Questions on Cosmology (part 1)
Questions on Cosmology (part 2)
Questions on Cosmology Pt. 1
Kevin Harris: Kevin Harris in the studio with Dr. William Lane Craig. Boy, do we get some doozy questions. I'm not sure what a doozy is, but we get them. This question comes from someone who's read the new book from Mario Bunge, Matter and Mind: A Philosophical Inquiry. Dr. Craig?
Dr. Craig: Oh, yes, he's a very well-known naturalistic philosopher and a philosopher of science.
Kevin Harris: What he argues for is the existence of physical, spatial, and temporal infinities, and the fact that naturalism, if true, implies that the universe is eternal. He writes,
One such universal feature is that all physical quantities, with the possible exception of some properties of the universe as a whole, are finite. Consequently, any theory including infinities (singularities, “divergences”) must be false.
The ban on physical infinities may have two exceptions: the size and age of the universe. Indeed, at the time of writing we do not yet know whether the universe is spatially finite or infinite, and there is no compelling argument for a beginning of time. Philosophy cannot help with the question of spatial infinity, but it is not indifferent to the question of temporal origin: any naturalistic ontology will demand that the universe has always existed.
Well, we can stop right there and say that, yeah, there are plenty of good arguments for the beginning of time.
Dr. Craig: Well, I think that this is a very interesting statement by Bunge. He says that any naturalistic ontology entails that the universe is eternal in the past. Therefore, if the evidence suggests that the universe is not eternal in the past that means that the evidence is against naturalism. So he has really put his naturalism on the line here. He is unwilling to accommodate the finitude of the past. He says naturalism entails an eternal universe. And that leads right into an argument: the universe is not eternal, therefore naturalism is not true. So this is a very interesting and bold position that he's advocating.
Kevin Harris: Regarding the Big Bang Bunge writes,
What about the Big Bang, which is usually supposed to have occurred between 10 and 20 billion years ago? At present there are at least three possible answers to this question.
1. The Big Bang happened, and it was God's creation out of nothing. This answer is obviously unacceptable to any physical cosmology, for it invokes the supernatural and violates Lucretius's ex nihilo nihil principle.
Dr. Craig: Alright. Notice his response to the theological option. It's good that he at least recognizes this as an option, that God has created the universe, and that the universe did have a beginning. That would be the option I prefer, in fact. What is his refutation of it? It's inconsistent with naturalism. [laughter] He says, if you're a physicalist then you can't believe in this. Right, right. But that's no reason not to think the view is true. So that is really, I think, just a question-begging rejection of the theological alternative.
Now, he does add that this is inconsistent with Lucretius' principle that “out of nothing, nothing comes.” And I think that's clearly mistaken because on the theistic view the universe doesn't come into being out of nothing in the sense that it has no cause. Rather it comes into being because it has an efficient cause. God created the universe and therefore it is not a violation of Lucretius' principle that “out of nothing, nothing comes.” We agree with that as theists, that things don't just pop into being uncaused out of nothing. What the theist maintains in the case of the universe is that although the universe lacked a material cause it did have an efficient cause, that is to say, it has a productive cause which brought the matter and energy into being. And therefore it is in no sense a violation of Lucretius' principle. So his arguments against the theological answer to this question are in the first place question-begging, and in the second place misconceived.
Kevin Harris: Yeah, it's just like Dawkins' “We can't allow a divine foot in the door.”
Dr. Craig: Right.
Kevin Harris: He says the second possibility when it comes to the Big Bang is,
The Big Bang is only a simplistic interpretation of the singularity occurring in the simplest of all cosmological models. This model assumes that the universe is the maximal balloon, and that there is a cosmic time in addition to the uncounted local times attached to all the possible reference frames . . . even admitting this model does not force us to interpret the time at which the radius of the universe was nil as the origin of the universe.
You'll have to unpack that for us a little bit.
