The kalam argument seeks to establish the existence of God based on how things need an external cause in order to come into existence. In short, we are seeking to understand what is eternal. Is everything eternal? Or are only some things (or, possibly only one thing) eternal? Unlike the contingency argument, which can refer only to concurrent causes of things, the Kalam argument specifically looks at things which come into existence from a state of non-existence. From there, the Kalam argument finds an adequate, necessary explanation in an eternally existing, uncaused and divine Creator. In this form of the argument, we’ll use conclusions from modern physics as well as from philosophy to establish that the universe has a beginning, and go from there.
How Can Anything Come Into Existence?
There are only three possible options to explain how anything comes into existence. Things are caused to exist either by: 1) themselves, 2) something else, or 3) nothing.
Option one is clearly absurd: for something would have to pre-exist itself in order to cause itself; in which case it wouldn’t need a cause — it would just already exist.
Option three is also unacceptable, since “nothing comes from nothing.” Nothing is the absence of anything. And nothing—being nothing—has no ability to cause anything. Besides, if things could pop into being out of nothing, why doesn’t this happen frequently? Why is it that an elephant doesn’t suddenly appear in the middle of your conversations? The most reasonable explanation for things not coming into existence from nothing frequently, is simply because “nothing comes from nothing.”
This leaves us with option two: for anything which begins to exist, something else must act as the cause of its coming into existence. In short, anything which begins to exist must have a cause external to itself.
The Universe’s Ticking Clock: Science
Now, here is an interesting observation. The best of scientific knowledge currently points to an absolute beginning of the physical universe — specifically, some 13.8 billion years ago when all of space, time, matter and energy essentially “winked” into existence from no prior state of physical affairs.[1]
Furthermore, the second law of thermodynamics suggests an absolute beginning to space-time reality. If usable energy is running down (which, the second law of thermodynamics says it is), and has not yet run down completely, this means the universe couldn’t have been “running” forever into the past.[2] To say otherwise means our universe would already be experiencing the predicted thermodynamic “heat death.” But, our universe isn’t currently experiencing thermodynamic heat death. So our universe could not have been running infinitely into the past.
To put it another way, if our universe is on an “energy time-limit” and has been existing for an infinite amount of time, that time-limit would have already expired — which it hasn’t. So our universe could not have been running forever into the past.
In short, modern cosmology strongly suggests physical reality had an absolute beginning. That the universe began to exist.
The Universe’s Ticking Clock: Philosophy
But also, the notion of an infinite, backwards series of physical causes seems philosophically—and not just scientifically—untenable. For example: If someone told you they just finished counting down from (or to) infinity, you’d be skeptical of this claim. You might believe they finished counting down from (or to) some very large number, but you’d rightfully object to the idea they finished counting down from (or to) infinity. Because how is that possible? The counting would have to have no beginning. But, if there was no beginning, only an infinite series of counting, then no part of the series could ever arrive in time, because before that part of the series of counting, there would be an infinite series of counting before it.
A similar notion applies if we’re to believe the physical universe is eternal into the past—since the fact we’ve arrived at today would imply we’ve somehow finished “counting down from infinity.” But that can’t be. So, there must have been an absolute, temporal beginning to space-time reality to explain how we’ve arrived at this current point.
So, both scientific evidence and philosophical argument strongly suggest that the universe (space-time reality) had an absolute beginning. But if this is the case—and if it is also the case that whatever begins to exist has a cause external to it—then the universe (all of physical reality) must itself have a cause external to it.
External Cause of the Universe: God
But whatever caused the universe cannot be another physical thing, since whatever brought all of space, time, matter and energy into existence must transcend these created realities. Therefore, we can firmly conclude the existence of a timeless, space-less, immaterial, and (obviously) extremely powerful creator of the physical, space-time realm.
Furthermore, this creator must be essentially a mind (or mind-like), since the only other possible option for an immaterial reality would be an abstract object, like the number seven. But abstract objects (if they exist apart from minds to begin with, which arguably they do not) can’t do—or cause—anything; such is the nature of being “abstract.” We are left, then, with just one option: an immaterial, timeless, space-less, eternal and extremely powerful mind which caused physical reality to exist. To most people, that sounds a lot like God.
Example Dialogue
Now that we’ve heard the argument, let’s see what it might look like in a real-life conversation.
Evangelist stands near a street corner with rosaries in hand. He smiles and says hello to passerby.
Evangelist: Would you like a rosary?
Passerby: Sure. These are prayer beads, right? [takes the rosary and looks at it]
Evangelist [E]: Yes, that’s right. They are a physical way to pray, as you move your fingers along each bead with certain prayers. It really helps to focus the mind.
Passerby [P]: Well, I can definitely use the help with focus, but I’m an atheist so I wouldn’t get much use out of these [P begins to hand back the rosary].
E: [E shakes his head] Oh please, you keep them. I can give you some information on how to use them, if you’d like [E gives P a pamphlet on how to pray the rosary]. I would like to ask, is there a time in your life that you ever did believe in God or a higher power?
