time, all matter, physical reality, and all energy. In a nutshell, the universe is everything nature, time, and space.
If the contingent universe is everything nature, time, and space, then it makes no sense to say that nature, time, and space are contingent upon anything found in nature, time, or space. So what remains? Two live options are currently on the table:
1- An unembodied mind (like a soul)
2- Abstract objects
Some atheists and agnostics who are committed to a so-called “lack of belief” in the existence of God have offered abstract objects as the necessary “thing” that the universe is contingent upon. For example, Stephen Hawking suggested that the universe is contingent upon the abstract law of gravity (he unwittingly denied physicalism) and Alexander Vilenkin appeals to these supernatural, immaterial, non-physical abstract “platonic” objects as well. With all due respect, although these men are brilliant scientists, they seem to be poor philosophers. I am happy to see these men reject a purely physical view of the universe, but if one is willing to be open to immaterial realities like abstract objects, why not an immaterial God? Moreover, if these scientists would have had training in the field of philosophy they would know that abstract objects — by definition — do not cause things. Thus, it is hard to see how something could be contingent upon another thing that is causally effete. A better explanation is needed. Fortunately, we have another option — an unembodied mind, like God!
If God exists as an omnipotent and omniscient immaterial and unembodied mind, then He would be both necessary and the kind of thing that could cause things. God would be the necessary being supporting all contingent reality (just as Colossians 1:16 suggests):
For by him all things were created, in heaven and on earth, visible and invisible, whether thrones or dominions or rulers or authorities—all things were created through him and for him.
However, if for some (emotional?) reason you do not like the word “God,” you can always refer to the necessary being in which the contingent spacetime universe is grounded as the enormously powerful, uncaused, necessarily existing, immaterial, and eternal mind (and thus a personal being) who created the entire spacetime universe and all of its contents.
I don’t know about you, but I think it is much easier just to say… GOD!
Stay reasonable (Isaiah 1:18),