Dr. Craig: Alright. This is, again, I think, a rather desperate attempt to refute the idea that time and the universe had a beginning, at least in the standard model. He says how do we know in addition to all the local reference frames that the Special Theory of Relativity imagines there is a kind of universal cosmic time that measures the duration of the universe? Well, that emerges in the context of the General Theory of Relativity. When it is applied to the universe as a whole there does emerge a cosmic time which measures the proper time of the duration of the universe. And when cosmologists say that the universe originated 13.7 billion years ago they are referring to this cosmic time, which is the same for every local observer in the universe, and measures the duration of the universe as a whole. And it's true that this was a feature of the simplest models, developed originally by Friedman and L'ametre, in which they assumed that the universe is homogeneous and what's called isotropic, the same in every direction, and is expanding in this way. And the discovery since those theories were first proposed in the 1920s have revealed that the universe on large scales is far more homogeneous and isotropic than early theorists ever could have imagined. The microwave background radiation that permeates the universe is isotropic down to one part out of a hundred thousand—it is amazingly uniform. So the idea that there is this cosmic time that measures the duration of the universe is very well established, and therefore gives us quite good grounds for thinking that the universe is about 13 billion years old.
As for Levy-Leblond's article, which was published twenty years ago in 1990, I actually responded to that at the time. All Levy-Leblond does is try to push back the origin of the universe to past infinity by fiddling with the metric of time so that it is, as it were, to put it in layman's terms, he takes the Big Bang singularity and he just stretches it out so that the beginning of the universe occurs infinitely long ago. But what Levy-Leblond doesn't do is get rid of the beginning of the universe. He just has it be infinity distant in the past, but on his view the universe still began to exist. So he doesn't avoid the beginning of the universe, in fact, at all. So that second alternative that Bunge suggests in unsuccessful.
Now, having said that, I would readily agree that the standard model is over-simplified, and that it will be modified, and in all probability is going to be affected by the development of some sort of quantum theory of gravity. But that gives no reason to think that the absolute beginning of the universe that's predicted by the standard model is going to be removed by these new quantum gravity models. The origin of the universe may be non-singular, as it is in the Hartle-Hawking no-boundary proposal. So the presence of the singularity, which is a feature of the standard model, is not a necessary condition of the universe's having begun to exist.
Kevin Harris: And when you say that the universe is very isotropic, it's expanding at a very even way, rather than real haphazard or jaggedly?
Dr. Craig: Exactly. There is a, how should I say, a division of spacetime. You can slice up four-dimensional spacetime in such a way that this expansion proceeds smoothly and uniformly and yields this cosmic time which measures the duration of the universe. And that emerges in the context of the General Theory of Relativity and the application of relativity to the cosmos as a whole.
Kevin Harris: The third possible answer to the Big Bang, according to Bunge, is that,
The Big Bang did happen, but it was only the sudden and worldwide expansion of the universe that existed earlier in a state about which we know nothing. Nor will we ever discover anything about the pre-Big Bang universe, because the explosion destroyed the records. One possibility is that the event consisted in the sudden emergence of ordinary mater (electrons, photons, etc.) out of the pre-existing electrodynamic vacuum, or space filled with “virtual” particles. But, given the scarcity of astronomical data, and the unrestrained fantasy of cosmologists, I suggest suspending judgment until more realistic cosmological models are crafted.
In any event, we should heed Tollman's warning at the end of his massive treatise: “we must be specially careful to keep our judgments uninfected by the demands of theology and unswerved by human hopes and fears. The discovery of models, which start expansion from a singular state of zero volume, must not be confused with a proof that the actual universe was created at a finite time in the past.”
Now, that was written in, like, 1934.
Dr. Craig: Yeah, here I think, again, you see the defensiveness. You can tell that these folks are on the defensive – “We mustn't yield to theology;” “We mustn’t allow that to encroach here.” Clearly, I think, naturalists are feeling the pressure, and you'll remember the only reason he had for rejecting the theological alternative was because it's non-naturalistic. No naturalist could accept it. In effect in this third alternative he really abandons any confidence that naturalism is true. It just is agnosticism. He just wants to say, “We don't know.” And that is to abandon any confidence, then, that the naturalistic view is true. It could well be that the universe did begin to exist. In fact I would suggest that Bunge's information here is somewhat dated, because what he's thinking about here is models of the universe in which our expanding universe originates out of the quantum vacuum as some sort of a fluctuation of the energy locked up in empty space. But the problem is that inflation theorists, like Alan Guth and others, have recognized that this quantum vacuum cannot be eternal in the past. It itself must have begun to exist. Inflationary cosmology cannot be past eternal. Inflationary cosmology can be future eternal, it can go on forever. But it can't be past eternal. So even if you say that our observable universe originated out of such a quantum state that quantum state itself cannot be eternal in the past, but must have had a beginning. And therefore, in fact, he hasn't succeeded in answering the question that is put to the naturalist—doesn't the evidence of contemporary physics and cosmology give grounds for believing that the universe is not temporally infinite in the past?