P: Sure, I had some belief in God when I was a kid, but once I started learning more about science, there didn’t seem to be any compatibility between science and religion, and I can’t choose faith over reason.
E: [E nods understandingly] The way most people talk about faith, it would seem you have to make that choice, and of course, as an intelligent person, you’d choose reason; but actually, you can have both faith and reason. Do you mind if I offer you one good reason why I believe in God?
P: Sure, but I have to admit, I don’t think faith and reason work together. I mean, how can that be possible? What about, like, evolution or the Big Bang Theory?
E: Funny, but I was just about to get into that very question as part of my reason to believe in God. Did you know that a Catholic priest and scientist actually formulated the Big Bang Theory?
P: [shakes his head] No, I hadn’t.
E: Yeah, his name was Fr. George Lemaître, and he also convinced Einstein of the Big Ban theory. Later, Einstein admitted it was the most beautiful theory of the universe he ever encountered. Anyway, the beginning of the universe, as the Big Bang Theory describes it, seems to speak in favor of God; or at least many people think so.
P: And why’s that?
E: Mostly for the simple reason that when things begin to exist, they must have some external cause. Things don’t pop into being from nothing, after all.
P: That’s interesting, but why should we think God is the cause of the universe?
E: We should clarify what we mean by “God” as well as the “universe.”
P: Sure.
E: Let’s start with the universe, then. I think we can identify the universe simply as the collection of all space, time, matter, and energy. In fact, what modern Big Bang cosmology predicts is that all physical reality essentially “winked” into existence some 13.8 billion years ago. Now, since nothing can be the cause of itself, then whatever caused all of space, time, matter, and energy, must transcend these caused physical realities. If this is true, then we are left with two possible options for what caused the universe. The first is abstract objects, such as propositions or the number seven. The second is an immaterial mind. Now, many philosophers would argue that abstract objects only exist in minds and don’t exist beyond our thinking about them, but even if that isn’t the case, abstract objects are surely incapable of acting as concrete causes of things; after all, that is simply what it means to be abstract: literally, “pulled away” from concrete reality. Therefore, we’re left with only one option: the existence of an immaterial mind which caused all of physical reality to exist.
P: And this is God, because…?
E: I think we consider this being God because whatever else God is supposed to be, God is supposed to be the ultimate cause of everything else. Plus, most religions attribute intelligence and power to God, and so far we’ve reached a creator that is both intelligent and extremely powerful. Admittedly, there’s a lot more we’d like to know about God, but this argument seems to produce a fairly robust conception of a divine creator of the universe, which I think is pretty cool!
P: OK, but then wouldn’t God also need a cause?
E: It’s not necessary, because the argument doesn’t say “everything” has to have a cause. The argument only says that “anything which begins to exist” has a cause. And since time is something that began to exist, time itself requires a cause. But whatever created time would be itself timeless and, therefore, eternal. But to say something is eternal is just to say that it never began to exist, and so that something—in this case, God—would not only not have a cause, but also couldn’t have a cause! To suggest otherwise would be like asking, “What caused an uncaused being?” and that just doesn’t make sense.
P: Fair enough, but this argument is still a long way from proving Christianity. Maybe this God just made the universe and walked away. Why do you think He cares about us?
E: That’s a fair observation and question. But they lead into a discussion that is separate than our discussion on the existence of God. For now, it might be possible to link the two discussions by saying that arriving at God’s existence by philosophical argument is a powerful conclusion. Certainly, this conclusion changes how we should look at the world, including religion. Because if we have prior, independent reason to think that God exists, then possibly some religion is true. While this argument doesn’t prove Christianity, it does prove the possibility of Christiantity, and offers a conception of God that seems perfectly compatible with it. So, I guess the next step would be to see if there are any other arguments that we could layer on top to advance the case from God to Christianity—which I think there are!
P: Like what?
E: Well, I think there are moral and historical arguments that are just as helpful, and continue to narrow the “theological hunt,” so to speak. Would you be open to hearing some of these, or possibly taking some reading material?
P: Sure, I don’t suppose it could hurt to read more into this.
E: That’s great. And honestly, I really appreciate you taking such a reasonable look into religion. Obviously, I agree that if something goes against reason, we should be skeptical of it. At the same time, I also believe the Catholic faith offers a great “both/and” approach to faith and reason. Here’s some material I think you’ll enjoy reading on the subject [hands out material].
Conclusion
So, that’s the Kalam argument. It is a powerful conversational tool for two reasons: the argument is easy to memorize with its three steps (everything that begins to exist has a cause; the universe began to exist; therefore, the universe has a cause), and the argument shows a deep compatibility between modern science and the existence of God.
[1] Dr. Stephen Barr, Modern Physics, the Beginning and Creation (Washington, DC: Washington Theological Consortium, 2013) <https://washtheocon.org/wp-content/uploads/2013/12/Modern-Physics.pdf>.
[2] For some definitions of the second law of thermodynamics, see <https://web.mit.edu/16.unified/www/FALL/thermodynamics/notes/node37.html>.