Initial Arguments:
A Defense of the Cosmological Argument for the Existence of God

William Lane Craig

I want to begin just by thanking the Philosophy Department for the free dinner, as well as the invitation to participate in tonight's forum!

During the last quarter century, a remarkable revolution has occurred in American philosophy. This change was so noteworthy that even the popular media observed it. In an article entitled "Modernizing the Case for God," published on April 7 of 1980, Time magazine commented,

In a quiet revolution in thought and argument that hardly anybody could have foreseen only two decades ago, God is making a comeback. Most intriguingly, this is happening, not among theologians or ordinary believers, but in the crisp intellectual circles of academic philosophers, where the consensus had long banished the Almighty from fruitful discourse.{1}

The article quotes Roderick Chisholm to the effect that the reason that atheism was so influential a generation ago is because the brightest philosophers were atheists. But today, Chisolm says, many of the brightest philosophers are theists, and they're using a tough–minded intellectualism in defense of that theism. Premiere among this new crop of philosophers stands Alvin Plantinga of the University of Notre Dame, a sort of latter–day Anselm, whom the late J. L. Mackie, perhaps one of the most prominent atheists of our day, has facetiously canonized as "St. Alvin." A few years ago, Plantinga gave a paper entitled, "Two Dozen or so Theistic Arguments," in which he laid out an impressive and very creative array of arguments for the existence of God.{2} Unfortunately, the conventional wisdom that Hume and Kant put a permanent end to theistic arguments still widely persists among undergraduate students in philosophy today. This conventional wisdom is simply rooted in ignorance, and the very fact that we’re having this debate here this evening, I think, is testimony to the fact that this question is still very much a live issue today.

What I'd like to do this evening is simply to present, in outline, one particular theistic argument that I find to be a sound and persuasive argument, the so–called kalam cosmological argument. This argument not only survives the objections of Hume and Kant, but, as I shall show, both Hume and Kant actually endorsed both of the premises of the argument. So I will simply go through the outline with you, commenting on each step.

HANDOUT: THE KALAM COSMOLOGICAL ARGUMENT 

1. Whatever begins to exist has a cause of 
   its existence.

2.The universe began to exist.
  2.1 Argument based on the impossibility of 
   an actual infinite:
    2.11 An actual infinite cannot exist.
    2.12 An infinite temporal regress of events 
      is an actual infinite.
    2.13 Therefore, an infinite temporal regress 
      of events cannot exist.
  2.2 Argument based on the impossibility of the 
      formation of an actual infinite by 
      successive addition:
    2.21 A collection formed by successive 
      addition cannot be actually infinite.
    2.22 The temporal series of past events is 
      a collection formed by successive addition.
    2.23 Therefore, the temporal series of past 
      events cannot be actually infinite.
  2.3 Confirmation based on the expansion of 
      the universe.
  2.4 Confirmation based on the thermodynamic 
      properties of the universe.

3. Therefore, the universe has a cause of its 
   existence.

4. If the universe has a cause of its existence, then 
   an uncaused, personal Creator of the universe exists, 
   who sans creation is beginningless, changeless, 
   immaterial, timeless, spaceless, and enormously 
   powerful and intelligent.
  4.1 Argument that the cause of the universe is a 
   personal Creator:
    4.11 The universe was brought into being either 
      by a mechanically operating set of necessary and 
      sufficient conditions or by a personal, free agent.
    4.12 The universe could not have been brought into 
      being by a mechanically operating set of necessary 
      and sufficient conditions.
    4.13 Therefore, the universe was brought into being 
      by a personal, free agent.
  4.2 Argument that the Creator sans creation 
      is uncaused, beginningless, changeless, immaterial, 
      timeless, spaceless, and enormously powerful and 
      intelligent:
    4.21 The Creator is uncaused.
      4.211 An infinite temporal regress of causes cannot 
        exist. (2.13, 2.23)
    4.22 The Creator is beginningless.
      4.221 Whatever is uncaused does not begin to 
        exist. (1)
    4.23 The Creator is changeless.
      4.231 An infinite temporal regress of changes 
        cannot exist. (2.13, 2.23)
    4.24 The Creator is immaterial.
      4.241 Whatever is material involves change on 
        the atomic and molecular levels, but the Creator 
        is changeless. (4.23)
    4.25 The Creator is timeless.
      4.251 In the complete absence of change, time does
        not exist, and the Creator is changeless. (4.23)
    4.26 The Creator is spaceless.
      4.261 Whatever is immaterial and timeless cannot 
        be spatial, and the Creator is immaterial and 
        timeless (4.24, 4.25)
    4.27 The Creator is enormously powerful.
      4.271 He brought the universe into being out of 
        nothing. (3)
    4.28 The Creator is enormously intelligent.
      4.281 The initial conditions of the universe 
        involve incomprehensible fine-tuning that points 
        to intelligent design.