Kevin Harris: Do you think he has sufficiently highlighted the three major explanations of the Big Bang?
Dr. Craig: Well, it would seem to me that those would be basically the alternatives, although what theory you enunciate under number three is going to vary wildly. I suppose another possible alternative, though I think ultimately it's incoherent, would be that the universe created itself. That's what Daniel Dennett thinks—that the universe via “the ultimate bootstrapping trick” brought itself into existence. Or I suppose another possibility, as long as we're just talking possibilities, would be to say the universe popped into being uncaused out of nothing—but that would violate Lucretius' principle ex nihilo nihil fit. So Bunge wouldn't be open to that. So I think he's listing here what he would see . . . well, I was going to say what he would see as the three credible possibilities, but he doesn't think the first one is credible.
Kevin Harris: Because it violates his naturalism.
Dr. Craig: Right, because it's non-naturalistic. But at least, to his credit, he includes it in the list. And I think the weakness of his reason for rejecting it is quite apparent.
Kevin Harris: I hear all the time that the fear of those in the scientific enterprise is that if you allow a divine foot in the door, if you allow for God and theology, something that Bunge is complaining about here, that it opens the door to irrational explanations. When the mushroom puts out certain spores it will in the morning create a circle of mushrooms called fairy rings. And the fear seems to be, Bill, that if you start allowing any kind of a supernatural explanation, well then in science class you could say, “Hey, one possibility is that fairies did indeed cause these rings of mushrooms,” rather than the fact that we've observed that the spores shoot out that way, in a circular way, and that's what causes it. So, well, in one sense it's comparing God and fairies—which is a problem. But do you see the anxiety of why they don't want to do that?
Dr. Craig: Oh, sure. I understand it. They're saying that science needs to adopt a sort of methodological naturalism in order to prevent these boogems and other spooks from getting into science. And I think it's really important to understand, Kevin, that I'm not advocating some kind of theistic science. I'm not advocating creation science here of any sort. I'm not saying that we should introduce supernatural explanations into science. I'm offering a philosophical argument for the existence of God, and it's quite consistent with having methodological naturalism within science. What I would just say, then, is what Robert Jastrow said in his book God and The Astronomers,that science conducts us to the threshold of eternity, to the beginning of the universe, and then science is impotent to answer the question as to why the universe came into being. That's a non-scientific question—that's a metaphysical question, not a physical question.
Kevin Harris: Then philosophy takes over at that point.
Dr. Craig: Right, it's metaphysics; not physics. So I'm quite happy to say, fine, adopt methodological naturalism in science. I'm not proposing any kind of theistic science. I'm not proposing an alternative to the Big Bang theory, some kind of theistic Big Bang. Not at all. I'm just suggesting that the evidence of contemporary cosmology supports the truth of the second premise of the kalam argument—that the universe began to exist. That's a religiously neutral statement which can be found in any textbook on astronomy and astrophysics, and has nothing to do with God or theism. So I'm not suggesting that we adopt theistic science or creation science. I'm not suggesting that we postulate God as an entity in a scientific theory at all. I'm doing metaphysics, not physics. So I think that that concern is simply not germane to my argument. Now, beyond that I think we could well call into question why methodological naturalism does need to be adopted. Why not allow supernatural explanations into the pool of live explanatory options? They would be assessed by the same criteria that other explanations are assessed—such as plausibility, explanatory power, explanatory scope, and so forth. And I'd be quite willing to allow that if you have a naturalistic theory and a supernaturalistic theory, and they have the same explanatory power, the same explanatory scope, the same plausibility, that we ought to prefer the naturalistic theory rather than opt for the supernaturalistic one. It would only be in the case that the supernaturalistic hypothesis exceeds the naturalistic hypotheses in either explanatory scope, explanatory power, degree of ad hoc-ness, or being free from being ad hoc, that then one would adopt the supernatural explanation over the naturalistic one.
Kevin Harris: So would everyone be a lot happier on both sides of the raging controversy if we just adopted a methodological naturalism?
Dr. Craig: Well, I don't know if people on both sides would be happy, but certainly the naturalists would be happier about that—I hope they would, anyway, because one would be meeting them halfway. One would say, “I don't agree with methological naturalism but I am not in any way trying to introduce a theistic science. I am just saying that the best scientific evidence we have supports the premise that the universe began to exist.”
