Greg and Amy answer a question about why we should think God, rather than other explanations people offer, is the best explanation for the existence of the universe.
Question: Many people believe the universe didn’t come from nothing, but [from] an unknown theoretical, naturalistic, or mythical cause. Why is the Christian God logically necessary in light of endless other explanations that try to fill the same blank?
Greg: Given the origin of the universe—given that there was no universe, and then there was a universe—we’re talking about standard Big Bang cosmology, and there is a tremendous amount of observational, astronomical evidence for that and evidence in general relativity and in special relativity. So, this is theoretical physics and philosophy.
There’s a range of arguments in favor of the universe coming into existence. There’ve been attempts to find or to exploit what Stephen Meyer has called a quantum loophole, where you make a jump to quantum physics. I think Krauss does this in his book A Universe From Nothing and argues that certain mathematical things can be in place that then have an effect of causing the universe. The problem is, mathematics are abstract, and abstract entities have no causal power, and also, abstract entities arguably exist in a mind. So, even if you are arguing from math, you still have no material world. You have math as abstract entities that are not active, but rather inert, and you have a mind that holds the abstract entity—so, a non-physical mind. And that’s precisely what they’re trying to avoid. So, I don’t think that solves any problems.
There are all kinds of models that are being offered as a way of explaining the universe without resorting to a divine mind as the responsible cause. And there’s some other important work by Borde, Guth, and Vilenkin—it’s called the BGV theorem—that says any universe that is expanding, no matter how you conceptualize it, had to have an absolute beginning. So, the evidence—the actual evidence for an actual beginning, an absolute beginning of our universe—is very, very strong, even though there are many cosmologists who don’t yet want to acknowledge it, and I think Alan Guth thinks we have an eternal universe. I don’t know how he solves the problem of the second law of thermodynamics, which is really a significant issue, but nevertheless, most of them say we don’t know. But the evidence that we have right now from those three areas—astronomical, theoretical physics, and philosophical—points to an absolute beginning.
Now, with an absolute beginning in place, now you ask the question, what is the cause of the absolute beginning? And you have one of two options, generally speaking. So, now I’m working in metaphysical categories. The first one that I’m using is the metaphysical category of cause and effect. Cause and effect is not a scientific category, because cause and effect cannot be empirically determined or seen, as it were, and David Hume made a huge deal about this. He was a radical empiricist. It’s not something physical. That effects need causes adequate to the effect is a metaphysical principle that all of science depends on. Why did this effect take place? What is the cause that’s adequate to it? So, I’m drawing from that, and I’m also drawing from the law of excluded middle. Either A or non-A. Either caused or not caused. Those are your only options.
Now, if you want to say the universe came into existence with no cause, then that’s an option. To me it’s not the intuitive option. It’s not the obvious option. It’s not where the smart money is, because we have a principle of causality that is very well established, and science depends upon it. If you want to go and say, “Well, we know that in the physical world, but we don’t know that in a non-physical world,” and that’s treating causality as a physical, scientific, empirical principle. It is not, as David Hume has pointed out. It is a metaphysical principle. So then, I just simply ask the question if it’s caused—and that makes the most sense—what kind of cause would be adequate to the effect? And this is also a metaphysical principle that is employed by science all the time.
I give an illustration sometimes. I was in a hotel in Poland, and there was a big—there was an explosion. It was actually a tire that exploded that somebody had been pumping up. It shocked everybody, and everybody’s thinking, “What caused that? What was that? What caused it?” Now, if I said a pin dropped on the carpet, no one would accept it, because that is not an adequate cause for the effect. So, then, we ask ourselves the question, what kind of cause is adequate to create the material universe as we know, that runs according to a certain set of uniform principles—natural laws? Well, it’s going to have to be an agent because only an agent can initiate the cause. It can’t be physical or material in any sense because the material universe is the effect. When you start asking these questions, it’d have to be pretty powerful, pretty smart, etc, etc. That seems obvious. These are the kinds of characteristics that describe the God that Christians defend in classical theism.