5. Therefore, an uncaused, personal Creator of the 
   universe exists, who sans creation is "beginningless," 
   changeless, immaterial, timeless, spaceless, and 
   enormously powerful and intelligent.

 

The argument is really very simple and consists primarily of three steps. (1) Whatever begins to exist has a cause of its existence. (2) The universe began to exist. (3) Therefore, the universe has a cause of its existence. And then in premise (4) we conceptually unpack what some of the principal attributes would be of a cause of the universe's existence.

Now, with respect to premise (1), whatever begins to exist has a cause of its existence, I'm not going to say very much in defense of this premise this evening. I really don't think that it's necessary because the premise that whatever begins to exist must have a cause of its existence I think is so intuitively obvious that scarcely anybody could sincerely deny that it is false. In fact, David Hume himself agreed that this principle is true. In a letter to John Stewart dated February, 1754, Hume wrote, "But allow me to tell you that I never asserted so absurd a Proposition as that anything might arise without cause: I only maintain’d, that our Certainty of the Falshood of that Proposition proceeded neither from Intuition nor Demonstration; but from another Source."{3} Hume didn't think that you could prove the causal principle, but he certainly believed in it. In fact, he thought that the denial of that principle was simply absurd. Similarly, as is well known, Kant held the principle "Every event has a cause" to be a synthetic a priori principle; that is, it's an informative proposition characterized by both universality and necessity.{4} Only Kant’s implausible and perhaps incoherent restriction of the categories to phenomena alone prevented him from holding that this principle applied to reality. So, as I say, it seems to me that this first premise is intuitively obvious, and even detractors of theistic arguments such as Hume and Kant themselves admit it's true.

The more controversial premise is the second one: that the universe began to exist. And in support of this premise I present two philosophical arguments, and then two scientific confirmations of those arguments. The first philosophical argument, (2.1), is the argument based on the impossibility of an actual infinite, and it runs like this: (2.11) An actual infinite cannot exist. (2.12) An infinite temporal regress of the events is an actual infinite. (2.13) Therefore, an infinite temporal regress of events cannot exist.

Now in order to grasp this argument it's important to distinguish an actual infinite from a potential infinite. An actual infinite is a collection of things having a proper subset which has the same number of members as the original collection itself. An actual infinite is not like a potential infinite, which is a collection which is at every point in time finite but is growing toward infinity as a limit. My argument is simply that an actual infinite cannot exist. I do not deny the existence of a potential infinite.

Why do I hold to (2.11)? Well, very simply this: if you try to translate the idea of an actually infinite number of things into reality, you wind up with all sorts of absurdities and, in the end, logical contradictions. For example, what is infinity minus infinity? Well, mathematically you get self–contradictory answers, unless you impose some wholly arbitrary rules to prevent this. This shows that infinity is just an idea in your mind, not something that exists in reality. David Hilbert, who is perhaps the greatest mathematician of this century, states, "The infinite is nowhere to be found in reality. It neither exists in nature, nor provides a legitimate basis for rational thought…. The role that remains for the infinite to play is solely that of an idea."{5} So as I understand the actual infinite, it is simply a conceptual idea; it is not something that exists in reality. (2.12) says, an infinite temporal regress of events is an actual infinite. I think this is fairly obvious. If the universe never began to exist, then the number of past events is actually infinite. And therefore it follows: (2.13) that an infinite temporal regress of events cannot exist. Therefore, the temporal regress of events is finite and must have a beginning. Since the universe is not distinct from the temporal series of past events, it therefore follows that the universe began to exist.