Kevin Harris: This is very important, what you're saying, because it's just such a bone of contention.
Dr. Craig: Yes, this completely gets rid of the silly god of the gaps objections because you're not postulating God to fill up some explanatory gap in science.
Kevin Harris: So if educators in American said, “We should adopt methodological naturalism as a tool,” you wouldn't have any problem with that.
Dr. Craig: Well, I wouldn't say I wouldn't have any problem with it, Kevin. As I said, I think that you can defend the notion of having supernaturalistic explanations as part of the pool of live explanatory options. I don't see any good reason to adopt methodological naturalism. But I'm just saying, if you do, it has no impact upon the argument I'm offering.
Kevin Harris: What would you call your methodology then? Would you call it “Wherever the evidence points” methodology? [laughter]
Dr. Craig: Well, no, I'm just doing metaphysics is all.
Kevin Harris: Okay.
Dr. Craig: I'm not proposing theistic science. I'm just doing metaphysics; I'm offering a philosophical argument for God's existence, the second premise of which has considerable empirical evidence in its favor. As I said, in a science class one wouldn’t say anything about God if one is using methodological naturalism. You would just come to the end of science and say that this is where science conducts us but no farther. Now, where the naturalistic scientist can push the envelope further is what Bunge tries to do in option three. He can say, wait a minute, wait a minute, here are some naturalistic theories that will push the threshold of science further back. We can postulate this quantum mechanical vacuum state out of which our universe emerged, and that will provide a purely naturalistic explanation of the origin of the universe. And at that point someone who's taking the line that I'm taking will need to deal with that as a defeater, a potential defeater, of the second premise that the universe began to exist. And he will examine what science tells us about this vacuum state, and what he'll discover is that it's unstable, that it cannot procure for infinite time, and that therefore even this state must have a beginning, and he'll suddenly discover that the evidence supports, in fact, that second premise, again, that the universe began to exist.
 Mario Bunge, Matter and Mind: A Philosophical Inquiry (New York: Springer, 2010), p. 26.
 Ibid., pp. 26-27.
 Ibid., p. 27.
 “It [the material world], we have seen, does perform a version of the ultimate bootstrapping trick; it creates itself ex nihilo, or at any rate out of something that is well-nigh indistinguishable from nothing at all.” from Daniel Dennett, Darwin’s Dangerous Idea (New York, NY: Simon & Schuster, 1995), p. 185.
 Total Running Time: 20:01 (Copyright © 2011 William Lane Craig)
Questions on Cosmology Pt. 2
Kevin Harris: Welcome to the podcast—the Reasonable Faith podcast. It's Kevin Harris in studio with Dr. William Lane Craig. We have been sorting through these questions, Bill. Here's a question from someone who's studying at Flinders University of South Australia, and he's developing an argument for God. Here's what he says:
I've been considering writing an argument for God, and I'm a great admirer of your work, and I'm seeking advice from you as to whether this is a good argument—if you'll take a look at it. And here it is, and it's pretty easy to lay out.
1. The number 1 exists. [That's pretty funny—number one, the number one exists.]
2. The number 1 is not contingent on the existence of the universe in order to exist.
3. Therefore, the number 1 exists apart from space and time.
4. The number 1 can only be perceived by a mind.
5. The universe requires the number 1 to exist.
Therefore, through (3), (4), and (5), the best explanation for the existence of the number 1 is a mind that is separate from space and time.
As a Christian, I'm worried about any theological complications that might emerge from me refining and making such an argument. I'd also like to seek advice on the best way for me to develop this argument in my doctoral studies.