Now, if that’s not the answer, and something caused it, you’re going to have to come up with a different cause that is adequate to the effect. That’s all. Those are the logical categories that people are stuck with. I’m not saying God had to cause it. What I’m saying is he is the most likely candidate. That’s where the smart money is. Someone like God. That’s the cosmological argument—actually, the form of the cosmological argument called the kalam cosmological argument.
Some people don’t think it goes through, but then you ask them, why doesn’t it go through? “Well, we’re working on models to show....” Well, you can work on models all day long. All models are conjectures, and the problem with a lot of these models is they don’t work, and the contemporaries of those who are making the models are pointing out this isn’t going to work. Let’s try something else. So, as long as they’re working with models, models aren’t evidence. Models are conjectures.
Here’s what we know. We have good reason to believe there was an absolute beginning to the universe because of logical categories. Either the universe was caused or uncaused. Caused seems to be the most sensible option. Then we have to ask ourselves, what kind of cause would be adequate to the effect? And we have one. We can reason to that cause, and then, lo and behold, that cause fits the profile of the God of classical theism. So, there’s nothing amiss here with drawing the conclusion that the God of classical theism is the cause of the universe. All the pieces fit together, even though I’m not claiming it’s an absolute proof. I’m just saying, the smart money is on this option.
Amy: You said an agent—immaterial, powerful, smart—and I would also add to that, moral, because we also see, just by looking around, the existence of an objective morality, and there are probably other things too, I think, if we thought about it, we might be able to bring into this. My point is just that there are other aspects of reality that can come into play here, besides just that one thing about the beginning of the universe.
Greg: The God we’re talking about has additional explanatory power, or, I should say, provides additional explanatory power for other features of the universe, like the order of the universe—that’s teleology—like the morality of the universe—if a person is going to acknowledge objective morality, which, in my view, is absolutely secured by the problem of evil. If there is a problem of evil, there can only be so if there’s objective morality. Relativism cannot produce a genuine problem of evil. Anyway, so those are other things that get explained with this explanation of the origin of the universe. The cosmological question.
Amy: And then, I wanted to specifically note—the immaterial, powerful, smart agent—this rules out the idea of a force, like a natural law of some kind, or even a supernatural force that’s not a personal agent that doesn’t cause things. It rules out a natural cause, and it rules out no cause. So, there are a lot of things that people propose as an answer to the beginning of the universe that are ruled out by these other conclusions that come from the argument.
Greg: And what I want people to see here, too, is this is not God-of-the-gaps. I’m not just making these things up. This is a very careful process of reasoning that, apart from the empiricism of the scientific method, is very consistent with the kind of thing the scientific enterprise probably produces. It looks at an effect and asks the question, what caused that? It presumes causality. And part of the question has to do with the adequacy of the cause suggested to create the effect in question. There’s nothing tricky about this.
Amy: Then, the final thing I want to note—because the question asked why the Christian God is logically necessary—I will also say, I don’t think we can narrow down as far as the specifically Christian God, necessarily. I think there are other arguments that can do that, obviously, but if you’re just looking at the origin of the universe, there are other monotheistic options out there.
Greg: That’s right, and there are going to be some people that argue for the logical necessity of God, but that’s not the case we’re making. What we’re trying to do is use abductive reasoning. It’s an inference to the best explanation. That’s all we’re doing. And this is a completely legitimate way of knowing. Is it empirical? No. This question can’t be answered empirically. We are outside of empiricism. But why is that a liability? There are all kinds of questions we can’t answer empirically. I can’t know what I had for dinner three nights ago by the empirical method. I know it through a different method: my direct awareness of what I ate and my memory of such. And, in fact, we can know things by authority. That’s another means that we individually know things. And I’m not talking about the Bible. Every time we cite scientists, we’re citing an authority we think is credible. So, there are lots of ways of knowing things outside of just empiricism, and empiricism itself has real liabilities, because if you say empiricism is the only way to know something for sure, like science, that statement itself cannot be proven as knowledge or be demonstrated to be knowledge according to empirical methods. It’s self-refuting, along with scientism and verificationism, which are other concepts that are related to this problem.