The second philosophical argument is the argument based on the impossibility of the formation of an actual infinite by successive addition. This argument is independent of the first. It's claiming that even if an actual infinite can exist, it cannot be formed by successive addition. And this argument goes this way: (2.21) A collection formed by successive addition cannot be actually infinite. (2.22) The temporal series of past events is a collection formed by successive addition. (2.23) Therefore, the temporal series of past events cannot be actually infinite. The first step in the argument, a collection formed by successive addition cannot be actually infinite, is true by the very nature of infinity. You can never get to infinity by addition because you can always add one more. Sometimes this is called the impossibility of counting to infinity, or another way it's referred to is the impossibility of traversing the infinite. Now if the past were infinite, it would be as though someone had claimed to have just finished counting down all the negative numbers ending in "0," and surely this is absurd. If you can't count to infinity, how can you count down from infinity? If you can't traverse an infinite distance by running in one direction, how can you traverse it by simply turning around and running in the opposite direction?

Indeed, the idea that the past could be actually infinite is absurd. I think this is well illustrated by the Tristram Shandy paradox of Bertrand Russell. Russell imagines Tristram Shandy, a character in a novel by Sterne, who writes his autobiography so slowly that it takes him a year to write down the events of a single day. Russell says that if Tristram Shandy were to live forever, then his autobiography would be completed because there would be an infinite number of years and an infinite number of days, so that every day would be written about. It seems to me that this conclusion is incorrect because the future is a potential infinite only. Tristram Shandy would never arrive at actual infinity. The number of days and hence the number of years of his life would always be finite but potentially increasing toward infinity as a limit. But suppose we turn this story around and imagine that Tristram Shandy has been writing from eternity past. Then the number of years and the number of days would in fact be actually infinite, and you could say that Tristram Shandy would have completed his autobiography. But if you say that Tristram Shandy would have completed his autobiography, then the question arises: Why did he finish it today rather than yesterday, or the day before, or the day before that? By any time in the past, an infinite amount of time had already elapsed, so that if Tristram Shandy would finish his autobiography given infinite time, he should have already finished at any point in the finite past. But that means that no matter how far back in the past you regress, you will never find Tristram Shandy writing, which contradicts the hypothesis that he has been writing his autobiography from eternity. And thus the notion of an infinite past, it seems to me, is absurd.

That leads to the second premise, that a temporal series of past events is a collection formed by successive addition. Again, I think this point is obvious. The series of past events is a collection which has been formed by one event occurring after another, by successive addition. But that leads to the conclusion: therefore, the series of past events cannot be actually infinite. It must be finite, and the universe must have begun to exist.

Again, this argument was agreed to by both Hume and Kant. In his Enquiry, Chapter 12, Section II, paragraph 125, Hume writes, "An infinite number of real parts of time, passing in succession, and exhausted one after another, appears so evident a contradiction, that no man whose judgment is not corrupted, instead of being improved, by the sciences, would ever be able to admit of it."{6} Hume tries to elude what he calls the absurdities and contradictions of this by embracing a nominalist view of numbers and abstract objects. Now I’m very much in sympathy with that view, but clearly it does nothing to solve the problem of how a temporal series of real past events could have been formed by successive addition and yet be infinite. And, as is well known, Kant as well, in the thesis of his first antinomy concerning time, also endorses this argument. Kant writes,

If we assume that the world has no beginning in time, then up to every given moment an eternity has elapsed and there has passed away in the world an infinite series of successive states of things. Now the infinity of a series consists in the fact it can never be completed through successive synthesis. It thus follows that it is impossible for an infinite world–series to have passed away, and that a beginning of the world is therefore a necessary condition of the world's existence.{7}

And it can't be emphasized enough that, according to Kant, this is an undeniable requirement of reason. Reason forces you to that conclusion, on Kant's view. Of course, he also believed that reason forced you to adopt the antithesis as well, but I think that the argument for the antithesis is simply a faulty argument. It erroneously assumes that time necessarily precedes the beginning of the universe; but on a non–Newtonian relational view of time, time begins simultaneously with the first event. So there's simply no problem about when the universe would have begun to exist in the empty time prior to the beginning of the universe. So again, it seems to me that this argument is a forceful and persuasive argument, which both Hume and Kant, in effect, concede.

