Q & A - On the Nature of Time
October 12, 2009 Time: 00:15:46
Summary
Conversation with William Lane Craig.
Transcript Q & A - On the Nature of Time
[Before the discussion starts, details about Reasonable Faith chapters are discussed. The actual podcast discussion, and this transcript, picks up at the 4 minute 5 second mark.]
Kevin Harris: Dr. Craig, we have lots of questions that come to ReasonableFaith.org. Let’s look at a few of these. This says,
Dear Dr. Craig, in his debate with a Christian, an atheist mentioned you a number of times and said this during his first rebuttal: “You say that Quentin Smith says that if you are an atheist or a naturalist and you accept the Big Bang theory then you have to believe it came out of nothing. This is simply false. Because I corresponded privately with Quentin Smith as well as almost every other atheist philosopher in the United States, Canada, England, and Australia and I conducted a non-scientific poll. I am here to tell you that unanimously all of the philosophers that I asked said that an atheist does not have to believe that the universe popped into existence out of nothing to accept the Big Bang theory.” He goes on to quote Quentin Smith who said, “I agree with Graham Oppy that William Lane Craig is just relying on slogans, especially when he uses ‘out of nothing, nothing comes.’” Quentin Smith in that quotation was referring to Graham Oppy, an Australian philosopher, who had also written a quote: “I think this is an instance of Craig’s reliance upon slogans.”
We have two things to talk about here. [1] First of all, can the naturalist believe that the universe just “is” and that it didn’t simply pop into existence out of nothing? We need to address that. Then we need to address this accusation about slogans.
Dr. Craig: OK, good, Kevin. I think you have separated accurately the two issues that seemed to be raised in this question. I would respond to the first by saying that certainly the naturalist is able to say that a universe with a beginning simply “is” without coming into being out of nothing if he is willing to adopt a certain theory of time that permits that. I’ve said this explicitly in my work. Behind the so-called kalam cosmological argument lies a view of time which is variously called the tensed theory of time or a dynamic theory of time or, to borrow the convenient terminology of J. M. E. McTaggart, the A-theory of time. This is a theory of time that is the common sense view of time that is almost universally accepted among ordinary people. It is the view that temporal becoming is a real and objective feature of reality; that there is a difference between the past, present, and the future. The future doesn’t exist in any sense. It is a realm that is pure potentiality. The past did exist but no longer exists. The present alone is real. Things really do come into being and go out of being with the lapse of time. On that view, if the universe began to exist then the universe definitely did come into being at the first moment of its existence without any sort of antecedent conditions. It came into being from nothing. Not in the sense that there was a prior state of reality which is a state of nothingness; rather, it came into being out of nothingness in the sense it came into being at that first moment of its existence and there was nothing before it. That is to say, there was not anything before it. So in that sense the coming into being of the universe is a tensed fact that happens at the first moment of its existence, and it does so without any sort of causal antecedents.
It is only if you adopt a tenseless or static or so-called B-theory of time, according to which all events in time are equally real, that you could say the universe has a beginning but that the universe didn’t come into being at that first moment. All moments of time are equally real. The universe on that view has a beginning only in the sense that a yardstick has a beginning in the sense that it has a first inch. But the yardstick doesn’t come into being at the point of its first inch. It simply is extended in space. In a similar way, the B-theorist would say the universe is extended in time.
This is a point that I’ve made myself so this is not any sort of insight on the part of the critic of the argument. I’ve made it very clear in my presentation of the argument that the argument is based upon an A-theory of time – a tensed theory of time – and that is why I devoted two volumes in the Synthese Library published by Springer-Verlag on a defense of the A-theory of time and a critique of the B-theory of time. [2]
Kevin Harris: If the B-theory of time somehow turned out to be true – some kind of a new insight came in or something – that would do some damage to the kalam cosmological argument?
