Could the Universe Be Eternal?
One of my favorite arguments for God’s existence is the Kalam Cosmological Argument. While this argument has historical roots, contemporary Christian philosopher William Lane Craig has popularized it more recently. The argument goes like this:
- Everything that begins to exist has a cause.
- The universe began to exist.
- Therefore, the universe has a cause.
This is a logically airtight argument. That is, if we can demonstrate that both premise (1) and (2) are true, the conclusion (3) necessarily follows as true. Let’s consider the premises in turn.
(1) EVERYTHING THAT BEGINS TO EXIST HAS A CAUSE.
This first premise seems intuitively obvious. To reject it, one would have to posit that something can come from nothing. But that view has to be the height of absurdity. Nothing can’t produce anything. After all, our own experiences and scientific observations tell us that things just don’t pop into existence uncaused. None of us, for example, have ever experienced a new Corvette popping into existence in our driveways, as nice as that would be. Additionally, if things can pop into existence uncaused, then it remains inexplicable as to why this doesn’t happen all the time.
As one might imagine, most embrace this premise, although a few have sought to refute it over the years. Quentin Smith, for example, suggests that “the most reasonable belief is that we came from nothing, by nothing, and for nothing.”1 But I must confess, I’m not sure I understand how this is possible. How did we come from nothing? How did nothing have the capability of causing anything at all?
If prior to the existence of the universe, nothing existed – including space, time, matter, or God – how did the universe come to be? People, like Quentin Smith, must violate everything we know about the cause and effect relationship in our universe to adopt this position. Even the great skeptic David Hume once remarked, “I never asserted so absurd a proposition as that anything might arise without a cause.”2
To get around this metaphysical impossibility, skeptic Lawrence Krauss suggests that the universe came into being from nothing. But then he goes on to explain that “nothing” is really a quantum vacuum of fluctuating energy. And as many have already pointed out, Krauss equivocates on the word nothing. After all, a quantum vacuum of fluctuating energy isn’t no-thing. It’s something. One still needs to explain how this vacuum came to be.
Additionally, others have adopted the position that premise (1) is true for all things inside the universe, but it’s not necessarily true of the universe itself. The problem with this view is that it commits the taxicab fallacy. That is to say, it adopts the standard cause and effect principle when it’s convenient, but then hops off — like one would a taxi — once it gets to its desired destination. Not only is this view logically inconsistent, it assumes that the causal principle is only true of the material world. But the cause and effect principle is a metaphysical principle, in that it’s true for all reality. Being cannot come from nonbeing.
Finally, the last objection to premise (1) usually comes in the form of a question: “Who caused God?” But this misunderstands the premise. For the premise doesn’t state that “whatever exists has a cause.” Rather it states that “whatever begins to exist has a cause.” And theists have maintained, that God has never had a beginning. He exists eternally by necessity. If he doesn’t, then he’s not God. This is what we mean when we say “God.” If he owes his existence to an external cause, that external cause would be God. So asking the question, “who caused God?” doesn’t help the skeptic get around premise (1). Theists have maintained for millennia now, that God is necessarily eternal. And to ask, “what caused him?” misunderstands our position.
(2) THE UNIVERSE BEGAN TO EXIST.
Since it’s difficult to disprove premise (1), many skeptics set their sights on premise (2) which asserts that the universe began to exist. In a previous post, I laid out scientific evidence which suggests the universe is not eternal. In this post, however, I want to focus on the philosophical reasons for rejecting a past-eternal universe.
To get around premise (2), the skeptic must maintain that the physical universe has existed for all eternity and has thus existed for an infinite number of moments. However, while we use infinity in mathematical or theoretical worlds, infinity in reality is impossible as it results in all sorts of logical absurdities.
Think, for example, about a meter stick that you divide in halves forever. Could you divide the meter stick in half an infinite number of times? How do you know the point at which you cross the threshold of a natural number to infinity? And if you reach infinity, isn’t it true that you could subdivide the meter stick one more time?
Perhaps the most famous example demonstrating the absurdity of infinity in reality is David Hilbert’s thought experiment — Hilbert’s Hotel. Hilbert told us to imagine a hotel with an infinite number of rooms. Additionally, he said to imagine that all the rooms are occupied so that not a single room is vacant. Now, suppose a guest comes to the check-in desk and asks for a room. The manager says, “yes, of course you can have a room.” He then proceeds to move the person in room #1 to room #2, and the person in room #2 to room #3, and the person in room #3 to room #4, and so forth to infinity. He then takes the new guest and places them in the vacant room #1. But remember, before the guest showed up, the infinite number of rooms were already occupied.