Now some people are suspicious of philosophical arguments for the beginning of the universe. They want to know if there is empirical evidence for this thesis. And in fact there is. I mention in (2.3), first, the confirmation based on the expansion of the universe. According to the standard Big Bang cosmological model, the universe is not infinite in the past, but began to exist at a point in the finite past about 15 billion years ago. Not only all matter and energy, but physical space and time, were created in that event, so that there is literally nothing prior to the origin of the universe. Paul Davies, in his article, "Space–time Singularities and Cosmology," says,

If we extrapolate this prediction to its extreme, we reach a point when all distances in the universe have shrunk to zero. An initial cosmological singularity therefore forms a past temporal extremity to the universe. We cannot continue physical reasoning, or even the concept of space–time, through such an extremity. For this reason, most cosmologists think of the initial singularity as the beginning of the universe. On this view, the Big Bang represents the creation event; the creation not only of all the matter and energy in the universe, but also of space–time itself.{8}

Now, of course, some theorists were unhappy with the notion that the universe began to exist from nothing, and alternative models have been proposed. But none of these has been tenable either empirically or philosophically. For example, the oscillating model, which says that the universe expands and contracts from eternity, is physically, observationally, and thermodynamically untenable. The vacuum fluctuation models, which hold that the universe emerged from a quantum vacuum by a fluctuation, are untenable because they predict a non–zero probability for a universe existing at every point in space–time in the quantum vacuum, so that given an eternal quantum vacuum, all of the space–time points would spawn universes, which would then collide and coalesce into an infinitely old universe, which contradicts observation. The quantum gravity models all depend on the use of "imaginary time" prior to 10–43 second after the Big Bang; these are simply non–physical solutions. They are non–realistic solutions. Once you convert the numbers back to real time, the singularity reappears. So the most plausible model of the origin of the universe remains the Big Bang model, which posits a creation out of nothing. And that goes to confirm premise (2) the universe began to exist.

In the interest of time I'm going to skip over (2.4), the confirmation based on thermodynamic properties of the universe, and go right to (3. 0): Therefore, the universe has a cause of its existence.

In (4. 0), I deduce some of the principal attributes of this cause: If the universe has a cause of its existence, then an uncaused personal Creator of the universe exists, who sans creation, is beginningless, changeless, immaterial, timeless, spaceless, and enormously powerful and intelligent. Let me just focus on the argument for the personality of the Creator.

(4. 11) The universe was brought into being either by a mechanically operating set of necessary and sufficient conditions or by a personal, free agent. Either it was a free agent or it was just a mechanical physical cause. (4. 12) The universe could not have been brought into being by a mechanically operating set of necessary and sufficient conditions. Why? Because if the necessary and sufficient conditions were present from eternity, the effect would also be present from eternity. It's impossible to explain how the sufficient conditions could exist timelessly or eternally and not also have the effect equally co–present. The only way that a temporal effect could arise from an eternal cause is if the cause is a free, personal agent who is able to freely create the universe without antecedent determining conditions. And therefore it follows: (4. 13) The universe was brought into being by a personal, free agent.

And then on the rest of the page it's fairly obvious how I deduce the remainder of these attributes which form the central core of the theistic notion of God: a personal Creator, uncaused, beginningless, changeless, immaterial, timeless, spaceless, enormously powerful, and intelligent. In the words of Thomas Aquinas, this is what everybody means by God.

Notes

{1} "Modernizing the Case for God," Time (April 7, 1980), pp. 65–66.

{2}Alvin Plantinga, "Two Dozen (or so) Theistic Arguments," 33rd Annual Philosophy Conference, Wheaton College, October 23–24, 1986.

{3}David Hume to John Stewart, February, 1754, in The Letters of David Hume, ed. J. Y. T. Greig (Oxford: Clarendon Press, 1932), 1: 187.

{4}Immanuel Kant, Critique of Pure Reason, A 189 / B 232; A 196 / B 241.

{5}David Hilbert, "On the Infinite," in Philosophy of Mathematics, ed. Paul Benacerraf and Hilary Putnam (Englewood Cliffs, N.J.: Prentice–Hall, 1964), p. 151.

{6}David Hume, Enquiry concerning Human Understanding, 12.II. 125.

{7}Kant, Critique, A 426 / B 454.

{8}P. C. W. Davies, "Space–time Singularities in Cosmology," in The Study of Time III, ed. J. T. Fraser (Berlin: Springer Verlag, 1978), pp. 78–79.


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