Dr. Craig: Right. I think then the premise that “whatever begins to exist has a cause” would no longer be evidently true because the universe didn’t come into being when it began to exist. It is really not beginning to exist that is the key thing here. It is coming into being. That is what happens if temporal becoming is a real and objective feature of reality. At the first moment of its existence, the universe comes into existence. I maintain that nothing can come into existence without a cause. Something can’t come into existence from nothing. Now, on the B-theory, as I say, time and the events in time are extended like a spatial length – like a yardstick. And a yardstick doesn’t come into being at the first inch of its extension. [3] Similarly, the universe on this view just exists as a static whole from the first moment of its existence to the last moment of its existence, if there is one. So on that view the universe doesn’t really come into being in virtue of its beginning to exist. So if the skeptic wants to deny the first premise of the argument – that whatever begins to exist has a cause – he needs to give us good grounds for thinking that the B-theory of time is true.
Kevin Harris: He’s got his work cut out for him.
Dr. Craig: I think so. He’s got to refute all of the evidence and arguments in favor of the A-theory and all of the objections that I lodge against the B-theory, and do the same sort of thorough work that I’ve done in defending his theory of time to show that the universe can begin to exist and yet not come into being at the first moment of its existence.
If he were to do that then I think what the theist would appeal to is not the kalam cosmological argument but what I call the Leibnizian cosmological argument – namely, Leibniz’s question, “Why is there something rather than nothing?” Why does this tenseless, spacetime manifold exist? That question still needs to be answered. So the Leibnizian version of the cosmological argument I think would still go through in spades.
Kevin Harris: I can’t help but chase this for just a moment because it is so fascinating. On the B-theory of time, time travel might be possible because there is actually a future – it is out there and exists, we just haven’t arrived. But if we could find a way to get to it then we could do it. The past is the same. The past still exists back there somehow, if we could find a way to go back to it and explore it. So if you are going to be a time traveler you need the B-theory, too, right?
Dr. Craig: That’s exactly right. And therefore it is no accident that all of the philosophers who defend the coherence of time travel are B-theorists.
Kevin Harris: You know, I think that because of pop culture, movies, and some of the great movies we’ve talked about – the time travel movies – I think that the layperson who is not trained in this area (the philosophy of time) just assumes that somehow, someway, time travel is true and therefore the B-theory is the valid theory.
Dr. Craig: I don’t know if they do, Kevin. I think you are certainly right that time travel movies are so engaging and entertaining. I enjoy them myself. I really like time travel movies even though I think that what they posit is, in the end, metaphysically impossible. On the other hand, though, I think people have a deep, deep sense that the future is open. That it is not yet in any way determined. It is not out there just sort of waiting for us to arrive at it. We will shape the future and it isn’t as real as the present. And things that are past have somehow literally past away. They are not as real as we are right now. That may vary, I suppose, from person to person, but even B-theorists admit that the view of the normal, average man so to speak will be an A-theoretic view of time.
Kevin Harris: What about this accusation leveled toward you on slogans – using slogans. Is this something that philosophers try to catch each other at from time to time?
Dr. Craig: I don’t think so typically. I find this an odd allegation. What they are referring to is my appeal to this sort of metaphysical first principle that out of nothing, nothing comes. Or something cannot come out of nothing. Or being cannot come from non-being. I think that, far from being mere slogans, these are articulations of a very fundamental principle of metaphysics that goes all the way back to Parmenides in ancient Greece. Parmenides argued that being can only come from being, and that being cannot come from non-being. It seems to me that is a very fundamental metaphysical insight that is more than just a slogan. It is really, I think, a self-evident principle when you think about it. So it would be I would say a primitive metaphysical principle beyond which it is very difficult to get. Everyone has sort of first principles or foundational principles. I think it is condescending to dismiss these as mere slogans because everyone ultimately has some sort of first principles in his metaphysics. For me, this is one of the most basic, and it has been recognized in the history of philosophy as one of the most basic principles. [4]