Dr. Craig: Well, what he has here is a sort of conceptualist argument for God's existence. Such an argument has been floated by Alvin Plantinga and defended in detail by Quentin Smith. If he'd be interested in my book Philosophy of Religion: A Reader and Guide, which is published by Edinburgh University Press in the U.K. and Rutgers University Press in the United States, Quentin developed this conceptualist argument for God's existence. And I think it's a very, very interesting argument that would form the grist for a good paper or a thesis, as he wants to write. Now, I think his own statement of the argument needs to be tightened up a little bit. For example, his first premise is that the number 1 exists, and then later on he says that the universe requires the number 1 to exist. Now, I don't think that those are two independent premises, rather the second one would seem to be the evidence he would give for premise (1). Why do we think the number 1 exists? Well, because the universe requires the number 1 to exist. And here he would need to flesh this out. In what way does the existence of the universe require the number 1 to exist? Perhaps he would say something like this: 1 is the number of universes that there are – or something of that sort – and therefore the number 1 exists. And then he says the number 1 is not contingent on the existence of the universe in order to exist, and that would seem to be right, that although the universe would provide some sort of evidence for the existence of the number 1, the number 1 would not be something that would be contingent on the universe. And so the number 1 would exist independently of space and time. But then he says the number 1 can only be perceived by a mind. Now I think what he really means there is that the number 1 can only exist in a mind, as a concept of a mind or as an idea of a mind. In other words, this is the conceptualist move. He wants to say that mathematical objects like the number 1 are not independently existing objects but are somehow the contents of consciousness. Not simply that they're perceived by mind but they are in some way ontologically constituted by mental activity, or something, and therefore the best explanation for the existence of the number 1 would be some sort of a mind, which is separate from time and space, and independent of the contingent universe, which would go a long way toward theism. Quentin goes on to argue that because this mind must ground all mathematical truths, which are infinite in number and necessary in their existence, it follows that this is a metaphysically necessary omniscient mind, which really goes a long way toward theism.
So I would say that this has definite promise for an argument for the existence of God. My reservation is that I'm not sure the number 1 does exist! I am increasingly inclined toward a nominalistic view of abstract objects, like numbers, to say that these things really don't exist at all. Now, certainly, we can have an idea of the number 1 but that doesn't mean that your idea is the number 1. I can have an idea of a unicorn but a unicorn is not an idea. A unicorn, if it exists, is something like a horse, a warm-blooded mammal with a horn in its head—it's not an idea. And similarly with a number: I'm not sure that a number just is an idea, although I can have an idea of a number. But this is a defensible and interesting position, which I think I would encourage our friend to keep working on.
Kevin Harris: Could he use any number—could he use the number 7?
Dr. Craig: Oh, sure, sure. Any number here is arbitrary.
Kevin Harris: If I'm hearing you right it sounds like number (5) of his premises is the most controversial one: the universe requires the number 1 to exist.
Dr. Craig: Yes, that would be a key move, and he doesn't tell us why he thinks that's true. That would be a really key move, is why should we think that these things exist at all?
Kevin Harris: Sure. It seems in one sense if there weren't a universe that there would be nothing to count. There would be nothing to which the number 1 applied.
Dr. Craig: Well, except he's arguing that if numbers exist they would exist necessarily, they would not be contingent on the universe, and I think that's right. It's very hard to see how numbers could be things that would be contingent in their being. It would seem that if they exist they exist necessarily. So you kind of have an ontological argument for the reality of numbers, incipient here, that numbers are either impossible or they're necessary in their existence. I'm rather inclined to accept that.
Kevin Harris: Would numbers, then, if they don't exist in that way, kind of where you're leaning, Bill, would they exist only epistemically but not ontologically?
Dr. Craig: I think that would be one way to put it, yes. I think I understand what you're saying. We can conceive of this just as we can conceive of other non-existent things.
Kevin Harris: And this overlaps into questions we get about the so-called transcendental argument from time to time, and that is the laws of logic, similar to numbers, could not exist if there were not a mind.
Dr. Craig: Right, that would be a similar sort of move, trying to ground logic in an omniscient mind, a necessary mind.
Kevin Harris: Alright. Got a question here on Alvin Plantinga's work. And he says,
Dr. Craig, you argue that the cause is likely a personal agent [we talked about the kalam]. You claim that since abstract objects, like numbers, do not have causal properties – they can't cause anything – that therefore the cause is likely an intelligent mind. How would you respond to someone who uses the escape route of trying to show that unembodied minds are impossible, and therefore the cause cannot be an immaterial intelligence?