Now, Hilbert says to suppose an infinite number of guests show up to a fully occupied hotel asking for a room. “Of course, the manager says.” He then proceeds to move the person in room #1 to room #2, and the person in room #2 to room #4, and the person in room #3 to room #6, and so forth to infinity, always putting the previous occupants in a room number twice their original one. Because all the former occupants now reside in even numbered rooms, the infinite number of new guests all go into the odd numbered rooms. Remember, though, before the infinite number of guests arrived, all the infinite number of rooms were occupied.
In the first example, we already had an infinite number of guests, but we were able to add one more. So, the equation would look something like this: infinity + 1 = infinity. In the second example, we had an infinite number of guests already staying in the hotel before adding another infinite number of guests. This equation would look like this: infinity + infinity = infinity. Despite adding a different amount to infinity in both equations, we still ended up with the same sum of infinity. The mathematical impossibility of such a hotel demonstrates the absurdity of an actual infinity in reality.
Consider another example. The medieval philosopher al-Ghazali asks us to imagine both Jupiter and Saturn orbiting the sun from eternity past. If for every time Saturn orbits the sun, Jupiter orbits it 2.5 times, which planet has orbited the sun more times? Well, if both planets have been orbiting from eternity past, the answer is that they’ve both orbited the sun the same amount — infinity. But doesn’t that seem absurd? In fact, we know that the higher the number of orbits, the greater the discrepancy that exists between the two. But if Saturn has orbited an infinite number of times, even though Jupiter has been orbiting 2.5 times for every Saturn orbit, they’ve both orbited the sun the same amount.
These illustrations help demonstrate that an actual infinite number in reality is impossible. And if an actual infinity is impossible, the universe could not exist for an infinite number of moments.
These absurdities raise another significant problem for the person who wants to reject premise (2). And that problem is that it’s impossible to traverse the infinite. Put another way, if the universe has existed for an infinite number of days, we could never arrive at today because that would mean infinity came to an end. But infinity can’t come to an end. That’s what it means to be infinity.
Or think about it another way. Before we can arrive at today, yesterday would have to occur, and the day before that, and the day before that, and so on to infinity. But how does one know when we’ve reached infinity in the past? There’s no point at which we could start counting the days backwards to today. That would be like counting all the negative numbers from infinity back to zero.
Interestingly, many skeptics acknowledge our universe isn’t past eternal based on the scientific evidence. A lot of these same skeptics, however, attempt to get around this problem by suggesting an eternal multiverse. But the absurdity of infinity still applies to a multiverse. It’s impossible to traverse an infinite number of points in any physical universe, even one beyond our ability to detect. So, the skeptic still faces the same problem.
In sum, since it’s absurd to suggest that the universe has existed for an infinite number of moments, the universe must have began to exist a finite time ago.
(3) THEREFORE, THE UNIVERSE HAS A CAUSE.
Since whatever begins to exist has a cause (1), and the universe began to exist (2), it follows necessarily that the universe has a cause (3). Based on this argument, what can we know about the nature of this cause?
First, whatever caused the universe must come from outside the universe itself. That is to say, it must transcend the natural world.
Meaning, this cause must be spaceless, timeless, and immaterial since space, time, and matter all came into existence at the beginning of the universe. Especially relevant to this argument is that the cause is timeless and, therefore, never had a beginning. Now, the skeptic might object that a past eternal cause faces the same dilemma of a past eternal universe. But he would be mistaken, because the cause of the universe exists outside of, or independent of, time. That is to say, this cause existed in a timeless state, and thus hasn’t traversed over an infinite number of points.
The cause must also be personal. We reach this conclusion based on the fact that there are only two possibilities for a spaceless, timeless, and immaterial entity — either an abstract object like a number, or an unembodied mind. But abstract objects don’t possess causal power. They can’t do anything. This leaves a conscious mind who made a free will choice to create as the best explanation.
Finally, based on the size and complexity of our universe, this spaceless, timeless, immaterial, personal being must be all-powerful and extremely intelligent. And this being is what theists refer to as God.