Dr. Craig: This is an argument for the personhood of the cause of the universe, that you arrive at through the cosmological argument. And I hit upon this through my work on the existence of abstract objects like numbers such as was discussed in the last question. If mathematical objects and other abstract objects exist, what characterizes them, what is definitive for them, is that they're causally impotent. Concrete objects have effects. They have causal powers, whereas abstract objects like mathematical entities are devoid of causal powers. So it occurred to me if there must exist, as the cosmological argument implies, an uncaused, immaterial, timeless, spaceless entity which is the explanation of the origin of the universe or the existence of the universe, what could it be? Well, as I think down through the history of metaphysics the only candidates that I come up with that could fit that description would be either an abstract object or an unembodied mind or consciousness. Both of these could be characterized by the properties of being uncaused, immaterial, timeless, and spaceless. But an abstract object could not be the cause of the universe because it's essential to abstract objects that they're causally impotent, and therefore that would imply that the cause of the universe must be an unembodied mind or consciousness. Now the questioner says, well, what if someone says that such a thing is impossible? Well, then I invite them to give their argument. I have just given an argument for the reality of an unembodied mind. I haven't just asserted it. I've given an argument for it. So if they want to maintain this is impossible, they need to give some sort of an argument that there can be no such thing as an unembodied mind. And I don't know of any good argument for that. Most of the arguments for physicalism or reductive materialism or some other view of mind would typically try to show correlations between the human brain and mental states, and therefore maintain that human consciousness is in some way essentially dependent upon physical brain states, and so forth. But none of that does anything to show that the notion of an unembodied consciousness is metaphysically impossible. Indeed, we've just seen a good argument for it. So I'd just wait for the objector to give his argument—he is the one who bears the burden of proof here if he's going to maintain that this explanation we're offering is impossible. We need to hear from him his proof or argument that such a thing is impossible.
Kevin Harris: Yeah. I mean, even the questioner says if they want to take an escape route by trying to show that unembodied minds are impossible—okay, well, then show it.
Dr. Craig: Right.
Kevin Harris: Show that you can do it.
Dr. Craig: Yeah, I think far too often Christians assume the burden of proof unnecessarily when it's up to the skeptic to provide warrant for his defeaters that he gives. When you give an argument and a defeater is brought against it that defeater has to have more warrant than your own premise if it's to be a successful defeater. It's not enough just to suggest possible defeaters. It's not enough to just lay out possibilities. You have to support your defeater by giving some kind of evidence and arguments, some sort of warrant. If there's less warrant for the defeater than for the premise then the defeater is unsuccessful—it's a non-starter.
Kevin Harris: Have you seen anybody try to come up with a third option, as far as our alternatives that fit the bill – that would be abstract objects or an unembodied mind – has anybody offered a possible third? Because that's the only two that I can think of.
Dr. Craig: Not that I've seen named. Recently I responded to a question of the week where the person was saying, well maybe there could be an impersonal unembodied cause. But the problem was he wasn't able to name it – it was just words – and there's no candidate there. So I don't know.
Kevin Harris: Sounds like an abstract object.
Dr. Craig: Yeah, I mean, an abstract object, that would be a candidate, a mind would be an object. But then if there is another alternative I'm happy to add it to the list and consider it. But I can't add it unless you name it. To just say, “Well, maybe there's some unknown something, some unknown x” isn't to offer an alternative hypothesis.
Kevin Harris: Another question that came to ReasonableFaith.org.
Dr. Craig, as a theist I've been defending the existence of God in cyberspace, but there are a few questions to which I want some simple and brief answers to polish my arguments. First, [we'll take these one at a time] if God created out of nothing would this not violate the principle that out of nothing can only come nothing?
Dr. Craig: It's very important to distinguish in this connection between different types of causes. Aristotle distinguished between efficient causes and material causes. The efficient cause is that which produces its effect in being. A material cause is the stuff out of which a thing is made. So, for example, take Michelangelo's statue The David. The efficient cause of The David is Michelangelo himself, the sculptor. The material cause of The David is the block of marble which Michelangelo sculpted into the shape of The David. So when we say that God created all the matter and energy in the universe, and he created the universe out of nothing, we are not saying that out of nothing nothing came. Rather we're saying that the universe has an efficient cause but it has no material cause. So this is not a violation of the principle out of nothing nothing comes, which is to say being cannot come from non-being. On the contrary, we affirm that. There has to be some sort of cause for anything that begins to exist. And in this case we have an efficient cause of the origin of the universe, but not a material cause of the origin of the universe.
Kevin Harris: Yeah. It's easier to imagine that if there was stuff floating around that God could have used to craft something, that makes more sense to we as human beings. But that's not an option.
Dr. Craig: Not if the arguments against an infinite temporal regress are sound; no, you have to get back to an absolute origin of all matter and energy, and even space and time themselves, at least in contemporary cosmology. So we have good reason to believe that the universe doesn't have a material cause, that the matter and energy of the universe were themselves created. On the atheist position it seems to me you're landed in a double absurdity because you have to say the universe had neither a material nor an efficient cause. And that, I think, is surely absurd. That contradicts the principle that out of nothing nothing comes.
Kevin Harris: Question number two: “How could the argument that God is the cause of all things avoid the fallacy of begging the question?”
Dr. Craig: Well, I don't understand why he thinks that the argument would be circular. To beg the question means that your only reason for affirming a premise is that you already believe the conclusion. But in the case of the kalam argument the two premises are: “whatever begins to exist has a cause,” and the second premise is “the universe began to exist.” And in the reasons that I give for affirming those premises neither of them assumes the conclusion, “that God exists,” so they're not question-begging. With respect to the causal premise, for example, which is the one he's asking about, I think, the reasons I give are first of all, that it's a metaphysical first principle that something cannot come into being from nothing – out of nothing nothing comes. The second one is that if things can come into being uncaused out of nothing then it becomes inexplicable why just anything and everything doesn’t come into being out of nothing. And then the third evidence is inductive evidence of science and everyday experience that things don't just pop into being uncaused out of nothing. We see things that come into being do have causes. So none of those is a circular or question-begging argument in favor of the causal premise, which I think we have ample reason to accept—certainly more so than its contradictory.
Kevin Harris: Third and final question that he asks: “Should we assume that everything exists unless proven otherwise? Who bears the burden of proof? Does it lay with the atheist or the theist?”
Dr. Craig: Well, certainly . . . well, I was going to say certainly we should not assume that everything exists. But actually, this is a very subtle point, Kevin. The great Harvard philosopher W. V. O. Quine, when asked “What exists?” his answer was, “Everything.” Everything exists because things that don't exist aren't things. So it's not as though there are things that don't exist in Quine's view. So Quine would actually say, yeah, everything exists and that's it.
Kevin Harris: It's almost a tautology—isn't it?
Dr. Craig: Now, the problem is that's very misleading. If you say, “Everything exists” the layperson will think, “Oh, well, then centaurs exist, unicorns exist.”
Kevin Harris: Mermaids!
Dr. Craig: “Mermaids exist, married bachelors exist.” No, what the Quinian would say is that those aren't really things. And so he's not saying that all possibilities are actualized. And I think that's what this fellow is asking in the question, and in that sense, no, we shouldn't assume that everything exists. There are obviously true propositions that are negative existentials – like mermaids do not exist, centaurs do not exist – those are true statements, and they don't imply that there are mermaids or centaurs. So, no, we shouldn't assume in that sense that everything exists. And so if someone asserts that God exists and means to offer this in a context of an argument, he needs to give some warrant for that. On the other hand if an atheist asserts that God does not exist, and he's doing this in the context of an argument or a debate, he needs to offer some warrant for that negative existential proposition. Both of these make assertions to know something, and if you're doing this in an argumentative context then you need to offer some sort of warrant for thinking that's true. Otherwise you're just believing by faith.
Kevin Harris: And it seems that he's asking in a sense, as well, okay, should I assume that leprechauns exist until I'm proven wrong? That is thrown at you in cyber-debates all the time. The second thing that is thrown at you is anyone who claims the existence of something bears the burden of proof.
Dr. Craig: And that's very different from that first statement. I wouldn't agree that you think that leprechauns exists until proven otherwise. But nevertheless someone who makes a negative existential assertion is making a claim, and if he wants me to believe it he needs to give some sort of warrant for it. There isn't a differential burden of proof here between those who make positive existential assertions and those who make negative existential assertions. The middle ground, which makes no assertion, is simply to say, I don't know whether x exists or x does not exist. That's the agnostic position—and that's the truly middle ground because it asserts nothing.
Kevin Harris: So would it be if there were such a thing it would kind of be the default position?
Dr. Craig: Right, that would be the neutral, default position if you're in an argumentative context where you're trying to commend your beliefs to someone else and persuade them that they should join you in believing this.
Kevin Harris: Okay. We'll look at some more questions next time on the podcast. Thanks for joining us on Reasonable Faith with Dr. William Lane Craig.
 Total Running Time: 20:36 (Copyright © 2011 William Lane Craig)